cregit-Linux how code gets into the kernel

Release 4.14 drivers/tty/n_gsm.c

Directory: drivers/tty
/*
 * n_gsm.c GSM 0710 tty multiplexor
 * Copyright (c) 2009/10 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *      * THIS IS A DEVELOPMENT SNAPSHOT IT IS NOT A FINAL RELEASE *
 *
 * TO DO:
 *      Mostly done:    ioctls for setting modes/timing
 *      Partly done:    hooks so you can pull off frames to non tty devs
 *      Restart DLCI 0 when it closes ?
 *      Improve the tx engine
 *      Resolve tx side locking by adding a queue_head and routing
 *              all control traffic via it
 *      General tidy/document
 *      Review the locking/move to refcounts more (mux now moved to an
 *              alloc/free model ready)
 *      Use newest tty open/close port helpers and install hooks
 *      What to do about power functions ?
 *      Termios setting and negotiation
 *      Do we need a 'which mux are you' ioctl to correlate mux and tty sets
 *
 */

#include <linux/types.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/fcntl.h>
#include <linux/sched/signal.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/ctype.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/bitops.h>
#include <linux/file.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/timer.h>
#include <linux/tty_flip.h>
#include <linux/tty_driver.h>
#include <linux/serial.h>
#include <linux/kfifo.h>
#include <linux/skbuff.h>
#include <net/arp.h>
#include <linux/ip.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/gsmmux.h>


static int debug;
module_param(debug, int, 0600);

/* Defaults: these are from the specification */


#define T1	10		
/* 100mS */

#define T2	34		
/* 333mS */

#define N2	3		
/* Retry 3 times */

/* Use long timers for testing at low speed with debug on */
#ifdef DEBUG_TIMING

#define T1	100

#define T2	200
#endif

/*
 * Semi-arbitrary buffer size limits. 0710 is normally run with 32-64 byte
 * limits so this is plenty
 */

#define MAX_MRU 1500

#define MAX_MTU 1500

#define	GSM_NET_TX_TIMEOUT (HZ*10)

/**
 *      struct gsm_mux_net      -       network interface
 *      @struct gsm_dlci* dlci
 *
 *      Created when net interface is initialized.
 **/

struct gsm_mux_net {
	
struct kref ref;
	
struct gsm_dlci *dlci;
};

/*
 *      Each block of data we have queued to go out is in the form of
 *      a gsm_msg which holds everything we need in a link layer independent
 *      format
 */


struct gsm_msg {
	
struct list_head list;
	
u8 addr;		/* DLCI address + flags */
	
u8 ctrl;		/* Control byte + flags */
	
unsigned int len;	/* Length of data block (can be zero) */
	
unsigned char *data;	/* Points into buffer but not at the start */
	
unsigned char buffer[0];
};

/*
 *      Each active data link has a gsm_dlci structure associated which ties
 *      the link layer to an optional tty (if the tty side is open). To avoid
 *      complexity right now these are only ever freed up when the mux is
 *      shut down.
 *
 *      At the moment we don't free DLCI objects until the mux is torn down
 *      this avoid object life time issues but might be worth review later.
 */


struct gsm_dlci {
	
struct gsm_mux *gsm;
	
int addr;
	
int state;

#define DLCI_CLOSED		0

#define DLCI_OPENING		1	/* Sending SABM not seen UA */

#define DLCI_OPEN		2	/* SABM/UA complete */

#define DLCI_CLOSING		3	/* Sending DISC not seen UA/DM */
	
struct mutex mutex;

	/* Link layer */
	
spinlock_t lock;	/* Protects the internal state */
	
struct timer_list t1;	/* Retransmit timer for SABM and UA */
	
int retries;
	/* Uplink tty if active */
	
struct tty_port port;	/* The tty bound to this DLCI if there is one */
	
struct kfifo *fifo;	/* Queue fifo for the DLCI */
	
struct kfifo _fifo;	/* For new fifo API porting only */
	
int adaption;		/* Adaption layer in use */
	
int prev_adaption;
	
u32 modem_rx;		/* Our incoming virtual modem lines */
	
u32 modem_tx;		/* Our outgoing modem lines */
	
int dead;		/* Refuse re-open */
	/* Flow control */
	
int throttled;		/* Private copy of throttle state */
	
int constipated;	/* Throttle status for outgoing */
	/* Packetised I/O */
	
struct sk_buff *skb;	/* Frame being sent */
	
struct sk_buff_head skb_list;	/* Queued frames */
	/* Data handling callback */
	
void (*data)(struct gsm_dlci *dlci, u8 *data, int len);
	
void (*prev_data)(struct gsm_dlci *dlci, u8 *data, int len);
	
struct net_device *net; /* network interface, if created */
};

/* DLCI 0, 62/63 are special or reserved see gsmtty_open */


#define NUM_DLCI		64

/*
 *      DLCI 0 is used to pass control blocks out of band of the data
 *      flow (and with a higher link priority). One command can be outstanding
 *      at a time and we use this structure to manage them. They are created
 *      and destroyed by the user context, and updated by the receive paths
 *      and timers
 */


struct gsm_control {
	
u8 cmd;		/* Command we are issuing */
	
u8 *data;	/* Data for the command in case we retransmit */
	
int len;	/* Length of block for retransmission */
	
int done;	/* Done flag */
	
int error;	/* Error if any */
};

/*
 *      Each GSM mux we have is represented by this structure. If we are
 *      operating as an ldisc then we use this structure as our ldisc
 *      state. We need to sort out lifetimes and locking with respect
 *      to the gsm mux array. For now we don't free DLCI objects that
 *      have been instantiated until the mux itself is terminated.
 *
 *      To consider further: tty open versus mux shutdown.
 */


struct gsm_mux {
	
struct tty_struct *tty;		/* The tty our ldisc is bound to */
	
spinlock_t lock;
	
struct mutex mutex;
	
unsigned int num;
	
struct kref ref;

	/* Events on the GSM channel */
	
wait_queue_head_t event;

	/* Bits for GSM mode decoding */

	/* Framing Layer */
	
unsigned char *buf;
	
int state;

#define GSM_SEARCH		0

#define GSM_START		1

#define GSM_ADDRESS		2

#define GSM_CONTROL		3

#define GSM_LEN			4

#define GSM_DATA		5

#define GSM_FCS			6

#define GSM_OVERRUN		7

#define GSM_LEN0		8

#define GSM_LEN1		9

#define GSM_SSOF		10
	
unsigned int len;
	
unsigned int address;
	
unsigned int count;
	
int escape;
	
int encoding;
	
u8 control;
	
u8 fcs;
	
u8 received_fcs;
	
u8 *txframe;			/* TX framing buffer */

	/* Methods for the receiver side */
	
void (*receive)(struct gsm_mux *gsm, u8 ch);
	
void (*error)(struct gsm_mux *gsm, u8 ch, u8 flag);
	/* And transmit side */
	
int (*output)(struct gsm_mux *mux, u8 *data, int len);

	/* Link Layer */
	
unsigned int mru;
	
unsigned int mtu;
	
int initiator;			/* Did we initiate connection */
	
int dead;			/* Has the mux been shut down */
	
struct gsm_dlci *dlci[NUM_DLCI];
	
int constipated;		/* Asked by remote to shut up */

	
spinlock_t tx_lock;
	
unsigned int tx_bytes;		/* TX data outstanding */

#define TX_THRESH_HI		8192

#define TX_THRESH_LO		2048
	
struct list_head tx_list;	/* Pending data packets */

	/* Control messages */
	
struct timer_list t2_timer;	/* Retransmit timer for commands */
	
int cretries;			/* Command retry counter */
	
struct gsm_control *pending_cmd;/* Our current pending command */
	
spinlock_t control_lock;	/* Protects the pending command */

	/* Configuration */
	
int adaption;		/* 1 or 2 supported */
	
u8 ftype;		/* UI or UIH */
	

int t1, t2;		/* Timers in 1/100th of a sec */
	
int n2;			/* Retry count */

	/* Statistics (not currently exposed) */
	
unsigned long bad_fcs;
	
unsigned long malformed;
	
unsigned long io_error;
	
unsigned long bad_size;
	
unsigned long unsupported;
};


/*
 *      Mux objects - needed so that we can translate a tty index into the
 *      relevant mux and DLCI.
 */


#define MAX_MUX		4			
/* 256 minors */

static struct gsm_mux *gsm_mux[MAX_MUX];	
/* GSM muxes */

static spinlock_t gsm_mux_lock;


static struct tty_driver *gsm_tty_driver;

/*
 *      This section of the driver logic implements the GSM encodings
 *      both the basic and the 'advanced'. Reliable transport is not
 *      supported.
 */


#define CR			0x02

#define EA			0x01

#define	PF			0x10

/* I is special: the rest are ..*/

#define RR			0x01

#define UI			0x03

#define RNR			0x05

#define REJ			0x09

#define DM			0x0F

#define SABM			0x2F

#define DISC			0x43

#define UA			0x63

#define	UIH			0xEF

/* Channel commands */

#define CMD_NSC			0x09

#define CMD_TEST		0x11

#define CMD_PSC			0x21

#define CMD_RLS			0x29

#define CMD_FCOFF		0x31

#define CMD_PN			0x41

#define CMD_RPN			0x49

#define CMD_FCON		0x51

#define CMD_CLD			0x61

#define CMD_SNC			0x69

#define CMD_MSC			0x71

/* Virtual modem bits */

#define MDM_FC			0x01

#define MDM_RTC			0x02

#define MDM_RTR			0x04

#define MDM_IC			0x20

#define MDM_DV			0x40


#define GSM0_SOF		0xF9

#define GSM1_SOF		0x7E

#define GSM1_ESCAPE		0x7D

#define GSM1_ESCAPE_BITS	0x20

#define XON			0x11

#define XOFF			0x13


static const struct tty_port_operations gsm_port_ops;

/*
 *      CRC table for GSM 0710
 */


static const u8 gsm_fcs8[256] = {
	0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75,
	0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B,
	0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69,
	0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67,
	0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D,
	0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43,
	0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51,
	0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F,
	0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05,
	0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B,
	0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19,
	0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17,
	0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D,
	0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33,
	0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21,
	0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F,
	0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95,
	0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B,
	0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89,
	0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87,
	0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD,
	0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3,
	0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1,
	0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF,
	0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5,
	0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB,
	0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9,
	0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7,
	0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD,
	0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3,
	0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1,
	0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF
};


#define INIT_FCS	0xFF

#define GOOD_FCS	0xCF

/**
 *      gsm_fcs_add     -       update FCS
 *      @fcs: Current FCS
 *      @c: Next data
 *
 *      Update the FCS to include c. Uses the algorithm in the specification
 *      notes.
 */


static inline u8 gsm_fcs_add(u8 fcs, u8 c) { return gsm_fcs8[fcs ^ c]; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox21100.00%1100.00%
Total21100.00%1100.00%

/** * gsm_fcs_add_block - update FCS for a block * @fcs: Current FCS * @c: buffer of data * @len: length of buffer * * Update the FCS to include c. Uses the algorithm in the specification * notes. */
static inline u8 gsm_fcs_add_block(u8 fcs, u8 *c, int len) { while (len--) fcs = gsm_fcs8[fcs ^ *c++]; return fcs; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox36100.00%1100.00%
Total36100.00%1100.00%

/** * gsm_read_ea - read a byte into an EA * @val: variable holding value * c: byte going into the EA * * Processes one byte of an EA. Updates the passed variable * and returns 1 if the EA is now completely read */
static int gsm_read_ea(unsigned int *val, u8 c) { /* Add the next 7 bits into the value */ *val <<= 7; *val |= c >> 1; /* Was this the last byte of the EA 1 = yes*/ return c & EA; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox33100.00%1100.00%
Total33100.00%1100.00%

