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Release 4.11 drivers/input/joystick/grip_mp.c

/*
 *  Driver for the Gravis Grip Multiport, a gamepad "hub" that
 *  connects up to four 9-pin digital gamepads/joysticks.
 *  Driver tested on SMP and UP kernel versions 2.4.18-4 and 2.4.18-5.
 *
 *  Thanks to Chris Gassib for helpful advice.
 *
 *  Copyright (c)      2002 Brian Bonnlander, Bill Soudan
 *  Copyright (c) 1998-2000 Vojtech Pavlik
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/gameport.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/jiffies.h>


#define DRIVER_DESC	"Gravis Grip Multiport driver"

MODULE_AUTHOR("Brian Bonnlander");

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

#ifdef GRIP_DEBUG

#define dbg(format, arg...) printk(KERN_ERR __FILE__ ": " format "\n" , ## arg)
#else

#define dbg(format, arg...) do {} while (0)
#endif


#define GRIP_MAX_PORTS	4
/*
 * Grip multiport state
 */


struct grip_port {
	
struct input_dev *dev;
	
int mode;
	
int registered;

	/* individual gamepad states */
	
int buttons;
	
int xaxes;
	
int yaxes;
	
int dirty;     /* has the state been updated? */
};


struct grip_mp {
	
struct gameport *gameport;
	
struct grip_port *port[GRIP_MAX_PORTS];
	
int reads;
	
int bads;
};

/*
 * Multiport packet interpretation
 */


#define PACKET_FULL          0x80000000       
/* packet is full                        */

#define PACKET_IO_FAST       0x40000000       
/* 3 bits per gameport read              */

#define PACKET_IO_SLOW       0x20000000       
/* 1 bit per gameport read               */

#define PACKET_MP_MORE       0x04000000       
/* multiport wants to send more          */

#define PACKET_MP_DONE       0x02000000       
/* multiport done sending                */

/*
 * Packet status code interpretation
 */


#define IO_GOT_PACKET        0x0100           
/* Got a packet                           */

#define IO_MODE_FAST         0x0200           
/* Used 3 data bits per gameport read     */

#define IO_SLOT_CHANGE       0x0800           
/* Multiport physical slot status changed */

#define IO_DONE              0x1000           
/* Multiport is done sending packets      */

#define IO_RETRY             0x4000           
/* Try again later to get packet          */

#define IO_RESET             0x8000           
/* Force multiport to resend all packets  */

/*
 * Gamepad configuration data.  Other 9-pin digital joystick devices
 * may work with the multiport, so this may not be an exhaustive list!
 * Commodore 64 joystick remains untested.
 */


#define GRIP_INIT_DELAY         2000          
/*  2 ms */


#define GRIP_MODE_NONE		0

#define GRIP_MODE_RESET         1

#define GRIP_MODE_GP		2

#define GRIP_MODE_C64		3


static const int grip_btn_gp[]  = { BTN_TR, BTN_TL, BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, -1 };

static const int grip_btn_c64[] = { BTN_JOYSTICK, -1 };


static const int grip_abs_gp[]  = { ABS_X, ABS_Y, -1 };

static const int grip_abs_c64[] = { ABS_X, ABS_Y, -1 };


static const int *grip_abs[] = { NULL, NULL, grip_abs_gp, grip_abs_c64 };

static const int *grip_btn[] = { NULL, NULL, grip_btn_gp, grip_btn_c64 };


static const char *grip_name[] = { NULL, NULL, "Gravis Grip Pad", "Commodore 64 Joystick" };


static const int init_seq[] = {
	1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
	1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1,
	1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
	0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1 };

/* Maps multiport directional values to X,Y axis values (each axis encoded in 3 bits) */


static const int axis_map[] = { 5, 9, 1, 5, 6, 10, 2, 6, 4, 8, 0, 4, 5, 9, 1, 5 };

static int register_slot(int i, struct grip_mp *grip);

/*
 * Returns whether an odd or even number of bits are on in pkt.
 */


static int bit_parity(u32 pkt) { int x = pkt ^ (pkt >> 16); x ^= x >> 8; x ^= x >> 4; x ^= x >> 2; x ^= x >> 1; return x & 1; }

