* [PATCH RESEND] max3100 driver
@ 2007-12-28 13:01 chripell
2007-12-29 1:38 ` Jan Engelhardt
0 siblings, 1 reply; 5+ messages in thread
From: chripell @ 2007-12-28 13:01 UTC (permalink / raw)
To: linux-kernel; +Cc: Christian Pellegrin
This patch adds support for the MAX3100 SPI UART.
Generated on 20071228 against v2.6.23
Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
---
drivers/serial/Kconfig | 7 +
drivers/serial/Makefile | 1 +
drivers/serial/max3100.c | 987 ++++++++++++++++++++++++++++++++++++++++
include/linux/serial_max3100.h | 28 ++
4 files changed, 1023 insertions(+), 0 deletions(-)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 81b52b7..4e7111b 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -461,6 +461,13 @@ config SERIAL_S3C2410_CONSOLE
your boot loader about how to pass options to the kernel at
boot time.)
+config SERIAL_MAX3100
+ tristate "MAX3100 support"
+ depends on SPI
+ help
+ MAX3100 chip support
+
+
config SERIAL_DZ
bool "DECstation DZ serial driver"
depends on MACH_DECSTATION && 32BIT
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index af6377d..9f67e52 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_SERIAL_PNX8XXX) += pnx8xxx_uart.o
obj-$(CONFIG_SERIAL_SA1100) += sa1100.o
obj-$(CONFIG_SERIAL_BFIN) += bfin_5xx.o
obj-$(CONFIG_SERIAL_S3C2410) += s3c2410.o
+obj-$(CONFIG_SERIAL_MAX3100) += max3100.o
obj-$(CONFIG_SERIAL_SUNCORE) += suncore.o
obj-$(CONFIG_SERIAL_SUNHV) += sunhv.o
obj-$(CONFIG_SERIAL_SUNZILOG) += sunzilog.o
diff --git a/drivers/serial/max3100.c b/drivers/serial/max3100.c
new file mode 100644
index 0000000..7f2c371
--- /dev/null
+++ b/drivers/serial/max3100.c
@@ -0,0 +1,987 @@
+
+/*
+ *
+ * Copyright (C) 2007 Christian Pellegrin <chripell@evolware.org>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ *
+ * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have
+ * to use polling for flow control. TX empty IRQ is unusable, since
+ * writing conf clears FIFO buffer and we cannot have this interrupt
+ * always asking us for attention.
+ *
+ * Example platform data:
+
+static struct plat_max3100 max3100_plat_data = {
+ .loopback = 0,
+ .crystal = 0,
+ .only_edge_irq = 0,
+};
+
+static struct spi_board_info spi_board_info[] = {
+ {
+ .modalias = "max3100",
+ .platform_data = &max3100_plat_data,
+ .irq = IRQ_EINT12,
+ .max_speed_hz = 5*1000*1000,
+ .chip_select = 0,
+ },
+};
+
+ * The initial minor number is 128 to prevent clashes with ttyS:
+ * mknod /dev/ttyMAX0 c 4 128
+ */
+
+#include <linux/bitops.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/keyboard.h>
+#include <linux/major.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/serial_core.h>
+#include <linux/signal.h>
+#include <linux/spi/spi.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+
+#include <asm/system.h>
+
+#include <linux/serial_max3100.h>
+
+#define MAX3100_C (1<<14)
+#define MAX3100_D (0<<14)
+#define MAX3100_W (1<<15)
+#define MAX3100_RX (0<<15)
+
+#define MAX3100_WC (MAX3100_W | MAX3100_C)
+#define MAX3100_RC (MAX3100_RX | MAX3100_C)
+#define MAX3100_WD (MAX3100_W | MAX3100_D)
+#define MAX3100_RD (MAX3100_RX | MAX3100_D)
+#define MAX3100_CMD (3 << 14)
+
+#define MAX3100_T (1<<14)
+#define MAX3100_R (1<<15)
+
+#define MAX3100_FEN (1<<13)
+#define MAX3100_SHDN (1<<12)
+#define MAX3100_TM (1<<11)
+#define MAX3100_RM (1<<10)
+#define MAX3100_PM (1<<9)
+#define MAX3100_RAM (1<<8)
+#define MAX3100_IR (1<<7)
+#define MAX3100_ST (1<<6)
+#define MAX3100_PE (1<<5)
+#define MAX3100_L (1<<4)
+#define MAX3100_BAUD (0xf)
+
+#define MAX3100_TE (1<<10)
+#define MAX3100_RAFE (1<<10)
+#define MAX3100_RTS (1<<9)
+#define MAX3100_CTS (1<<9)
+#define MAX3100_PT (1<<8)
+#define MAX3100_DATA (0xff)
+
+#define MAX3100_RT (MAX3100_R | MAX3100_T)
+#define MAX3100_RTC (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)
+
+struct max3100_port_s {
+ struct uart_port port;
+ struct spi_device *spi;
+ struct tty_struct *tty;
+
+ struct mutex spi_txrx;/* protects access to the hw */
+
+ int rts; /* rts status, can be MAX3100_RTS or 0 */
+ int conf; /* configuration for the MAX31000
+ * (bits 0-7, bits 8-11 are irqs) */
+ int last_cts_rx; /* last CTS received for flow ctrl */
+
+ int tx_buf_cur; /* current char to tx */
+ int tx_buf_tot; /* current number of chars in tx buf */
+ unsigned char *tx_buf;
+ /* shared tx buffer spinlock (no sem
+ * since write may sleep) */
+ spinlock_t tx_buf_lock;
+
+ int tx_stopped:1; /* when we should not send chars */
+ int parity:3; /* keeps track if we should send parity */
+#define MAX3100_PARITY_ON 1
+#define MAX3100_PARITY_ODD 2
+#define MAX3100_7BIT 4
+
+ int irq; /* irq assigned to the max3100 */
+
+ int minor; /* minor number */
+ int crystal:1; /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
+ int loopback:1; /* 1 if we are in loopback mode */
+ int only_edge_irq:1; /* 1 if we have only edge irqs (like PXA) */
+
+ int ref_count; /* how many users */
+ struct mutex sem; /* protects us during open/close */
+
+ /* for handling irqs: need workqueue since we do spi_sync */
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+ /* set to 1 to make the workhandler exit as soon as possible */
+ int force_end_work;
+
+ /* these are for IRQ on/off counting */
+ int irq_status;
+ /* avoid race condition on irq_status */
+ spinlock_t irq_lock;
+
+ /* signals when we done sending current buffer */
+ wait_queue_head_t all_sent;
+
+ /* this is set when we are waking up */
+ int after_suspend:1;
+ /* hook for suspending MAX3100 via dedicated pin */
+ void (*max3100_hw_suspend) (int suspend);
+};
+
+/* global since we do register the driver only once */
+static struct tty_driver *serial_driver;
+
+/* 4 MAX3100s should be enough for everyone */
+#define MAX_MAX3100 4
+static struct max3100_port_s *max3100s[MAX_MAX3100]; /* the chips */
+
+/* our buffer for sending chars */
+#define MAX3100_TX_BUF_N 16
+
+/* how many chars we wait befor flipping tty buffer */
+#define MAX3100_FLIP_EVERY 8
+
+static void irq_state(struct max3100_port_s *s, int on)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->irq_lock, flags);
+ if (s->irq_status != on) {
+ if (on)
+ enable_irq(s->irq);
+ else
+ disable_irq(s->irq);
+ s->irq_status = on;
+ }
+ spin_unlock_irqrestore(&s->irq_lock, flags);
+}
+
+
+static int max3100_do_parity(struct max3100_port_s *s, u16 c)
+{
+ int parity;
+ int i, n;
+
+ if (s->parity & MAX3100_PARITY_ODD)
+ parity = 0;
+ else
+ parity = 1;
+
+ if (s->parity & MAX3100_7BIT)
+ n = 7;
+ else
+ n = 8;
+
+ for (i = 0; i < n; i++)
+ parity = parity ^ ((c>>i) & 1);
+ return parity;
+}
+
+static int max3100_check_parity(struct max3100_port_s *s, u16 c)
+{
+ return max3100_do_parity(s, c) == ((c>>9) & 1);
+}
+
+static void max3100_calc_parity(struct max3100_port_s *s, u16 *c)
+{
+ *c &= ~MAX3100_PT;
+ *c |= max3100_do_parity(s, *c)<<8;
+}
+
+
+static void max3100_work(struct work_struct *w);
+
+static void max3100_dowork(struct max3100_port_s *s)
+{
+ if (!s->force_end_work) {
+ PREPARE_WORK(&s->work, max3100_work);
+ queue_work(s->workqueue, &s->work);
+ }
+}
+
+static int max3100_sr(struct max3100_port_s *s, u16 tx, u16 *rx, int push)
+{
+ /* note: we suppose that the T bit from conf_status is in sync
+ * with the hw one, so all the communication must go through
+ * this function */
+ struct spi_message message;
+ struct spi_transfer tran;
+ int status, flag;
+ u16 etx, erx;
+ int got_char = 0;
+
+ mutex_lock(&s->spi_txrx);
+
+ if (s->loopback) {
+ if ((tx & MAX3100_CMD) == MAX3100_RC)
+ tx |= 1;
+ }
+ etx = htons(tx);
+ spi_message_init(&message);
+ memset(&tran, 0, sizeof(tran));
+ tran.tx_buf = &etx;
+ tran.rx_buf = &erx;
+ tran.len = 2;
+ spi_message_add_tail(&tran, &message);
+ status = spi_sync(s->spi, &message);
+ if (status) {
+ dev_warn(&s->spi->dev, "error while calling spi_sync\n");
+ mutex_unlock(&s->spi_txrx);
+ return 0;
+ }
+ *rx = ntohs(erx);
+ dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);
+
+ if ((tx & MAX3100_CMD) == MAX3100_RD ||
+ (tx & MAX3100_CMD) == MAX3100_WD)
+ s->last_cts_rx = *rx;
+
+ if (*rx & MAX3100_R &&
+ ((tx & MAX3100_CMD) == MAX3100_RD ||
+ (tx & MAX3100_CMD) == MAX3100_WD)) {
+ got_char = 1;
+ if (tty_buffer_request_room(s->tty, 1) == 0) {
+ dev_warn(&s->spi->dev, "no room in tty buffer\n");
+ tty_schedule_flip(s->tty);
+ }
+
+ flag = TTY_NORMAL;
+ if (*rx & MAX3100_RAFE) {
+ s->port.icount.frame++;
+ flag = TTY_FRAME;
+ }
+ if (s->parity & MAX3100_PARITY_ON &&
+ max3100_check_parity(s, *rx)) {
+ s->port.icount.parity++;
+ flag = TTY_PARITY;
+ }
+ tty_insert_flip_char(s->tty, *rx & MAX3100_DATA, flag);
+ }
+
+ mutex_unlock(&s->spi_txrx);
+
+ if (push && got_char)
+ tty_schedule_flip(s->tty);
+ return got_char;
+}
+
+
+static void max3100_send_conf(struct max3100_port_s *s)
+{
+ u16 tx = 0, rx;
+
+ tx = MAX3100_WC | (s->conf & 0x0fff);
+ max3100_sr(s, tx, &rx, 1);
+}
+
+static int max3100_ok_to_send(struct max3100_port_s *s)
+{
+ if (C_CRTSCTS(s->tty) && (s->last_cts_rx & MAX3100_CTS) == 0)
+ return 0;
+ return !s->tx_stopped;
+}
+
+static void max3100_work(struct work_struct *w)
+{
+ struct max3100_port_s *s = container_of(w, struct max3100_port_s, work);
+ u16 tx, rx;
+ int nchars; /* number of char waiting in the send buf */
+ int rxchars = 0; /* chars received */
+
+ do {
+ unsigned long flags;
+
+ if (s->after_suspend) {
+ mdelay(25);
+ max3100_send_conf(s);
+ mdelay(25);
+ s->after_suspend = 0;
+ }
+
