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Release 4.14 drivers/ipack/devices/ipoctal.c

/**
 * ipoctal.c
 *
 * driver for the GE IP-OCTAL boards
 *
 * Copyright (C) 2009-2012 CERN (www.cern.ch)
 * Author: Nicolas Serafini, EIC2 SA
 * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; version 2 of the License.
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/ipack.h>
#include "ipoctal.h"
#include "scc2698.h"


#define IP_OCTAL_ID_SPACE_VECTOR    0x41

#define IP_OCTAL_NB_BLOCKS          4


static const struct tty_operations ipoctal_fops;


struct ipoctal_channel {
	
struct ipoctal_stats		stats;
	
unsigned int			nb_bytes;
	
wait_queue_head_t		queue;
	
spinlock_t			lock;
	
unsigned int			pointer_read;
	
unsigned int			pointer_write;
	
struct tty_port			tty_port;
	
union scc2698_channel __iomem	*regs;
	
union scc2698_block __iomem	*block_regs;
	
unsigned int			board_id;
	
u8				isr_rx_rdy_mask;
	
u8				isr_tx_rdy_mask;
	
unsigned int			rx_enable;
};


struct ipoctal {
	
struct ipack_device		*dev;
	
unsigned int			board_id;
	
struct ipoctal_channel		channel[NR_CHANNELS];
	
struct tty_driver		*tty_drv;
	
u8 __iomem			*mem8_space;
	
u8 __iomem			*int_space;
};


static inline struct ipoctal *chan_to_ipoctal(struct ipoctal_channel *chan, unsigned int index) { return container_of(chan, struct ipoctal, channel[index]); }

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static void ipoctal_reset_channel(struct ipoctal_channel *channel) { iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr); channel->rx_enable = 0; iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr); iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr); iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr); iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr); }

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static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty) { struct ipoctal_channel *channel; channel = dev_get_drvdata(tty->dev); /* * Enable RX. TX will be enabled when * there is something to send */ iowrite8(CR_ENABLE_RX, &channel->regs->w.cr); channel->rx_enable = 1; return 0; }

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static int ipoctal_open(struct tty_struct *tty, struct file *file) { struct ipoctal_channel *channel = dev_get_drvdata(tty->dev); struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); int err; tty->driver_data = channel; if (!ipack_get_carrier(ipoctal->dev)) return -EBUSY; err = tty_port_open(&channel->tty_port, tty, file); if (err) ipack_put_carrier(ipoctal->dev); return err; }

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Jens Taprogge66.45%337.50%
Total93100.00%8100.00%


static void ipoctal_reset_stats(struct ipoctal_stats *stats) { stats->tx = 0; stats->rx = 0; stats->rcv_break = 0; stats->framing_err = 0; stats->overrun_err = 0; stats->parity_err = 0; }

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static void ipoctal_free_channel(struct ipoctal_channel *channel) { ipoctal_reset_stats(&channel->stats); channel->pointer_read = 0; channel->pointer_write = 0; channel->nb_bytes = 0; }

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static void ipoctal_close(struct tty_struct *tty, struct file *filp) { struct ipoctal_channel *channel = tty->driver_data; tty_port_close(&channel->tty_port, tty, filp); ipoctal_free_channel(channel); }

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static int ipoctal_get_icount(struct tty_struct *tty, struct serial_icounter_struct *icount) { struct ipoctal_channel *channel = tty->driver_data; icount->cts = 0; icount->dsr = 0; icount->rng = 0; icount->dcd = 0; icount->rx = channel->stats.rx; icount->tx = channel->stats.tx; icount->frame = channel->stats.framing_err; icount->parity = channel->stats.parity_err; icount->brk = channel->stats.rcv_break; return 0; }

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static void ipoctal_irq_rx(struct ipoctal_channel *channel, u8 sr) { struct tty_port *port = &channel->tty_port; unsigned char value; unsigned char flag; u8 isr; do { value = ioread8(&channel->regs->r.rhr); flag = TTY_NORMAL; /* Error: count statistics */ if (sr & SR_ERROR) { iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr); if (sr & SR_OVERRUN_ERROR) { channel->stats.overrun_err++; /* Overrun doesn't affect the current character*/ tty_insert_flip_char(port, 0, TTY_OVERRUN); } if (sr & SR_PARITY_ERROR) { channel->stats.parity_err++; flag = TTY_PARITY; } if (sr & SR_FRAMING_ERROR) { channel->stats.framing_err++; flag = TTY_FRAME; } if (sr & SR_RECEIVED_BREAK) { channel->stats.rcv_break++; flag = TTY_BREAK; } } tty_insert_flip_char(port, value, flag); /* Check if there are more characters in RX FIFO * If there are more, the isr register for this channel * has enabled the RxRDY|FFULL bit. */ isr = ioread8(&channel->block_regs->r.isr); sr = ioread8(&channel->regs->r.sr); } while (isr & channel->isr_rx_rdy_mask); tty_flip_buffer_push(port); }