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Vojtech Pavlik49100.00%1100.00%
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/* * Poll gameport; return true if all bits set in 'onbits' are on and * all bits set in 'offbits' are off. */
static inline int poll_until(u8 onbits, u8 offbits, int u_sec, struct gameport* gp, u8 *data) { int i, nloops; nloops = gameport_time(gp, u_sec); for (i = 0; i < nloops; i++) { *data = gameport_read(gp); if ((*data & onbits) == onbits && (~(*data) & offbits) == offbits) return 1; } dbg("gameport timed out after %d microseconds.\n", u_sec); return 0; }

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/* * Gets a 28-bit packet from the multiport. * * After getting a packet successfully, commands encoded by sendcode may * be sent to the multiport. * * The multiport clock value is reflected in gameport bit B4. * * Returns a packet status code indicating whether packet is valid, the transfer * mode, and any error conditions. * * sendflags: current I/O status * sendcode: data to send to the multiport if sendflags is nonzero */
static int mp_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet) { u8 raw_data; /* raw data from gameport */ u8 data_mask; /* packet data bits from raw_data */ u32 pkt; /* packet temporary storage */ int bits_per_read; /* num packet bits per gameport read */ int portvals = 0; /* used for port value sanity check */ int i; /* Gameport bits B0, B4, B5 should first be off, then B4 should come on. */ *packet = 0; raw_data = gameport_read(gameport); if (raw_data & 1) return IO_RETRY; for (i = 0; i < 64; i++) { raw_data = gameport_read(gameport); portvals |= 1 << ((raw_data >> 4) & 3); /* Demux B4, B5 */ } if (portvals == 1) { /* B4, B5 off */ raw_data = gameport_read(gameport); portvals = raw_data & 0xf0; if (raw_data & 0x31) return IO_RESET; gameport_trigger(gameport); if (!poll_until(0x10, 0, 308, gameport, &raw_data)) return IO_RESET; } else return IO_RETRY; /* Determine packet transfer mode and prepare for packet construction. */ if (raw_data & 0x20) { /* 3 data bits/read */ portvals |= raw_data >> 4; /* Compare B4-B7 before & after trigger */ if (portvals != 0xb) return 0; data_mask = 7; bits_per_read = 3; pkt = (PACKET_FULL | PACKET_IO_FAST) >> 28; } else { /* 1 data bit/read */ data_mask = 1; bits_per_read = 1; pkt = (PACKET_FULL | PACKET_IO_SLOW) >> 28; } /* Construct a packet. Final data bits must be zero. */ while (1) { if (!poll_until(0, 0x10, 77, gameport, &raw_data)) return IO_RESET; raw_data = (raw_data >> 5) & data_mask; if (pkt & PACKET_FULL) break; pkt = (pkt << bits_per_read) | raw_data; if (!poll_until(0x10, 0, 77, gameport, &raw_data)) return IO_RESET; } if (raw_data) return IO_RESET; /* If 3 bits/read used, drop from 30 bits to 28. */ if (bits_per_read == 3) { pkt = (pkt & 0xffff0000) | ((pkt << 1) & 0xffff); pkt = (pkt >> 2) | 0xf0000000; } if (bit_parity(pkt) == 1) return IO_RESET; /* Acknowledge packet receipt */ if (!poll_until(0x30, 0, 77, gameport, &raw_data)) return IO_RESET; raw_data = gameport_read(gameport); if (raw_data & 1) return IO_RESET; gameport_trigger(gameport); if (!poll_until(0, 0x20, 77, gameport, &raw_data)) return IO_RESET; /* Return if we just wanted the packet or multiport wants to send more */ *packet = pkt; if ((sendflags == 0) || ((sendflags & IO_RETRY) && !(pkt & PACKET_MP_DONE))) return IO_GOT_PACKET; if (pkt & PACKET_MP_MORE) return IO_GOT_PACKET | IO_RETRY; /* Multiport is done sending packets and is ready to receive data */ if (!poll_until(0x20, 0, 77, gameport, &raw_data)) return IO_GOT_PACKET | IO_RESET; raw_data = gameport_read(gameport); if (raw_data & 1) return IO_GOT_PACKET | IO_RESET; /* Trigger gameport based on bits in sendcode */ gameport_trigger(gameport); do { if (!poll_until(0x20, 0x10, 116, gameport, &raw_data)) return IO_GOT_PACKET | IO_RESET; if (!poll_until(0x30, 0, 193, gameport, &raw_data)) return IO_GOT_PACKET | IO_RESET; if (raw_data & 1) return IO_GOT_PACKET | IO_RESET; if (sendcode & 1) gameport_trigger(gameport); sendcode >>= 1; } while (sendcode); return IO_GOT_PACKET | IO_MODE_FAST; }