/** * gsm_encode_modem - encode modem data bits * @dlci: DLCI to encode from * * Returns the correct GSM encoded modem status bits (6 bit field) for * the current status of the DLCI and attached tty object */
static u8 gsm_encode_modem(const struct gsm_dlci *dlci) { u8 modembits = 0; /* FC is true flow control not modem bits */ if (dlci->throttled) modembits |= MDM_FC; if (dlci->modem_tx & TIOCM_DTR) modembits |= MDM_RTC; if (dlci->modem_tx & TIOCM_RTS) modembits |= MDM_RTR; if (dlci->modem_tx & TIOCM_RI) modembits |= MDM_IC; if (dlci->modem_tx & TIOCM_CD) modembits |= MDM_DV; return modembits; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox79100.00%1100.00%
Total79100.00%1100.00%

/** * gsm_print_packet - display a frame for debug * @hdr: header to print before decode * @addr: address EA from the frame * @cr: C/R bit from the frame * @control: control including PF bit * @data: following data bytes * @dlen: length of data * * Displays a packet in human readable format for debugging purposes. The * style is based on amateur radio LAP-B dump display. */
static void gsm_print_packet(const char *hdr, int addr, int cr, u8 control, const u8 *data, int dlen) { if (!(debug & 1)) return; pr_info("%s %d) %c: ", hdr, addr, "RC"[cr]); switch (control & ~PF) { case SABM: pr_cont("SABM"); break; case UA: pr_cont("UA"); break; case DISC: pr_cont("DISC"); break; case DM: pr_cont("DM"); break; case UI: pr_cont("UI"); break; case UIH: pr_cont("UIH"); break; default: if (!(control & 0x01)) { pr_cont("I N(S)%d N(R)%d", (control & 0x0E) >> 1, (control & 0xE0) >> 5); } else switch (control & 0x0F) { case RR: pr_cont("RR(%d)", (control & 0xE0) >> 5); break; case RNR: pr_cont("RNR(%d)", (control & 0xE0) >> 5); break; case REJ: pr_cont("REJ(%d)", (control & 0xE0) >> 5); break; default: pr_cont("[%02X]", control); } } if (control & PF) pr_cont("(P)"); else pr_cont("(F)"); if (dlen) { int ct = 0; while (dlen--) { if (ct % 8 == 0) { pr_cont("\n"); pr_debug(" "); } pr_cont("%02X ", *data++); ct++; } } pr_cont("\n"); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox288100.00%3100.00%
Total288100.00%3100.00%

/* * Link level transmission side */ /** * gsm_stuff_packet - bytestuff a packet * @ibuf: input * @obuf: output * @len: length of input * * Expand a buffer by bytestuffing it. The worst case size change * is doubling and the caller is responsible for handing out * suitable sized buffers. */
static int gsm_stuff_frame(const u8 *input, u8 *output, int len) { int olen = 0; while (len--) { if (*input == GSM1_SOF || *input == GSM1_ESCAPE || *input == XON || *input == XOFF) { *output++ = GSM1_ESCAPE; *output++ = *input++ ^ GSM1_ESCAPE_BITS; olen++; } else *output++ = *input++; olen++; } return olen; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox88100.00%1100.00%
Total88100.00%1100.00%

/** * gsm_send - send a control frame * @gsm: our GSM mux * @addr: address for control frame * @cr: command/response bit * @control: control byte including PF bit * * Format up and transmit a control frame. These do not go via the * queueing logic as they should be transmitted ahead of data when * they are needed. * * FIXME: Lock versus data TX path */
static void gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) { int len; u8 cbuf[10]; u8 ibuf[3]; switch (gsm->encoding) { case 0: cbuf[0] = GSM0_SOF; cbuf[1] = (addr << 2) | (cr << 1) | EA; cbuf[2] = control; cbuf[3] = EA; /* Length of data = 0 */ cbuf[4] = 0xFF - gsm_fcs_add_block(INIT_FCS, cbuf + 1, 3); cbuf[5] = GSM0_SOF; len = 6; break; case 1: case 2: /* Control frame + packing (but not frame stuffing) in mode 1 */ ibuf[0] = (addr << 2) | (cr << 1) | EA; ibuf[1] = control; ibuf[2] = 0xFF - gsm_fcs_add_block(INIT_FCS, ibuf, 2); /* Stuffing may double the size worst case */ len = gsm_stuff_frame(ibuf, cbuf + 1, 3); /* Now add the SOF markers */ cbuf[0] = GSM1_SOF; cbuf[len + 1] = GSM1_SOF; /* FIXME: we can omit the lead one in many cases */ len += 2; break; default: WARN_ON(1); return; } gsm->output(gsm, cbuf, len); gsm_print_packet("-->", addr, cr, control, NULL, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox236100.00%1100.00%
Total236100.00%1100.00%

/** * gsm_response - send a control response * @gsm: our GSM mux * @addr: address for control frame * @control: control byte including PF bit * * Format up and transmit a link level response frame. */
static inline void gsm_response(struct gsm_mux *gsm, int addr, int control) { gsm_send(gsm, addr, 0, control); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox29100.00%1100.00%
Total29100.00%1100.00%

/** * gsm_command - send a control command * @gsm: our GSM mux * @addr: address for control frame * @control: control byte including PF bit * * Format up and transmit a link level command frame. */
static inline void gsm_command(struct gsm_mux *gsm, int addr, int control) { gsm_send(gsm, addr, 1, control); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox29100.00%1100.00%
Total29100.00%1100.00%

/* Data transmission */ #define HDR_LEN 6 /* ADDR CTRL [LEN.2] DATA FCS */ /** * gsm_data_alloc - allocate data frame * @gsm: GSM mux * @addr: DLCI address * @len: length excluding header and FCS * @ctrl: control byte * * Allocate a new data buffer for sending frames with data. Space is left * at the front for header bytes but that is treated as an implementation * detail and not for the high level code to use */
static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, u8 ctrl) { struct gsm_msg *m = kmalloc(sizeof(struct gsm_msg) + len + HDR_LEN, GFP_ATOMIC); if (m == NULL) return NULL; m->data = m->buffer + HDR_LEN - 1; /* Allow for FCS */ m->len = len; m->addr = addr; m->ctrl = ctrl; INIT_LIST_HEAD(&m->list); return m; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox8894.62%150.00%
Russ Gorby55.38%150.00%
Total93100.00%2100.00%

/** * gsm_data_kick - poke the queue * @gsm: GSM Mux * * The tty device has called us to indicate that room has appeared in * the transmit queue. Ram more data into the pipe if we have any * If we have been flow-stopped by a CMD_FCOFF, then we can only * send messages on DLCI0 until CMD_FCON * * FIXME: lock against link layer control transmissions */
static void gsm_data_kick(struct gsm_mux *gsm) { struct gsm_msg *msg, *nmsg; int len; int skip_sof = 0; list_for_each_entry_safe(msg, nmsg, &gsm->tx_list, list) { if (gsm->constipated && msg->addr) continue; if (gsm->encoding != 0) { gsm->txframe[0] = GSM1_SOF; len = gsm_stuff_frame(msg->data, gsm->txframe + 1, msg->len); gsm->txframe[len + 1] = GSM1_SOF; len += 2; } else { gsm->txframe[0] = GSM0_SOF; memcpy(gsm->txframe + 1 , msg->data, msg->len); gsm->txframe[msg->len + 1] = GSM0_SOF; len = msg->len + 2; } if (debug & 4) print_hex_dump_bytes("gsm_data_kick: ", DUMP_PREFIX_OFFSET, gsm->txframe, len); if (gsm->output(gsm, gsm->txframe + skip_sof, len - skip_sof) < 0) break; /* FIXME: Can eliminate one SOF in many more cases */ gsm->tx_bytes -= msg->len; /* For a burst of frames skip the extra SOF within the burst */ skip_sof = 1; list_del(&msg->list); kfree(msg); } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox18081.45%125.00%
Russ Gorby188.14%125.00%
Frederic Berat188.14%125.00%
Joe Perches52.26%125.00%
Total221100.00%4100.00%

/** * __gsm_data_queue - queue a UI or UIH frame * @dlci: DLCI sending the data * @msg: message queued * * Add data to the transmit queue and try and get stuff moving * out of the mux tty if not already doing so. The Caller must hold * the gsm tx lock. */
static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) { struct gsm_mux *gsm = dlci->gsm; u8 *dp = msg->data; u8 *fcs = dp + msg->len; /* Fill in the header */ if (gsm->encoding == 0) { if (msg->len < 128) *--dp = (msg->len << 1) | EA; else { *--dp = (msg->len >> 7); /* bits 7 - 15 */ *--dp = (msg->len & 127) << 1; /* bits 0 - 6 */ } } *--dp = msg->ctrl; if (gsm->initiator) *--dp = (msg->addr << 2) | 2 | EA; else *--dp = (msg->addr << 2) | EA; *fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp); /* Ugly protocol layering violation */ if (msg->ctrl == UI || msg->ctrl == (UI|PF)) *fcs = gsm_fcs_add_block(*fcs, msg->data, msg->len); *fcs = 0xFF - *fcs; gsm_print_packet("Q> ", msg->addr, gsm->initiator, msg->ctrl, msg->data, msg->len); /* Move the header back and adjust the length, also allow for the FCS now tacked on the end */ msg->len += (msg->data - dp) + 1; msg->data = dp; /* Add to the actual output queue */ list_add_tail(&msg->list, &gsm->tx_list); gsm->tx_bytes += msg->len; gsm_data_kick(gsm); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox26894.04%125.00%
Ken Mills93.16%250.00%
Russ Gorby82.81%125.00%
Total285100.00%4100.00%

/** * gsm_data_queue - queue a UI or UIH frame * @dlci: DLCI sending the data * @msg: message queued * * Add data to the transmit queue and try and get stuff moving * out of the mux tty if not already doing so. Take the * the gsm tx lock and dlci lock. */
static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) { unsigned long flags; spin_lock_irqsave(&dlci->gsm->tx_lock, flags); __gsm_data_queue(dlci, msg); spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox51100.00%1100.00%
Total51100.00%1100.00%

/** * gsm_dlci_data_output - try and push data out of a DLCI * @gsm: mux * @dlci: the DLCI to pull data from * * Pull data from a DLCI and send it into the transmit queue if there * is data. Keep to the MRU of the mux. This path handles the usual tty * interface which is a byte stream with optional modem data. * * Caller must hold the tx_lock of the mux. */
static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) { struct gsm_msg *msg; u8 *dp; int len, total_size, size; int h = dlci->adaption - 1; total_size = 0; while (1) { len = kfifo_len(dlci->fifo); if (len == 0) return total_size; /* MTU/MRU count only the data bits */ if (len > gsm->mtu) len = gsm->mtu; size = len + h; msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); /* FIXME: need a timer or something to kick this so it can't get stuck with no work outstanding and no buffer free */ if (msg == NULL) return -ENOMEM; dp = msg->data; switch (dlci->adaption) { case 1: /* Unstructured */ break; case 2: /* Unstructed with modem bits. Always one byte as we never send inline break data */ *dp++ = gsm_encode_modem(dlci); break; } WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len); __gsm_data_queue(dlci, msg); total_size += size; } /* Bytes of data we used up */ return total_size; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox16588.24%125.00%
Mikhail Kshevetskiy2111.23%250.00%
Aldo Iljazi10.53%125.00%
Total187100.00%4100.00%

