diff options
Diffstat (limited to 'drivers/tty/serial/sccnxp.c')
-rw-r--r-- | drivers/tty/serial/sccnxp.c | 179 |
1 files changed, 117 insertions, 62 deletions
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c index 418b495..08dbfb8 100644 --- a/drivers/tty/serial/sccnxp.c +++ b/drivers/tty/serial/sccnxp.c @@ -15,6 +15,7 @@ #define SUPPORT_SYSRQ #endif +#include <linux/err.h> #include <linux/module.h> #include <linux/device.h> #include <linux/console.h> @@ -23,8 +24,9 @@ #include <linux/io.h> #include <linux/tty.h> #include <linux/tty_flip.h> +#include <linux/spinlock.h> #include <linux/platform_device.h> -#include <linux/platform_data/sccnxp.h> +#include <linux/platform_data/serial-sccnxp.h> #define SCCNXP_NAME "uart-sccnxp" #define SCCNXP_MAJOR 204 @@ -106,6 +108,7 @@ enum { struct sccnxp_port { struct uart_driver uart; struct uart_port port[SCCNXP_MAX_UARTS]; + bool opened[SCCNXP_MAX_UARTS]; const char *name; int irq; @@ -122,7 +125,10 @@ struct sccnxp_port { struct console console; #endif - struct mutex sccnxp_mutex; + spinlock_t lock; + + bool poll; + struct timer_list timer; struct sccnxp_pdata pdata; }; @@ -174,14 +180,12 @@ static int sccnxp_update_best_err(int a, int b, int *besterr) return 1; } -struct baud_table { +static const struct { u8 csr; u8 acr; u8 mr0; int baud; -}; - -const struct baud_table baud_std[] = { +} baud_std[] = { { 0, ACR_BAUD0, MR0_BAUD_NORMAL, 50, }, { 0, ACR_BAUD1, MR0_BAUD_NORMAL, 75, }, { 1, ACR_BAUD0, MR0_BAUD_NORMAL, 110, }, @@ -285,10 +289,6 @@ static void sccnxp_handle_rx(struct uart_port *port) { u8 sr; unsigned int ch, flag; - struct tty_struct *tty = tty_port_tty_get(&port->state->port); - - if (!tty) - return; for (;;) { sr = sccnxp_port_read(port, SCCNXP_SR_REG); @@ -304,14 +304,19 @@ static void sccnxp_handle_rx(struct uart_port *port) if (unlikely(sr)) { if (sr & SR_BRK) { port->icount.brk++; + sccnxp_port_write(port, SCCNXP_CR_REG, + CR_CMD_BREAK_RESET); if (uart_handle_break(port)) continue; } else if (sr & SR_PE) port->icount.parity++; else if (sr & SR_FE) port->icount.frame++; - else if (sr & SR_OVR) + else if (sr & SR_OVR) { port->icount.overrun++; + sccnxp_port_write(port, SCCNXP_CR_REG, + CR_CMD_STATUS_RESET); + } sr &= port->read_status_mask; if (sr & SR_BRK) @@ -333,9 +338,7 @@ static void sccnxp_handle_rx(struct uart_port *port) uart_insert_char(port, sr, SR_OVR, ch, flag); } - tty_flip_buffer_push(tty); - - tty_kref_put(tty); + tty_flip_buffer_push(&port->state->port); } static void sccnxp_handle_tx(struct uart_port *port) @@ -377,31 +380,48 @@ static void sccnxp_handle_tx(struct uart_port *port) uart_write_wakeup(port); } -static irqreturn_t sccnxp_ist(int irq, void *dev_id) +static void sccnxp_handle_events(struct sccnxp_port *s) { int i; u8 isr; - struct sccnxp_port *s = (struct sccnxp_port *)dev_id; - - mutex_lock(&s->sccnxp_mutex); - for (;;) { + do { isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG); isr &= s->imr; if (!isr) break; - dev_dbg(s->port[0].dev, "IRQ status: 0x%02x\n", isr); - for (i = 0; i < s->uart.nr; i++) { - if (isr & ISR_RXRDY(i)) + if (s->opened[i] && (isr & ISR_RXRDY(i))) sccnxp_handle_rx(&s->port[i]); - if (isr & ISR_TXRDY(i)) + if (s->opened[i] && (isr & ISR_TXRDY(i))) sccnxp_handle_tx(&s->port[i]); } - } + } while (1); +} + +static void sccnxp_timer(unsigned long data) +{ + struct sccnxp_port *s = (struct sccnxp_port *)data; + unsigned long flags; - mutex_unlock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); + sccnxp_handle_events(s); + spin_unlock_irqrestore(&s->lock, flags); + + if (!timer_pending(&s->timer)) + mod_timer(&s->timer, jiffies + + usecs_to_jiffies(s->pdata.poll_time_us)); +} + +static irqreturn_t sccnxp_ist(int irq, void *dev_id) +{ + struct sccnxp_port *s = (struct sccnxp_port *)dev_id; + unsigned long flags; + + spin_lock_irqsave(&s->lock, flags); + sccnxp_handle_events(s); + spin_unlock_irqrestore(&s->lock, flags); return IRQ_HANDLED; } @@ -409,8 +429,9 @@ static irqreturn_t sccnxp_ist(int irq, void *dev_id) static void sccnxp_start_tx(struct uart_port *port) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); /* Set direction to output */ if (s->flags & SCCNXP_HAVE_IO) @@ -418,7 +439,7 @@ static void sccnxp_start_tx(struct uart_port *port) sccnxp_enable_irq(port, IMR_TXRDY); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static void sccnxp_stop_tx(struct uart_port *port) @@ -429,20 +450,22 @@ static void sccnxp_stop_tx(struct uart_port *port) static void sccnxp_stop_rx(struct uart_port *port) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static unsigned int sccnxp_tx_empty(struct uart_port *port) { u8 val; + unsigned long flags; struct sccnxp_port *s = dev_get_drvdata(port->dev); - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); val = sccnxp_port_read(port, SCCNXP_SR_REG); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); return (val & SR_TXEMT) ? TIOCSER_TEMT : 0; } @@ -455,28 +478,30 @@ static void sccnxp_enable_ms(struct uart_port *port) static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; if (!(s->flags & SCCNXP_HAVE_IO)) return; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR); sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static unsigned int sccnxp_get_mctrl(struct uart_port *port) { u8 bitmask, ipr; + unsigned long flags; struct sccnxp_port *s = dev_get_drvdata(port->dev); unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR; if (!(s->flags & SCCNXP_HAVE_IO)) return mctrl; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG); @@ -505,7 +530,7 @@ static unsigned int sccnxp_get_mctrl(struct uart_port *port) mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0; } - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); return mctrl; } @@ -513,21 +538,23 @@ static unsigned int sccnxp_get_mctrl(struct uart_port *port) static void sccnxp_break_ctl(struct uart_port *port, int break_state) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); sccnxp_port_write(port, SCCNXP_CR_REG, break_state ? CR_CMD_START_BREAK : CR_CMD_STOP_BREAK); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static void sccnxp_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; u8 mr1, mr2; int baud; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); /* Mask termios capabilities we don't support */ termios->c_cflag &= ~CMSPAR; @@ -594,20 +621,22 @@ static void sccnxp_set_termios(struct uart_port *port, /* Update timeout according to new baud rate */ uart_update_timeout(port, termios->c_cflag, baud); + /* Report actual baudrate back to core */ if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, baud, baud); /* Enable RX & TX */ sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static int sccnxp_startup(struct uart_port *port) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); if (s->flags & SCCNXP_HAVE_IO) { /* Outputs are controlled manually */ @@ -626,7 +655,9 @@ static int sccnxp_startup(struct uart_port *port) /* Enable RX interrupt */ sccnxp_enable_irq(port, IMR_RXRDY); - mutex_unlock(&s->sccnxp_mutex); + s->opened[port->line] = 