/*
- * max3110.c - spi uart protocol driver for Maxim 3110 on Moorestown
+ * mrst_max3110.c - spi uart protocol driver for Maxim 3110
*
- * Copyright (C) Intel 2008 Feng Tang <feng.tang@intel.com>
+ * Copyright (c) 2008-2010, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
#include <linux/irq.h>
#include <linux/init.h>
#include <linux/console.h>
-#include <linux/sysrq.h>
-#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/kthread.h>
-#include <linux/delay.h>
-#include <asm/atomic.h>
#include <linux/spi/spi.h>
-#include <linux/spi/dw_spi.h>
#include "mrst_max3110.h"
struct uart_max3110 {
struct uart_port port;
struct spi_device *spi;
- char *name;
+ char name[24];
wait_queue_head_t wq;
struct task_struct *main_thread;
u16 cur_conf;
u8 clock;
u8 parity, word_7bits;
+ u16 irq;
unsigned long uart_flags;
/* console related */
struct circ_buf con_xmit;
-
- /* irq related */
- u16 irq;
};
/* global data structure, may need be removed */
-struct uart_max3110 *pmax;
-static inline void receive_char(struct uart_max3110 *max, u8 ch);
+static struct uart_max3110 *pmax;
+
static void receive_chars(struct uart_max3110 *max,
unsigned char *str, int len);
-static int max3110_read_multi(struct uart_max3110 *max, int len, u8 *buf);
-static void max3110_console_receive(struct uart_max3110 *max);
+static int max3110_read_multi(struct uart_max3110 *max, u8 *buf);
+static void max3110_con_receive(struct uart_max3110 *max);
-int max3110_write_then_read(struct uart_max3110 *max,
- const u8 *txbuf, u8 *rxbuf, unsigned len, int always_fast)
+static int max3110_write_then_read(struct uart_max3110 *max,
+ const void *txbuf, void *rxbuf, unsigned len, int always_fast)
{
struct spi_device *spi = max->spi;
struct spi_message message;
struct spi_transfer x;
int ret;
- if (!txbuf || !rxbuf)
- return -EINVAL;
-
spi_message_init(&message);
memset(&x, 0, sizeof x);
x.len = len;
spi_message_add_tail(&x, &message);
if (always_fast)
- x.speed_hz = 3125000;
+ x.speed_hz = spi->max_speed_hz;
else if (max->baud)
x.speed_hz = max->baud;
return ret;
}
-/* Write a u16 to the device, and return one u16 read back */
-int max3110_out(struct uart_max3110 *max, const u16 out)
+/* Write a 16b word to the device */
+static int max3110_out(struct uart_max3110 *max, const u16 out)
{
- u16 tmp;
+ void *buf;
+ u16 *obuf, *ibuf;
+ u8 ch;
int ret;
- ret = max3110_write_then_read(max, (u8 *)&out, (u8 *)&tmp, 2, 1);
- if (ret)
- return ret;
+ buf = kzalloc(8, GFP_KERNEL | GFP_DMA);
+ if (!buf)
+ return -ENOMEM;
+
+ obuf = buf;
+ ibuf = buf + 4;
+ *obuf = out;
+ ret = max3110_write_then_read(max, obuf, ibuf, 2, 1);
+ if (ret) {
+ pr_warning(PR_FMT "%s(): get err msg %d when sending 0x%x\n",
+ __func__, ret, out);
+ goto exit;
+ }
/* If some valid data is read back */
- if (tmp & MAX3110_READ_DATA_AVAILABLE)
- receive_char(max, (tmp & 0xff));
+ if (*ibuf & MAX3110_READ_DATA_AVAILABLE) {
+ ch = *ibuf & 0xff;
+ receive_chars(max, &ch, 1);
+ }
+exit:
+ kfree(buf);
return ret;
}
-#define MAX_READ_LEN 20
/*
* This is usually used to read data from SPIC RX FIFO, which doesn't
- * need any delay like flushing character out. It returns how many
- * valide bytes are read back
+ * need any delay like flushing character out.