/** * gsm_dlci_data_output_framed - try and push data out of a DLCI * @gsm: mux * @dlci: the DLCI to pull data from * * Pull data from a DLCI and send it into the transmit queue if there * is data. Keep to the MRU of the mux. This path handles framed data * queued as skbuffs to the DLCI. * * Caller must hold the tx_lock of the mux. */
static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, struct gsm_dlci *dlci) { struct gsm_msg *msg; u8 *dp; int len, size; int last = 0, first = 0; int overhead = 0; /* One byte per frame is used for B/F flags */ if (dlci->adaption == 4) overhead = 1; /* dlci->skb is locked by tx_lock */ if (dlci->skb == NULL) { dlci->skb = skb_dequeue_tail(&dlci->skb_list); if (dlci->skb == NULL) return 0; first = 1; } len = dlci->skb->len + overhead; /* MTU/MRU count only the data bits */ if (len > gsm->mtu) { if (dlci->adaption == 3) { /* Over long frame, bin it */ dev_kfree_skb_any(dlci->skb); dlci->skb = NULL; return 0; } len = gsm->mtu; } else last = 1; size = len + overhead; msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); /* FIXME: need a timer or something to kick this so it can't get stuck with no work outstanding and no buffer free */ if (msg == NULL) { skb_queue_tail(&dlci->skb_list, dlci->skb); dlci->skb = NULL; return -ENOMEM; } dp = msg->data; if (dlci->adaption == 4) { /* Interruptible framed (Packetised Data) */ /* Flag byte to carry the start/end info */ *dp++ = last << 7 | first << 6 | 1; /* EA */ len--; } memcpy(dp, dlci->skb->data, len); skb_pull(dlci->skb, len); __gsm_data_queue(dlci, msg); if (last) { dev_kfree_skb_any(dlci->skb); dlci->skb = NULL; } return size; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox25686.78%120.00%
Russ Gorby3913.22%480.00%
Total295100.00%5100.00%

/** * gsm_dlci_data_sweep - look for data to send * @gsm: the GSM mux * * Sweep the GSM mux channels in priority order looking for ones with * data to send. We could do with optimising this scan a bit. We aim * to fill the queue totally or up to TX_THRESH_HI bytes. Once we hit * TX_THRESH_LO we get called again * * FIXME: We should round robin between groups and in theory you can * renegotiate DLCI priorities with optional stuff. Needs optimising. */
static void gsm_dlci_data_sweep(struct gsm_mux *gsm) { int len; /* Priority ordering: We should do priority with RR of the groups */ int i = 1; while (i < NUM_DLCI) { struct gsm_dlci *dlci; if (gsm->tx_bytes > TX_THRESH_HI) break; dlci = gsm->dlci[i]; if (dlci == NULL || dlci->constipated) { i++; continue; } if (dlci->adaption < 3 && !dlci->net) len = gsm_dlci_data_output(gsm, dlci); else len = gsm_dlci_data_output_framed(gsm, dlci); if (len < 0) break; /* DLCI empty - try the next */ if (len == 0) i++; } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox11094.83%133.33%
Russ Gorby54.31%133.33%
Julia Lawall10.86%133.33%
Total116100.00%3100.00%

/** * gsm_dlci_data_kick - transmit if possible * @dlci: DLCI to kick * * Transmit data from this DLCI if the queue is empty. We can't rely on * a tty wakeup except when we filled the pipe so we need to fire off * new data ourselves in other cases. */
static void gsm_dlci_data_kick(struct gsm_dlci *dlci) { unsigned long flags; int sweep; if (dlci->constipated) return; spin_lock_irqsave(&dlci->gsm->tx_lock, flags); /* If we have nothing running then we need to fire up */ sweep = (dlci->gsm->tx_bytes < TX_THRESH_LO); if (dlci->gsm->tx_bytes == 0) { if (dlci->net) gsm_dlci_data_output_framed(dlci->gsm, dlci); else gsm_dlci_data_output(dlci->gsm, dlci); } if (sweep) gsm_dlci_data_sweep(dlci->gsm); spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox6962.73%125.00%
Russ Gorby3430.91%250.00%
Frederic Berat76.36%125.00%
Total110100.00%4100.00%

/* * Control message processing */ /** * gsm_control_reply - send a response frame to a control * @gsm: gsm channel * @cmd: the command to use * @data: data to follow encoded info * @dlen: length of data * * Encode up and queue a UI/UIH frame containing our response. */
static void gsm_control_reply(struct gsm_mux *gsm, int cmd, u8 *data, int dlen) { struct gsm_msg *msg; msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); if (msg == NULL) return; msg->data[0] = (cmd & 0xFE) << 1 | EA; /* Clear C/R */ msg->data[1] = (dlen << 1) | EA; memcpy(msg->data + 2, data, dlen); gsm_data_queue(gsm->dlci[0], msg); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox10193.52%150.00%
Ken Mills76.48%150.00%
Total108100.00%2100.00%

/** * gsm_process_modem - process received modem status * @tty: virtual tty bound to the DLCI * @dlci: DLCI to affect * @modem: modem bits (full EA) * * Used when a modem control message or line state inline in adaption * layer 2 is processed. Sort out the local modem state and throttles */
static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, u32 modem, int clen) { int mlines = 0; u8 brk = 0; int fc; /* The modem status command can either contain one octet (v.24 signals) or two octets (v.24 signals + break signals). The length field will either be 2 or 3 respectively. This is specified in section 5.4.6.3.7 of the 27.010 mux spec. */ if (clen == 2) modem = modem & 0x7f; else { brk = modem & 0x7f; modem = (modem >> 7) & 0x7f; } /* Flow control/ready to communicate */ fc = (modem & MDM_FC) || !(modem & MDM_RTR); if (fc && !dlci->constipated) { /* Need to throttle our output on this device */ dlci->constipated = 1; } else if (!fc && dlci->constipated) { dlci->constipated = 0; gsm_dlci_data_kick(dlci); } /* Map modem bits */ if (modem & MDM_RTC) mlines |= TIOCM_DSR | TIOCM_DTR; if (modem & MDM_RTR) mlines |= TIOCM_RTS | TIOCM_CTS; if (modem & MDM_IC) mlines |= TIOCM_RI; if (modem & MDM_DV) mlines |= TIOCM_CD; /* Carrier drop -> hangup */ if (tty) { if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD)) if (!C_CLOCAL(tty)) tty_hangup(tty); } if (brk & 0x01) tty_insert_flip_char(&dlci->port, 0, TTY_BREAK); dlci->modem_rx = mlines; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox14663.20%120.00%
Frederic Berat4218.18%120.00%
Russ Gorby3515.15%120.00%
Jiri Slaby52.16%120.00%
Peter Hurley31.30%120.00%
Total231100.00%5100.00%

/** * gsm_control_modem - modem status received * @gsm: GSM channel * @data: data following command * @clen: command length * * We have received a modem status control message. This is used by * the GSM mux protocol to pass virtual modem line status and optionally * to indicate break signals. Unpack it, convert to Linux representation * and if need be stuff a break message down the tty. */
static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen) { unsigned int addr = 0; unsigned int modem = 0; unsigned int brk = 0; struct gsm_dlci *dlci; int len = clen; u8 *dp = data; struct tty_struct *tty; while (gsm_read_ea(&addr, *dp++) == 0) { len--; if (len == 0) return; } /* Must be at least one byte following the EA */ len--; if (len <= 0) return; addr >>= 1; /* Closed port, or invalid ? */ if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) return; dlci = gsm->dlci[addr]; while (gsm_read_ea(&modem, *dp++) == 0) { len--; if (len == 0) return; } len--; if (len > 0) { while (gsm_read_ea(&brk, *dp++) == 0) { len--; if (len == 0) return; } modem <<= 7; modem |= (brk & 0x7f); } tty = tty_port_tty_get(&dlci->port); gsm_process_modem(tty, dlci, modem, clen); if (tty) { tty_wakeup(tty); tty_kref_put(tty); } gsm_control_reply(gsm, CMD_MSC, data, clen); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox19477.29%133.33%
Lars Poeschel5521.91%133.33%
Russ Gorby20.80%133.33%
Total251100.00%3100.00%

/** * gsm_control_rls - remote line status * @gsm: GSM channel * @data: data bytes * @clen: data length * * The modem sends us a two byte message on the control channel whenever * it wishes to send us an error state from the virtual link. Stuff * this into the uplink tty if present */
static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen) { struct tty_port *port; unsigned int addr = 0; u8 bits; int len = clen; u8 *dp = data; while (gsm_read_ea(&addr, *dp++) == 0) { len--; if (len == 0) return; } /* Must be at least one byte following ea */ len--; if (len <= 0) return; addr >>= 1; /* Closed port, or invalid ? */ if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) return; /* No error ? */ bits = *dp; if ((bits & 1) == 0) return; port = &gsm->dlci[addr]->port; if (bits & 2) tty_insert_flip_char(port, 0, TTY_OVERRUN); if (bits & 4) tty_insert_flip_char(port, 0, TTY_PARITY); if (bits & 8) tty_insert_flip_char(port, 0, TTY_FRAME); tty_flip_buffer_push(port); gsm_control_reply(gsm, CMD_RLS, data, clen); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox18695.38%133.33%
Jiri Slaby94.62%266.67%
Total195100.00%3100.00%

static void gsm_dlci_begin_close(struct gsm_dlci *dlci); /** * gsm_control_message - DLCI 0 control processing * @gsm: our GSM mux * @command: the command EA * @data: data beyond the command/length EAs * @clen: length * * Input processor for control messages from the other end of the link. * Processes the incoming request and queues a response frame or an * NSC response if not supported */
static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, u8 *data, int clen) { u8 buf[1]; unsigned long flags; switch (command) { case CMD_CLD: { struct gsm_dlci *dlci = gsm->dlci[0]; /* Modem wishes to close down */ if (dlci) { dlci->dead = 1; gsm->dead = 1; gsm_dlci_begin_close(dlci); } } break; case CMD_TEST: /* Modem wishes to test, reply with the data */ gsm_control_reply(gsm, CMD_TEST, data, clen); break; case CMD_FCON: /* Modem can accept data again */ gsm->constipated = 0; gsm_control_reply(gsm, CMD_FCON, NULL, 0); /* Kick the link in case it is idling */ spin_lock_irqsave(&gsm->tx_lock, flags); gsm_data_kick(gsm); spin_unlock_irqrestore(&gsm->tx_lock, flags); break; case CMD_FCOFF: /* Modem wants us to STFU */ gsm->constipated = 1; gsm_control_reply(gsm, CMD_FCOFF, NULL, 0); break; case CMD_MSC: /* Out of band modem line change indicator for a DLCI */ gsm_control_modem(gsm, data, clen); break; case CMD_RLS: /* Out of band error reception for a DLCI */ gsm_control_rls(gsm, data, clen); break; case CMD_PSC: /* Modem wishes to enter power saving state */ gsm_control_reply(gsm, CMD_PSC, NULL, 0); break; /* Optional unsupported commands */ case CMD_PN: /* Parameter negotiation */ case CMD_RPN: /* Remote port negotiation */ case CMD_SNC: /* Service negotiation command */ default: /* Reply to bad commands with an NSC */ buf[0] = command; gsm_control_reply(gsm, CMD_NSC, buf, 1); break; } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox20885.25%125.00%
Russ Gorby249.84%125.00%
Frederic Berat104.10%125.00%
Lucas De Marchi20.82%125.00%
Total244100.00%4100.00%

/** * gsm_control_response - process a response to our control * @gsm: our GSM mux * @command: the command (response) EA * @data: data beyond the command/length EA * @clen: length * * Process a response to an outstanding command. We only allow a single * control message in flight so this is fairly easy. All the clean up * is done by the caller, we just update the fields, flag it as done * and return */
static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, u8 *data, int clen) { struct gsm_control *ctrl; unsigned long flags; spin_lock_irqsave(&gsm->control_lock, flags); ctrl = gsm->pending_cmd; /* Does the reply match our command */ command |= 1; if (ctrl != NULL && (command == ctrl->cmd || command == CMD_NSC)) { /* Our command was replied to, kill the retry timer */ del_timer(&gsm->t2_timer); gsm->pending_cmd = NULL; /* Rejected by the other end */ if (command == CMD_NSC) ctrl->error = -EOPNOTSUPP; ctrl->done = 1; wake_up(&gsm->event); } spin_unlock_irqrestore(&gsm->control_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox125100.00%1100.00%
Total125100.00%1100.00%