+ tx = MAX3100_RD;
+ /* rx a char so we get MAX3100_T and CTS current */
+ rxchars += max3100_sr(s, tx, &rx, 0);
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ nchars = s->tx_buf_tot - s->tx_buf_cur;
+ tx = MAX3100_WD | s->rts;
+ tx |= s->tx_buf[s->tx_buf_cur];
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+
+ if ((rx & MAX3100_T) && /* tx buffer empty*/
+ max3100_ok_to_send(s) && /* fw ctrl decision */
+ nchars > 0 && /* more to send */
+ !s->force_end_work) {
+ if (s->parity & MAX3100_PARITY_ON)
+ max3100_calc_parity(s, &tx);
+ rxchars += max3100_sr(s, tx, &rx, 0);
+ nchars -= 1;
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ s->tx_buf_cur += 1;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ if (nchars == 0) {
+ tty_wakeup(s->tty);
+ wake_up(&s->all_sent);
+ }
+ }
+ if (rxchars > MAX3100_FLIP_EVERY) {
+ tty_schedule_flip(s->tty);
+ rxchars = 0;
+ }
+ }
+ while ((nchars > 0 || /* more to send */
+ rx & MAX3100_R) && /* try to empy all the RX buffer */
+ !s->force_end_work);
+ if (rxchars)
+ tty_schedule_flip(s->tty);
+ if (!s->only_edge_irq && !s->force_end_work)
+ irq_state(s, 1);
+}
+
+static irqreturn_t max3100_irq(int irqno, void *dev_id)
+{
+ struct max3100_port_s *s = dev_id;
+
+ if (!s->only_edge_irq)
+ irq_state(s, 0); /* avoid irq storm */
+ max3100_dowork(s);
+ return IRQ_HANDLED;
+}
+
+static void rs_stop(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ s->tx_stopped = 1;
+}
+
+static void rs_start(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ s->tx_stopped = 0;
+}
+
+static void rs_flush_chars(struct tty_struct *tty)
+{
+}
+
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ wait_event_timeout(s->all_sent,
+ s->tx_buf_tot == 0 || s->tx_buf_tot == s->tx_buf_cur,
+ timeout);
+}
+
+static void rs_flush_buffer(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = 0;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+}
+
+static int rs_write(struct tty_struct *tty,
+ const unsigned char *buf, int count)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_cur < s->tx_buf_tot) {
+ count = 0;
+ } else {
+ if (count > MAX3100_TX_BUF_N)
+ count = MAX3100_TX_BUF_N;
+ memcpy(s->tx_buf, buf, count);
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = count;
+ }
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ max3100_dowork(s);
+ return count;
+}
+
+static int rs_write_room(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_cur < s->tx_buf_tot)
+ ret = 0;
+ else
+ ret = MAX3100_TX_BUF_N;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ return ret;
+}
+
+static int rs_chars_in_buffer(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_cur < s->tx_buf_tot)
+ ret = MAX3100_TX_BUF_N;
+ else
+ ret = 0;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ return ret;
+}
+
+static void internal_throttle(struct tty_struct *tty, char ch, int rts)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ u16 tx = 0, rx;
+ int old_tx_stopped;
+
+ old_tx_stopped = s->tx_stopped;
+ s->tx_stopped = 1;
+ tx = MAX3100_RD;
+ /* wait for tx buf empty. Unfortunately we cannot avoid a busy
+ loop (it should not take much since we block tx ... so at
+ most a byte time) since TX empty interrupt is unusable (see
+ Notes on top) */
+ do {
+ max3100_sr(s, tx, &rx, 1);
+ if ((rx & MAX3100_T) == 0)
+ schedule();
+ } while ((rx & MAX3100_T) == 0);
+
+ if (I_IXOFF(tty))
+ tx = MAX3100_WD | s->rts | (ch&0xff);
+ if (C_CRTSCTS(tty)) {
+ s->rts = rts ? (MAX3100_RTS) : 0;
+ tx = MAX3100_WD | s->rts | MAX3100_TE;
+ }
+ if (tx)
+ max3100_sr(s, tx, &rx, 1);
+ s->tx_stopped = old_tx_stopped;
+ max3100_dowork(s);
+}
+
+static void rs_throttle(struct tty_struct *tty)
+{
+ internal_throttle(tty, STOP_CHAR(tty), 0);
+}
+
+static void rs_unthrottle(struct tty_struct *tty)
+{
+ internal_throttle(tty, START_CHAR(tty), 1);
+}
+
+static int get_lsr_info(struct max3100_port_s *s, unsigned int *value)
+{
+ unsigned char status;
+ u16 tx = 0, rx;
+
+ tx = MAX3100_RD;
+ max3100_sr(s, tx, &rx, 1);
+ status = (rx & MAX3100_CTS) > 0;
+ return put_user(status, value);
+}
+
+static int rs_ioctl(struct tty_struct *tty, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int retval = 0;
+
+ switch (cmd) {
+
+ case TIOCSERGETLSR: /* Get line status register */
+ return get_lsr_info(s, (unsigned int *) arg);
+
+ default:
+ retval = -ENOIOCTLCMD ;
+ }
+ return retval;
+}
+
+static void change_speed(struct max3100_port_s *s)
+{
+ unsigned cflag;
+ unsigned i;
+ u32 param_new;
+ u32 param_mask;
+
+ cflag = s->tty->termios->c_cflag;
+ param_new = 0;
+ param_mask = 0;
+
+ i = cflag & CBAUD;
+ switch (i) {
+ case B300:
+ if (s->crystal) {
+ param_new = 16;
+ } else {
+ dev_warn(&s->spi->dev, "unsupported baud rate!\n");
+ param_new = 15;
+ }
+ break;
+ case B600:
+ param_new = 15;
+ break;
+ case B1200:
+ param_new = 14;
+ break;
+ case B2400:
+ param_new = 13;
+ break;
+ case B4800:
+ param_new = 12;
+ break;
+ case B9600:
+ param_new = 11;
+ break;
+ case B19200:
+ param_new = 10;
+ break;
+ case B38400:
+ param_new = 9;
+ break;
+ case B57600:
+ param_new = 2;
+ break;
+ case B115200:
+ param_new = 1;
+ break;
+ case B230400:
+ if (s->crystal) {
+ param_new = 1;
+ dev_warn(&s->spi->dev, "unsupported baud rate!\n");
+ } else {
+ param_new = 0;
+ }
+ break;
+ default:
+ param_new = 1;
+ dev_warn(&s->spi->dev, "invalid baudrate\n");
+ }
+ param_new = (param_new - s->crystal) & MAX3100_BAUD;
+ param_mask |= MAX3100_BAUD;
+
+ if ((cflag & CSIZE) == CS8) {
+ param_new &= ~MAX3100_L;
+ s->parity &= ~MAX3100_7BIT;
+ } else {
+ param_new |= MAX3100_L;
+ s->parity |= MAX3100_7BIT;
+ }
+ param_mask |= MAX3100_L;
+
+ if (cflag & CSTOPB)
+ param_new |= MAX3100_ST;
+ else
+ param_new &= ~MAX3100_ST;
+ param_mask |= MAX3100_ST;
+
+ if (cflag & PARENB) {
+ param_new |= MAX3100_PE;
+ s->parity |= MAX3100_PARITY_ON;
+ } else {
+ param_new &= ~MAX3100_PE;
+ s->parity &= ~MAX3100_PARITY_ON;
+ }
+ param_mask |= MAX3100_PE;
+
+ if (cflag & PARODD) {
+ s->parity |= MAX3100_PARITY_ODD;
+ } else {
+ s->parity &= ~MAX3100_PARITY_ODD;
+ }
+
+ s->conf = (s->conf & ~param_mask) | (param_new & param_mask);
+ max3100_send_conf(s);
+
+ return;
+}
+
+
+static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ if (tty->termios->c_cflag == old_termios->c_cflag)
+ return;
+
+ change_speed(s);
+
+ if ((old_termios->c_cflag & CRTSCTS) &&
+ !(tty->termios->c_cflag & CRTSCTS))
+ max3100_dowork(s);
+}
+
+static void shutdown(struct max3100_port_s *s)
+{
+ u16 tx, rx;
+
+ s->force_end_work = 1;
+ if (s->workqueue) {
+ flush_workqueue(s->workqueue);
+ destroy_workqueue(s->workqueue);
+ }
+ if (s->irq)
+ free_irq(s->irq, s);
+ kfree(s->tx_buf);
+ s->tx_buf = NULL;
+ if (s->tty)
+ set_bit(TTY_IO_ERROR, &s->tty->flags);
+ /* set shutdown mode to save power */
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(s, tx, &rx, 0);
+}
+
+static void rs_hangup(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ shutdown(s);
+}
+
+static int startup(struct max3100_port_s *s)
+{
+ char b[10];
+ int irq_type;
+
+ s->tx_buf = kmalloc(MAX3100_TX_BUF_N, GFP_KERNEL);
+ if (s->tx_buf == NULL)
+ return -ENOMEM;
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = 0;
+
+ s->force_end_work = 0;
+ s->parity = 0;
+ s->rts = 0;
+ s->tx_stopped = 0;
+ s->conf = MAX3100_RM;
+
+ sprintf(b, "max3100-%d", s->minor);
+ s->workqueue = create_singlethread_workqueue(b);
+ if (!s->workqueue) {
+ dev_warn(&s->spi->dev, "cannot create workqueue\n");
+ return -EBUSY;
+ }
+ INIT_WORK(&s->work, max3100_work);
+
+ s->irq_status = 1; /* IRQS are on after request */
+ if (s->only_edge_irq)
+ irq_type = IRQF_TRIGGER_FALLING;
+ else
+ irq_type = IRQF_TRIGGER_LOW;
+ if (request_irq(s->irq, max3100_irq, irq_type, "max3100", s) < 0) {
+ dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
+ s->irq = 0;
+ kfree(s->tx_buf);
+ return -EBUSY;
+ }
+
+ if (s->tty)
+ clear_bit(TTY_IO_ERROR, &s->tty->flags);
+
+ change_speed(s);
+ mdelay(50); /* waits for wakeup from shutdown */
+
+ if (s->loopback) {
+ u16 tx, rx;
+ tx = 0x4001;
+ max3100_sr(s, tx, &rx, 1);
+ }
+
+ return 0;
+}
+
+int rs_open(struct tty_struct *tty, struct file *filp)
+{
+ struct max3100_port_s *s;
+ int retval = 0, line;
+
+ line = tty->index;
+
+ if (line >= MAX_MAX3100 || line < 0)
+ return -ENODEV;
+
+ s = max3100s[line];
+
+ if (!s) {
+ printk(KERN_ERR "Nonexistent max3100 for index %d\n", line);
+ return -ENODEV;
+ }
+
+ retval = mutex_lock_interruptible(&s->sem);
+ if (retval < 0)
+ return retval;
+
+ s->ref_count++;
+
+ if (s->ref_count == 1) {
+ tty->driver_data = s;
+ s->tty = tty;
+
+ retval = startup(s);
+ }
+
+ mutex_unlock(&s->sem);
+
+ return retval;
+}
+
+static void rs_close(struct tty_struct *tty, struct file *filp)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ mutex_lock(&s->sem);
+
+ s->ref_count--;
+ if (s->ref_count == 0)
+ shutdown(s);
+
+ mutex_unlock(&s->sem);
+}
+
+static int rs_tiocmget(struct tty_struct *tty, struct file *file)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ u16 tx, rx;
+ unsigned int result;
+
+ tx = MAX3100_RD;
+ max3100_sr(s, tx, &rx, 1);
+
+ result = ((s->rts) ? TIOCM_RTS : 0)
+ | ((rx & MAX3100_CTS) ? TIOCM_CTS : 0);
+ return result;
+}
+
+static int rs_tiocmset(struct tty_struct *tty, struct file *file,
+ unsigned int set, unsigned int clear)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int old_rts = s->rts;
+ u16 tx, rx;
+
+ if (set & TIOCM_RTS)
