diff options
| -rw-r--r-- | drivers/serial/mrst_max3110.c | 327 | ||||
| -rw-r--r-- | drivers/serial/mrst_max3110.h | 1 |
2 files changed, 201 insertions, 127 deletions
diff --git a/drivers/serial/mrst_max3110.c b/drivers/serial/mrst_max3110.c index 51c15f58e01e..af8db27f9e87 100644 --- a/drivers/serial/mrst_max3110.c +++ b/drivers/serial/mrst_max3110.c @@ -1,7 +1,7 @@ /* - * 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, @@ -32,18 +32,13 @@ #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" @@ -56,7 +51,7 @@ 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; @@ -67,35 +62,30 @@ struct uart_max3110 { 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; @@ -104,7 +94,7 @@ int max3110_write_then_read(struct uart_max3110 *max, 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; @@ -113,58 +103,80 @@ int max3110_write_then_read(struct uart_max3110 *max, 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; } @@ -178,10 +190,6 @@ static void serial_m3110_con_putchar(struct uart_port *port, int ch) 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); } /* @@ -197,6 +205,9 @@ static void serial_m3110_con_write(struct console *co, 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 @@ -210,6 +221,9 @@ serial_m3110_con_setup(struct console *co, char *options) 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; @@ -240,8 +254,6 @@ static struct console serial_m3110_console = { .data = &serial_m3110_reg, }; -#define MRST_CONSOLE (&serial_m3110_console) - static unsigned int serial_m3110_tx_empty(struct uart_port *port) { return 1; @@ -259,32 +271,44 @@ static void serial_m3110_stop_rx(struct uart_port *port) } #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) @@ -294,6 +318,8 @@ static inline void send_circ_buf(struct uart_max3110 *max, left -= len; } } + + kfree(buf); } static void transmit_char(struct uart_max3110 *max) @@ -313,8 +339,10 @@ 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 = @@ -336,7 +364,7 @@ static void receive_chars(struct uart_max3110 *max, unsigned char *str, int len) 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); @@ -344,32 +372,37 @@ static void receive_chars(struct uart_max3110 *max, unsigned char *str, int 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; @@ -397,7 +430,7 @@ static int max3110_main_thread(void *_max) 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)) @@ -434,9 +467,14 @@ static int max3110_read_thread(void *_max) 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); @@ -453,15 +491,16 @@ static int serial_m3110_startup(struct uart_port *port) 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; @@ -472,14 +511,30 @@ static int serial_m3110_startup(struct uart_port *port) 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; @@ -516,8 +571,7 @@ static int serial_m3110_request_port(struct uart_port *port) 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 @@ -552,6 +606,9 @@ serial_m3110_set_termios(struct uart_port *port, struct ktermios *termios, 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; @@ -560,7 +617,7 @@ serial_m3110_set_termios(struct uart_port *port, struct ktermios *termios, 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; @@ -596,7 +653,7 @@ serial_m3110_set_termios(struct uart_port *port, struct ktermios *termios, 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); @@ -604,15 +661,21 @@ serial_m3110_set_termios(struct uart_port *port, struct ktermios *termios, 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 @@ -632,13 +695,14 @@ serial_m3110_set_termios(struct uart_port *port, struct ktermios *termios, 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; @@ -672,7 +736,7 @@ struct uart_ops serial_m3110_ops = { .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, @@ -688,52 +752,60 @@ static struct uart_driver serial_m3110_reg = { .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); @@ -755,13 +827,15 @@ static int serial_m3110_probe(struct spi_device *spi) 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"); @@ -770,8 +844,10 @@ static int serial_m3110_probe(struct spi_device *spi) 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); @@ -780,19 +856,17 @@ static int serial_m3110_probe(struct spi_device *spi) 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); @@ -811,13 +885,12 @@ static struct spi_driver uart_max3110_driver = { .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; @@ -832,7 +905,7 @@ int __init serial_m3110_init(void) 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); @@ -841,5 +914,5 @@ void __exit serial_m3110_exit(void) module_init(serial_m3110_init); module_exit(serial_m3110_exit); -MODULE_LICENSE("GPL"); +MODULE_LICENSE("GPL v2"); MODULE_ALIAS("max3110-uart"); diff --git a/drivers/serial/mrst_max3110.h b/drivers/serial/mrst_max3110.h index 363478acb2c3..d1ef43af397c 100644 --- a/drivers/serial/mrst_max3110.h +++ b/drivers/serial/mrst_max3110.h @@ -56,4 +56,5 @@ #define WC_BAUD_DR192 (0xE) #define WC_BAUD_DR384 (0xF) +#define M3110_RX_FIFO_DEPTH 8 #endif |
