diff options
Diffstat (limited to 'drivers/tty/serial/max3100.c')
-rw-r--r-- | drivers/tty/serial/max3100.c | 340 |
1 files changed, 138 insertions, 202 deletions
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c index 5efb2b593be3..fda63918d1eb 100644 --- a/drivers/tty/serial/max3100.c +++ b/drivers/tty/serial/max3100.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0+ /* - * * Copyright (C) 2008 Christian Pellegrin <chripell@evolware.org> * * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have @@ -8,24 +7,6 @@ * 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 */ @@ -35,18 +16,23 @@ /* 4 MAX3100s should be enough for everyone */ #define MAX_MAX3100 4 +#include <linux/container_of.h> #include <linux/delay.h> -#include <linux/slab.h> #include <linux/device.h> +#include <linux/freezer.h> +#include <linux/mod_devicetable.h> #include <linux/module.h> +#include <linux/pm.h> +#include <linux/property.h> #include <linux/serial_core.h> #include <linux/serial.h> +#include <linux/slab.h> #include <linux/spi/spi.h> -#include <linux/freezer.h> -#include <linux/tty.h> #include <linux/tty_flip.h> +#include <linux/tty.h> +#include <linux/types.h> -#include <linux/serial_max3100.h> +#include <asm/unaligned.h> #define MAX3100_C (1<<14) #define MAX3100_D (0<<14) @@ -110,10 +96,8 @@ struct max3100_port { #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_commit; /* need to change loopback */ int loopback; /* 1 if we are in loopback mode */ /* for handling irqs: need workqueue since we do spi_sync */ @@ -124,15 +108,14 @@ struct max3100_port { /* 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 inline struct max3100_port *to_max3100_port(struct uart_port *port) +{ + return container_of(port, struct max3100_port, port); +} + static struct max3100_port *max3100s[MAX_MAX3100]; /* the chips */ static DEFINE_MUTEX(max3100s_lock); /* race on probe */ @@ -170,28 +153,10 @@ static void max3100_calc_parity(struct max3100_port *s, u16 *c) *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 && !freezing(current) && !s->suspending) - queue_work(s->workqueue, &s->work); -} - -static void max3100_timeout(struct timer_list *t) -{ - struct max3100_port *s = from_timer(s, t, timer); - - 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; + __be16 etx, erx; int status; struct spi_transfer tran = { .tx_buf = &etx, @@ -213,7 +178,7 @@ static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx) return 0; } -static int max3100_handlerx(struct max3100_port *s, u16 rx) +static int max3100_handlerx_unlocked(struct max3100_port *s, u16 rx) { unsigned int status = 0; int ret = 0, cts; @@ -254,13 +219,25 @@ static int max3100_handlerx(struct max3100_port *s, u16 rx) return ret; } +static int max3100_handlerx(struct max3100_port *s, u16 rx) +{ + unsigned long flags; + int ret; + + uart_port_lock_irqsave(&s->port, &flags); + ret = max3100_handlerx_unlocked(s, rx); + uart_port_unlock_irqrestore(&s->port, flags); + return ret; +} + static void max3100_work(struct work_struct *w) { struct max3100_port *s = container_of(w, struct max3100_port, work); + struct tty_port *tport = &s->port.state->port; + unsigned char ch; + int conf, cconf, cloopback, crts; int rxchars; u16 tx, rx; - int conf, cconf, crts; - struct circ_buf *xmit = &s->port.state->xmit; dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -270,11 +247,15 @@ static void max3100_work(struct work_struct *w) conf = s->conf; cconf = s->conf_commit; s->conf_commit = 0; + cloopback = s->loopback_commit; + s->loopback_commit = 0; crts = s->rts_commit; s->rts_commit = 0; spin_unlock(&s->conf_lock); if (cconf) max3100_sr(s, MAX3100_WC | conf, &rx); + if (cloopback) + max3100_sr(s, 0x4001, &rx); if (crts) { max3100_sr(s, MAX3100_WD | MAX3100_TE | (s->rts ? MAX3100_RTS : 0), &rx); @@ -290,10 +271,9 @@ static void max3100_work(struct work_struct *w) 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]; - uart_xmit_advance(&s->port, 1); + } else if (!uart_tx_stopped(&s->port) && + uart_fifo_get(&s->port, &ch)) { + tx = ch; } if (tx != 0xffff) { max3100_calc_parity(s, &tx); @@ -307,19 +287,33 @@ static void max3100_work(struct work_struct *w) tty_flip_buffer_push(&s->port.state->port); rxchars = 0; } - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(&s->port); } while (!s->force_end_work && !freezing(current) && ((rx & MAX3100_R) || - (!uart_circ_empty(xmit) && + (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(&s->port)))); if (rxchars > 0) tty_flip_buffer_push(&s->port.state->port); } +static void max3100_dowork(struct max3100_port *s) +{ + if (!s->force_end_work && !freezing(current) && !s->suspending) + queue_work(s->workqueue, &s->work); +} + +static