+ s->rts = MAX3100_RTS;
+ if (clear & TIOCM_RTS)
+ s->rts = 0;
+
+ if (s->rts != old_rts) {
+ tx = MAX3100_WD | s->rts | MAX3100_TE;
+ max3100_sr(s, tx, &rx, 1);
+ }
+ return 0;
+}
+
+static struct tty_operations rs_ops = {
+ .open = rs_open,
+ .close = rs_close,
+ .write = rs_write,
+ .flush_chars = rs_flush_chars,
+ .wait_until_sent = rs_wait_until_sent,
+ .write_room = rs_write_room,
+ .chars_in_buffer = rs_chars_in_buffer,
+ .flush_buffer = rs_flush_buffer,
+ .ioctl = rs_ioctl,
+ .throttle = rs_throttle,
+ .unthrottle = rs_unthrottle,
+ .set_termios = rs_set_termios,
+ .stop = rs_stop,
+ .start = rs_start,
+ .hangup = rs_hangup,
+ .tiocmget = rs_tiocmget,
+ .tiocmset = rs_tiocmset,
+};
+
+static int __devinit max3100_probe(struct spi_device *spi)
+{
+ int i;
+ struct plat_max3100 *pdata;
+ u16 tx, rx;
+
+ if (!serial_driver) {
+ serial_driver = alloc_tty_driver(MAX_MAX3100);
+ if (!serial_driver) {
+ printk(KERN_ERR "Cannot allocate serial driver\n");
+ return -ENOMEM;
+ }
+
+ serial_driver->name = "ttyMAX";
+ serial_driver->driver_name = "ttyMAX";
+ serial_driver->major = TTY_MAJOR;
+ /* this should prevent clashes */
+ serial_driver->minor_start = 128;
+ serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ serial_driver->subtype = SERIAL_TYPE_NORMAL;
+ serial_driver->init_termios = tty_std_termios;
+ serial_driver->init_termios.c_cflag =
+ B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ serial_driver->flags = TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_DEV;
+ tty_set_operations(serial_driver, &rs_ops);
+
+ if (tty_register_driver(serial_driver)) {
+ put_tty_driver(serial_driver);
+ printk(KERN_ERR "Couldn't register serial driver\n");
+ return -EINVAL;
+ }
+ }
+
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (!max3100s[i])
+ break;
+ if (i == MAX_MAX3100) {
+ dev_warn(&spi->dev, "too many MAX3100 chips\n");
+ return -ENOMEM;
+ }
+
+ max3100s[i] = kzalloc(sizeof(struct max3100_port_s), GFP_KERNEL);
+ if (!max3100s[i]) {
+ dev_warn(&spi->dev,
+ "kmalloc for max3100 structure %d failed!\n", i);
+ return -ENOMEM;
+ }
+ max3100s[i]->spi = spi;
+ max3100s[i]->irq = spi->irq;
+ mutex_init(&max3100s[i]->sem);
+ mutex_init(&max3100s[i]->spi_txrx);
+ spin_lock_init(&max3100s[i]->tx_buf_lock);
+ spin_lock_init(&max3100s[i]->irq_lock);
+ init_waitqueue_head(&max3100s[i]->all_sent);
+ dev_set_drvdata(&spi->dev, max3100s[i]);
+ pdata = spi->dev.platform_data;
+ max3100s[i]->crystal = pdata->crystal;
+ max3100s[i]->loopback = pdata->loopback;
+ max3100s[i]->only_edge_irq = pdata->only_edge_irq;
+ max3100s[i]->after_suspend = 0;
+ max3100s[i]->max3100_hw_suspend = pdata->max3100_hw_suspend;
+ max3100s[i]->minor = i;
+ tty_register_device(serial_driver, i, &spi->dev);
+ /* set shutdown mode to save power. Will be woken-up on open */
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(max3100s[i], tx, &rx, 0);
+
+ return 0;
+}
+
+static int __devexit max3100_remove(struct spi_device *spi)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+ int i;
+
+ if (s->ref_count > 0)
+ return -EBUSY;
+
+ /* find out the index for the chip we are removing */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i] == s)
+ break;
+
+ tty_unregister_device(serial_driver, i);
+ kfree(max3100s[i]);
+ max3100s[i] = NULL;
+
+ /* check if this is the last chip we have */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i])
+ return 0;
+ tty_unregister_driver(serial_driver);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int max3100_suspend(struct spi_device *spi, pm_message_t state)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+
+ synchronize_irq(s->irq);
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(1);
+ return 0;
+}
+
+static int max3100_resume(struct spi_device *spi)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+
+ if (s->max3100_hw_suspend) {
+ s->max3100_hw_suspend(0);
+ s->after_suspend = 1;
+ max3100_dowork(s);
+ }
+ return 0;
+}
+
+#else
+#define max3100_suspend NULL
+#define max3100_resume NULL
+#endif
+
+static struct spi_driver max3100_driver = {
+ .driver = {
+ .name = "max3100",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+
+ .probe = max3100_probe,
+ .remove = __devexit_p(max3100_remove),
+ .suspend = max3100_suspend,
+ .resume = max3100_resume,
+};
+
+
+static int __init max3100_init(void)
+{
+ return spi_register_driver(&max3100_driver);
+}
+module_init(max3100_init);
+
+static void __exit max3100_exit(void)
+{
+ spi_unregister_driver(&max3100_driver);
+}
+module_exit(max3100_exit);
+
+MODULE_DESCRIPTION("MAX3100 driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/serial_max3100.h b/include/linux/serial_max3100.h
new file mode 100644
index 0000000..5c0489e
--- /dev/null
+++ b/include/linux/serial_max3100.h
@@ -0,0 +1,28 @@
+
+/*
+ *
+ * Copyright (C) 2007 Christian Pellegrin
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+
+#ifndef _LINUX_SERIAL_MAX3100_H
+#define _LINUX_SERIAL_MAX3100_H 1
+
+struct plat_max3100 {
+/* force MAX3100 in loopback */
+ int loopback;
+/* 0 for 3.6864 Mhz, 1 for 1.8432 */
+ int crystal;
+/* for archs like PXA with only edge irqs */
+ int only_edge_irq;
+/* MAX3100 has a shutdown pin. This is a hook
+ called on suspend and resume to activate it.*/
+ void (*max3100_hw_suspend) (int suspend);
+};
+
+#endif
--
1.4.4.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] max3100 driver
2007-12-28 13:01 [PATCH RESEND] max3100 driver chripell
@ 2007-12-29 1:38 ` Jan Engelhardt
2007-12-29 6:34 ` chri
0 siblings, 1 reply; 5+ messages in thread
From: Jan Engelhardt @ 2007-12-29 1:38 UTC (permalink / raw)
To: chripell; +Cc: linux-kernel, Christian Pellegrin
On Dec 28 2007 14:01, chripell@gmail.com wrote:
>+
>+ * The initial minor number is 128 to prevent clashes with ttyS:
>+ * mknod /dev/ttyMAX0 c 4 128
>+ */
[4:128] is taken by ttyS64. Please look into Documentation/devices.txt.
>+struct max3100_port_s {
>+ struct uart_port port;
>+ struct spi_device *spi;
>+ struct tty_struct *tty;
>+
>+ struct mutex spi_txrx;/* protects access to the hw */
>+
>+ int rts; /* rts status, can be MAX3100_RTS or 0 */
possibly be bool then, if it only takes on two values?
>+ int conf; /* configuration for the MAX31000
>+ * (bits 0-7, bits 8-11 are irqs) */
>+ int last_cts_rx; /* last CTS received for flow ctrl */
>+
>+ int tx_buf_cur; /* current char to tx */
>+ int tx_buf_tot; /* current number of chars in tx buf */
Probably unsigned?
>+static int max3100_do_parity(struct max3100_port_s *s, u16 c)
>+{
>+ int parity;
>+ int i, n;
>+
>+ if (s->parity & MAX3100_PARITY_ODD)
>+ parity = 0;
>+ else
>+ parity = 1;
Or
parity = !!(s->parity & MAX3100_PARITY_ODD);
n = (s->parity & MAX3100_7BIT) ? 7 : 8;
(up to you)
>+ for (i = 0; i < n; i++)
>+ parity = parity ^ ((c>>i) & 1);
parity ^= (c >> i) & 1;
>+ return parity;
>+}
>+
>+ if (s->loopback) {
>+ if ((tx & MAX3100_CMD) == MAX3100_RC)
>+ tx |= 1;
>+ }
if (s->loopback && (tx & MAX3100_CMD) == MAX3100_RC)
tx |= 1;
>+MODULE_DESCRIPTION("MAX3100 driver");
>+MODULE_LICENSE("GPL");
I notice a steep increase in serial drivers. Everyone got their
new chips for xmas, eh? :)
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] max3100 driver
2007-12-29 1:38 ` Jan Engelhardt
@ 2007-12-29 6:34 ` chri
2007-12-29 10:27 ` chripell
0 siblings, 1 reply; 5+ messages in thread
From: chri @ 2007-12-29 6:34 UTC (permalink / raw)
To: Jan Engelhardt; +Cc: linux-kernel
Hi,
On Dec 29, 2007 2:38 AM, Jan Engelhardt <jengelh@computergmbh.de> wrote:
>
> [4:128] is taken by ttyS64. Please look into Documentation/devices.txt.
>
I did it but I think it's better to reuse a minor from ttyS than
allocating a new major (64 serial ports is a lot). I saw that other
drivers take a similar approach, just tend to stay away from low
numbers that are used by 8250 and its child (that can be connected
more or less everywhere). Perhaps in these udev times the serial
minor number should be allocated dinamicaly. Do you think this makes
sense?
>
> I notice a steep increase in serial drivers. Everyone got their
> new chips for xmas, eh? :)
>
>
This year I was a bad boy so Santa brought me just a cheap uart. For
next Xmas I hope in a WLAN chip or something like that. ;-)
--
Christian Pellegrin, see http://www.evolware.org/chri/
"Real Programmers don't play tennis, or any other sport which requires
you to change clothes. Mountain climbing is OK, and Real Programmers
wear their climbing boots to work in case a mountain should suddenly
spring up in the middle of the computer room."
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH RESEND] max3100 driver
2007-12-29 6:34 ` chri
@ 2007-12-29 10:27 ` chripell
0 siblings, 0 replies; 5+ messages in thread
From: chripell @ 2007-12-29 10:27 UTC (permalink / raw)
To: linux-kernel; +Cc: Christian Pellegrin
This patch adds support for the MAX3100 SPI UART.
Generated on 20071229 against v2.6.23
Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
---
drivers/serial/Kconfig | 7 +
drivers/serial/Makefile | 1 +
drivers/serial/max3100.c | 1003 ++++++++++++++++++++++++++++++++++++++++
include/linux/serial_max3100.h | 28 ++
4 files changed, 1039 insertions(+), 0 deletions(-)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 81b52b7..4e7111b 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -461,6 +461,13 @@ config SERIAL_S3C2410_CONSOLE
your boot loader about how to pass options to the kernel at
boot time.)
