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path: root/drivers/tty/serial/max3100.c
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Diffstat (limited to 'drivers/tty/serial/max3100.c')
-rw-r--r--drivers/tty/serial/max3100.c926
1 files changed, 926 insertions, 0 deletions
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
new file mode 100644
index 00000000000..beb1afa27d8
--- /dev/null
+++ b/drivers/tty/serial/max3100.c
@@ -0,0 +1,926 @@
+/*
+ *
+ * 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,
+ .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 209 in the low-density serial port:
+ * mknod /dev/ttyMAX0 c 204 209
+ */
+
+#define MAX3100_MAJOR 204
+#define MAX3100_MINOR 209
+/* 4 MAX3100s should be enough for everyone */
+#define MAX_MAX3100 4
+
+#include <linux/delay.h>
+#include <linux/slab.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 baud; /* current baud rate */
+
+ 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 */
+
+ /* 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;
+
+ /* 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 DEFINE_MUTEX(max3100s_lock); /* race on probe */
+
+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) &&
+ !freezing(current) && !s->suspending)
+ queue_work(s->workqueue, &s->work);
+}
+
+static void max3100_timeout(unsigned long data)
+{
+ struct max3100_port *s = (struct max3100_port *)data;
+
+ if (s->port.state) {
+ 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 = cpu_to_be16(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 = be16_to_cpu(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.state->xmit;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ rxchars = 0;
+ do {
+ 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 > 16 && s->port.state->port.tty != NULL) {
+ tty_flip_buffer_push(s->port.state->port.tty);
+ rxchars = 0;
+ }
+ 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 (rxchars > 0 && s->port.state->port.tty != NULL)
+ tty_flip_buffer_push(s->port.state->port.tty);
+}
+
+static irqreturn_t max3100_irq(int irqno, void *dev_id)
+{
+ struct max3100_port *s = dev_id;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ 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;
+ unsigned cflag;
+ u32 param_new, param_mask, parity = 0;
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ cflag = termios->c_cflag;
+ param_new = 0;
+ param_mask = 0;
+
+ baud = tty_termios_baud_rate(termios);
+ param_new = s->conf & MAX3100_BAUD;
+ switch (baud) {
+ case 300:
+ if (s->crystal)
+ baud = s->baud;
+ else
+ param_new = 15;
+ break;
+ case 600:
+ param_new = 14 + s->crystal;
+ break;
+ case 1200:
+ param_new = 13 + s->crystal;
+ break;
+ case 2400:
+ param_new = 12 + s->crystal;
+ break;
+ case 4800:
+ param_new = 11 + s->crystal;
+ break;
+ case 9600:
+ param_new = 10 + s->crystal;
+ break;
+ case 19200:
+ param_new = 9 + s->crystal;
+ break;
+ case 38400:
+ param_new = 8 + s->crystal;
+ break;
+ case 57600:
+ param_new = 1 + s->crystal;
+ break;
+ case 115200:
+ param_new = 0 + s->crystal;
+ break;
+ case 230400:
+ if (s->crystal)
+ param_new = 0;
+ else
+ baud = s->baud;
+ break;
+ default:
+ baud = s->baud;
+ }
+ tty_termios_encode_baud_rate(termios, baud, baud);
+ s->baud = baud;
+ param_mask |= MAX3100_BAUD;
+
+ if ((cflag & CSIZE) == CS8) {
+ param_new &= ~MAX3100_L;
+ parity &= ~MAX3100_7BIT;
+ } else {
+ param_new |= MAX3100_L;
+ parity |= MAX3100_7BIT;
+ cflag = (cflag & ~CSIZE) | CS7;
+ }
+ 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;
+
+ /* mask termios capabilities we don't support */
+ cflag &= ~CMSPAR;
+ termios->c_cflag = cflag;
+
+ 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;
+
+ /* we are sending char from a workqueue so enable */
+ s->port.state->port.tty->low_latency = 1;
+
+ 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);
+ s->workqueue = NULL;
+ }
+ 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];
+
+ dev_dbg(&s->spi->dev, "%s\n", __func__);
+
+ s->conf = MAX3100_RM;
+ s->baud = s->crystal ? 230400 : 115200;
+ 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);
+
+ if (request_irq(s->irq, max3100_irq,
+ IRQF_TRIGGER_FALLING, "max3100", s) < 0) {
+ dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
+ s->irq = 0;
+ destroy_workqueue(s->workqueue);
+ s->workqueue = NULL;
+ 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;
+
+ mutex_lock(&max3100s_lock);
+
+ 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");
+ mutex_unlock(&max3100s_lock);
+ 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");
+ mutex_unlock(&max3100s_lock);
+ 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);
+ mutex_unlock(&max3100s_lock);
+ 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]->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);
+ }
+ mutex_unlock(&max3100s_lock);
+ return 0;
+}
+
+static int __devexit max3100_remove(struct spi_device *spi)
+{
+ struct max3100_port *s = dev_get_drvdata(&spi->dev);
+ int i;
+
+ mutex_lock(&max3100s_lock);
+
+ /* 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]) {
+ mutex_unlock(&max3100s_lock);
+ return 0;
+ }
+ pr_debug("removing max3100 driver\n");
+ uart_unregister_driver(&max3100_uart_driver);
+
+ mutex_unlock(&max3100s_lock);
+ 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__);
+
+ disable_irq(s->irq);
+
+ s->suspending = 1;
+ uart_suspend_port(&max3100_uart_driver, &s->port);
+
+ 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__);
+
+ if (s->max3100_hw_suspend)
+ s->max3100_hw_suspend(0);
+ uart_resume_port(&max3100_uart_driver, &s->port);
+ s->suspending = 0;
+
+ enable_irq(s->irq);
+
+ s->conf_commit = 1;
+ if (s->workqueue)
+ 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_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:max3100");
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 02:25:00 +0000