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static void ipoctal_irq_tx(struct ipoctal_channel *channel) { unsigned char value; unsigned int *pointer_write = &channel->pointer_write; if (channel->nb_bytes == 0) return; spin_lock(&channel->lock); value = channel->tty_port.xmit_buf[*pointer_write]; iowrite8(value, &channel->regs->w.thr); channel->stats.tx++; (*pointer_write)++; *pointer_write = *pointer_write % PAGE_SIZE; channel->nb_bytes--; spin_unlock(&channel->lock); }

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Samuel Iglesias Gonsálvez6058.82%225.00%
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Alberto Garcia10.98%112.50%
Total102100.00%8100.00%


static void ipoctal_irq_channel(struct ipoctal_channel *channel) { u8 isr, sr; /* The HW is organized in pair of channels. See which register we need * to read from */ isr = ioread8(&channel->block_regs->r.isr); sr = ioread8(&channel->regs->r.sr); if (isr & (IMR_DELTA_BREAK_A | IMR_DELTA_BREAK_B)) iowrite8(CR_CMD_RESET_BREAK_CHANGE, &channel->regs->w.cr); if ((sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) { iowrite8(CR_DISABLE_TX, &channel->regs->w.cr); /* In case of RS-485, change from TX to RX when finishing TX. * Half-duplex. */ if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) { iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr); iowrite8(CR_ENABLE_RX, &channel->regs->w.cr); channel->rx_enable = 1; } } /* RX data */ if ((isr & channel->isr_rx_rdy_mask) && (sr & SR_RX_READY)) ipoctal_irq_rx(channel, sr); /* TX of each character */ if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY)) ipoctal_irq_tx(channel); }

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Samuel Iglesias Gonsálvez105.21%360.00%
Total192100.00%5100.00%


static irqreturn_t ipoctal_irq_handler(void *arg) { unsigned int i; struct ipoctal *ipoctal = (struct ipoctal *) arg; /* Clear the IPack device interrupt */ readw(ipoctal->int_space + ACK_INT_REQ0); readw(ipoctal->int_space + ACK_INT_REQ1); /* Check all channels */ for (i = 0; i < NR_CHANNELS; i++) ipoctal_irq_channel(&ipoctal->channel[i]); return IRQ_HANDLED; }