+config SERIAL_MAX3100
+ tristate "MAX3100 support"
+ depends on SPI
+ help
+ MAX3100 chip support
+
+
config SERIAL_DZ
bool "DECstation DZ serial driver"
depends on MACH_DECSTATION && 32BIT
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index af6377d..9f67e52 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_SERIAL_PNX8XXX) += pnx8xxx_uart.o
obj-$(CONFIG_SERIAL_SA1100) += sa1100.o
obj-$(CONFIG_SERIAL_BFIN) += bfin_5xx.o
obj-$(CONFIG_SERIAL_S3C2410) += s3c2410.o
+obj-$(CONFIG_SERIAL_MAX3100) += max3100.o
obj-$(CONFIG_SERIAL_SUNCORE) += suncore.o
obj-$(CONFIG_SERIAL_SUNHV) += sunhv.o
obj-$(CONFIG_SERIAL_SUNZILOG) += sunzilog.o
diff --git a/drivers/serial/max3100.c b/drivers/serial/max3100.c
new file mode 100644
index 0000000..9b6a08c
--- /dev/null
+++ b/drivers/serial/max3100.c
@@ -0,0 +1,1003 @@
+
+/*
+ *
+ * Copyright (C) 2007 Christian Pellegrin <chripell@evolware.org>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ *
+ * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have
+ * to use polling for flow control. TX empty IRQ is unusable, since
+ * writing conf clears FIFO buffer and we cannot have this interrupt
+ * always asking us for attention.
+ *
+ * Example platform data:
+
+static struct plat_max3100 max3100_plat_data = {
+ .loopback = 0,
+ .crystal = 0,
+ .only_edge_irq = 0,
+};
+
+static struct spi_board_info spi_board_info[] = {
+ {
+ .modalias = "max3100",
+ .platform_data = &max3100_plat_data,
+ .irq = IRQ_EINT12,
+ .max_speed_hz = 5*1000*1000,
+ .chip_select = 0,
+ },
+};
+
+ * The initial minor number is 128 to prevent clashes with ttyS:
+ * mknod /dev/ttyMAX0 c 4 128
+ */
+
+#include <linux/bitops.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/keyboard.h>
+#include <linux/major.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/serial_core.h>
+#include <linux/signal.h>
+#include <linux/spi/spi.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+
+#include <asm/system.h>
+
+#include <linux/serial_max3100.h>
+
+#define MAX3100_C (1<<14)
+#define MAX3100_D (0<<14)
+#define MAX3100_W (1<<15)
+#define MAX3100_RX (0<<15)
+
+#define MAX3100_WC (MAX3100_W | MAX3100_C)
+#define MAX3100_RC (MAX3100_RX | MAX3100_C)
+#define MAX3100_WD (MAX3100_W | MAX3100_D)
+#define MAX3100_RD (MAX3100_RX | MAX3100_D)
+#define MAX3100_CMD (3 << 14)
+
+#define MAX3100_T (1<<14)
+#define MAX3100_R (1<<15)
+
+#define MAX3100_FEN (1<<13)
+#define MAX3100_SHDN (1<<12)
+#define MAX3100_TM (1<<11)
+#define MAX3100_RM (1<<10)
+#define MAX3100_PM (1<<9)
+#define MAX3100_RAM (1<<8)
+#define MAX3100_IR (1<<7)
+#define MAX3100_ST (1<<6)
+#define MAX3100_PE (1<<5)
+#define MAX3100_L (1<<4)
+#define MAX3100_BAUD (0xf)
+
+#define MAX3100_TE (1<<10)
+#define MAX3100_RAFE (1<<10)
+#define MAX3100_RTS (1<<9)
+#define MAX3100_CTS (1<<9)
+#define MAX3100_PT (1<<8)
+#define MAX3100_DATA (0xff)
+
+#define MAX3100_RT (MAX3100_R | MAX3100_T)
+#define MAX3100_RTC (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)
+
+struct max3100_port_s {
+ struct uart_port port;
+ struct spi_device *spi;
+ struct tty_struct *tty;
+
+ struct mutex spi_txrx;/* protects access to the hw */
+
+ int rts:1; /* rts status */
+ int conf; /* configuration for the MAX31000
+ * (bits 0-7, bits 8-11 are irqs) */
+ int last_cts_rx; /* last CTS received for flow ctrl */
+
+ unsigned int tx_buf_cur; /* current char to tx */
+ /* current number of chars in tx buf */
+ unsigned int tx_buf_tot;
+ unsigned char *tx_buf;
+ /* shared tx buffer spinlock (no sem since write may sleep) */
+ spinlock_t tx_buf_lock;
+
+ int tx_stopped:1; /* when we should not send chars */
+ int parity:3; /* keeps track if we should send parity */
+#define MAX3100_PARITY_ON 1
+#define MAX3100_PARITY_ODD 2
+#define MAX3100_7BIT 4
+
+ int irq; /* irq assigned to the max3100 */
+
+ int minor; /* minor number */
+ int crystal:1; /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
+ int loopback:1; /* 1 if we are in loopback mode */
+ int only_edge_irq:1; /* 1 if we have only edge irqs (like PXA) */
+
+ int ref_count; /* how many users */
+ struct mutex sem; /* protects us during open/close */
+
+ /* for handling irqs: need workqueue since we do spi_sync */
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+ /* set to 1 to make the workhandler exit as soon as possible */
+ int force_end_work;
+
+ /* these are for IRQ on/off counting */
+ int irq_status;
+ /* avoid race condition on irq_status */
+ spinlock_t irq_lock;
+
+ /* signals when we done sending current buffer */
+ wait_queue_head_t all_sent;
+
+ /* this is set when we are waking up */
+ int after_suspend:1;
+ /* hook for suspending MAX3100 via dedicated pin */
+ void (*max3100_hw_suspend) (int suspend);
+};
+
+/* global since we do register the driver only once */
+static struct tty_driver *serial_driver;
+
+/* 4 MAX3100s should be enough for everyone */
+#define MAX_MAX3100 4
+static struct max3100_port_s *max3100s[MAX_MAX3100]; /* the chips */
+
+/* our buffer for sending chars */
+#define MAX3100_TX_BUF_N 16
+
+/* how many chars we wait befor flipping tty buffer */
+#define MAX3100_FLIP_EVERY 8
+
+static void irq_state(struct max3100_port_s *s, int on)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->irq_lock, flags);
+ if (s->irq_status != on) {
+ if (on)
+ enable_irq(s->irq);
+ else
+ disable_irq(s->irq);
+ s->irq_status = on;
+ }
+ spin_unlock_irqrestore(&s->irq_lock, flags);
+}
+
+
+static int max3100_do_parity(struct max3100_port_s *s, u16 c)
+{
+ int parity;
+ int i, n;
+
+ if (s->parity & MAX3100_PARITY_ODD)
+ parity = 0;
+ else
+ parity = 1;
+
+ if (s->parity & MAX3100_7BIT)
+ n = 7;
+ else
+ n = 8;
+
+ for (i = 0; i < n; i++)
+ parity = parity ^ ((c>>i) & 1);
+ return parity;
+}
+
+static int max3100_check_parity(struct max3100_port_s *s, u16 c)
+{
+ return max3100_do_parity(s, c) == ((c>>9) & 1);
+}
+
+static void max3100_calc_parity(struct max3100_port_s *s, u16 *c)
+{
+ *c &= ~MAX3100_PT;
+ *c |= max3100_do_parity(s, *c)<<8;
+}
+
+
+static void max3100_work(struct work_struct *w);
+
+static void max3100_dowork(struct max3100_port_s *s)
+{
+ if (!s->force_end_work) {
+ PREPARE_WORK(&s->work, max3100_work);
+ queue_work(s->workqueue, &s->work);
+ }
+}
+
+static int max3100_sr(struct max3100_port_s *s, u16 tx, u16 *rx, int push)
+{
+ /* note: we suppose that the T bit from conf_status is in sync
+ * with the hw one, so all the communication must go through
+ * this function */
+ struct spi_message message;
+ struct spi_transfer tran;
+ int status, flag;
+ u16 etx, erx;
+ int got_char = 0;
+
+ mutex_lock(&s->spi_txrx);
+
+ if (s->loopback && (tx & MAX3100_CMD) == MAX3100_RC)
+ tx |= 1;
+ etx = htons(tx);
+ spi_message_init(&message);
+ memset(&tran, 0, sizeof(tran));
+ tran.tx_buf = &etx;
+ tran.rx_buf = &erx;
+ tran.len = 2;
+ spi_message_add_tail(&tran, &message);
+ status = spi_sync(s->spi, &message);
+ if (status) {
+ dev_warn(&s->spi->dev, "error while calling spi_sync\n");
+ mutex_unlock(&s->spi_txrx);
+ return 0;
+ }
+ *rx = ntohs(erx);
+ dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);
+
+ if ((tx & MAX3100_CMD) == MAX3100_RD ||
+ (tx & MAX3100_CMD) == MAX3100_WD)
+ s->last_cts_rx = *rx;
+
+ if (*rx & MAX3100_R &&
+ ((tx & MAX3100_CMD) == MAX3100_RD ||
+ (tx & MAX3100_CMD) == MAX3100_WD)) {
+ got_char = 1;
+ if (tty_buffer_request_room(s->tty, 1) == 0) {
+ dev_warn(&s->spi->dev, "no room in tty buffer\n");
+ tty_schedule_flip(s->tty);
+ }
+
+ flag = TTY_NORMAL;
+ if (*rx & MAX3100_RAFE) {
+ s->port.icount.frame++;
+ flag = TTY_FRAME;
+ }
+ if (s->parity & MAX3100_PARITY_ON &&
+ max3100_check_parity(s, *rx)) {
+ s->port.icount.parity++;
+ flag = TTY_PARITY;
+ }
+ tty_insert_flip_char(s->tty, *rx & MAX3100_DATA, flag);
+ }
+
+ mutex_unlock(&s->spi_txrx);
+
+ if (push && got_char)
+ tty_schedule_flip(s->tty);
+ return got_char;
+}
+
+
+static void max3100_send_conf(struct max3100_port_s *s)
+{
+ u16 tx = 0, rx;
+
+ tx = MAX3100_WC | (s->conf & 0x0fff);
+ max3100_sr(s, tx, &rx, 1);
+}
+
+static int max3100_ok_to_send(struct max3100_port_s *s)
+{
+ if (C_CRTSCTS(s->tty) && (s->last_cts_rx & MAX3100_CTS) == 0)
+ return 0;
+ return !s->tx_stopped;
+}
+
+static void max3100_work(struct work_struct *w)
+{
+ struct max3100_port_s *s = container_of(w, struct max3100_port_s, work);
+ u16 tx, rx;
+ int nchars; /* number of char waiting in the send buf */
+ int rxchars = 0; /* chars received */
+
+ do {
+ unsigned long flags;
+
+ if (s->after_suspend) {
+ mdelay(25);
+ max3100_send_conf(s);
+ mdelay(25);
+ s->after_suspend = 0;
+ }
+
+ tx = MAX3100_RD;
+ /* rx a char so we get MAX3100_T and CTS current */
+ rxchars += max3100_sr(s, tx, &rx, 0);
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ nchars = s->tx_buf_tot - s->tx_buf_cur;
+ tx = MAX3100_WD | (s->rts ? MAX3100_RTS : 0);
+ tx |= s->tx_buf[s->tx_buf_cur];