+ *
+ * Return how many valide bytes are read back
*/
-static int max3110_read_multi(struct uart_max3110 *max, int len, u8 *buf)
+static int max3110_read_multi(struct uart_max3110 *max, u8 *rxbuf)
{
- u16 out[MAX_READ_LEN], in[MAX_READ_LEN];
- u8 *pbuf, valid_str[MAX_READ_LEN];
- int i, j, bytelen;
+ void *buf;
+ u16 *obuf, *ibuf;
+ u8 *pbuf, valid_str[M3110_RX_FIFO_DEPTH];
+ int i, j, blen;
- if (len > MAX_READ_LEN) {
- pr_err(PR_FMT "read len %d is too large\n", len);
+ blen = M3110_RX_FIFO_DEPTH * sizeof(u16);
+ buf = kzalloc(blen * 2, GFP_KERNEL | GFP_DMA);
+ if (!buf) {
+ pr_warning(PR_FMT "%s(): fail to alloc dma buffer\n", __func__);
return 0;
}
- bytelen = len * 2;
- memset(out, 0, bytelen);
- memset(in, 0, bytelen);
+ /* tx/rx always have the same length */
+ obuf = buf;
+ ibuf = buf + blen;
- if (max3110_write_then_read(max, (u8 *)out, (u8 *)in, bytelen, 1))
+ if (max3110_write_then_read(max, obuf, ibuf, blen, 1)) {
+ kfree(buf);
return 0;
+ }
- /* If caller don't provide a buffer, then handle received char */
- pbuf = buf ? buf : valid_str;
+ /* If caller doesn't provide a buffer, then handle received char */
+ pbuf = rxbuf ? rxbuf : valid_str;
- for (i = 0, j = 0; i < len; i++) {
- if (in[i] & MAX3110_READ_DATA_AVAILABLE)
- pbuf[j++] = (u8)(in[i] & 0xff);
+ for (i = 0, j = 0; i < M3110_RX_FIFO_DEPTH; i++) {
+ if (ibuf[i] & MAX3110_READ_DATA_AVAILABLE)
+ pbuf[j++] = ibuf[i] & 0xff;
}
if (j && (pbuf == valid_str))
receive_chars(max, valid_str, j);
+ kfree(buf);
return j;
}
xmit->buf[xmit->head] = (char)ch;
xmit->head = (xmit->head + 1) & (PAGE_SIZE - 1);
}
-
-
- if (!test_and_set_bit(CON_TX_NEEDED, &max->uart_flags))
- wake_up_process(max->main_thread);
}
/*
return;
uart_console_write(&pmax->port, s, count, serial_m3110_con_putchar);
+
+ if (!test_and_set_bit(CON_TX_NEEDED, &pmax->uart_flags))
+ wake_up_process(pmax->main_thread);
}
static int __init
pr_info(PR_FMT "setting up console\n");
+ if (co->index == -1)
+ co->index = 0;
+
if (!max) {
pr_err(PR_FMT "pmax is NULL, return");
return -ENODEV;
.data = &serial_m3110_reg,
};
-#define MRST_CONSOLE (&serial_m3110_console)
-
static unsigned int serial_m3110_tx_empty(struct uart_port *port)
{
return 1;
}
#define WORDS_PER_XFER 128
-static inline void send_circ_buf(struct uart_max3110 *max,
+static void send_circ_buf(struct uart_max3110 *max,
struct circ_buf *xmit)
{
- int len, left = 0;
- u16 obuf[WORDS_PER_XFER], ibuf[WORDS_PER_XFER];
+ void *buf;
+ u16 *obuf, *ibuf;
u8 valid_str[WORDS_PER_XFER];
- int i, j;
+ int i, j, len, blen, dma_size, left, ret = 0;
+
+
+ dma_size = WORDS_PER_XFER * sizeof(u16) * 2;
+ buf = kzalloc(dma_size, GFP_KERNEL | GFP_DMA);
+ if (!buf)
+ return;
+ obuf = buf;
+ ibuf = buf + dma_size/2;
while (!uart_circ_empty(xmit)) {
left = uart_circ_chars_pending(xmit);
while (left) {
- len = (left >= WORDS_PER_XFER) ? WORDS_PER_XFER : left;
+ len = min(left, WORDS_PER_XFER);
+ blen = len * sizeof(u16);
+ memset(ibuf, 0, blen);
- memset(obuf, 0, len * 2);
- memset(ibuf, 0, len * 2);
for (i = 0; i < len; i++) {
obuf[i] = (u8)xmit->buf[xmit->tail] | WD_TAG;
xmit->tail = (xmit->tail + 1) &
(UART_XMIT_SIZE - 1);
}
- max3110_write_then_read(max, (u8 *)obuf,
- (u8 *)ibuf, len * 2, 0);