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static const struct tty_port_operations ipoctal_tty_port_ops = { .dtr_rts = NULL, .activate = ipoctal_port_activate, };
static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr, unsigned int slot) { int res; int i; struct tty_driver *tty; char name[20]; struct ipoctal_channel *channel; struct ipack_region *region; void __iomem *addr; union scc2698_channel __iomem *chan_regs; union scc2698_block __iomem *block_regs; ipoctal->board_id = ipoctal->dev->id_device; region = &ipoctal->dev->region[IPACK_IO_SPACE]; addr = devm_ioremap_nocache(&ipoctal->dev->dev, region->start, region->size); if (!addr) { dev_err(&ipoctal->dev->dev, "Unable to map slot [%d:%d] IO space!\n", bus_nr, slot); return -EADDRNOTAVAIL; } /* Save the virtual address to access the registers easily */ chan_regs = (union scc2698_channel __iomem *) addr; block_regs = (union scc2698_block __iomem *) addr; region = &ipoctal->dev->region[IPACK_INT_SPACE]; ipoctal->int_space = devm_ioremap_nocache(&ipoctal->dev->dev, region->start, region->size); if (!ipoctal->int_space) { dev_err(&ipoctal->dev->dev, "Unable to map slot [%d:%d] INT space!\n", bus_nr, slot); return -EADDRNOTAVAIL; } region = &ipoctal->dev->region[IPACK_MEM8_SPACE]; ipoctal->mem8_space = devm_ioremap_nocache(&ipoctal->dev->dev, region->start, 0x8000); if (!ipoctal->mem8_space) { dev_err(&ipoctal->dev->dev, "Unable to map slot [%d:%d] MEM8 space!\n", bus_nr, slot); return -EADDRNOTAVAIL; } /* Disable RX and TX before touching anything */ for (i = 0; i < NR_CHANNELS ; i++) { struct ipoctal_channel *channel = &ipoctal->channel[i]; channel->regs = chan_regs + i; channel->block_regs = block_regs + (i >> 1); channel->board_id = ipoctal->board_id; if (i & 1) { channel->isr_tx_rdy_mask = ISR_TxRDY_B; channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_B; } else { channel->isr_tx_rdy_mask = ISR_TxRDY_A; channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_A; } ipoctal_reset_channel(channel); iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY, &channel->regs->w.mr); /* mr1 */ iowrite8(0, &channel->regs->w.mr); /* mr2 */ iowrite8(TX_CLK_9600 | RX_CLK_9600, &channel->regs->w.csr); } for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) { iowrite8(ACR_BRG_SET2, &block_regs[i].w.acr); iowrite8(OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN | OPCR_MPOb_RTSN, &block_regs[i].w.opcr); iowrite8(IMR_TxRDY_A | IMR_RxRDY_FFULL_A | IMR_DELTA_BREAK_A | IMR_TxRDY_B | IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B, &block_regs[i].w.imr); } /* Dummy write */ iowrite8(1, ipoctal->mem8_space + 1); /* Register the TTY device */ /* Each IP-OCTAL channel is a TTY port */ tty = alloc_tty_driver(NR_CHANNELS); if (!tty) return -ENOMEM; /* Fill struct tty_driver with ipoctal data */ tty->owner = THIS_MODULE; tty->driver_name = KBUILD_MODNAME; sprintf(name, KBUILD_MODNAME ".%d.%d.", bus_nr, slot); tty->name = name; tty->major = 0; tty->minor_start = 0; tty->type = TTY_DRIVER_TYPE_SERIAL; tty->subtype = SERIAL_TYPE_NORMAL; tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; tty->init_termios = tty_std_termios; tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; tty->init_termios.c_ispeed = 9600; tty->init_termios.c_ospeed = 9600; tty_set_operations(tty, &ipoctal_fops); res = tty_register_driver(tty); if (res) { dev_err(&ipoctal->dev->dev, "Can't register tty driver.\n"); put_tty_driver(tty); return res; } /* Save struct tty_driver for use it when uninstalling the device */ ipoctal->tty_drv = tty; for (i = 0; i < NR_CHANNELS; i++) { struct device *tty_dev; channel = &ipoctal->channel[i]; tty_port_init(&channel->tty_port); tty_port_alloc_xmit_buf(&channel->tty_port); channel->tty_port.ops = &ipoctal_tty_port_ops; ipoctal_reset_stats(&channel->stats); channel->nb_bytes = 0; spin_lock_init(&channel->lock); channel->pointer_read = 0; channel->pointer_write = 0; tty_dev = tty_port_register_device(&channel->tty_port, tty, i, NULL); if (IS_ERR(tty_dev)) { dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n"); tty_port_destroy(&channel->tty_port); continue; } dev_set_drvdata(tty_dev, channel); } /* * IP-OCTAL has different addresses to copy its IRQ vector. * Depending of the carrier these addresses are accesible or not. * More info in the datasheet. */ ipoctal->dev->bus->ops->request_irq(ipoctal->dev, ipoctal_irq_handler, ipoctal); return 0; }

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Federico Vaga212.49%28.70%
Jiri Slaby131.54%28.70%
Julia Lawall30.36%14.35%
Linus Torvalds10.12%14.35%
Total842100.00%23100.00%


static inline int ipoctal_copy_write_buffer(struct ipoctal_channel *channel, const unsigned char *buf, int count) { unsigned long flags; int i; unsigned int *pointer_read = &channel->pointer_read; /* Copy the bytes from the user buffer to the internal one */ for (i = 0; i < count; i++) { if (i <= (PAGE_SIZE - channel->nb_bytes)) { spin_lock_irqsave(&channel->lock, flags); channel->tty_port.xmit_buf[*pointer_read] = buf[i]; *pointer_read = (*pointer_read + 1) % PAGE_SIZE; channel->nb_bytes++; spin_unlock_irqrestore(&channel->lock, flags); } else { break; } } return i; }

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Samuel Iglesias Gonsálvez12094.49%150.00%
Jens Taprogge75.51%150.00%
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static int ipoctal_write_tty(struct tty_struct *tty, const unsigned char *buf, int count) { struct ipoctal_channel *channel = tty->driver_data; unsigned int char_copied; char_copied = ipoctal_copy_write_buffer(channel, buf, count); /* As the IP-OCTAL 485 only supports half duplex, do it manually */ if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) { iowrite8(CR_DISABLE_RX, &channel->regs->w.cr); channel->rx_enable = 0; iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr); } /* * Send a packet and then disable TX to avoid failure after several send * operations */ iowrite8(CR_ENABLE_TX, &channel->regs->w.cr); return char_copied; }