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+
+ if ((rx & MAX3100_T) && /* tx buffer empty*/
+ max3100_ok_to_send(s) && /* fw ctrl decision */
+ nchars > 0 && /* more to send */
+ !s->force_end_work) {
+ if (s->parity & MAX3100_PARITY_ON)
+ max3100_calc_parity(s, &tx);
+ rxchars += max3100_sr(s, tx, &rx, 0);
+ nchars -= 1;
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ s->tx_buf_cur += 1;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ if (nchars == 0) {
+ tty_wakeup(s->tty);
+ wake_up(&s->all_sent);
+ }
+ }
+ if (rxchars > MAX3100_FLIP_EVERY) {
+ tty_schedule_flip(s->tty);
+ rxchars = 0;
+ }
+ }
+ while ((nchars > 0 || /* more to send */
+ rx & MAX3100_R) && /* try to empy all the RX buffer */
+ !s->force_end_work);
+ if (rxchars)
+ tty_schedule_flip(s->tty);
+ /* reschedule ourself if we have more chars to send (can be
+ * that TX buffer was full). Must do this since we cannot
+ * use TX empty interrupt. */
+ if (s->tx_buf_tot > 0 && s->tx_buf_cur < s->tx_buf_tot)
+ max3100_dowork(s);
+ if (!s->only_edge_irq && !s->force_end_work)
+ irq_state(s, 1);
+}
+
+static irqreturn_t max3100_irq(int irqno, void *dev_id)
+{
+ struct max3100_port_s *s = dev_id;
+
+ if (!s->only_edge_irq)
+ irq_state(s, 0); /* avoid irq storm */
+ max3100_dowork(s);
+ return IRQ_HANDLED;
+}
+
+static void rs_stop(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ s->tx_stopped = 1;
+}
+
+static void rs_start(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ s->tx_stopped = 0;
+}
+
+static void rs_flush_chars(struct tty_struct *tty)
+{
+}
+
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ wait_event_timeout(s->all_sent,
+ s->tx_buf_tot == 0 || s->tx_buf_tot == s->tx_buf_cur,
+ timeout);
+}
+
+static void rs_flush_buffer(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = 0;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+}
+
+static int rs_write(struct tty_struct *tty,
+ const unsigned char *buf, int count)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_tot > 0 && s->tx_buf_cur < s->tx_buf_tot) {
+ count = 0;
+ } else {
+ if (count > MAX3100_TX_BUF_N)
+ count = MAX3100_TX_BUF_N;
+ memcpy(s->tx_buf, buf, count);
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = count;
+ }
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ max3100_dowork(s);
+ return count;
+}
+
+static int rs_write_room(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_tot > 0 && s->tx_buf_cur < s->tx_buf_tot)
+ ret = 0;
+ else
+ ret = MAX3100_TX_BUF_N;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ return ret;
+}
+
+static int rs_chars_in_buffer(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->tx_buf_lock, flags);
+ if (s->tx_buf_tot > 0 && s->tx_buf_cur < s->tx_buf_tot)
+ ret = MAX3100_TX_BUF_N;
+ else
+ ret = 0;
+ spin_unlock_irqrestore(&s->tx_buf_lock, flags);
+ return ret;
+}
+
+static void internal_throttle(struct tty_struct *tty, char ch, int rts)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ u16 tx = 0, rx;
+ int old_tx_stopped;
+
+ old_tx_stopped = s->tx_stopped;
+ s->tx_stopped = 1;
+ tx = MAX3100_RD;
+ /* wait for tx buf empty. Unfortunately we cannot avoid a busy
+ loop (it should not take much since we block tx ... so at
+ most a byte time) since TX empty interrupt is unusable (see
+ Notes on top) */
+ do {
+ max3100_sr(s, tx, &rx, 1);
+ if ((rx & MAX3100_T) == 0)
+ schedule();
+ } while ((rx & MAX3100_T) == 0);
+
+ if (I_IXOFF(tty))
+ tx = MAX3100_WD | (s->rts ? MAX3100_RTS : 0) | (ch&0xff);
+ if (C_CRTSCTS(tty)) {
+ s->rts = rts ? 1 : 0;
+ tx = MAX3100_WD | (s->rts ? MAX3100_RTS : 0) | MAX3100_TE;
+ }
+ if (tx)
+ max3100_sr(s, tx, &rx, 1);
+ s->tx_stopped = old_tx_stopped;
+ max3100_dowork(s);
+}
+
+static void rs_throttle(struct tty_struct *tty)
+{
+ internal_throttle(tty, STOP_CHAR(tty), 0);
+}
+
+static void rs_unthrottle(struct tty_struct *tty)
+{
+ internal_throttle(tty, START_CHAR(tty), 1);
+}
+
+static int get_lsr_info(struct max3100_port_s *s, unsigned int *value)
+{
+ unsigned char status;
+ u16 tx = 0, rx;
+
+ tx = MAX3100_RD;
+ max3100_sr(s, tx, &rx, 1);
+ status = (rx & MAX3100_CTS) > 0;
+ return put_user(status, value);
+}
+
+static int rs_ioctl(struct tty_struct *tty, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int retval = 0;
+
+ switch (cmd) {
+
+ case TIOCSERGETLSR: /* Get line status register */
+ return get_lsr_info(s, (unsigned int *) arg);
+
+ default:
+ retval = -ENOIOCTLCMD ;
+ }
+ return retval;
+}
+
+static void change_speed(struct max3100_port_s *s)
+{
+ unsigned cflag;
+ unsigned i;
+ u32 param_new;
+ u32 param_mask;
+
+ cflag = s->tty->termios->c_cflag;
+ param_new = 0;
+ param_mask = 0;
+
+ i = cflag & CBAUD;
+ switch (i) {
+ case B300:
+ if (s->crystal) {
+ param_new = 16;
+ } else {
+ dev_warn(&s->spi->dev, "unsupported baud rate!\n");
+ param_new = 15;
+ }
+ break;
+ case B600:
+ param_new = 15;
+ break;
+ case B1200:
+ param_new = 14;
+ break;
+ case B2400:
+ param_new = 13;
+ break;
+ case B4800:
+ param_new = 12;
+ break;
+ case B9600:
+ param_new = 11;
+ break;
+ case B19200:
+ param_new = 10;
+ break;
+ case B38400:
+ param_new = 9;
+ break;
+ case B57600:
+ param_new = 2;
+ break;
+ case B115200:
+ param_new = 1;
+ break;
+ case B230400:
+ if (s->crystal) {
+ param_new = 1;
+ dev_warn(&s->spi->dev, "unsupported baud rate!\n");
+ } else {
+ param_new = 0;
+ }
+ break;
+ default:
+ param_new = 1;
+ dev_warn(&s->spi->dev, "invalid baudrate\n");
+ }
+ param_new = (param_new - s->crystal) & MAX3100_BAUD;
+ param_mask |= MAX3100_BAUD;
+
+ if ((cflag & CSIZE) == CS8) {
+ param_new &= ~MAX3100_L;
+ s->parity &= ~MAX3100_7BIT;
+ } else {
+ param_new |= MAX3100_L;
+ s->parity |= MAX3100_7BIT;
+ }
+ param_mask |= MAX3100_L;
+
+ if (cflag & CSTOPB)
+ param_new |= MAX3100_ST;
+ else
+ param_new &= ~MAX3100_ST;
+ param_mask |= MAX3100_ST;
+
+ if (cflag & PARENB) {
+ param_new |= MAX3100_PE;
+ s->parity |= MAX3100_PARITY_ON;
+ } else {
+ param_new &= ~MAX3100_PE;
+ s->parity &= ~MAX3100_PARITY_ON;
+ }
+ param_mask |= MAX3100_PE;
+
+ if (cflag & PARODD) {
+ s->parity |= MAX3100_PARITY_ODD;
+ } else {
+ s->parity &= ~MAX3100_PARITY_ODD;
+ }
+
+ s->conf = (s->conf & ~param_mask) | (param_new & param_mask);
+ max3100_send_conf(s);
+
+ return;
+}
+
+
+static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ if (tty->termios->c_cflag == old_termios->c_cflag)
+ return;
+
+ change_speed(s);
+
+ if ((old_termios->c_cflag & CRTSCTS) &&
+ !(tty->termios->c_cflag & CRTSCTS))
+ max3100_dowork(s);
+}
+
+static void shutdown(struct max3100_port_s *s)
+{
+ u16 tx, rx;
+
+ s->force_end_work = 1;
+ if (s->workqueue) {
+ flush_workqueue(s->workqueue);
+ destroy_workqueue(s->workqueue);
+ }
+ if (s->irq)
+ free_irq(s->irq, s);
+ kfree(s->tx_buf);
+ s->tx_buf = NULL;
+ if (s->tty)
+ set_bit(TTY_IO_ERROR, &s->tty->flags);
+ /* set shutdown mode to save power */
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(s, tx, &rx, 0);
+}
+
+static void rs_hangup(struct tty_struct *tty)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ shutdown(s);
+}
+
+static int startup(struct max3100_port_s *s)
+{
+ char b[10];
+ int irq_type;
+
+ s->tx_buf = kmalloc(MAX3100_TX_BUF_N, GFP_KERNEL);
+ if (s->tx_buf == NULL)
+ return -ENOMEM;
+ s->tx_buf_cur = 0;
+ s->tx_buf_tot = 0;
+
+ s->force_end_work = 0;
+ s->parity = 0;
+ s->rts = 0;
+ s->tx_stopped = 0;
+ s->conf = MAX3100_RM;
+
+ sprintf(b, "max3100-%d", s->minor);
+ s->workqueue = create_singlethread_workqueue(b);
+ if (!s->workqueue) {
+ dev_warn(&s->spi->dev, "cannot create workqueue\n");
+ return -EBUSY;
+ }
+ INIT_WORK(&s->work, max3100_work);
+
+ s->irq_status = 1; /* IRQS are on after request */
+ if (s->only_edge_irq)
+ irq_type = IRQF_TRIGGER_FALLING;
+ else
+ irq_type = IRQF_TRIGGER_LOW;
+ if (request_irq(s->irq, max3100_irq, irq_type, "max3100", s) < 0) {
+ dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
+ s->irq = 0;
+ kfree(s->tx_buf);
+ return -EBUSY;
+ }
+
+ if (s->tty)
+ clear_bit(TTY_IO_ERROR, &s->tty->flags);
+
+ change_speed(s);
+ mdelay(50); /* waits for wakeup from shutdown */
+
+ if (s->loopback) {
+ u16 tx, rx;
+ tx = 0x4001;
+ max3100_sr(s, tx, &rx, 1);
+ }
+
+ return 0;
+}
+
+int rs_open(struct tty_struct *tty, struct file *filp)
+{
+ struct max3100_port_s *s;
+ int retval = 0, line;
+
+ line = tty->index;
+
+ if (line >= MAX_MAX3100 || line < 0)
+ return -ENODEV;
+
+ s = max3100s[line];
+
+ if (!s) {
+ printk(KERN_ERR "Nonexistent max3100 for index %d\n", line);
+ return -ENODEV;
+ }
+
+ retval = mutex_lock_interruptible(&s->sem);
+ if (retval < 0)
+ return retval;
+
+ s->ref_count++;
+
+ if (s->ref_count == 1) {
+ tty->driver_data = s;
+ s->tty = tty;
+
+ retval = startup(s);
+ }
+
+ mutex_unlock(&s->sem);
+
+ return retval;
+}
+
+static void rs_close(struct tty_struct *tty, struct file *filp)
+{
+ struct max3100_port_s *s = tty->driver_data;