+
+ /* Fail to send msg to console is not very critical */
+ ret = max3110_write_then_read(max, obuf, ibuf, blen, 0);
+ if (ret)
+ pr_warning(PR_FMT "%s(): get err msg %d\n",
+ __func__, ret);
for (i = 0, j = 0; i < len; i++) {
if (ibuf[i] & MAX3110_READ_DATA_AVAILABLE)
- valid_str[j++] = (u8)(ibuf[i] & 0xff);
+ valid_str[j++] = ibuf[i] & 0xff;
}
if (j)
left -= len;
}
}
+
+ kfree(buf);
}
static void transmit_char(struct uart_max3110 *max)
serial_m3110_stop_tx(port);
}
-/* This will be called by uart_write() and tty_write, can't
- * go to sleep */
+/*
+ * This will be called by uart_write() and tty_write, can't
+ * go to sleep
+ */
static void serial_m3110_start_tx(struct uart_port *port)
{
struct uart_max3110 *max =
tty = port->state->port.tty;
if (!tty)
- return; /* receive some char before the tty is opened */
+ return;
while (len) {
usable = tty_buffer_request_room(tty, len);
tty_insert_flip_string(tty, str, usable);
str += usable;
port->icount.rx += usable;
- tty_flip_buffer_push(tty);
}
len -= usable;
}
+ tty_flip_buffer_push(tty);
}
-static inline void receive_char(struct uart_max3110 *max, u8 ch)
-{
- receive_chars(max, &ch, 1);
-}
-
-static void max3110_console_receive(struct uart_max3110 *max)
+/*
+ * This routine will be used in read_thread or RX IRQ handling,
+ * it will first do one round buffer read(8 words), if there is some
+ * valid RX data, will try to read 5 more rounds till all data
+ * is read out.
+ *
+ * Use stack space as data buffer to save some system load, and chose
+ * 504 Btyes as a threadhold to do a bulk push to upper tty layer when
+ * receiving bulk data, a much bigger buffer may cause stack overflow
+ */
+static void max3110_con_receive(struct uart_max3110 *max)
{
int loop = 1, num, total = 0;
u8 recv_buf[512], *pbuf;
pbuf = recv_buf;
do {
- num = max3110_read_multi(max, 8, pbuf);
+ num = max3110_read_multi(max, pbuf);
if (num) {
- loop = 10;
+ loop = 5;
pbuf += num;
total += num;
- if (total >= 500) {
+ if (total >= 504) {
receive_chars(max, recv_buf, total);
pbuf = recv_buf;
total = 0;
mutex_lock(&max->thread_mutex);
if (test_and_clear_bit(BIT_IRQ_PENDING, &max->uart_flags))
- max3110_console_receive(max);
+ max3110_con_receive(max);
/* first handle console output */
if (test_and_clear_bit(CON_TX_NEEDED, &max->uart_flags))
pr_info(PR_FMT "start read thread\n");
do {
- mutex_lock(&max->thread_mutex);
- max3110_console_receive(max);
- mutex_unlock(&max->thread_mutex);
+ /*
+ * If can't acquire the mutex, it means the main thread
+ * is running which will also perform the rx job
+ */
+ if (mutex_trylock(&max->thread_mutex)) {
+ max3110_con_receive(max);
+ mutex_unlock(&max->thread_mutex);
+ }
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ / 20);
u16 config = 0;
int ret = 0;
- if (port->line != 0)
+ if (port->line != 0) {
pr_err(PR_FMT "uart port startup failed\n");
+ return -1;
+ }
- /* firstly disable all IRQ and config it to 115200, 8n1 */
+ /* Disable all IRQ and config it to 115200, 8n1 */
config = WC_TAG | WC_FIFO_ENABLE
| WC_1_STOPBITS
| WC_8BIT_WORD
| WC_BAUD_DR2;
- ret = max3110_out(max, config);
/* as we use thread to handle tx/rx, need set low latency */
port->state->port.tty->low_latency = 1;