void max3100_timeout(struct timer_list *t) +{ + struct max3100_port *s = from_timer(s, t, timer); + + max3100_dowork(s); + mod_timer(&s->timer, jiffies + uart_poll_timeout(&s->port)); +} + static irqreturn_t max3100_irq(int irqno, void *dev_id) { struct max3100_port *s = dev_id; @@ -332,20 +326,15 @@ static irqreturn_t max3100_irq(int irqno, void *dev_id) static void max3100_enable_ms(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); - if (s->poll_time > 0) - mod_timer(&s->timer, jiffies); + 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); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -354,9 +343,7 @@ static void max3100_start_tx(struct uart_port *port) static void max3100_stop_rx(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -370,9 +357,7 @@ static void max3100_stop_rx(struct uart_port *port) static unsigned int max3100_tx_empty(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -383,9 +368,7 @@ static unsigned int max3100_tx_empty(struct uart_port *port) static unsigned int max3100_get_mctrl(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -397,21 +380,25 @@ static unsigned int max3100_get_mctrl(struct uart_port *port) 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; + struct max3100_port *s = to_max3100_port(port); + int loopback, rts; dev_dbg(&s->spi->dev, "%s\n", __func__); + loopback = (mctrl & TIOCM_LOOP) > 0; rts = (mctrl & TIOCM_RTS) > 0; spin_lock(&s->conf_lock); + if (s->loopback != loopback) { + s->loopback = loopback; + s->loopback_commit = 1; + } if (s->rts != rts) { s->rts = rts; s->rts_commit = 1; - max3100_dowork(s); } + if (s->loopback_commit || s->rts_commit) + max3100_dowork(s); spin_unlock(&s->conf_lock); } @@ -419,10 +406,9 @@ static void max3100_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); - int baud = 0; + struct max3100_port *s = to_max3100_port(port); + unsigned int baud = port->uartclk / 16; + unsigned int baud230400 = (baud == 230400) ? 1 : 0; unsigned cflag; u32 param_new, param_mask, parity = 0; @@ -435,40 +421,40 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios, param_new = s->conf & MAX3100_BAUD; switch (baud) { case 300: - if (s->crystal) + if (baud230400) baud = s->baud; else param_new = 15; break; case 600: - param_new = 14 + s->crystal; + param_new = 14 + baud230400; break; case 1200: - param_new = 13 + s->crystal; + param_new = 13 + baud230400; break; case 2400: - param_new = 12 + s->crystal; + param_new = 12 + baud230400; break; case 4800: - param_new = 11 + s->crystal; + param_new = 11 + baud230400; break; case 9600: - param_new = 10 + s->crystal; + param_new = 10 + baud230400; break; case 19200: - param_new = 9 + s->crystal; + param_new = 9 + baud230400; break; case 38400: - param_new = 8 + s->crystal; + param_new = 8 + baud230400; break; case 57600: - param_new = 1 + s->crystal; + param_new = 1 + baud230400; break; case 115200: - param_new = 0 + s->crystal; + param_new = 0 + baud230400; break; case 230400: - if (s->crystal) + if (baud230400) param_new = 0; else baud = s->baud; @@ -520,9 +506,7 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios, MAX3100_STATUS_PE | MAX3100_STATUS_FE | MAX3100_STATUS_OE; - if (s->poll_time > 0) - del_timer_sync(&s->timer); - + del_timer_sync(&s->timer); uart_update_timeout(port, termios->c_cflag, baud); spin_lock(&s->conf_lock); @@ -538,9 +522,8 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios, static void max3100_shutdown(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); + u16 rx; dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -549,38 +532,29 @@ static void max3100_shutdown(struct uart_port *port) s->force_end_work = 1; - if (s->poll_time > 0) - del_timer_sync(&s->timer); + del_timer_sync(&s->timer); if (s->workqueue) { destroy_workqueue(s->workqueue); s->workqueue = NULL; } - if (s->irq) - free_irq(s->irq, s); + if (port->irq) + free_irq(port->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); - } + max3100_sr(s, MAX3100_WC | MAX3100_SHDN, &rx); } static int max3100_startup(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); char b[12]; + int ret; dev_dbg(&s->spi->dev, "%s\n", __func__); s->conf = MAX3100_RM; - s->baud = s->crystal ? 