/** * gsm_control_transmit - send control packet * @gsm: gsm mux * @ctrl: frame to send * * Send out a pending control command (called under control lock) */
static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl) { struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, gsm->ftype); if (msg == NULL) return; msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */ memcpy(msg->data + 1, ctrl->data, ctrl->len); gsm_data_queue(gsm->dlci[0], msg); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox94100.00%1100.00%
Total94100.00%1100.00%

/** * gsm_control_retransmit - retransmit a control frame * @data: pointer to our gsm object * * Called off the T2 timer expiry in order to retransmit control frames * that have been lost in the system somewhere. The control_lock protects * us from colliding with another sender or a receive completion event. * In that situation the timer may still occur in a small window but * gsm->pending_cmd will be NULL and we just let the timer expire. */
static void gsm_control_retransmit(unsigned long data) { struct gsm_mux *gsm = (struct gsm_mux *)data; struct gsm_control *ctrl; unsigned long flags; spin_lock_irqsave(&gsm->control_lock, flags); ctrl = gsm->pending_cmd; if (ctrl) { gsm->cretries--; if (gsm->cretries == 0) { gsm->pending_cmd = NULL; ctrl->error = -ETIMEDOUT; ctrl->done = 1; spin_unlock_irqrestore(&gsm->control_lock, flags); wake_up(&gsm->event); return; } gsm_control_transmit(gsm, ctrl); mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); } spin_unlock_irqrestore(&gsm->control_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox141100.00%1100.00%
Total141100.00%1100.00%

/** * gsm_control_send - send a control frame on DLCI 0 * @gsm: the GSM channel * @command: command to send including CR bit * @data: bytes of data (must be kmalloced) * @len: length of the block to send * * Queue and dispatch a control command. Only one command can be * active at a time. In theory more can be outstanding but the matching * gets really complicated so for now stick to one outstanding. */
static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, unsigned int command, u8 *data, int clen) { struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control), GFP_KERNEL); unsigned long flags; if (ctrl == NULL) return NULL; retry: wait_event(gsm->event, gsm->pending_cmd == NULL); spin_lock_irqsave(&gsm->control_lock, flags); if (gsm->pending_cmd != NULL) { spin_unlock_irqrestore(&gsm->control_lock, flags); goto retry; } ctrl->cmd = command; ctrl->data = data; ctrl->len = clen; gsm->pending_cmd = ctrl; gsm->cretries = gsm->n2; mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); gsm_control_transmit(gsm, ctrl); spin_unlock_irqrestore(&gsm->control_lock, flags); return ctrl; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox171100.00%1100.00%
Total171100.00%1100.00%

/** * gsm_control_wait - wait for a control to finish * @gsm: GSM mux * @control: control we are waiting on * * Waits for the control to complete or time out. Frees any used * resources and returns 0 for success, or an error if the remote * rejected or ignored the request. */
static int gsm_control_wait(struct gsm_mux *gsm, struct gsm_control *control) { int err; wait_event(gsm->event, control->done == 1); err = control->error; kfree(control); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox46100.00%1100.00%
Total46100.00%1100.00%

/* * DLCI level handling: Needs krefs */ /* * State transitions and timers */ /** * gsm_dlci_close - a DLCI has closed * @dlci: DLCI that closed * * Perform processing when moving a DLCI into closed state. If there * is an attached tty this is hung up */
static void gsm_dlci_close(struct gsm_dlci *dlci) { del_timer(&dlci->t1); if (debug & 8) pr_debug("DLCI %d goes closed.\n", dlci->addr); dlci->state = DLCI_CLOSED; if (dlci->addr != 0) { tty_port_tty_hangup(&dlci->port, false); kfifo_reset(dlci->fifo); } else dlci->gsm->dead = 1; wake_up(&dlci->gsm->event); /* A DLCI 0 close is a MUX termination so we need to kick that back to userspace somehow */ }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox8496.55%266.67%
Jiri Slaby33.45%133.33%
Total87100.00%3100.00%

/** * gsm_dlci_open - a DLCI has opened * @dlci: DLCI that opened * * Perform processing when moving a DLCI into open state. */
static void gsm_dlci_open(struct gsm_dlci *dlci) { /* Note that SABM UA .. SABM UA first UA lost can mean that we go open -> open */ del_timer(&dlci->t1); /* This will let a tty open continue */ dlci->state = DLCI_OPEN; if (debug & 8) pr_debug("DLCI %d goes open.\n", dlci->addr); wake_up(&dlci->gsm->event); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox52100.00%2100.00%
Total52100.00%2100.00%

/** * gsm_dlci_t1 - T1 timer expiry * @dlci: DLCI that opened * * The T1 timer handles retransmits of control frames (essentially of * SABM and DISC). We resend the command until the retry count runs out * in which case an opening port goes back to closed and a closing port * is simply put into closed state (any further frames from the other * end will get a DM response) */
static void gsm_dlci_t1(unsigned long data) { struct gsm_dlci *dlci = (struct gsm_dlci *)data; struct gsm_mux *gsm = dlci->gsm; switch (dlci->state) { case DLCI_OPENING: dlci->retries--; if (dlci->retries) { gsm_command(dlci->gsm, dlci->addr, SABM|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); } else gsm_dlci_close(dlci); break; case DLCI_CLOSING: dlci->retries--; if (dlci->retries) { gsm_command(dlci->gsm, dlci->addr, DISC|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); } else gsm_dlci_close(dlci); break; } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox151100.00%1100.00%
Total151100.00%1100.00%

/** * gsm_dlci_begin_open - start channel open procedure * @dlci: DLCI to open * * Commence opening a DLCI from the Linux side. We issue SABM messages * to the modem which should then reply with a UA, at which point we * will move into open state. Opening is done asynchronously with retry * running off timers and the responses. */
static void gsm_dlci_begin_open(struct gsm_dlci *dlci) { struct gsm_mux *gsm = dlci->gsm; if (dlci->state == DLCI_OPEN || dlci->state == DLCI_OPENING) return; dlci->retries = gsm->n2; dlci->state = DLCI_OPENING; gsm_command(dlci->gsm, dlci->addr, SABM|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox82100.00%1100.00%
Total82100.00%1100.00%

/** * gsm_dlci_begin_close - start channel open procedure * @dlci: DLCI to open * * Commence closing a DLCI from the Linux side. We issue DISC messages * to the modem which should then reply with a UA, at which point we * will move into closed state. Closing is done asynchronously with retry * off timers. We may also receive a DM reply from the other end which * indicates the channel was already closed. */
static void gsm_dlci_begin_close(struct gsm_dlci *dlci) { struct gsm_mux *gsm = dlci->gsm; if (dlci->state == DLCI_CLOSED || dlci->state == DLCI_CLOSING) return; dlci->retries = gsm->n2; dlci->state = DLCI_CLOSING; gsm_command(dlci->gsm, dlci->addr, DISC|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox82100.00%1100.00%
Total82100.00%1100.00%

/** * gsm_dlci_data - data arrived * @dlci: channel * @data: block of bytes received * @len: length of received block * * A UI or UIH frame has arrived which contains data for a channel * other than the control channel. If the relevant virtual tty is * open we shovel the bits down it, if not we drop them. */
static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int clen) { /* krefs .. */ struct tty_port *port = &dlci->port; struct tty_struct *tty; unsigned int modem = 0; int len = clen; if (debug & 16) pr_debug("%d bytes for tty\n", len); switch (dlci->adaption) { /* Unsupported types */ /* Packetised interruptible data */ case 4: break; /* Packetised uininterruptible voice/data */ case 3: break; /* Asynchronous serial with line state in each frame */ case 2: while (gsm_read_ea(&modem, *data++) == 0) { len--; if (len == 0) return; } tty = tty_port_tty_get(port); if (tty) { gsm_process_modem(tty, dlci, modem, clen); tty_kref_put(tty); } /* Line state will go via DLCI 0 controls only */ case 1: default: tty_insert_flip_string(port, data, len); tty_flip_buffer_push(port); } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox12681.29%240.00%
Jiri Slaby2113.55%240.00%
Russ Gorby85.16%120.00%
Total155100.00%5100.00%

/** * gsm_dlci_control - data arrived on control channel * @dlci: channel * @data: block of bytes received * @len: length of received block * * A UI or UIH frame has arrived which contains data for DLCI 0 the * control channel. This should contain a command EA followed by * control data bytes. The command EA contains a command/response bit * and we divide up the work accordingly. */
static void gsm_dlci_command(struct gsm_dlci *dlci, u8 *data, int len) { /* See what command is involved */ unsigned int command = 0; while (len-- > 0) { if (gsm_read_ea(&command, *data++) == 1) { int clen = *data++; len--; /* FIXME: this is properly an EA */ clen >>= 1; /* Malformed command ? */ if (clen > len) return; if (command & 1) gsm_control_message(dlci->gsm, command, data, clen); else gsm_control_response(dlci->gsm, command, data, clen); return; } } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox107100.00%1100.00%
Total107100.00%1100.00%

/* * Allocate/Free DLCI channels */ /** * gsm_dlci_alloc - allocate a DLCI * @gsm: GSM mux * @addr: address of the DLCI * * Allocate and install a new DLCI object into the GSM mux. * * FIXME: review locking races */
static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr) { struct gsm_dlci *dlci = kzalloc(sizeof(struct gsm_dlci), GFP_ATOMIC); if (dlci == NULL) return NULL; spin_lock_init(&dlci->lock); mutex_init(&dlci->mutex); dlci->fifo = &dlci->_fifo; if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) { kfree(dlci); return NULL; } skb_queue_head_init(&dlci->skb_list); init_timer(&dlci->t1); dlci->t1.function = gsm_dlci_t1; dlci->t1.data = (unsigned long)dlci; tty_port_init(&dlci->port); dlci->port.ops = &gsm_port_ops; dlci->gsm = gsm; dlci->addr = addr; dlci->adaption = gsm->adaption; dlci->state = DLCI_CLOSED; if (addr) dlci->data = gsm_dlci_data; else dlci->data = gsm_dlci_command; gsm->dlci[addr] = dlci; return dlci; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox19296.00%150.00%
Russ Gorby84.00%150.00%
Total200100.00%2100.00%

/** * gsm_dlci_free - free DLCI * @dlci: DLCI to free * * Free up a DLCI. * * Can sleep. */
static void gsm_dlci_free(struct tty_port *port) { struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); del_timer_sync(&dlci->t1); dlci->gsm->dlci[dlci->addr] = NULL; kfifo_free(dlci->fifo); while ((dlci->skb = skb_dequeue(&dlci->skb_list))) dev_kfree_skb(dlci->skb); kfree(dlci); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox4858.54%125.00%
Russ Gorby3036.59%250.00%
Jiri Slaby44.88%125.00%
Total82100.00%4100.00%


static inline void dlci_get(struct gsm_dlci *dlci) { tty_port_get(&dlci->port); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby1890.00%150.00%
Jiri Slaby210.00%150.00%
Total20100.00%2100.00%


static inline void dlci_put(struct gsm_dlci *dlci) { tty_port_put(&dlci->port); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby1890.00%150.00%
Jiri Slaby210.00%150.00%
Total20100.00%2100.00%

static void gsm_destroy_network(struct gsm_dlci *dlci); /** * gsm_dlci_release - release DLCI * @dlci: DLCI to destroy * * Release a DLCI. Actual free is deferred until either * mux is closed or tty is closed - whichever is last. * * Can sleep. */
static void gsm_dlci_release(struct gsm_dlci *dlci) { struct tty_struct *tty = tty_port_tty_get(&dlci->port); if (tty) { mutex_lock(&dlci->mutex); gsm_destroy_network(dlci); mutex_unlock(&dlci->mutex); tty_vhangup(tty); tty_port_tty_set(&dlci->port, NULL); tty_kref_put(tty); } dlci->state = DLCI_CLOSED; dlci_put(dlci); }