+
+ mutex_lock(&s->sem);
+
+ s->ref_count--;
+ if (s->ref_count == 0)
+ shutdown(s);
+
+ mutex_unlock(&s->sem);
+}
+
+static int rs_tiocmget(struct tty_struct *tty, struct file *file)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ u16 tx, rx;
+ unsigned int result;
+
+ tx = MAX3100_RD;
+ max3100_sr(s, tx, &rx, 1);
+
+ result = ((s->rts) ? TIOCM_RTS : 0)
+ | ((rx & MAX3100_CTS) ? TIOCM_CTS : 0);
+ return result;
+}
+
+static int rs_tiocmset(struct tty_struct *tty, struct file *file,
+ unsigned int set, unsigned int clear)
+{
+ struct max3100_port_s *s = tty->driver_data;
+ int old_rts = s->rts;
+ u16 tx, rx;
+
+ if (set & TIOCM_RTS)
+ s->rts = 1;
+ if (clear & TIOCM_RTS)
+ s->rts = 0;
+
+ if (s->rts != old_rts) {
+ tx = MAX3100_WD | (s->rts ? MAX3100_RTS : 0) | MAX3100_TE;
+ max3100_sr(s, tx, &rx, 1);
+ }
+ return 0;
+}
+
+static struct tty_operations rs_ops = {
+ .open = rs_open,
+ .close = rs_close,
+ .write = rs_write,
+ .flush_chars = rs_flush_chars,
+ .wait_until_sent = rs_wait_until_sent,
+ .write_room = rs_write_room,
+ .chars_in_buffer = rs_chars_in_buffer,
+ .flush_buffer = rs_flush_buffer,
+ .ioctl = rs_ioctl,
+ .throttle = rs_throttle,
+ .unthrottle = rs_unthrottle,
+ .set_termios = rs_set_termios,
+ .stop = rs_stop,
+ .start = rs_start,
+ .hangup = rs_hangup,
+ .tiocmget = rs_tiocmget,
+ .tiocmset = rs_tiocmset,
+};
+
+static int __devinit max3100_probe(struct spi_device *spi)
+{
+ int i;
+ struct plat_max3100 *pdata;
+ u16 tx, rx;
+
+ if (!serial_driver) {
+ serial_driver = alloc_tty_driver(MAX_MAX3100);
+ if (!serial_driver) {
+ printk(KERN_ERR "Cannot allocate serial driver\n");
+ return -ENOMEM;
+ }
+
+ serial_driver->name = "ttyMAX";
+ serial_driver->driver_name = "ttyMAX";
+ serial_driver->major = TTY_MAJOR;
+ /* this should prevent clashes */
+ serial_driver->minor_start = 128;
+ serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ serial_driver->subtype = SERIAL_TYPE_NORMAL;
+ serial_driver->init_termios = tty_std_termios;
+ serial_driver->init_termios.c_cflag =
+ B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ serial_driver->flags = TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_DEV;
+ tty_set_operations(serial_driver, &rs_ops);
+
+ if (tty_register_driver(serial_driver)) {
+ put_tty_driver(serial_driver);
+ printk(KERN_ERR "Couldn't register serial driver\n");
+ return -EINVAL;
+ }
+ }
+
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (!max3100s[i])
+ break;
+ if (i == MAX_MAX3100) {
+ dev_warn(&spi->dev, "too many MAX3100 chips\n");
+ return -ENOMEM;
+ }
+
+ max3100s[i] = kzalloc(sizeof(struct max3100_port_s), GFP_KERNEL);
+ if (!max3100s[i]) {
+ dev_warn(&spi->dev,
+ "kmalloc for max3100 structure %d failed!\n", i);
+ return -ENOMEM;
+ }
+ max3100s[i]->spi = spi;
+ max3100s[i]->irq = spi->irq;
+ mutex_init(&max3100s[i]->sem);
+ mutex_init(&max3100s[i]->spi_txrx);
+ spin_lock_init(&max3100s[i]->tx_buf_lock);
+ spin_lock_init(&max3100s[i]->irq_lock);
+ init_waitqueue_head(&max3100s[i]->all_sent);
+ dev_set_drvdata(&spi->dev, max3100s[i]);
+ pdata = spi->dev.platform_data;
+ max3100s[i]->crystal = pdata->crystal;
+ max3100s[i]->loopback = pdata->loopback;
+ max3100s[i]->only_edge_irq = pdata->only_edge_irq;
+ max3100s[i]->after_suspend = 0;
+ max3100s[i]->max3100_hw_suspend = pdata->max3100_hw_suspend;
+ max3100s[i]->minor = i;
+ tty_register_device(serial_driver, i, &spi->dev);
+ /* set shutdown mode to save power. Will be woken-up on open */
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(max3100s[i], tx, &rx, 0);
+
+ return 0;
+}
+
+static int __devexit max3100_remove(struct spi_device *spi)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+ int i;
+
+ if (s->ref_count > 0)
+ return -EBUSY;
+
+ /* find out the index for the chip we are removing */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i] == s)
+ break;
+
+ tty_unregister_device(serial_driver, i);
+ kfree(max3100s[i]);
+ max3100s[i] = NULL;
+
+ /* check if this is the last chip we have */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i])
+ return 0;
+ tty_unregister_driver(serial_driver);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int max3100_suspend(struct spi_device *spi, pm_message_t state)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+
+ s->force_end_work = 1;
+ irq_state(s, 0);
+ synchronize_irq(s->irq);
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(1);
+ else {
+ /* no HW suspend, so do SW one */
+ u16 tx, rx;
+
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(s, tx, &rx, 0);
+ }
+ return 0;
+}
+
+static int max3100_resume(struct spi_device *spi)
+{
+ struct max3100_port_s *s = dev_get_drvdata(&spi->dev);
+
+ s->force_end_work = 0;
+ irq_state(s, 1);
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(0);
+ s->after_suspend = 1;
+ max3100_dowork(s);
+ return 0;
+}
+
+#else
+#define max3100_suspend NULL
+#define max3100_resume NULL
+#endif
+
+static struct spi_driver max3100_driver = {
+ .driver = {
+ .name = "max3100",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+
+ .probe = max3100_probe,
+ .remove = __devexit_p(max3100_remove),
+ .suspend = max3100_suspend,
+ .resume = max3100_resume,
+};
+
+
+static int __init max3100_init(void)
+{
+ return spi_register_driver(&max3100_driver);
+}
+module_init(max3100_init);
+
+static void __exit max3100_exit(void)
+{
+ spi_unregister_driver(&max3100_driver);
+}
+module_exit(max3100_exit);
+
+MODULE_DESCRIPTION("MAX3100 driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/serial_max3100.h b/include/linux/serial_max3100.h
new file mode 100644
index 0000000..5c0489e
--- /dev/null
+++ b/include/linux/serial_max3100.h
@@ -0,0 +1,28 @@
+
+/*
+ *
+ * Copyright (C) 2007 Christian Pellegrin
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+
+#ifndef _LINUX_SERIAL_MAX3100_H
+#define _LINUX_SERIAL_MAX3100_H 1
+
+struct plat_max3100 {
+/* force MAX3100 in loopback */
+ int loopback;
+/* 0 for 3.6864 Mhz, 1 for 1.8432 */
+ int crystal;
+/* for archs like PXA with only edge irqs */
+ int only_edge_irq;
+/* MAX3100 has a shutdown pin. This is a hook
+ called on suspend and resume to activate it.*/
+ void (*max3100_hw_suspend) (int suspend);
+};
+
+#endif
--
1.4.4.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH RESEND] max3100 driver
@ 2008-09-20 12:57 Christian Pellegrin
0 siblings, 0 replies; 5+ messages in thread
From: Christian Pellegrin @ 2008-09-20 12:57 UTC (permalink / raw)
To: linux-kernel
Cc: linux-serial, spi-devel-general, alan, akpm, Christian Pellegrin
This patch adds support for the MAX3100 SPI UART.
Generated on 20080920 against v2.6.27-rc6
Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
---
Documentation/devices.txt | 3 +
drivers/serial/Kconfig | 6 +-
drivers/serial/Makefile | 1 +
drivers/serial/max3100.c | 953 ++++++++++++++++++++++++++++++++++++++++
include/linux/serial_core.h | 3 +
include/linux/serial_max3100.h | 31 ++
6 files changed, 996 insertions(+), 1 deletions(-)
diff --git a/Documentation/devices.txt b/Documentation/devices.txt
index 05c8064..c228887 100644
--- a/Documentation/devices.txt
+++ b/Documentation/devices.txt
@@ -2807,6 +2807,9 @@ Your cooperation is appreciated.
...
190 = /dev/ttyUL3 Xilinx uartlite - port 3
191 = /dev/xvc0 Xen virtual console - port 0
+ 192 = /dev/ttyMAX0 first MAX3100 UART
+ ...
+ 195 = /dev/ttyMAX3 fourth MAX3100 UART
205 char Low-density serial ports (alternate device)
0 = /dev/culu0 Callout device for ttyLU0
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 77cb342..de3193d 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -509,7 +509,11 @@ config SERIAL_S3C2440
help
Serial port support for the Samsung S3C2440 and S3C2442 SoC
-
+config SERIAL_MAX3100
+ tristate "MAX3100 support"
+ depends on SPI
+ help
+ MAX3100 chip support
config SERIAL_DZ
bool "DECstation DZ serial driver"
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 7e7383e..21c3daf 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_SERIAL_S3C2400) += s3c2400.o
obj-$(CONFIG_SERIAL_S3C2410) += s3c2410.o
obj-$(CONFIG_SERIAL_S3C2412) += s3c2412.o
obj-$(CONFIG_SERIAL_S3C2440) += s3c2440.o
+obj-$(CONFIG_SERIAL_MAX3100) += max3100.o
obj-$(CONFIG_SERIAL_SUNCORE) += suncore.o
obj-$(CONFIG_SERIAL_SUNHV) += sunhv.o
obj-$(CONFIG_SERIAL_SUNZILOG) += sunzilog.o
diff --git a/drivers/serial/max3100.c b/drivers/serial/max3100.c
new file mode 100644
index 0000000..12889b3
--- /dev/null
+++ b/drivers/serial/max3100.c
@@ -0,0 +1,953 @@
+/*
+ *
+ * Copyright (C) 2008 Christian Pellegrin <chripell@evolware.org>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ *
+ * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have
+ * to use polling for flow control. TX empty IRQ is unusable, since
+ * writing conf clears FIFO buffer and we cannot have this interrupt
+ * always asking us for attention.