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static int ipoctal_write_room(struct tty_struct *tty) { struct ipoctal_channel *channel = tty->driver_data; return PAGE_SIZE - channel->nb_bytes; }

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static int ipoctal_chars_in_buffer(struct tty_struct *tty) { struct ipoctal_channel *channel = tty->driver_data; return channel->nb_bytes; }

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static void ipoctal_set_termios(struct tty_struct *tty, struct ktermios *old_termios) { unsigned int cflag; unsigned char mr1 = 0; unsigned char mr2 = 0; unsigned char csr = 0; struct ipoctal_channel *channel = tty->driver_data; speed_t baud; cflag = tty->termios.c_cflag; /* Disable and reset everything before change the setup */ ipoctal_reset_channel(channel); /* Set Bits per chars */ switch (cflag & CSIZE) { case CS6: mr1 |= MR1_CHRL_6_BITS; break; case CS7: mr1 |= MR1_CHRL_7_BITS; break; case CS8: default: mr1 |= MR1_CHRL_8_BITS; /* By default, select CS8 */ tty->termios.c_cflag = (cflag & ~CSIZE) | CS8; break; } /* Set Parity */ if (cflag & PARENB) if (cflag & PARODD) mr1 |= MR1_PARITY_ON | MR1_PARITY_ODD; else mr1 |= MR1_PARITY_ON | MR1_PARITY_EVEN; else mr1 |= MR1_PARITY_OFF; /* Mark or space parity is not supported */ tty->termios.c_cflag &= ~CMSPAR; /* Set stop bits */ if (cflag & CSTOPB) mr2 |= MR2_STOP_BITS_LENGTH_2; else mr2 |= MR2_STOP_BITS_LENGTH_1; /* Set the flow control */ switch (channel->board_id) { case IPACK1_DEVICE_ID_SBS_OCTAL_232: if (cflag & CRTSCTS) { mr1 |= MR1_RxRTS_CONTROL_ON; mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_ON; } else { mr1 |= MR1_RxRTS_CONTROL_OFF; mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF; } break; case IPACK1_DEVICE_ID_SBS_OCTAL_422: mr1 |= MR1_RxRTS_CONTROL_OFF; mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF; break; case IPACK1_DEVICE_ID_SBS_OCTAL_485: mr1 |= MR1_RxRTS_CONTROL_OFF; mr2 |= MR2_TxRTS_CONTROL_ON | MR2_CTS_ENABLE_TX_OFF; break; default: return; break; } baud = tty_get_baud_rate(tty); tty_termios_encode_baud_rate(&tty->termios, baud, baud); /* Set baud rate */ switch (baud) { case 75: csr |= TX_CLK_75 | RX_CLK_75; break; case 110: csr |= TX_CLK_110 | RX_CLK_110; break; case 150: csr |= TX_CLK_150 | RX_CLK_150; break; case 300: csr |= TX_CLK_300 | RX_CLK_300; break; case 600: csr |= TX_CLK_600 | RX_CLK_600; break; case 1200: csr |= TX_CLK_1200 | RX_CLK_1200; break; case 1800: csr |= TX_CLK_1800 | RX_CLK_1800; break; case 2000: csr |= TX_CLK_2000 | RX_CLK_2000; break; case 2400: csr |= TX_CLK_2400 | RX_CLK_2400; break; case 4800: csr |= TX_CLK_4800 | RX_CLK_4800; break; case 9600: csr |= TX_CLK_9600 | RX_CLK_9600; break; case 19200: csr |= TX_CLK_19200 | RX_CLK_19200; break; case 38400: default: csr |= TX_CLK_38400 | RX_CLK_38400; /* In case of default, we establish 38400 bps */ tty_termios_encode_baud_rate(&tty->termios, 38400, 38400); break; } mr1 |= MR1_ERROR_CHAR; mr1 |= MR1_RxINT_RxRDY; /* Write the control registers */ iowrite8(mr1, &channel->regs->w.mr); iowrite8(mr2, &channel->regs->w.mr); iowrite8(csr, &channel->regs->w.csr); /* Enable again the RX, if it was before */ if (channel->rx_enable) iowrite8(CR_ENABLE_RX, &