Contributors

PersonTokensPropCommitsCommitProp
Dirkjan Bussink3745.12%133.33%
Russ Gorby3441.46%133.33%
Alan Cox1113.41%133.33%
Total82100.00%3100.00%

/* * LAPBish link layer logic */ /** * gsm_queue - a GSM frame is ready to process * @gsm: pointer to our gsm mux * * At this point in time a frame has arrived and been demangled from * the line encoding. All the differences between the encodings have * been handled below us and the frame is unpacked into the structures. * The fcs holds the header FCS but any data FCS must be added here. */
static void gsm_queue(struct gsm_mux *gsm) { struct gsm_dlci *dlci; u8 cr; int address; /* We have to sneak a look at the packet body to do the FCS. A somewhat layering violation in the spec */ if ((gsm->control & ~PF) == UI) gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len); if (gsm->encoding == 0) { /* WARNING: gsm->received_fcs is used for gsm->encoding = 0 only. In this case it contain the last piece of data required to generate final CRC */ gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs); } if (gsm->fcs != GOOD_FCS) { gsm->bad_fcs++; if (debug & 4) pr_debug("BAD FCS %02x\n", gsm->fcs); return; } address = gsm->address >> 1; if (address >= NUM_DLCI) goto invalid; cr = gsm->address & 1; /* C/R bit */ gsm_print_packet("<--", address, cr, gsm->control, gsm->buf, gsm->len); cr ^= 1 - gsm->initiator; /* Flip so 1 always means command */ dlci = gsm->dlci[address]; switch (gsm->control) { case SABM|PF: if (cr == 0) goto invalid; if (dlci == NULL) dlci = gsm_dlci_alloc(gsm, address); if (dlci == NULL) return; if (dlci->dead) gsm_response(gsm, address, DM); else { gsm_response(gsm, address, UA); gsm_dlci_open(dlci); } break; case DISC|PF: if (cr == 0) goto invalid; if (dlci == NULL || dlci->state == DLCI_CLOSED) { gsm_response(gsm, address, DM); return; } /* Real close complete */ gsm_response(gsm, address, UA); gsm_dlci_close(dlci); break; case UA: case UA|PF: if (cr == 0 || dlci == NULL) break; switch (dlci->state) { case DLCI_CLOSING: gsm_dlci_close(dlci); break; case DLCI_OPENING: gsm_dlci_open(dlci); break; } break; case DM: /* DM can be valid unsolicited */ case DM|PF: if (cr) goto invalid; if (dlci == NULL) return; gsm_dlci_close(dlci); break; case UI: case UI|PF: case UIH: case UIH|PF: #if 0 if (cr) goto invalid; #endif if (dlci == NULL || dlci->state != DLCI_OPEN) { gsm_command(gsm, address, DM|PF); return; } dlci->data(dlci, gsm->buf, gsm->len); break; default: goto invalid; } return; invalid: gsm->malformed++; return; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox44997.61%360.00%
Mikhail Kshevetskiy102.17%120.00%
Aldo Iljazi10.22%120.00%
Total460100.00%5100.00%

/** * gsm0_receive - perform processing for non-transparency * @gsm: gsm data for this ldisc instance * @c: character * * Receive bytes in gsm mode 0 */
static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) { unsigned int len; switch (gsm->state) { case GSM_SEARCH: /* SOF marker */ if (c == GSM0_SOF) { gsm->state = GSM_ADDRESS; gsm->address = 0; gsm->len = 0; gsm->fcs = INIT_FCS; } break; case GSM_ADDRESS: /* Address EA */ gsm->fcs = gsm_fcs_add(gsm->fcs, c); if (gsm_read_ea(&gsm->address, c)) gsm->state = GSM_CONTROL; break; case GSM_CONTROL: /* Control Byte */ gsm->fcs = gsm_fcs_add(gsm->fcs, c); gsm->control = c; gsm->state = GSM_LEN0; break; case GSM_LEN0: /* Length EA */ gsm->fcs = gsm_fcs_add(gsm->fcs, c); if (gsm_read_ea(&gsm->len, c)) { if (gsm->len > gsm->mru) { gsm->bad_size++; gsm->state = GSM_SEARCH; break; } gsm->count = 0; if (!gsm->len) gsm->state = GSM_FCS; else gsm->state = GSM_DATA; break; } gsm->state = GSM_LEN1; break; case GSM_LEN1: gsm->fcs = gsm_fcs_add(gsm->fcs, c); len = c; gsm->len |= len << 7; if (gsm->len > gsm->mru) { gsm->bad_size++; gsm->state = GSM_SEARCH; break; } gsm->count = 0; if (!gsm->len) gsm->state = GSM_FCS; else gsm->state = GSM_DATA; break; case GSM_DATA: /* Data */ gsm->buf[gsm->count++] = c; if (gsm->count == gsm->len) gsm->state = GSM_FCS; break; case GSM_FCS: /* FCS follows the packet */ gsm->received_fcs = c; gsm_queue(gsm); gsm->state = GSM_SSOF; break; case GSM_SSOF: if (c == GSM0_SOF) { gsm->state = GSM_SEARCH; break; } break; } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox372100.00%2100.00%
Total372100.00%2100.00%

/** * gsm1_receive - perform processing for non-transparency * @gsm: gsm data for this ldisc instance * @c: character * * Receive bytes in mode 1 (Advanced option) */
static void gsm1_receive(struct gsm_mux *gsm, unsigned char c) { if (c == GSM1_SOF) { /* EOF is only valid in frame if we have got to the data state and received at least one byte (the FCS) */ if (gsm->state == GSM_DATA && gsm->count) { /* Extract the FCS */ gsm->count--; gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->buf[gsm->count]); gsm->len = gsm->count; gsm_queue(gsm); gsm->state = GSM_START; return; } /* Any partial frame was a runt so go back to start */ if (gsm->state != GSM_START) { gsm->malformed++; gsm->state = GSM_START; } /* A SOF in GSM_START means we are still reading idling or framing bytes */ return; } if (c == GSM1_ESCAPE) { gsm->escape = 1; return; } /* Only an unescaped SOF gets us out of GSM search */ if (gsm->state == GSM_SEARCH) return; if (gsm->escape) { c ^= GSM1_ESCAPE_BITS; gsm->escape = 0; } switch (gsm->state) { case GSM_START: /* First byte after SOF */ gsm->address = 0; gsm->state = GSM_ADDRESS; gsm->fcs = INIT_FCS; /* Drop through */ case GSM_ADDRESS: /* Address continuation */ gsm->fcs = gsm_fcs_add(gsm->fcs, c); if (gsm_read_ea(&gsm->address, c)) gsm->state = GSM_CONTROL; break; case GSM_CONTROL: /* Control Byte */ gsm->fcs = gsm_fcs_add(gsm->fcs, c); gsm->control = c; gsm->count = 0; gsm->state = GSM_DATA; break; case GSM_DATA: /* Data */ if (gsm->count > gsm->mru) { /* Allow one for the FCS */ gsm->state = GSM_OVERRUN; gsm->bad_size++; } else gsm->buf[gsm->count++] = c; break; case GSM_OVERRUN: /* Over-long - eg a dropped SOF */ break; } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox301100.00%1100.00%
Total301100.00%1100.00%

/** * gsm_error - handle tty error * @gsm: ldisc data * @data: byte received (may be invalid) * @flag: error received * * Handle an error in the receipt of data for a frame. Currently we just * go back to hunting for a SOF. * * FIXME: better diagnostics ? */
static void gsm_error(struct gsm_mux *gsm, unsigned char data, unsigned char flag) { gsm->state = GSM_SEARCH; gsm->io_error++; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox30100.00%1100.00%
Total30100.00%1100.00%


static int gsm_disconnect(struct gsm_mux *gsm) { struct gsm_dlci *dlci = gsm->dlci[0]; struct gsm_control *gc; if (!dlci) return 0; /* In theory disconnecting DLCI 0 is sufficient but for some modems this is apparently not the case. */ gc = gsm_control_send(gsm, CMD_CLD, NULL, 0); if (gc) gsm_control_wait(gsm, gc); del_timer_sync(&gsm->t2_timer); /* Now we are sure T2 has stopped */ gsm_dlci_begin_close(dlci); wait_event_interruptible(gsm->event, dlci->state == DLCI_CLOSED); if (signal_pending(current)) return -EINTR; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sascha Hauer102100.00%1100.00%
Total102100.00%1100.00%

/** * gsm_cleanup_mux - generic GSM protocol cleanup * @gsm: our mux * * Clean up the bits of the mux which are the same for all framing * protocols. Remove the mux from the mux table, stop all the timers * and then shut down each device hanging up the channels as we go. */
static void gsm_cleanup_mux(struct gsm_mux *gsm) { int i; struct gsm_dlci *dlci = gsm->dlci[0]; struct gsm_msg *txq, *ntxq; gsm->dead = 1; spin_lock(&gsm_mux_lock); for (i = 0; i < MAX_MUX; i++) { if (gsm_mux[i] == gsm) { gsm_mux[i] = NULL; break; } } spin_unlock(&gsm_mux_lock); /* open failed before registering => nothing to do */ if (i == MAX_MUX) return; del_timer_sync(&gsm->t2_timer); /* Now we are sure T2 has stopped */ if (dlci) dlci->dead = 1; /* Free up any link layer users */ mutex_lock(&gsm->mutex); for (i = 0; i < NUM_DLCI; i++) if (gsm->dlci[i]) gsm_dlci_release(gsm->dlci[i]); mutex_unlock(&gsm->mutex); /* Now wipe the queues */ list_for_each_entry_safe(txq, ntxq, &gsm->tx_list, list) kfree(txq); INIT_LIST_HEAD(&gsm->tx_list); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox14577.96%114.29%
Russ Gorby1910.22%342.86%
Chao Bi168.60%114.29%
Jiri Slaby52.69%114.29%
Rashika Kheria10.54%114.29%
Total186100.00%7100.00%

/** * gsm_activate_mux - generic GSM setup * @gsm: our mux * * Set up the bits of the mux which are the same for all framing * protocols. Add the mux to the mux table so it can be opened and * finally kick off connecting to DLCI 0 on the modem. */
static int gsm_activate_mux(struct gsm_mux *gsm) { struct gsm_dlci *dlci; int i = 0; setup_timer(&gsm->t2_timer, gsm_control_retransmit, (unsigned long)gsm); init_waitqueue_head(&gsm->event); spin_lock_init(&gsm->control_lock); spin_lock_init(&gsm->tx_lock); if (gsm->encoding == 0) gsm->receive = gsm0_receive; else gsm->receive = gsm1_receive; gsm->error = gsm_error; spin_lock(&gsm_mux_lock); for (i = 0; i < MAX_MUX; i++) { if (gsm_mux[i] == NULL) { gsm->num = i; gsm_mux[i] = gsm; break; } } spin_unlock(&gsm_mux_lock); if (i == MAX_MUX) return -EBUSY; dlci = gsm_dlci_alloc(gsm, 0); if (dlci == NULL) return -ENOMEM; gsm->dead = 0; /* Tty opens are now permissible */ return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox16893.85%125.00%
Russ Gorby63.35%125.00%
Jiri Slaby42.23%125.00%
Rashika Kheria10.56%125.00%
Total179100.00%4100.00%