if (ret)
return ret;
- /* enable RX IRQ only */
+ /* Enable RX IRQ only */
config |= WC_RXA_IRQ_ENABLE;
- max3110_out(max, config);
#else
- /* if IRQ is disabled, start a read thread for input data */
+ /* If IRQ is disabled, start a read thread for input data */
max->read_thread =
kthread_run(max3110_read_thread, max, "max3110_read");
+ if (IS_ERR(max->read_thread)) {
+ ret = PTR_ERR(max->read_thread);
+ max->read_thread = NULL;
+ pr_err(PR_FMT "Can't create read thread!");
+ return ret;
+ }
+#endif
+
+ ret = max3110_out(max, config);
+ if (ret) {
+#ifdef CONFIG_MRST_MAX3110_IRQ
+ free_irq(max->irq, max);
+#else
+ kthread_stop(max->read_thread);
+ max->read_thread = NULL;
#endif
+ return ret;
+ }
max->cur_conf = config;
return 0;
static void serial_m3110_config_port(struct uart_port *port, int flags)
{
- /* give it fake type */
- port->type = PORT_PXA;
+ port->type = PORT_MAX3100;
}
static int
new_conf |= WC_7BIT_WORD;
break;
default:
+ /* We only support CS7 & CS8 */
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= CS8;
case CS8:
cval = UART_LCR_WLEN8;
new_conf |= WC_8BIT_WORD;
baud = uart_get_baud_rate(port, termios, old, 0, 230400);
- /* first calc the div for 1.8MHZ clock case */
+ /* First calc the div for 1.8MHZ clock case */
switch (baud) {
case 300:
clk_div = WC_BAUD_DR384;
if (max->clock & MAX3110_HIGH_CLK)
break;
default:
- /* pick the previous baud rate */
+ /* Pick the previous baud rate */
baud = max->baud;
clk_div = max->cur_conf & WC_BAUD_DIV_MASK;
tty_termios_encode_baud_rate(termios, baud, baud);
if (max->clock & MAX3110_HIGH_CLK) {
clk_div += 1;
- /* high clk version max3110 doesn't support B300 */
- if (baud == 300)
+ /* High clk version max3110 doesn't support B300 */
+ if (baud == 300) {
baud = 600;
+ clk_div = WC_BAUD_DR384;
+ }
if (baud == 230400)
clk_div = WC_BAUD_DR1;
tty_termios_encode_baud_rate(termios, baud, baud);
}
new_conf = (new_conf & ~WC_BAUD_DIV_MASK) | clk_div;
+
+ if (unlikely(termios->c_cflag & CMSPAR))
+ termios->c_cflag &= ~CMSPAR;
+
if (termios->c_cflag & CSTOPB)
new_conf |= WC_2_STOPBITS;
else
new_conf |= WC_TAG;
if (new_conf != max->cur_conf) {
- max3110_out(max, new_conf);
- max->cur_conf = new_conf;
- max->baud = baud;
+ if (!max3110_out(max, new_conf)) {
+ max->cur_conf = new_conf;
+ max->baud = baud;
+ }
}
}
-/* don't handle hw handshaking */
+/* Don't handle hw handshaking */
static unsigned int serial_m3110_get_mctrl(struct uart_port *port)
{
return TIOCM_DSR | TIOCM_CAR | TIOCM_DSR;
.break_ctl = serial_m3110_break_ctl,
.startup = serial_m3110_startup,
.shutdown = serial_m3110_shutdown,
- .set_termios = serial_m3110_set_termios, /* must have */
+ .set_termios = serial_m3110_set_termios,
.pm = serial_m3110_pm,
.type = serial_m3110_type,
.release_port = serial_m3110_release_port,
.major = TTY_MAJOR,
.minor = 64,
.nr = 1,
- .cons = MRST_CONSOLE,
+ .cons = &serial_m3110_console,
};
+#ifdef CONFIG_PM
static int serial_m3110_suspend(struct spi_device *spi, pm_message_t state)
{
+ struct uart_max3110 *max = spi_get_drvdata(spi);
+
+ disable_irq(max->irq);
+ uart_suspend_port(&serial_m3110_reg, &max->port);
+ max3110_out(max, max->cur_conf | WC_SW_SHDI);
return 0;
}
static int serial_m3110_resume(struct spi_device *spi)