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/* * Disables and restores interrupts for mp_io(), which does the actual I/O. */
static int multiport_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet) { int status; unsigned long flags; local_irq_save(flags); status = mp_io(gameport, sendflags, sendcode, packet); local_irq_restore(flags); return status; }

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/* * Puts multiport into digital mode. Multiport LED turns green. * * Returns true if a valid digital packet was received, false otherwise. */
static int dig_mode_start(struct gameport *gameport, u32 *packet) { int i; int flags, tries = 0, bads = 0; for (i = 0; i < ARRAY_SIZE(init_seq); i++) { /* Send magic sequence */ if (init_seq[i]) gameport_trigger(gameport); udelay(GRIP_INIT_DELAY); } for (i = 0; i < 16; i++) /* Wait for multiport to settle */ udelay(GRIP_INIT_DELAY); while (tries < 64 && bads < 8) { /* Reset multiport and try getting a packet */ flags = multiport_io(gameport, IO_RESET, 0x27, packet); if (flags & IO_MODE_FAST) return 1; if (flags & IO_RETRY) tries++; else bads++; } return 0; }

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Vojtech Pavlik13197.04%150.00%
Andi Drebes42.96%150.00%
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/* * Packet structure: B0-B15 => gamepad state * B16-B20 => gamepad device type * B21-B24 => multiport slot index (1-4) * * Known device types: 0x1f (grip pad), 0x0 (no device). Others may exist. * * Returns the packet status. */
static int get_and_decode_packet(struct grip_mp *grip, int flags) { struct grip_port *port; u32 packet; int joytype = 0; int slot; /* Get a packet and check for validity */ flags &= IO_RESET | IO_RETRY; flags = multiport_io(grip->gameport, flags, 0, &packet); grip->reads++; if (packet & PACKET_MP_DONE) flags |= IO_DONE; if (flags && !(flags & IO_GOT_PACKET)) { grip->bads++; return flags; } /* Ignore non-gamepad packets, e.g. multiport hardware version */ slot = ((packet >> 21) & 0xf) - 1; if ((slot < 0) || (slot > 3)) return flags; port = grip->port[slot]; /* * Handle "reset" packets, which occur at startup, and when gamepads * are removed or plugged in. May contain configuration of a new gamepad. */ joytype = (packet >> 16) & 0x1f; if (!joytype) { if (port->registered) { printk(KERN_INFO "grip_mp: removing %s, slot %d\n", grip_name[port->mode], slot); input_unregister_device(port->dev); port->registered = 0; } dbg("Reset: grip multiport slot %d\n", slot); port->mode = GRIP_MODE_RESET; flags |= IO_SLOT_CHANGE; return flags; } /* Interpret a grip pad packet */ if (joytype == 0x1f) { int dir = (packet >> 8) & 0xf; /* eight way directional value */ port->buttons = (~packet) & 0xff; port->yaxes = ((axis_map[dir] >> 2) & 3) - 1; port->xaxes = (axis_map[dir] & 3) - 1; port->dirty = 1; if (port->mode == GRIP_MODE_RESET) flags |= IO_SLOT_CHANGE; port->mode = GRIP_MODE_GP; if (!port->registered) { dbg("New Grip pad in multiport slot %d.\n", slot); if (register_slot(slot, grip)) { port->mode = GRIP_MODE_RESET; port->dirty = 0; } } return flags; } /* Handle non-grip device codes. For now, just print diagnostics. */ { static int strange_code = 0; if (strange_code != joytype) { printk(KERN_INFO "Possible non-grip pad/joystick detected.\n"); printk(KERN_INFO "Got joy type 0x%x and packet 0x%x.\n", joytype, packet); strange_code = joytype; } } return flags; }

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Vojtech Pavlik33488.83%133.33%
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/* * Returns true if all multiport slot states appear valid. */
static int slots_valid(struct grip_mp *grip) { int flags, slot, invalid = 0, active = 0; flags = get_and_decode_packet(grip, 0); if (!(flags & IO_GOT_PACKET)) return 0; for (slot = 0; slot < 4; slot++) { if (grip->port[slot]->mode == GRIP_MODE_RESET) invalid = 1; if (grip->port[slot]->mode != GRIP_MODE_NONE) active = 1; } /* Return true if no active slot but multiport sent all its data */ if (!active) return (flags & IO_DONE) ? 1 : 0; /* Return false if invalid device code received */ return invalid ? 0 : 1; }