/** * gsm_free_mux - free up a mux * @mux: mux to free * * Dispose of allocated resources for a dead mux */
static void gsm_free_mux(struct gsm_mux *gsm) { kfree(gsm->txframe); kfree(gsm->buf); kfree(gsm); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox2996.67%150.00%
Rashika Kheria13.33%150.00%
Total30100.00%2100.00%

/** * gsm_free_muxr - free up a mux * @mux: mux to free * * Dispose of allocated resources for a dead mux */
static void gsm_free_muxr(struct kref *ref) { struct gsm_mux *gsm = container_of(ref, struct gsm_mux, ref); gsm_free_mux(gsm); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby31100.00%1100.00%
Total31100.00%1100.00%


static inline void mux_get(struct gsm_mux *gsm) { kref_get(&gsm->ref); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby20100.00%1100.00%
Total20100.00%1100.00%


static inline void mux_put(struct gsm_mux *gsm) { kref_put(&gsm->ref, gsm_free_muxr); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby22100.00%1100.00%
Total22100.00%1100.00%

/** * gsm_alloc_mux - allocate a mux * * Creates a new mux ready for activation. */
static struct gsm_mux *gsm_alloc_mux(void) { struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL); if (gsm == NULL) return NULL; gsm->buf = kmalloc(MAX_MRU + 1, GFP_KERNEL); if (gsm->buf == NULL) { kfree(gsm); return NULL; } gsm->txframe = kmalloc(2 * MAX_MRU + 2, GFP_KERNEL); if (gsm->txframe == NULL) { kfree(gsm->buf); kfree(gsm); return NULL; } spin_lock_init(&gsm->lock); mutex_init(&gsm->mutex); kref_init(&gsm->ref); INIT_LIST_HEAD(&gsm->tx_list); gsm->t1 = T1; gsm->t2 = T2; gsm->n2 = N2; gsm->ftype = UIH; gsm->adaption = 1; gsm->encoding = 1; gsm->mru = 64; /* Default to encoding 1 so these should be 64 */ gsm->mtu = 64; gsm->dead = 1; /* Avoid early tty opens */ return gsm; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox17287.31%120.00%
Russ Gorby168.12%240.00%
Chao Bi84.06%120.00%
Rashika Kheria10.51%120.00%
Total197100.00%5100.00%

/** * gsmld_output - write to link * @gsm: our mux * @data: bytes to output * @len: size * * Write a block of data from the GSM mux to the data channel. This * will eventually be serialized from above but at the moment isn't. */
static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) { if (tty_write_room(gsm->tty) < len) { set_bit(TTY_DO_WRITE_WAKEUP, &gsm->tty->flags); return -ENOSPC; } if (debug & 4) print_hex_dump_bytes("gsmld_output: ", DUMP_PREFIX_OFFSET, data, len); gsm->tty->ops->write(gsm->tty, data, len); return len; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox8095.24%150.00%
Joe Perches44.76%150.00%
Total84100.00%2100.00%

/** * gsmld_attach_gsm - mode set up * @tty: our tty structure * @gsm: our mux * * Set up the MUX for basic mode and commence connecting to the * modem. Currently called from the line discipline set up but * will need moving to an ioctl path. */
static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) { int ret, i, base; gsm->tty = tty_kref_get(tty); gsm->output = gsmld_output; ret = gsm_activate_mux(gsm); if (ret != 0) tty_kref_put(gsm->tty); else { /* Don't register device 0 - this is the control channel and not a usable tty interface */ base = gsm->num << 6; /* Base for this MUX */ for (i = 1; i < NUM_DLCI; i++) tty_register_device(gsm_tty_driver, base + i, NULL); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox5758.16%133.33%
Russ Gorby3131.63%133.33%
Pan Xinhui1010.20%133.33%
Total98100.00%3100.00%

/** * gsmld_detach_gsm - stop doing 0710 mux * @tty: tty attached to the mux * @gsm: mux * * Shutdown and then clean up the resources used by the line discipline */
static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) { int i; int base = gsm->num << 6; /* Base for this MUX */ WARN_ON(tty != gsm->tty); for (i = 1; i < NUM_DLCI; i++) tty_unregister_device(gsm_tty_driver, base + i); gsm_cleanup_mux(gsm); tty_kref_put(gsm->tty); gsm->tty = NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox4355.13%150.00%
Russ Gorby3544.87%150.00%
Total78100.00%2100.00%


static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) { struct gsm_mux *gsm = tty->disc_data; const unsigned char *dp; char *f; int i; char flags = TTY_NORMAL; if (debug & 4) print_hex_dump_bytes("gsmld_receive: ", DUMP_PREFIX_OFFSET, cp, count); for (i = count, dp = cp, f = fp; i; i--, dp++) { if (f) flags = *f++; switch (flags) { case TTY_NORMAL: gsm->receive(gsm, *dp); break; case TTY_OVERRUN: case TTY_BREAK: case TTY_PARITY: case TTY_FRAME: gsm->error(gsm, *dp, flags); break; default: WARN_ONCE(1, "%s: unknown flag %d\n", tty_name(tty), flags); break; } } /* FASYNC if needed ? */ /* If clogged call tty_throttle(tty); */ }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox15292.12%233.33%
Peter Hurley63.64%116.67%
Joe Perches42.42%116.67%
Frederic Berat21.21%116.67%
Linus Torvalds10.61%116.67%
Total165100.00%6100.00%

/** * gsmld_flush_buffer - clean input queue * @tty: terminal device * * Flush the input buffer. Called when the line discipline is * being closed, when the tty layer wants the buffer flushed (eg * at hangup). */
static void gsmld_flush_buffer(struct tty_struct *tty) { }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox10100.00%1100.00%
Total10100.00%1100.00%

/** * gsmld_close - close the ldisc for this tty * @tty: device * * Called from the terminal layer when this line discipline is * being shut down, either because of a close or becsuse of a * discipline change. The function will not be called while other * ldisc methods are in progress. */
static void gsmld_close(struct tty_struct *tty) { struct gsm_mux *gsm = tty->disc_data; gsmld_detach_gsm(tty, gsm); gsmld_flush_buffer(tty); /* Do other clean up here */ mux_put(gsm); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox3797.37%150.00%
Russ Gorby12.63%150.00%
Total38100.00%2100.00%

/** * gsmld_open - open an ldisc * @tty: terminal to open * * Called when this line discipline is being attached to the * terminal device. Can sleep. Called serialized so that no * other events will occur in parallel. No further open will occur * until a close. */
static int gsmld_open(struct tty_struct *tty) { struct gsm_mux *gsm; int ret; if (tty->ops->write == NULL) return -EINVAL; /* Attach our ldisc data */ gsm = gsm_alloc_mux(); if (gsm == NULL) return -ENOMEM; tty->disc_data = gsm; tty->receive_room = 65536; /* Attach the initial passive connection */ gsm->encoding = 1; ret = gsmld_attach_gsm(tty, gsm); if (ret != 0) { gsm_cleanup_mux(gsm); mux_put(gsm); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox7273.47%150.00%
Pan Xinhui2626.53%150.00%
Total98100.00%2100.00%

/** * gsmld_write_wakeup - asynchronous I/O notifier * @tty: tty device * * Required for the ptys, serial driver etc. since processes * that attach themselves to the master and rely on ASYNC * IO must be woken up */
static void gsmld_write_wakeup(struct tty_struct *tty) { struct gsm_mux *gsm = tty->disc_data; unsigned long flags; /* Queue poll */ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); spin_lock_irqsave(&gsm->tx_lock, flags); gsm_data_kick(gsm); if (gsm->tx_bytes < TX_THRESH_LO) { gsm_dlci_data_sweep(gsm); } spin_unlock_irqrestore(&gsm->tx_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox4864.00%133.33%
Dan Carpenter1621.33%133.33%
Russ Gorby1114.67%133.33%
Total75100.00%3100.00%

/** * gsmld_read - read function for tty * @tty: tty device * @file: file object * @buf: userspace buffer pointer * @nr: size of I/O * * Perform reads for the line discipline. We are guaranteed that the * line discipline will not be closed under us but we may get multiple * parallel readers and must handle this ourselves. We may also get * a hangup. Always called in user context, may sleep. * * This code must be sure never to sleep through a hangup. */
static ssize_t gsmld_read(struct tty_struct *tty, struct file *file, unsigned char __user *buf, size_t nr) { return -EOPNOTSUPP; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox29100.00%1100.00%
Total29100.00%1100.00%

/** * gsmld_write - write function for tty * @tty: tty device * @file: file object * @buf: userspace buffer pointer * @nr: size of I/O * * Called when the owner of the device wants to send a frame * itself (or some other control data). The data is transferred * as-is and must be properly framed and checksummed as appropriate * by userspace. Frames are either sent whole or not at all as this * avoids pain user side. */
static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, const unsigned char *buf, size_t nr) { int space = tty_write_room(tty); if (space >= nr) return tty->ops->write(tty, buf, nr); set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); return -ENOBUFS; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox67100.00%1100.00%
Total67100.00%1100.00%

/** * gsmld_poll - poll method for N_GSM0710 * @tty: terminal device * @file: file accessing it * @wait: poll table * * Called when the line discipline is asked to poll() for data or * for special events. This code is not serialized with respect to * other events save open/close. * * This code must be sure never to sleep through a hangup. * Called without the kernel lock held - fine */
static unsigned int gsmld_poll(struct tty_struct *tty, struct file *file, poll_table *wait) { unsigned int mask = 0; struct gsm_mux *gsm = tty->disc_data; poll_wait(file, &tty->read_wait, wait); poll_wait(file, &tty->write_wait, wait); if (tty_hung_up_p(file)) mask |= POLLHUP; if (!tty_is_writelocked(tty) && tty_write_room(tty) > 0) mask |= POLLOUT | POLLWRNORM; if (gsm->dead) mask |= POLLHUP; return mask; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox105100.00%1100.00%
Total105100.00%1100.00%


static int gsmld_config(struct tty_struct *tty, struct gsm_mux *gsm, struct gsm_config *c) { int need_close = 0; int need_restart = 0; /* Stuff we don't support yet - UI or I frame transport, windowing */ if ((c->adaption != 1 && c->adaption != 2) || c->k) return -EOPNOTSUPP; /* Check the MRU/MTU range looks sane */ if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8) return -EINVAL; if (c->n2 < 3) return -EINVAL; if (c->encapsulation > 1) /* Basic, advanced, no I */ return -EINVAL; if (c->initiator > 1) return -EINVAL; if (c->i == 0 || c->i > 2) /* UIH and UI only */ return -EINVAL; /* * See what is needed for reconfiguration */ /* Timing fields */ if (c->t1 != 0 && c->t1 != gsm->t1) need_restart = 1; if (c->t2 != 0 && c->t2 != gsm->t2) need_restart = 1; if (c->encapsulation != gsm->encoding) need_restart = 1; if (c->adaption != gsm->adaption) need_restart = 1; /* Requires care */ if (c->initiator != gsm->initiator) need_close = 1; if (c->mru != gsm->mru) need_restart = 1; if (c->mtu != gsm->mtu) need_restart = 1; /* * Close down what is needed, restart and initiate the new * configuration */ if (need_close || need_restart) { int ret; ret = gsm_disconnect(gsm); if (ret) return ret; } if (need_restart) gsm_cleanup_mux(gsm); gsm->initiator = c->initiator; gsm->mru = c->mru; gsm->mtu = c->mtu; gsm->encoding = c->encapsulation; gsm->adaption = c->adaption; gsm->n2 = c->n2; if (c->i == 1) gsm->ftype = UIH; else if (c->i == 2) gsm->ftype = UI; if (c->t1) gsm->t1 = c->t1; if (c->t2) gsm->t2 = c->t2; /* FIXME: We need to separate activation/deactivation from adding and removing from the mux array */ if (need_restart) gsm_activate_mux(gsm); if (gsm->initiator && need_close) gsm_dlci_begin_open(gsm->dlci[0]); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox40594.85%125.00%
Ken Mills143.28%250.00%
Sascha Hauer81.87%125.00%
Total427100.00%4100.00%


static int gsmld_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { struct gsm_config c; struct gsm_mux *gsm = tty->disc_data; switch (cmd) { case GSMIOC_GETCONF: memset(&c, 0, sizeof(c)); c.adaption = gsm->adaption; c.encapsulation = gsm->encoding; c.initiator = gsm->initiator; c.t1 = gsm->t1; c.t2 = gsm->t2; c.t3 = 0; /* Not supported */ c.n2 = gsm->n2; if (gsm->ftype == UIH) c.i = 1; else c.i = 2; pr_debug("Ftype %d i %d\n", gsm->ftype, c.i); c.mru = gsm->mru; c.mtu = gsm->mtu; c.k = 0; if (copy_to_user((void *)arg, &c, sizeof(c))) return -EFAULT; return 0; case GSMIOC_SETCONF: if (copy_from_user(&c, (void *)arg, sizeof(c))) return -EFAULT; return gsmld_config(tty, gsm, &c); default: return n_tty_ioctl_helper(tty, file, cmd, arg); } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox246100.00%2100.00%
Total246100.00%2100.00%