1; + + spin_unlock_irqrestore(&s->lock, flags); return 0; } @@ -634,8 +665,11 @@ static int sccnxp_startup(struct uart_port *port) static void sccnxp_shutdown(struct uart_port *port) { struct sccnxp_port *s = dev_get_drvdata(port->dev); + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); + + s->opened[port->line] = 0; /* Disable interrupts */ sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY); @@ -647,7 +681,7 @@ static void sccnxp_shutdown(struct uart_port *port) if (s->flags & SCCNXP_HAVE_IO) sccnxp_set_bit(port, DIR_OP, 0); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static const char *sccnxp_type(struct uart_port *port) @@ -721,10 +755,11 @@ static void sccnxp_console_write(struct console *co, const char *c, unsigned n) { struct sccnxp_port *s = (struct sccnxp_port *)co->data; struct uart_port *port = &s->port[co->index]; + unsigned long flags; - mutex_lock(&s->sccnxp_mutex); + spin_lock_irqsave(&s->lock, flags); uart_console_write(port, c, n, sccnxp_console_putchar); - mutex_unlock(&s->sccnxp_mutex); + spin_unlock_irqrestore(&s->lock, flags); } static int sccnxp_console_setup(struct console *co, char *options) @@ -763,7 +798,7 @@ static int sccnxp_probe(struct platform_device *pdev) } platform_set_drvdata(pdev, s); - mutex_init(&s->sccnxp_mutex); + spin_lock_init(&s->lock); /* Individual chip settings */ switch (chiptype) { @@ -860,11 +895,19 @@ static int sccnxp_probe(struct platform_device *pdev) } else memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata)); - s->irq = platform_get_irq(pdev, 0); - if (s->irq <= 0) { - dev_err(&pdev->dev, "Missing irq resource data\n"); - ret = -ENXIO; - goto err_out; + if (s->pdata.poll_time_us) { + dev_info(&pdev->dev, "Using poll mode, resolution %u usecs\n", + s->pdata.poll_time_us); + s->poll = 1; + } + + if (!s->poll) { + s->irq = platform_get_irq(pdev, 0); + if (s->irq < 0) { + dev_err(&pdev->dev, "Missing irq resource data\n"); + ret = -ENXIO; + goto err_out; + } } /* Check input frequency */ @@ -875,10 +918,9 @@ static int sccnxp_probe(struct platform_device *pdev) goto err_out; } - membase = devm_request_and_ioremap(&pdev->dev, res); - if (!membase) { - dev_err(&pdev->dev, "Failed to ioremap\n"); - ret = -EIO; + membase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(membase)) { + ret = PTR_ERR(membase); goto err_out; } @@ -929,13 +971,23 @@ static int sccnxp_probe(struct platform_device *pdev) if (s->pdata.init) s->pdata.init(); - ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL, sccnxp_ist, - IRQF_TRIGGER_FALLING | IRQF_ONESHOT, - dev_name(&pdev->dev), s); - if (!ret) + if (!s->poll) { + ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL, + sccnxp_ist, + IRQF_TRIGGER_FALLING | + IRQF_ONESHOT, + dev_name(&pdev->dev), s); + if (!ret) + return 0; + + dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq); + } else { + init_timer(&s->timer); + setup_timer(&s->timer, sccnxp_timer, (unsigned long)s); + mod_timer(&s->timer, jiffies + + usecs_to_jiffies(s->pdata.poll_time_us)); return 0; - - dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq); + } err_out: platform_set_drvdata(pdev, NULL); @@ -948,7 +1000,10 @@ static int sccnxp_remove(struct platform_device *pdev) int i; struct sccnxp_port *s = platform_get_drvdata(pdev); - devm_free_irq(&pdev->dev, s->irq, s); + if (!s->poll) + devm_free_irq(&pdev->dev, s->irq, s); + else + del_timer_sync(&s->timer); for (i = 0; i < s->uart.nr; i++) uart_remove_one_port(&s->uart, &s->port[i]); |