On 27/09/2014 11:46, Janusz Uzycki wrote: > Handle CTS/DSR/RI/DCD GPIO interrupts in mxs-auart. > > Signed-off-by: Janusz Uzycki <[email protected]> > --- > drivers/tty/serial/mxs-auart.c | 176 ++++++++++++++++++++++++++- > 1 file changed, 174 insertions(+), 2 deletions(-) > > diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c > index fdfa8a9..ab127a2 100644 > --- a/drivers/tty/serial/mxs-auart.c > +++ b/drivers/tty/serial/mxs-auart.c > @@ -42,7 +42,10 @@ > > #include <asm/cacheflush.h> > > +#include <linux/gpio.h> > +#include <linux/gpio/consumer.h> > #include <linux/err.h> > +#include <linux/irq.h> > #include "serial_mctrl_gpio.h" > > #define MXS_AUART_PORTS 5 > @@ -146,6 +149,7 @@ struct mxs_auart_port { > #define MXS_AUART_DMA_RX_READY 3 /* bit 3 */ > #define MXS_AUART_RTSCTS 4 /* bit 4 */ > unsigned long flags; > + unsigned int mctrl_prev; > enum mxs_auart_type devtype; > > unsigned int irq; > @@ -163,6 +167,8 @@ struct mxs_auart_port { > void *rx_dma_buf; > > struct mctrl_gpios *gpios; > + int gpio_irq[UART_GPIO_MAX]; > + bool ms_irq_enabled; > }; > > static struct platform_device_id mxs_auart_devtype[] = { > @@ -427,6 +433,29 @@ static void mxs_auart_set_mctrl(struct uart_port *u, > unsigned mctrl) > mctrl_gpio_set(s->gpios, mctrl); > } > > +#define MCTRL_ANY_DELTA (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS) > +static u32 mxs_auart_modem_status(struct mxs_auart_port *s, u32 mctrl) > +{ > + u32 mctrl_diff; > + > + mctrl_diff = mctrl ^ s->mctrl_prev; > + s->mctrl_prev = mctrl; > + if (mctrl_diff & MCTRL_ANY_DELTA && s->ms_irq_enabled && > + s->port.state != NULL) { > + if (mctrl_diff & TIOCM_RI) > + s->port.icount.rng++; > + if (mctrl_diff & TIOCM_DSR) > + s->port.icount.dsr++; > + if (mctrl_diff & TIOCM_CD) > + uart_handle_dcd_change(&s->port, mctrl & TIOCM_CD); > + if (mctrl_diff & TIOCM_CTS) > + uart_handle_cts_change(&s->port, mctrl & TIOCM_CTS); > + > + wake_up_interruptible(&s->port.state->port.delta_msr_wait); > + } > + return mctrl; > +} > + > static u32 mxs_auart_get_mctrl(struct uart_port *u) > { > struct mxs_auart_port *s = to_auart_port(u); > @@ -444,6 +473,64 @@ static u32 mxs_auart_get_mctrl(struct uart_port *u) > return mctrl_gpio_get(s->gpios, &mctrl); > } > > +/* > + * Enable modem status interrupts > + */ > +static void mxs_auart_enable_ms(struct uart_port *port) > +{ > + struct mxs_auart_port *s = to_auart_port(port); > + > + /* > + * Interrupt should not be enabled twice > + */ > + if (s->ms_irq_enabled) > + return; > + > + s->ms_irq_enabled = true; > + > + if (s->gpio_irq[UART_GPIO_CTS] >= 0) > + enable_irq(s->gpio_irq[UART_GPIO_CTS]); > + /* TODO: enable AUART_INTR_CTSMIEN otherwise */ > + > + if (s->gpio_irq[UART_GPIO_DSR] >= 0) > + enable_irq(s->gpio_irq[UART_GPIO_DSR]); > + > + if (s->gpio_irq[UART_GPIO_RI] >= 0) > + enable_irq(s->gpio_irq[UART_GPIO_RI]); > + > + if (s->gpio_irq[UART_GPIO_DCD] >= 0) > + enable_irq(s->gpio_irq[UART_GPIO_DCD]); > +} > + > +/* > + * Disable modem status interrupts > + */ > +static void mxs_auart_disable_ms(struct uart_port *port) > +{ > + struct mxs_auart_port *s = to_auart_port(port); > + > + /* > + * Interrupt should not be disabled twice > + */ > + if (!s->ms_irq_enabled) > + return; > + > + s->ms_irq_enabled = false; > + > + if (s->gpio_irq[UART_GPIO_CTS] >= 0) > + disable_irq(s->gpio_irq[UART_GPIO_CTS]); > + /* TODO: disable AUART_INTR_CTSMIEN otherwise */ > + > + if (s->gpio_irq[UART_GPIO_DSR] >= 0) > + disable_irq(s->gpio_irq[UART_GPIO_DSR]); > + > + if (s->gpio_irq[UART_GPIO_RI] >= 0) > + disable_irq(s->gpio_irq[UART_GPIO_RI]); > + > + if (s->gpio_irq[UART_GPIO_DCD] >= 0) > + disable_irq(s->gpio_irq[UART_GPIO_DCD]); > +} > + > static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s); > static void dma_rx_callback(void *arg) > { > @@ -692,6 +779,12 @@ static void mxs_auart_settermios(struct uart_port *u, > dev_err(s->dev, "We can not start up the DMA.