+ *
+ * Example platform data:
+
+static struct plat_max3100 max3100_plat_data = {
+ .loopback = 0,
+ .crystal = 0,
+ .only_edge_irq = 0,
+ .poll_time = 100,
+};
+
+static struct spi_board_info spi_board_info[] = {
+ {
+ .modalias = "max3100",
+ .platform_data = &max3100_plat_data,
+ .irq = IRQ_EINT12,
+ .max_speed_hz = 5*1000*1000,
+ .chip_select = 0,
+ },
+};
+
+ * The initial minor number is 192 in the low-density serial port:
+ * mknod /dev/ttyMAX0 c 204 192
+ */
+
+#define MAX3100_MAJOR 204
+#define MAX3100_MINOR 192
+/* 4 MAX3100s should be enough for everyone */
+#define MAX_MAX3100 4
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/spi/spi.h>
+#include <linux/freezer.h>
+
+#include <linux/serial_max3100.h>
+
+#define MAX3100_C (1<<14)
+#define MAX3100_D (0<<14)
+#define MAX3100_W (1<<15)
+#define MAX3100_RX (0<<15)
+
+#define MAX3100_WC (MAX3100_W | MAX3100_C)
+#define MAX3100_RC (MAX3100_RX | MAX3100_C)
+#define MAX3100_WD (MAX3100_W | MAX3100_D)
+#define MAX3100_RD (MAX3100_RX | MAX3100_D)
+#define MAX3100_CMD (3 << 14)
+
+#define MAX3100_T (1<<14)
+#define MAX3100_R (1<<15)
+
+#define MAX3100_FEN (1<<13)
+#define MAX3100_SHDN (1<<12)
+#define MAX3100_TM (1<<11)
+#define MAX3100_RM (1<<10)
+#define MAX3100_PM (1<<9)
+#define MAX3100_RAM (1<<8)
+#define MAX3100_IR (1<<7)
+#define MAX3100_ST (1<<6)
+#define MAX3100_PE (1<<5)
+#define MAX3100_L (1<<4)
+#define MAX3100_BAUD (0xf)
+
+#define MAX3100_TE (1<<10)
+#define MAX3100_RAFE (1<<10)
+#define MAX3100_RTS (1<<9)
+#define MAX3100_CTS (1<<9)
+#define MAX3100_PT (1<<8)
+#define MAX3100_DATA (0xff)
+
+#define MAX3100_RT (MAX3100_R | MAX3100_T)
+#define MAX3100_RTC (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)
+
+/* the following simulate a status reg for ignore_status_mask */
+#define MAX3100_STATUS_PE 1
+#define MAX3100_STATUS_FE 2
+#define MAX3100_STATUS_OE 4
+
+struct max3100_port {
+ struct uart_port port;
+ struct spi_device *spi;
+
+ int cts; /* last CTS received for flow ctrl */
+ int tx_empty; /* last TX empty bit */
+
+ spinlock_t conf_lock; /* shared data */
+ int conf_commit; /* need to make changes */
+ int conf; /* configuration for the MAX31000
+ * (bits 0-7, bits 8-11 are irqs) */
+ int rts_commit; /* need to change rts */
+ int rts; /* rts status */
+
+ int parity; /* keeps track if we should send parity */
+#define MAX3100_PARITY_ON 1
+#define MAX3100_PARITY_ODD 2
+#define MAX3100_7BIT 4
+ int rx_enabled; /* if we should rx chars */
+
+ int irq; /* irq assigned to the max3100 */
+
+ int minor; /* minor number */
+ int crystal; /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
+ int loopback; /* 1 if we are in loopback mode */
+ int only_edge_irq; /* 1 if we have only edge irqs (like PXA) */
+
+ /* for handling irqs: need workqueue since we do spi_sync */
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+ /* set to 1 to make the workhandler exit as soon as possible */
+ int force_end_work;
+ /* need to know we are suspending to avoid deadlock on workqueue */
+ int suspending;
+
+ /* these are for IRQ on/off counting */
+ int irq_status;
+ /* avoid race condition on irq_status */
+ spinlock_t irq_lock;
+
+ /* hook for suspending MAX3100 via dedicated pin */
+ void (*max3100_hw_suspend) (int suspend);
+
+ /* poll time (in ms) for ctrl lines */
+ int poll_time;
+ /* and its timer */
+ struct timer_list timer;
+};
+
+static struct max3100_port *max3100s[MAX_MAX3100]; /* the chips */
+
+static void irq_state(struct max3100_port *s, int on)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->irq_lock, flags);
+ if (s->irq_status != on) {
+ if (on)
+ enable_irq(s->irq);
+ else
+ disable_irq(s->irq);
+ s->irq_status = on;
+ }
+ spin_unlock_irqrestore(&s->irq_lock, flags);
+}
+
+static int max3100_do_parity(struct max3100_port *s, u16 c)
+{
+ int parity;
+
+ if (s->parity & MAX3100_PARITY_ODD)
+ parity = 1;
+ else
+ parity = 0;
+
+ if (s->parity & MAX3100_7BIT)
+ c &= 0x7f;
+ else
+ c &= 0xff;
+
+ parity = parity ^ (hweight8(c) & 1);
+ return parity;
+}
+
+static int max3100_check_parity(struct max3100_port *s, u16 c)
+{
+ return max3100_do_parity(s, c) == ((c >> 8) & 1);
+}
+
+static void max3100_calc_parity(struct max3100_port *s, u16 *c)
+{
+ if (s->parity & MAX3100_7BIT)
+ *c &= 0x7f;
+ else
+ *c &= 0xff;
+
+ if (s->parity & MAX3100_PARITY_ON)
+ *c |= max3100_do_parity(s, *c) << 8;
+}
+
+static void max3100_work(struct work_struct *w);
+
+static void max3100_dowork(struct max3100_port *s)
+{
+ if (!s->force_end_work && !work_pending(&s->work))
+ queue_work(s->workqueue, &s->work);
+}
+
+static void max3100_timeout(unsigned long data)
+{
+ struct max3100_port *s = (struct max3100_port *)data;
+
+ if (s->port.info) {
+ max3100_dowork(s);
+ mod_timer(&s->timer, jiffies + s->poll_time);
+ }
+}
+
+static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx)
+{
+ struct spi_message message;
+ u16 etx, erx;
+ int status;
+ struct spi_transfer tran = {
+ .tx_buf = &etx,
+ .rx_buf = &erx,
+ .len = 2,
+ };
+
+
+ etx = htons(tx);
+ spi_message_init(&message);
+ spi_message_add_tail(&tran, &message);
+ status = spi_sync(s->spi, &message);
+ if (status) {
+ dev_warn(&s->spi->dev, "error while calling spi_sync\n");
+ return -EIO;
+ }
+ *rx = ntohs(erx);
+ s->tx_empty = (*rx & MAX3100_T) > 0;
+ dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);
+ return 0;
+}
+
+static int max3100_handlerx(struct max3100_port *s, u16 rx)
+{
+ unsigned int ch, flg, status = 0;
+ int ret = 0, cts;
+
+ if (rx & MAX3100_R && s->rx_enabled) {
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+ ch = rx & (s->parity & MAX3100_7BIT ? 0x7f : 0xff);
+ if (rx & MAX3100_RAFE) {
+ s->port.icount.frame++;
+ flg = TTY_FRAME;
+ status |= MAX3100_STATUS_FE;
+ } else {
+ if (s->parity & MAX3100_PARITY_ON) {
+ if (max3100_check_parity(s, rx)) {
+ s->port.icount.rx++;
+ flg = TTY_NORMAL;
+ } else {
+ s->port.icount.parity++;
+ flg = TTY_PARITY;
+ status |= MAX3100_STATUS_PE;
+ }
+ } else {
+ s->port.icount.rx++;
+ flg = TTY_NORMAL;
+ }
+ }
+ uart_insert_char(&s->port, status, MAX3100_STATUS_OE, ch, flg);
+ ret = 1;
+ }
+
+ cts = (rx & MAX3100_CTS) > 0;
+ if (s->cts != cts) {
+ s->cts = cts;
+ uart_handle_cts_change(&s->port, cts ? TIOCM_CTS : 0);
+ }
+
+ return ret;
+}
+
+static void max3100_work(struct work_struct *w)
+{
+ struct max3100_port *s = container_of(w, struct max3100_port, work);
+ int rxchars;
+ u16 tx, rx;
+ int conf, cconf, rts, crts;
+ struct circ_buf *xmit = &s->port.info->xmit;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ do {
+ rxchars = 0;
+
+ spin_lock(&s->conf_lock);
+ conf = s->conf;
+ cconf = s->conf_commit;
+ s->conf_commit = 0;
+ rts = s->rts;
+ crts = s->rts_commit;
+ s->rts_commit = 0;
+ spin_unlock(&s->conf_lock);
+ if (cconf)
+ max3100_sr(s, MAX3100_WC | conf, &rx);
+ if (crts) {
+ max3100_sr(s, MAX3100_WD | MAX3100_TE |
+ (s->rts ? MAX3100_RTS : 0), &rx);
+ rxchars += max3100_handlerx(s, rx);
+ }
+
+ max3100_sr(s, MAX3100_RD, &rx);
+ rxchars += max3100_handlerx(s, rx);
+
+ if (rx & MAX3100_T) {
+ tx = 0xffff;
+ if (s->port.x_char) {
+ tx = s->port.x_char;
+ s->port.icount.tx++;
+ s->port.x_char = 0;
+ } else if (!uart_circ_empty(xmit) &&
+ !uart_tx_stopped(&s->port)) {
+ tx = xmit->buf[xmit->tail];
+ xmit->tail = (xmit->tail + 1) &
+ (UART_XMIT_SIZE - 1);
+ s->port.icount.tx++;
+ }
+ if (tx != 0xffff) {
+ max3100_calc_parity(s, &tx);
+ tx |= MAX3100_WD | (s->rts ? MAX3100_RTS : 0);
+ max3100_sr(s, tx, &rx);
+ rxchars += max3100_handlerx(s, rx);
+ }
+ }
+
+ if (rxchars > 0)
+ tty_flip_buffer_push(s->port.info->port.tty);
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&s->port);
+
+ } while (!s->force_end_work &&
+ !freezing(current) &&
+ ((rx & MAX3100_R) ||
+ (!uart_circ_empty(xmit) &&
+ !uart_tx_stopped(&s->port))));
+
+ if (!s->only_edge_irq && !s->force_end_work &&
+ !freezing(current))
+ irq_state(s, 1);
+}
+
+static irqreturn_t max3100_irq(int irqno, void *dev_id)
+{
+ struct max3100_port *s = dev_id;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ if (!s->only_edge_irq)
+ irq_state(s, 0); /* avoid irq storm */
+ max3100_dowork(s);
+ return IRQ_HANDLED;
+}
+
+static void max3100_enable_ms(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ if (s->poll_time > 0)
+ mod_timer(&s->timer, jiffies);
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+}
+
+static void max3100_start_tx(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ max3100_dowork(s);
+}
+
+static void max3100_stop_rx(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ s->rx_enabled = 0;
+ spin_lock(&s->conf_lock);
+ s->conf &= ~MAX3100_RM;
+ s->conf_commit = 1;
+ spin_unlock(&s->conf_lock);
+ max3100_dowork(s);
+}
+
+static unsigned int max3100_tx_empty(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ /* may not be truly up-to-date */
+ max3100_dowork(s);
+ return s->tx_empty;
+}
+
+static unsigned int max3100_get_mctrl(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ /* may not be truly up-to-date */
+ max3100_dowork(s);
+ /* always assert DCD and DSR since these lines are not wired */
+ return (s->cts ? TIOCM_CTS : 0) | TIOCM_DSR | TIOCM_CAR;
+}
+
+static void max3100_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+ int rts;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ rts = (mctrl & TIOCM_RTS) > 0;
+
+ spin_lock(&s->conf_lock);
+ if (s->rts != rts) {
+ s->rts = rts;
+ s->rts_commit = 1;
+ max3100_dowork(s);
+ }
+ spin_unlock(&s->conf_lock);
+}
+
+static void
+max3100_set_termios(struct uart_port *port, struct ktermios *termios,
+ struct ktermios *old)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+ int baud = 0;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ if (!old || (termios->c_cflag != old->c_cflag)) {
+ unsigned cflag;
+ unsigned i;
+ u32 param_new;
+ u32 param_mask;
+ u32 parity = 0;
+
+ cflag = termios->c_cflag;
+ param_new = 0;
+ param_mask = 0;
+
+ i = cflag & CBAUD;
+ switch (i) {
+ case B300:
+ if (s->crystal) {
+ param_new = 16;
+ } else {
+ dev_warn(&s->spi->dev,
+ "unsupported baud rate!\n");
+ param_new = 15;
+ }
+ baud = 300;
+ break;
+ case B600:
+ param_new = 15;
+ baud = 600;
+ break;
+ case B1200:
+ param_new = 14;
+ baud = 1200;
+ break;
+ case B2400:
+ param_new = 13;
+ baud = 2400;
+ break;
+ case B4800:
+ param_new = 12;
+ baud = 4800;
+ break;
+ case B9600:
+ param_new = 11;
+ baud = 9600;
+ break;
+ case B19200:
+ param_new = 10;
+ baud = 19200;
+ break;
+ case B38400:
+ param_new = 9;
+ baud = 38400;
+ break;
+ case B57600:
+ param_new = 2;
+ baud = 57600;
+ break;
+ case B115200:
+ param_new = 1;
+ baud = 11520;
+ break;
+ case B230400:
+ if (s->crystal) {
+ param_new = 1;
+ dev_warn(&s->spi->dev,
+ "unsupported baud rate!\n");
+ } else {
+ param_new = 0;
+ }
+ baud = 230400;
+ break;
+ default:
+ param_new = 1;