#ifdef CONFIG_COMPAT
static long gsmld_compat_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { return gsmld_ioctl(tty, file, cmd, arg); }

Contributors

PersonTokensPropCommitsCommitProp
Lars Poeschel36100.00%1100.00%
Total36100.00%1100.00%

#endif /* * Network interface * */
static int gsm_mux_net_open(struct net_device *net) { pr_debug("%s called\n", __func__); netif_start_queue(net); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby2388.46%150.00%
Alan Cox311.54%150.00%
Total26100.00%2100.00%


static int gsm_mux_net_close(struct net_device *net) { netif_stop_queue(net); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby1263.16%150.00%
Alan Cox736.84%150.00%
Total19100.00%2100.00%


static void dlci_net_free(struct gsm_dlci *dlci) { if (!dlci->net) { WARN_ON(1); return; } dlci->adaption = dlci->prev_adaption; dlci->data = dlci->prev_data; free_netdev(dlci->net); dlci->net = NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby55100.00%1100.00%
Total55100.00%1100.00%


static void net_free(struct kref *ref) { struct gsm_mux_net *mux_net; struct gsm_dlci *dlci; mux_net = container_of(ref, struct gsm_mux_net, ref); dlci = mux_net->dlci; if (dlci->net) { unregister_netdev(dlci->net); dlci_net_free(dlci); } }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby59100.00%1100.00%
Total59100.00%1100.00%


static inline void muxnet_get(struct gsm_mux_net *mux_net) { kref_get(&mux_net->ref); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby20100.00%1100.00%
Total20100.00%1100.00%


static inline void muxnet_put(struct gsm_mux_net *mux_net) { kref_put(&mux_net->ref, net_free); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby22100.00%1100.00%
Total22100.00%1100.00%


static int gsm_mux_net_start_xmit(struct sk_buff *skb, struct net_device *net) { struct gsm_mux_net *mux_net = netdev_priv(net); struct gsm_dlci *dlci = mux_net->dlci; muxnet_get(mux_net); skb_queue_head(&dlci->skb_list, skb); net->stats.tx_packets++; net->stats.tx_bytes += skb->len; gsm_dlci_data_kick(dlci); /* And tell the kernel when the last transmit started. */ netif_trans_update(net); muxnet_put(mux_net); return NETDEV_TX_OK; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby7991.86%250.00%
Tobias Klauser44.65%125.00%
Florian Westphal33.49%125.00%
Total86100.00%4100.00%

/* called when a packet did not ack after watchdogtimeout */
static void gsm_mux_net_tx_timeout(struct net_device *net) { /* Tell syslog we are hosed. */ dev_dbg(&net->dev, "Tx timed out.\n"); /* Update statistics */ net->stats.tx_errors++; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby2893.33%150.00%
Tobias Klauser26.67%150.00%
Total30100.00%2100.00%


static void gsm_mux_rx_netchar(struct gsm_dlci *dlci, unsigned char *in_buf, int size) { struct net_device *net = dlci->net; struct sk_buff *skb; struct gsm_mux_net *mux_net = netdev_priv(net); muxnet_get(mux_net); /* Allocate an sk_buff */ skb = dev_alloc_skb(size + NET_IP_ALIGN); if (!skb) { /* We got no receive buffer. */ net->stats.rx_dropped++; muxnet_put(mux_net); return; } skb_reserve(skb, NET_IP_ALIGN); skb_put_data(skb, in_buf, size); skb->dev = net; skb->protocol = htons(ETH_P_IP); /* Ship it off to the kernel */ netif_rx(skb); /* update out statistics */ net->stats.rx_packets++; net->stats.rx_bytes += size; muxnet_put(mux_net); return; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby13094.20%240.00%
Tobias Klauser64.35%120.00%
Johannes Berg10.72%120.00%
Vaishali Thakkar10.72%120.00%
Total138100.00%5100.00%


static void gsm_mux_net_init(struct net_device *net) { static const struct net_device_ops gsm_netdev_ops = { .ndo_open = gsm_mux_net_open, .ndo_stop = gsm_mux_net_close, .ndo_start_xmit = gsm_mux_net_start_xmit, .ndo_tx_timeout = gsm_mux_net_tx_timeout, }; net->netdev_ops = &gsm_netdev_ops; /* fill in the other fields */ net->watchdog_timeo = GSM_NET_TX_TIMEOUT; net->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; net->type = ARPHRD_NONE; net->tx_queue_len = 10; }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby75100.00%1100.00%
Total75100.00%1100.00%

/* caller holds the dlci mutex */
static void gsm_destroy_network(struct gsm_dlci *dlci) { struct gsm_mux_net *mux_net; pr_debug("destroy network interface"); if (!dlci->net) return; mux_net = netdev_priv(dlci->net); muxnet_put(mux_net); }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby43100.00%2100.00%
Total43100.00%2100.00%

/* caller holds the dlci mutex */
static int gsm_create_network(struct gsm_dlci *dlci, struct gsm_netconfig *nc) { char *netname; int retval = 0; struct net_device *net; struct gsm_mux_net *mux_net; if (!capable(CAP_NET_ADMIN)) return -EPERM; /* Already in a non tty mode */ if (dlci->adaption > 2) return -EBUSY; if (nc->protocol != htons(ETH_P_IP)) return -EPROTONOSUPPORT; if (nc->adaption != 3 && nc->adaption != 4) return -EPROTONOSUPPORT; pr_debug("create network interface"); netname = "gsm%d"; if (nc->if_name[0] != '\0') netname = nc->if_name; net = alloc_netdev(sizeof(struct gsm_mux_net), netname, NET_NAME_UNKNOWN, gsm_mux_net_init); if (!net) { pr_err("alloc_netdev failed"); return -ENOMEM; } net->mtu = dlci->gsm->mtu; net->min_mtu = 8; net->max_mtu = dlci->gsm->mtu; mux_net = netdev_priv(net); mux_net->dlci = dlci; kref_init(&mux_net->ref); strncpy(nc->if_name, net->name, IFNAMSIZ); /* return net name */ /* reconfigure dlci for network */ dlci->prev_adaption = dlci->adaption; dlci->prev_data = dlci->data; dlci->adaption = nc->adaption; dlci->data = gsm_mux_rx_netchar; dlci->net = net; pr_debug("register netdev"); retval = register_netdev(net); if (retval) { pr_err("network register fail %d\n", retval); dlci_net_free(dlci); return retval; } return net->ifindex; /* return network index */ }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby27193.77%133.33%
Jarod Wilson165.54%133.33%
Tom Gundersen20.69%133.33%
Total289100.00%3100.00%

/* Line discipline for real tty */ static struct tty_ldisc_ops tty_ldisc_packet = { .owner = THIS_MODULE, .magic = TTY_LDISC_MAGIC, .name = "n_gsm", .open = gsmld_open, .close = gsmld_close, .flush_buffer = gsmld_flush_buffer, .read = gsmld_read, .write = gsmld_write, #ifdef CONFIG_COMPAT .compat_ioctl = gsmld_compat_ioctl, #endif .ioctl = gsmld_ioctl, .poll = gsmld_poll, .receive_buf = gsmld_receive_buf, .write_wakeup = gsmld_write_wakeup }; /* * Virtual tty side */ #define TX_SIZE 512
static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk) { u8 modembits[5]; struct gsm_control *ctrl; int len = 2; if (brk) len++; modembits[0] = len << 1 | EA; /* Data bytes */ modembits[1] = dlci->addr << 2 | 3; /* DLCI, EA, 1 */ modembits[2] = gsm_encode_modem(dlci) << 1 | EA; if (brk) modembits[3] = brk << 4 | 2 | EA; /* Valid, EA */ ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len + 1); if (ctrl == NULL) return -ENOMEM; return gsm_control_wait(dlci->gsm, ctrl); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox132100.00%1100.00%
Total132100.00%1100.00%


static int gsm_carrier_raised(struct tty_port *port) { struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); /* Not yet open so no carrier info */ if (dlci->state != DLCI_OPEN) return 0; if (debug & 2) return 1; return dlci->modem_rx & TIOCM_CD; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox54100.00%1100.00%
Total54100.00%1100.00%


static void gsm_dtr_rts(struct tty_port *port, int onoff) { struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); unsigned int modem_tx = dlci->modem_tx; if (onoff) modem_tx |= TIOCM_DTR | TIOCM_RTS; else modem_tx &= ~(TIOCM_DTR | TIOCM_RTS); if (modem_tx != dlci->modem_tx) { dlci->modem_tx = modem_tx; gsmtty_modem_update(dlci, 0); } }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox80100.00%1100.00%
Total80100.00%1100.00%

static const struct tty_port_operations gsm_port_ops = { .carrier_raised = gsm_carrier_raised, .dtr_rts = gsm_dtr_rts, .destruct = gsm_dlci_free, };
static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty) { struct gsm_mux *gsm; struct gsm_dlci *dlci; unsigned int line = tty->index; unsigned int mux = line >> 6; bool alloc = false; int ret; line = line & 0x3F; if (mux >= MAX_MUX) return -ENXIO; /* FIXME: we need to lock gsm_mux for lifetimes of ttys eventually */ if (gsm_mux[mux] == NULL) return -EUNATCH; if (line == 0 || line > 61) /* 62/63 reserved */ return -ECHRNG; gsm = gsm_mux[mux]; if (gsm->dead) return -EL2HLT; /* If DLCI 0 is not yet fully open return an error. This is ok from a locking perspective as we don't have to worry about this if DLCI0 is lost */ mutex_lock(&gsm->mutex); if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN) { mutex_unlock(&gsm->mutex); return -EL2NSYNC; } dlci = gsm->dlci[line]; if (dlci == NULL) { alloc = true; dlci = gsm_dlci_alloc(gsm, line); } if (dlci == NULL) { mutex_unlock(&gsm->mutex); return -ENOMEM; } ret = tty_port_install(&dlci->port, driver, tty); if (ret) { if (alloc) dlci_put(dlci); mutex_unlock(&gsm->mutex); return ret; } dlci_get(dlci); dlci_get(gsm->dlci[0]); mux_get(gsm); tty->driver_data = dlci; mutex_unlock(&gsm->mutex); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox14551.42%120.00%
Chao Bi6422.70%120.00%
Jiri Slaby4817.02%120.00%
xiao jin248.51%120.00%
Aldo Iljazi10.35%120.00%
Total282100.00%5100.00%


static int gsmtty_open(struct tty_struct *tty, struct file *filp) { struct gsm_dlci *dlci = tty->driver_data; struct tty_port *port = &dlci->port; port->count++; tty_port_tty_set(port, tty); dlci->modem_rx = 0; /* We could in theory open and close before we wait - eg if we get a DM straight back. This is ok as that will have caused a hangup */ tty_port_set_initialized(port, 1); /* Start sending off SABM messages */ gsm_dlci_begin_open(dlci); /* And wait for virtual carrier */ return tty_port_block_til_ready(port, tty, filp); }