{
+ struct uart_max3110 *max = spi_get_drvdata(spi);
+
+ max3110_out(max, max->cur_conf);
+ uart_resume_port(&serial_m3110_reg, &max->port);
+ enable_irq(max->irq);
return 0;
}
+#else
+#define serial_m3110_suspend NULL
+#define serial_m3110_resume NULL
+#endif
-static struct dw_spi_chip spi0_uart = {
- .poll_mode = 1,
- .enable_dma = 0,
- .type = SPI_FRF_SPI,
-};
-
-static int serial_m3110_probe(struct spi_device *spi)
+static int __devinit serial_m3110_probe(struct spi_device *spi)
{
struct uart_max3110 *max;
- int ret;
- unsigned char *buffer;
+ void *buffer;
u16 res;
+ int ret = 0;
+
max = kzalloc(sizeof(*max), GFP_KERNEL);
if (!max)
return -ENOMEM;
- /* set spi info */
- spi->mode = SPI_MODE_0;
+ /* Set spi info */
spi->bits_per_word = 16;
max->clock = MAX3110_HIGH_CLK;
- spi->controller_data = &spi0_uart;
spi_setup(spi);
- max->port.type = PORT_PXA; /* need apply for a max3110 type */
- max->port.fifosize = 2; /* only have 16b buffer */
+ max->port.type = PORT_MAX3100;
+ max->port.fifosize = 2; /* Only have 16b buffer */
max->port.ops = &serial_m3110_ops;
max->port.line = 0;
max->port.dev = &spi->dev;
max->port.uartclk = 115200;
max->spi = spi;
- max->name = spi->modalias; /* use spi name as the name */
+ strcpy(max->name, spi->modalias);
max->irq = (u16)spi->irq;
mutex_init(&max->thread_mutex);
ret = -ENODEV;
goto err_get_page;
}
- buffer = (unsigned char *)__get_free_page(GFP_KERNEL);
+
+ buffer = (void *)__get_free_page(GFP_KERNEL);
if (!buffer) {
ret = -ENOMEM;
goto err_get_page;
}
- max->con_xmit.buf = (unsigned char *)buffer;
- max->con_xmit.head = max->con_xmit.tail = 0;
+ max->con_xmit.buf = buffer;
+ max->con_xmit.head = 0;
+ max->con_xmit.tail = 0;
max->main_thread = kthread_run(max3110_main_thread,
max, "max3110_main");
goto err_kthread;
}
+ spi_set_drvdata(spi, max);
pmax = max;
- /* give membase a psudo value to pass serial_core's check */
+
+ /* Give membase a psudo value to pass serial_core's check */
max->port.membase = (void *)0xff110000;
uart_add_one_port(&serial_m3110_reg, &max->port);
err_kthread:
free_page((unsigned long)buffer);
err_get_page:
- pmax = NULL;
kfree(max);
return ret;
}
-static int max3110_remove(struct spi_device *dev)
+static int __devexit serial_m3110_remove(struct spi_device *dev)
{
- struct uart_max3110 *max = pmax;
+ struct uart_max3110 *max = spi_get_drvdata(dev);
- if (!pmax)
+ if (!max)
return 0;
- pmax = NULL;
uart_remove_one_port(&serial_m3110_reg, &max->port);
free_page((unsigned long)max->con_xmit.buf);
.owner = THIS_MODULE,
},
.probe = serial_m3110_probe,
- .remove = __devexit_p(max3110_remove),
+ .remove = __devexit_p(serial_m3110_remove),
.suspend = serial_m3110_suspend,
.resume = serial_m3110_resume,
};
-
-int __init serial_m3110_init(void)
+static int __init serial_m3110_init(void)
{
int ret = 0;
return ret;
}
-void __exit serial_m3110_exit(void)
+static void __exit serial_m3110_exit(void)
{
spi_unregister_driver(&uart_max3110_driver);
uart_unregister_driver(&serial_m3110_reg);
module_init(serial_m3110_init);
module_exit(serial_m3110_exit);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
MODULE_ALIAS("max3110-uart");
projects / karo-tx-linux.git / commitdiff