+ dev_warn(&s->spi->dev, "invalid baudrate\n");
+ }
+ param_new = (param_new - s->crystal) & MAX3100_BAUD;
+ param_mask |= MAX3100_BAUD;
+
+ if ((cflag & CSIZE) == CS8) {
+ param_new &= ~MAX3100_L;
+ parity &= ~MAX3100_7BIT;
+ } else {
+ param_new |= MAX3100_L;
+ parity |= MAX3100_7BIT;
+ }
+ param_mask |= MAX3100_L;
+
+ if (cflag & CSTOPB)
+ param_new |= MAX3100_ST;
+ else
+ param_new &= ~MAX3100_ST;
+ param_mask |= MAX3100_ST;
+
+ if (cflag & PARENB) {
+ param_new |= MAX3100_PE;
+ parity |= MAX3100_PARITY_ON;
+ } else {
+ param_new &= ~MAX3100_PE;
+ parity &= ~MAX3100_PARITY_ON;
+ }
+ param_mask |= MAX3100_PE;
+
+ if (cflag & PARODD)
+ parity |= MAX3100_PARITY_ODD;
+ else
+ parity &= ~MAX3100_PARITY_ODD;
+
+ s->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ s->port.ignore_status_mask |=
+ MAX3100_STATUS_PE | MAX3100_STATUS_FE |
+ MAX3100_STATUS_OE;
+
+ if (s->poll_time > 0)
+ del_timer_sync(&s->timer);
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ spin_lock(&s->conf_lock);
+ s->conf = (s->conf & ~param_mask) | (param_new & param_mask);
+ s->conf_commit = 1;
+ s->parity = parity;
+ spin_unlock(&s->conf_lock);
+ max3100_dowork(s);
+
+ if (UART_ENABLE_MS(&s->port, termios->c_cflag))
+ max3100_enable_ms(&s->port);
+ }
+}
+
+static void max3100_shutdown(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ if (s->suspending)
+ return;
+
+ s->force_end_work = 1;
+
+ if (s->poll_time > 0)
+ del_timer_sync(&s->timer);
+
+ if (s->workqueue) {
+ flush_workqueue(s->workqueue);
+ destroy_workqueue(s->workqueue);
+ }
+ if (s->irq)
+ free_irq(s->irq, s);
+
+ /* set shutdown mode to save power */
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(1);
+ else {
+ u16 tx, rx;
+
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(s, tx, &rx);
+ }
+}
+
+static int max3100_startup(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+ char b[12];
+ int irq_type;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ s->conf = MAX3100_RM;
+ s->rx_enabled = 1;
+
+ if (s->suspending)
+ return 0;
+
+ s->force_end_work = 0;
+ s->parity = 0;
+ s->rts = 0;
+
+ sprintf(b, "max3100-%d", s->minor);
+ s->workqueue = create_freezeable_workqueue(b);
+ if (!s->workqueue) {
+ dev_warn(&s->spi->dev, "cannot create workqueue\n");
+ return -EBUSY;
+ }
+ INIT_WORK(&s->work, max3100_work);
+
+ s->irq_status = 1; /* IRQS are on after request */
+ if (s->only_edge_irq)
+ irq_type = IRQF_TRIGGER_FALLING;
+ else
+ irq_type = IRQF_TRIGGER_LOW;
+ if (request_irq(s->irq, max3100_irq, irq_type, "max3100", s) < 0) {
+ dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
+ s->irq = 0;
+ destroy_workqueue(s->workqueue);
+ return -EBUSY;
+ }
+
+ if (s->loopback) {
+ u16 tx, rx;
+ tx = 0x4001;
+ max3100_sr(s, tx, &rx);
+ }
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(0);
+ s->conf_commit = 1;
+ max3100_dowork(s);
+ /* wait for clock to settle */
+ msleep(50);
+
+ max3100_enable_ms(&s->port);
+
+ return 0;
+}
+
+static const char *max3100_type(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ return s->port.type == PORT_MAX3100 ? "MAX3100" : NULL;
+}
+
+static void max3100_release_port(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+}
+
+static void max3100_config_port(struct uart_port *port, int flags)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ if (flags & UART_CONFIG_TYPE)
+ s->port.type = PORT_MAX3100;
+}
+
+static int max3100_verify_port(struct uart_port *port,
+ struct serial_struct *ser)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+ int ret = -EINVAL;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3100)
+ ret = 0;
+ return ret;
+}
+
+static void max3100_stop_tx(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+}
+
+static int max3100_request_port(struct uart_port *port)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+ return 0;
+}
+
+static void max3100_break_ctl(struct uart_port *port, int break_state)
+{
+ struct max3100_port *s = container_of(port,
+ struct max3100_port,
+ port);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+}
+
+static struct uart_ops max3100_ops = {
+ .tx_empty = max3100_tx_empty,
+ .set_mctrl = max3100_set_mctrl,
+ .get_mctrl = max3100_get_mctrl,
+ .stop_tx = max3100_stop_tx,
+ .start_tx = max3100_start_tx,
+ .stop_rx = max3100_stop_rx,
+ .enable_ms = max3100_enable_ms,
+ .break_ctl = max3100_break_ctl,
+ .startup = max3100_startup,
+ .shutdown = max3100_shutdown,
+ .set_termios = max3100_set_termios,
+ .type = max3100_type,
+ .release_port = max3100_release_port,
+ .request_port = max3100_request_port,
+ .config_port = max3100_config_port,
+ .verify_port = max3100_verify_port,
+};
+
+static struct uart_driver max3100_uart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "ttyMAX",
+ .dev_name = "ttyMAX",
+ .major = MAX3100_MAJOR,
+ .minor = MAX3100_MINOR,
+ .nr = MAX_MAX3100,
+};
+static int uart_driver_registered;
+
+static int __devinit max3100_probe(struct spi_device *spi)
+{
+ int i, retval;
+ struct plat_max3100 *pdata;
+ u16 tx, rx;
+
+ if (!uart_driver_registered) {
+ uart_driver_registered = 1;
+ retval = uart_register_driver(&max3100_uart_driver);
+ if (retval) {
+ printk(KERN_ERR "Couldn't register max3100 uart driver\n");
+ return retval;
+ }
+ }
+
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (!max3100s[i])
+ break;
+ if (i == MAX_MAX3100) {
+ dev_warn(&spi->dev, "too many MAX3100 chips\n");
+ return -ENOMEM;
+ }
+
+ max3100s[i] = kzalloc(sizeof(struct max3100_port), GFP_KERNEL);
+ if (!max3100s[i]) {
+ dev_warn(&spi->dev,
+ "kmalloc for max3100 structure %d failed!\n", i);
+ return -ENOMEM;
+ }
+ max3100s[i]->spi = spi;
+ max3100s[i]->irq = spi->irq;
+ spin_lock_init(&max3100s[i]->conf_lock);
+ dev_set_drvdata(&spi->dev, max3100s[i]);
+ pdata = spi->dev.platform_data;
+ max3100s[i]->crystal = pdata->crystal;
+ max3100s[i]->loopback = pdata->loopback;
+ max3100s[i]->only_edge_irq = pdata->only_edge_irq;
+ max3100s[i]->poll_time = pdata->poll_time * HZ / 1000;
+ if (pdata->poll_time > 0 && max3100s[i]->poll_time == 0)
+ max3100s[i]->poll_time = 1;
+ max3100s[i]->max3100_hw_suspend = pdata->max3100_hw_suspend;
+ max3100s[i]->minor = i;
+ init_timer(&max3100s[i]->timer);
+ max3100s[i]->timer.function = max3100_timeout;
+ max3100s[i]->timer.data = (unsigned long) max3100s[i];
+
+ dev_dbg(&spi->dev, "%s: adding port %d\n", __func__, i);
+ max3100s[i]->port.irq = max3100s[i]->irq;
+ max3100s[i]->port.uartclk = max3100s[i]->crystal ? 3686400 : 1843200;
+ max3100s[i]->port.fifosize = 16;
+ max3100s[i]->port.ops = &max3100_ops;
+ max3100s[i]->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
+ max3100s[i]->port.line = i;
+ max3100s[i]->port.type = PORT_MAX3100;
+ max3100s[i]->port.dev = &spi->dev;
+ retval = uart_add_one_port(&max3100_uart_driver, &max3100s[i]->port);
+ if (retval < 0)
+ dev_warn(&spi->dev,
+ "uart_add_one_port failed for line %d with error %d\n",
+ i, retval);
+
+ /* set shutdown mode to save power. Will be woken-up on open */
+ if (max3100s[i]->max3100_hw_suspend)
+ max3100s[i]->max3100_hw_suspend(1);
+ else {
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(max3100s[i], tx, &rx);
+ }
+ return 0;
+}
+
+static int __devexit max3100_remove(struct spi_device *spi)
+{
+ struct max3100_port *s = dev_get_drvdata(&spi->dev);
+ int i;
+
+ /* find out the index for the chip we are removing */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i] == s)
+ break;
+
+ dev_dbg(&spi->dev, "%s: removing port %d\n", __func__, i);
+ uart_remove_one_port(&max3100_uart_driver, &max3100s[i]->port);
+ kfree(max3100s[i]);
+ max3100s[i] = NULL;
+
+ /* check if this is the last chip we have */
+ for (i = 0; i < MAX_MAX3100; i++)
+ if (max3100s[i])
+ return 0;
+ pr_debug("removing max3100 driver\n");
+ uart_unregister_driver(&max3100_uart_driver);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int max3100_suspend(struct spi_device *spi, pm_message_t state)
+{
+ struct max3100_port *s = dev_get_drvdata(&spi->dev);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ s->suspending = 1;
+ uart_suspend_port(&max3100_uart_driver, &s->port);
+
+ irq_state(s, 0);
+ synchronize_irq(s->irq);
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(1);
+ else {
+ /* no HW suspend, so do SW one */
+ u16 tx, rx;
+
+ tx = MAX3100_WC | MAX3100_SHDN;
+ max3100_sr(s, tx, &rx);
+ }
+ return 0;
+}
+
+static int max3100_resume(struct spi_device *spi)
+{
+ struct max3100_port *s = dev_get_drvdata(&spi->dev);
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ irq_state(s, 1);
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(0);
+ s->conf_commit = 1;
+ max3100_dowork(s);
+
+ uart_resume_port(&max3100_uart_driver, &s->port);
+ s->suspending = 0;
+
+ return 0;
+}
+
+#else
+#define max3100_suspend NULL
+#define max3100_resume NULL
+#endif
+
+static struct spi_driver max3100_driver = {
+ .driver = {
+ .name = "max3100",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+
+ .probe = max3100_probe,
+ .remove = __devexit_p(max3100_remove),
+ .suspend = max3100_suspend,
+ .resume = max3100_resume,
+};
+
+
+static int __init max3100_init(void)
+{
+ return spi_register_driver(&max3100_driver);
+}
+module_init(max3100_init);
+
+static void __exit max3100_exit(void)
+{
+ spi_unregister_driver(&max3100_driver);
+}
+module_exit(max3100_exit);
+
+MODULE_DESCRIPTION("MAX3100 driver");
+MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 3b2f6c0..32c9fa9 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -155,6 +155,9 @@
#define PORT_SC26XX 82
+/* MAX3100 */
+#define PORT_MAX3100 83
+
#ifdef __KERNEL__
#include <linux/compiler.h>
diff --git a/include/linux/serial_max3100.h b/include/linux/serial_max3100.h
new file mode 100644
index 0000000..d1b4622
--- /dev/null
+++ b/include/linux/serial_max3100.h
@@ -0,0 +1,31 @@
+
+/*
+ *
+ * Copyright (C) 2007 Christian Pellegrin
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+
+#ifndef _LINUX_SERIAL_MAX3100_H
+#define _LINUX_SERIAL_MAX3100_H 1
+
+struct plat_max3100 {
+/* force MAX3100 in loopback */
+ int loopback;
+/* 0 for 3.6864 Mhz, 1 for 1.8432 */
+ int crystal;
+/* for archs like PXA with only edge irqs */
+ int only_edge_irq;
+/* MAX3100 has a shutdown pin. This is a hook
+ called on suspend and resume to activate it.*/
+ void (*max3100_hw_suspend) (int suspend);
+/* poll time for ctr signals in ms, 0 disables (so no hw flow
+ * ctrl is possible) */
+ int poll_time;
+};
+
+#endif
--
1.4.4.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2008-09-20 12:57 UTC | newest]
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2007-12-28 13:01 [PATCH RESEND] max3100 driver chripell
2007-12-29 1:38 ` Jan Engelhardt
2007-12-29 6:34 ` chri
2007-12-29 10:27 ` chripell
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2008-09-20 12:57 Christian Pellegrin
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