Contributors

PersonTokensPropCommitsCommitProp
Jiri Slaby3950.00%133.33%
Alan Cox3646.15%133.33%
Peter Hurley33.85%133.33%
Total78100.00%3100.00%


static void gsmtty_close(struct tty_struct *tty, struct file *filp) { struct gsm_dlci *dlci = tty->driver_data; struct gsm_mux *gsm; if (dlci == NULL) return; if (dlci->state == DLCI_CLOSED) return; mutex_lock(&dlci->mutex); gsm_destroy_network(dlci); mutex_unlock(&dlci->mutex); gsm = dlci->gsm; if (tty_port_close_start(&dlci->port, tty, filp) == 0) return; gsm_dlci_begin_close(dlci); if (tty_port_initialized(&dlci->port) && C_HUPCL(tty)) tty_port_lower_dtr_rts(&dlci->port); tty_port_close_end(&dlci->port, tty); tty_port_tty_set(&dlci->port, NULL); return; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox7352.52%114.29%
Russ Gorby3223.02%228.57%
Johan Hovold2115.11%114.29%
Dirkjan Bussink96.47%114.29%
Chao Bi21.44%114.29%
Peter Hurley21.44%114.29%
Total139100.00%7100.00%


static void gsmtty_hangup(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return; tty_port_hangup(&dlci->port); gsm_dlci_begin_close(dlci); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox3378.57%150.00%
Dirkjan Bussink921.43%150.00%
Total42100.00%2100.00%


static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf, int len) { int sent; struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return -EINVAL; /* Stuff the bytes into the fifo queue */ sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock); /* Need to kick the channel */ gsm_dlci_data_kick(dlci); return sent; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox5576.39%150.00%
Dirkjan Bussink1723.61%150.00%
Total72100.00%2100.00%


static int gsmtty_write_room(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return -EINVAL; return TX_SIZE - kfifo_len(dlci->fifo); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox3071.43%150.00%
Dirkjan Bussink1228.57%150.00%
Total42100.00%2100.00%


static int gsmtty_chars_in_buffer(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return -EINVAL; return kfifo_len(dlci->fifo); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox2870.00%150.00%
Dirkjan Bussink1230.00%150.00%
Total40100.00%2100.00%


static void gsmtty_flush_buffer(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return; /* Caution needed: If we implement reliable transport classes then the data being transmitted can't simply be junked once it has first hit the stack. Until then we can just blow it away */ kfifo_reset(dlci->fifo); /* Need to unhook this DLCI from the transmit queue logic */ }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox2976.32%150.00%
Dirkjan Bussink923.68%150.00%
Total38100.00%2100.00%


static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout) { /* The FIFO handles the queue so the kernel will do the right thing waiting on chars_in_buffer before calling us. No work to do here */ }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox15100.00%1100.00%
Total15100.00%1100.00%


static int gsmtty_tiocmget(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return -EINVAL; return dlci->modem_rx; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox2567.57%150.00%
Dirkjan Bussink1232.43%150.00%
Total37100.00%2100.00%


static int gsmtty_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) { struct gsm_dlci *dlci = tty->driver_data; unsigned int modem_tx = dlci->modem_tx; if (dlci->state == DLCI_CLOSED) return -EINVAL; modem_tx &= ~clear; modem_tx |= set; if (modem_tx != dlci->modem_tx) { dlci->modem_tx = modem_tx; return gsmtty_modem_update(dlci, 0); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox7184.52%133.33%
Dirkjan Bussink1214.29%133.33%
Nikola Diklic-Perin11.19%133.33%
Total84100.00%3100.00%


static int gsmtty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { struct gsm_dlci *dlci = tty->driver_data; struct gsm_netconfig nc; int index; if (dlci->state == DLCI_CLOSED) return -EINVAL; switch (cmd) { case GSMIOC_ENABLE_NET: if (copy_from_user(&nc, (void __user *)arg, sizeof(nc))) return -EFAULT; nc.if_name[IFNAMSIZ-1] = '\0'; /* return net interface index or error code */ mutex_lock(&dlci->mutex); index = gsm_create_network(dlci, &nc); mutex_unlock(&dlci->mutex); if (copy_to_user((void __user *)arg, &nc, sizeof(nc))) return -EFAULT; return index; case GSMIOC_DISABLE_NET: if (!capable(CAP_NET_ADMIN)) return -EPERM; mutex_lock(&dlci->mutex); gsm_destroy_network(dlci); mutex_unlock(&dlci->mutex); return 0; default: return -ENOIOCTLCMD; } }

Contributors

PersonTokensPropCommitsCommitProp
Russ Gorby15481.48%133.33%
Alan Cox2312.17%133.33%
Dirkjan Bussink126.35%133.33%
Total189100.00%3100.00%


static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return; /* For the moment its fixed. In actual fact the speed information for the virtual channel can be propogated in both directions by the RPN control message. This however rapidly gets nasty as we then have to remap modem signals each way according to whether our virtual cable is null modem etc .. */ tty_termios_copy_hw(&tty->termios, old); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox2760.00%266.67%
Dirkjan Bussink1840.00%133.33%
Total45100.00%3100.00%


static void gsmtty_throttle(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return; if (C_CRTSCTS(tty)) dlci->modem_tx &= ~TIOCM_DTR; dlci->throttled = 1; /* Send an MSC with DTR cleared */ gsmtty_modem_update(dlci, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox4578.95%133.33%
Dirkjan Bussink915.79%133.33%
Peter Hurley35.26%133.33%
Total57100.00%3100.00%


static void gsmtty_unthrottle(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; if (dlci->state == DLCI_CLOSED) return; if (C_CRTSCTS(tty)) dlci->modem_tx |= TIOCM_DTR; dlci->throttled = 0; /* Send an MSC with DTR set */ gsmtty_modem_update(dlci, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox4478.57%133.33%
Dirkjan Bussink916.07%133.33%
Peter Hurley35.36%133.33%
Total56100.00%3100.00%


static int gsmtty_break_ctl(struct tty_struct *tty, int state) { struct gsm_dlci *dlci = tty->driver_data; int encode = 0; /* Off */ if (dlci->state == DLCI_CLOSED) return -EINVAL; if (state == -1) /* "On indefinitely" - we can't encode this properly */ encode = 0x0F; else if (state > 0) { encode = state / 200; /* mS to encoding */ if (encode > 0x0F) encode = 0x0F; /* Best effort */ } return gsmtty_modem_update(dlci, encode); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox7686.36%150.00%
Dirkjan Bussink1213.64%150.00%
Total88100.00%2100.00%


static void gsmtty_cleanup(struct tty_struct *tty) { struct gsm_dlci *dlci = tty->driver_data; struct gsm_mux *gsm = dlci->gsm; dlci_put(dlci); dlci_put(gsm->dlci[0]); mux_put(gsm); }

Contributors

PersonTokensPropCommitsCommitProp
Chao Bi4897.96%150.00%
Pan Xinhui12.04%150.00%
Total49100.00%2100.00%

/* Virtual ttys for the demux */ static const struct tty_operations gsmtty_ops = { .install = gsmtty_install, .open = gsmtty_open, .close = gsmtty_close, .write = gsmtty_write, .write_room = gsmtty_write_room, .chars_in_buffer = gsmtty_chars_in_buffer, .flush_buffer = gsmtty_flush_buffer, .ioctl = gsmtty_ioctl, .throttle = gsmtty_throttle, .unthrottle = gsmtty_unthrottle, .set_termios = gsmtty_set_termios, .hangup = gsmtty_hangup, .wait_until_sent = gsmtty_wait_until_sent, .tiocmget = gsmtty_tiocmget, .tiocmset = gsmtty_tiocmset, .break_ctl = gsmtty_break_ctl, .cleanup = gsmtty_cleanup, };
static int __init gsm_init(void) { /* Fill in our line protocol discipline, and register it */ int status = tty_register_ldisc(N_GSM0710, &tty_ldisc_packet); if (status != 0) { pr_err("n_gsm: can't register line discipline (err = %d)\n", status); return status; } gsm_tty_driver = alloc_tty_driver(256); if (!gsm_tty_driver) { tty_unregister_ldisc(N_GSM0710); pr_err("gsm_init: tty allocation failed.\n"); return -EINVAL; } gsm_tty_driver->driver_name = "gsmtty"; gsm_tty_driver->name = "gsmtty"; gsm_tty_driver->major = 0; /* Dynamic */ gsm_tty_driver->minor_start = 0; gsm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL; gsm_tty_driver->subtype = SERIAL_TYPE_NORMAL; gsm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_HARDWARE_BREAK; gsm_tty_driver->init_termios = tty_std_termios; /* Fixme */ gsm_tty_driver->init_termios.c_lflag &= ~ECHO; tty_set_operations(gsm_tty_driver, &gsmtty_ops); spin_lock_init(&gsm_mux_lock); if (tty_register_driver(gsm_tty_driver)) { put_tty_driver(gsm_tty_driver); tty_unregister_ldisc(N_GSM0710); pr_err("gsm_init: tty registration failed.\n"); return -EBUSY; } pr_debug("gsm_init: loaded as %d,%d.\n", gsm_tty_driver->major, gsm_tty_driver->minor_start); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox188100.00%2100.00%
Total188100.00%2100.00%


static void __exit gsm_exit(void) { int status = tty_unregister_ldisc(N_GSM0710); if (status != 0) pr_err("n_gsm: can't unregister line discipline (err = %d)\n", status); tty_unregister_driver(gsm_tty_driver); put_tty_driver(gsm_tty_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Alan Cox40100.00%2100.00%
Total40100.00%2100.00%

module_init(gsm_init); module_exit(gsm_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_LDISC(N_GSM0710);

Overall Contributors

PersonTokensPropCommitsCommitProp
Alan Cox1015879.37%710.77%
Russ Gorby160012.50%1015.38%
Dirkjan Bussink1991.55%11.54%
Jiri Slaby1521.19%812.31%
Chao Bi1451.13%11.54%
Sascha Hauer1100.86%11.54%
Lars Poeschel1060.83%23.08%
Frederic Berat800.63%11.54%
Pan Xinhui390.30%34.62%
Mikhail Kshevetskiy310.24%34.62%
Ken Mills300.23%57.69%
xiao jin240.19%11.54%
Johan Hovold210.16%11.54%
Peter Hurley200.16%34.62%
Dan Carpenter160.13%11.54%
Jarod Wilson160.13%11.54%
Joe Perches130.10%11.54%
Tobias Klauser130.10%11.54%
Rashika Kheria40.03%11.54%
Lucas De Marchi40.03%11.54%
Aldo Iljazi30.02%11.54%
Florian Westphal30.02%11.54%
Tom Gundersen20.02%11.54%
Vaishali Thakkar10.01%11.54%
Julia Lawall10.01%11.54%
Johannes Berg10.01%11.54%
Ingo Molnar10.01%11.54%
Nikola Diklic-Perin10.01%11.54%
Justin P. Mattock10.01%11.54%
Linus Torvalds10.01%11.54%
Geert Uytterhoeven10.01%11.54%
Lad Prabhakar10.01%11.54%
Total12798100.00%65100.00%
Directory: drivers/tty
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.