230400 : 115200; + s->baud = port->uartclk / 16; s->rx_enabled = 1; if (s->suspending) @@ -598,23 +572,15 @@ static int max3100_startup(struct uart_port *port) } 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; + ret = request_irq(port->irq, max3100_irq, IRQF_TRIGGER_FALLING, "max3100", s); + if (ret < 0) { + dev_warn(&s->spi->dev, "cannot allocate irq %d\n", port->irq); + port->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 */ @@ -627,9 +593,7 @@ static int max3100_startup(struct uart_port *port) static const char *max3100_type(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -638,18 +602,14 @@ static const char *max3100_type(struct uart_port *port) static void max3100_release_port(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_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); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -660,9 +620,7 @@ static void max3100_config_port(struct uart_port *port, int flags) static int max3100_verify_port(struct uart_port *port, struct serial_struct *ser) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); int ret = -EINVAL; dev_dbg(&s->spi->dev, "%s\n", __func__); @@ -674,18 +632,14 @@ static int max3100_verify_port(struct uart_port *port, static void max3100_stop_tx(struct uart_port *port) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_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); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); return 0; @@ -693,9 +647,7 @@ static int max3100_request_port(struct uart_port *port) static void max3100_break_ctl(struct uart_port *port, int break_state) { - struct max3100_port *s = container_of(port, - struct max3100_port, - port); + struct max3100_port *s = to_max3100_port(port); dev_dbg(&s->spi->dev, "%s\n", __func__); } @@ -731,74 +683,59 @@ static int uart_driver_registered; static int max3100_probe(struct spi_device *spi) { + struct device *dev = &spi->dev; int i, retval; - struct plat_max3100 *pdata; - u16 tx, rx; + u16 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; + return dev_err_probe(dev, retval, "Couldn't register max3100 uart driver\n"); } + + uart_driver_registered = 1; } 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; + return dev_err_probe(dev, -ENOMEM, "too many MAX3100 chips\n"); } 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); spi_set_drvdata(spi, max3100s[i]); - pdata = dev_get_platdata(&spi->dev); - max3100s[i]->crystal = pdata->crystal; - max3100s[i]->loopback = pdata->loopback; - max3100s[i]->poll_time = msecs_to_jiffies(pdata->poll_time); - 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; timer_setup(&max3100s[i]->timer, max3100_timeout, 0); 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.irq = spi->irq; 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; + + /* Read clock frequency from a property, uart_add_one_port() will fail if it's not set */ + device_property_read_u32(dev, "clock-frequency", &max3100s[i]->port.uartclk); + 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); + dev_err_probe(dev, retval, "uart_add_one_port failed for line %d\n", i); /* 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); - } + max3100_sr(max3100s[i], MAX3100_WC | MAX3100_SHDN, &rx); mutex_unlock(&max3100s_lock); return 0; } @@ -830,32 +767,25 @@ static void max3100_remove(struct spi_device *spi) } pr_debug("removing max3100 driver\n"); uart_unregister_driver(&max3100_uart_driver); + uart_driver_registered = 0; mutex_unlock(&max3100s_lock); } -#ifdef CONFIG_PM_SLEEP - static int max3100_suspend(struct device *dev) { struct max3100_port *s = dev_get_drvdata(dev); + u16 rx; dev_dbg(&s->spi->dev, "%s\n", __func__); - disable_irq(s->irq); + disable_irq(s->port.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); - } + /* no HW suspend, so do SW one */ + max3100_sr(s, MAX3100_WC | MAX3100_SHDN, &rx); return 0; } @@ -865,12 +795,10 @@ static int max3100_resume(struct device *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); + enable_irq(s->port.irq); s->conf_commit = 1; if (s->workqueue) @@ -879,20 +807,29 @@ static int max3100_resume(struct device *dev) return 0; } -static SIMPLE_DEV_PM_OPS(max3100_pm_ops, max3100_suspend, max3100_resume); -#define MAX3100_PM_OPS (&max3100_pm_ops) +static DEFINE_SIMPLE_DEV_PM_OPS(max3100_pm_ops, max3100_suspend, max3100_resume); + +static const struct spi_device_id max3100_spi_id[] = { + { "max3100" }, + { } +}; +MODULE_DEVICE_TABLE(spi, max3100_spi_id); -#else -#define MAX3100_PM_OPS NULL -#endif +static const struct of_device_id max3100_of_match[] = { + { .compatible = "maxim,max3100" }, + { } +}; +MODULE_DEVICE_TABLE(of, max3100_of_match); static struct spi_driver max3100_driver = { .driver = { .name = "max3100", - .pm = MAX3100_PM_OPS, + .of_match_table = max3100_of_match, + .pm = pm_sleep_ptr(&max3100_pm_ops), }, .probe = max3100_probe, .remove = max3100_remove, + .id_table = max3100_spi_id, }; module_spi_driver(max3100_driver); @@ -900,4 +837,3 @@ module_spi_driver(max3100_driver); MODULE_DESCRIPTION("MAX3100 driver"); MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>"); MODULE_LICENSE("GPL"); -MODULE_ALIAS("spi:max3100"); |