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Vojtech Pavlik11394.96%150.00%
Dmitry Torokhov65.04%150.00%
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/* * Returns whether the multiport was placed into digital mode and * able to communicate its state successfully. */
static int multiport_init(struct grip_mp *grip) { int dig_mode, initialized = 0, tries = 0; u32 packet; dig_mode = dig_mode_start(grip->gameport, &packet); while (!dig_mode && tries < 4) { dig_mode = dig_mode_start(grip->gameport, &packet); tries++; } if (dig_mode) dbg("multiport_init(): digital mode activated.\n"); else { dbg("multiport_init(): unable to activate digital mode.\n"); return 0; } /* Get packets, store multiport state, and check state's validity */ for (tries = 0; tries < 4096; tries++) { if (slots_valid(grip)) { initialized = 1; break; } } dbg("multiport_init(): initialized == %d\n", initialized); return initialized; }

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Vojtech Pavlik12198.37%150.00%
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/* * Reports joystick state to the linux input layer. */
static void report_slot(struct grip_mp *grip, int slot) { struct grip_port *port = grip->port[slot]; int i; /* Store button states with linux input driver */ for (i = 0; i < 8; i++) input_report_key(port->dev, grip_btn_gp[i], (port->buttons >> i) & 1); /* Store axis states with linux driver */ input_report_abs(port->dev, ABS_X, port->xaxes); input_report_abs(port->dev, ABS_Y, port->yaxes); /* Tell the receiver of the events to process them */ input_sync(port->dev); port->dirty = 0; }

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Vojtech Pavlik9084.91%266.67%
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/* * Get the multiport state. */
static void grip_poll(struct gameport *gameport) { struct grip_mp *grip = gameport_get_drvdata(gameport); int i, npkts, flags; for (npkts = 0; npkts < 4; npkts++) { flags = IO_RETRY; for (i = 0; i < 32; i++) { flags = get_and_decode_packet(grip, flags); if ((flags & IO_GOT_PACKET) || !(flags & IO_RETRY)) break; } if (flags & IO_DONE) break; } for (i = 0; i < 4; i++) if (grip->port[i]->dirty) report_slot(grip, i); }

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Vojtech Pavlik10987.20%133.33%
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/* * Called when a joystick device file is opened */
static int grip_open(struct input_dev *dev) { struct grip_mp *grip = input_get_drvdata(dev); gameport_start_polling(grip->gameport); return 0; }

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Vojtech Pavlik2683.87%133.33%
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/* * Called when a joystick device file is closed */
static void grip_close(struct input_dev *dev) { struct grip_mp *grip = input_get_drvdata(dev); gameport_stop_polling(grip->gameport); }

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Vojtech Pavlik2382.14%133.33%
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/* * Tell the linux input layer about a newly plugged-in gamepad. */
static int register_slot(int slot, struct grip_mp *grip) { struct grip_port *port = grip->port[slot]; struct input_dev *input_dev; int j, t; int err; port->dev = input_dev = input_allocate_device(); if (!input_dev) return -ENOMEM; input_dev->name = grip_name[port->mode]; input_dev->id.bustype = BUS_GAMEPORT; input_dev->id.vendor = GAMEPORT_ID_VENDOR_GRAVIS; input_dev->id.product = 0x0100 + port->mode; input_dev->id.version = 0x0100; input_dev->dev.parent = &grip->gameport->dev; input_set_drvdata(input_dev, grip); input_dev->open = grip_open; input_dev->close = grip_close; input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); for (j = 0; (t = grip_abs[port->mode][j]) >= 0; j++) input_set_abs_params(input_dev, t, -1, 1, 0, 0); for (j = 0; (t = grip_btn[port->mode][j]) >= 0; j++) if (t > 0) set_bit(t, input_dev->keybit); err = input_register_device(port->dev); if (err) { input_free_device(port->dev); return err; } port->registered = 1; if (port->dirty) /* report initial state, if any */ report_slot(grip, slot); return 0; }

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static int grip_connect(struct gameport *gameport, struct gameport_driver *drv) { struct grip_mp *grip; int err; if (!(grip = kzalloc(sizeof(struct grip_mp), GFP_KERNEL))) return -ENOMEM; grip->gameport = gameport; gameport_set_drvdata(gameport, grip);