\n"); > } > } > + > + /* CTS flow-control and modem-status interrupts */ > + if (UART_ENABLE_MS(u, termios->c_cflag)) > + mxs_auart_enable_ms(u); > + else > + mxs_auart_disable_ms(u); > } > > static irqreturn_t mxs_auart_irq_handle(int irq, void *context) > @@ -709,9 +802,20 @@ static irqreturn_t mxs_auart_irq_handle(int irq, void > *context) > | AUART_INTR_CTSMIS), > s->port.membase + AUART_INTR_CLR); > > + /* > + * Dealing with GPIO interrupt > + */ > + if (irq == s->gpio_irq[UART_GPIO_CTS] || > + irq == s->gpio_irq[UART_GPIO_DCD] || > + irq == s->gpio_irq[UART_GPIO_DSR] || > + irq == s->gpio_irq[UART_GPIO_RI]) > + mxs_auart_modem_status(s, > + mctrl_gpio_get(s->gpios, &s->mctrl_prev)); > + > if (istat & AUART_INTR_CTSMIS) { > if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(s->gpios, > - UART_GPIO_CTS))) > + UART_GPIO_CTS)) > + && s->ms_irq_enabled) > uart_handle_cts_change(&s->port, > stat & AUART_STAT_CTS); > writel(AUART_INTR_CTSMIS, > @@ -774,6 +878,10 @@ static int mxs_auart_startup(struct uart_port *u) > */ > writel(AUART_LINECTRL_FEN, u->membase + AUART_LINECTRL_SET); > > + /* get initial status of modem lines */ > + mctrl_gpio_get(s->gpios, &s->mctrl_prev); > + > + s->ms_irq_enabled = false; > return 0; > } > > @@ -781,6 +889,8 @@ static void mxs_auart_shutdown(struct uart_port *u) > { > struct mxs_auart_port *s = to_auart_port(u); > > + mxs_auart_disable_ms(u); > + > if (auart_dma_enabled(s)) > mxs_auart_dma_exit(s); > > @@ -837,6 +947,7 @@ static struct uart_ops mxs_auart_ops = { > .start_tx = mxs_auart_start_tx, > .stop_tx = mxs_auart_stop_tx, > .stop_rx = mxs_auart_stop_rx, > + .enable_ms = mxs_auart_enable_ms, > .break_ctl = mxs_auart_break_ctl, > .set_mctrl = mxs_auart_set_mctrl, > .get_mctrl = mxs_auart_get_mctrl, > @@ -1039,12 +1150,61 @@ static int serial_mxs_probe_dt(struct mxs_auart_port > *s, > > static int mxs_auart_init_gpios(struct mxs_auart_port *s, struct device *dev) > { > + enum mctrl_gpio_idx i; > + struct gpio_desc *gpiod; > + > s->gpios = mctrl_gpio_init(dev, 0); > if (IS_ERR_OR_NULL(s->gpios)) > return -1; > + > + for (i = 0; i < UART_GPIO_MAX; i++) { > + gpiod = mctrl_gpio_to_gpiod(s->gpios, i); > + if (gpiod && (gpiod_get_direction(gpiod) == GPIOF_DIR_IN)) > + s->gpio_irq[i] = gpiod_to_irq(gpiod); > + else > + s->gpio_irq[i] = -EINVAL; > + } > + > return 0; > } > > +static void mxs_auart_free_gpio_irq(struct mxs_auart_port *s) > +{ > + enum mctrl_gpio_idx i; > + > + for (i = 0; i < UART_GPIO_MAX; i++) > + if (s->gpio_irq[i] >= 0) > + free_irq(s->gpio_irq[i], s); > +} > + > +static int mxs_auart_request_gpio_irq(struct mxs_auart_port *s) > +{ > + int *irq = s->gpio_irq; > + enum mctrl_gpio_idx i; > + int err = 0; > + > + for (i = 0; (i < UART_GPIO_MAX) && !err; i++) { > + if (irq[i] < 0) > + continue; > + > + irq_set_status_flags(irq[i], IRQ_NOAUTOEN); > + err = request_irq(irq[i], mxs_auart_irq_handle, > + IRQ_TYPE_EDGE_BOTH, dev_name(s->dev), s); > + if (err) > + dev_err(s->dev, "%s - Can't get %d irq\n", > + __func__, irq[i]); > + } > + > + /* > + * If something went wrong, rollback. > + */ > + while (err && (--i >= 0)) > + if (irq[i] >= 0) > + free_irq(irq[i], s); > + > + return err; > +} > + > static int mxs_auart_probe(struct platform_device *pdev) > { > const struct of_device_id *of_id = > @@ -1092,6 +1252,8 @@ static int mxs_auart_probe(struct platform_device *pdev) > s->port.type = PORT_IMX; > s->port.dev = s->dev = &pdev->dev; > > + s->mctrl_prev = 0; > + > s->irq = platform_get_irq(pdev, 0); > s->port.irq = s->irq; > ret = request_irq(s->irq, mxs_auart_irq_handle, 0, > dev_name(&pdev->dev), s); > @@ -1105,13 +1267,20 @@ static int mxs_auart_probe(struct platform_device > *pdev) > dev_err(&pdev->dev, "%s", > "Failed to initialize GPIOs. The serial port may not > work as expected"); > > + /* > + * Get the GPIO lines IRQ > + */ > + ret = mxs_auart_request_gpio_irq(s); > + if (ret) > + goto out_free_irq; > + > auart_port[s->port.line] = s; > > mxs_auart_reset(&s->port); > > ret = uart_add_one_port(&auart_driver, &s->port); > if (ret) > - goto out_free_irq; > + goto out_free_gpio_irq; > > version = readl(s->port.membase + AUART_VERSION); > dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n", > @@ -1120,6 +1289,8 @@ static int mxs_auart_probe(struct platform_device *pdev) > > return 0; > > +out_free_gpio_irq: > + mxs_auart_free_gpio_irq(s); > out_free_irq: > auart_port[pdev->id] = NULL; > free_irq(s->irq, s); > @@ -1139,6 +1310,7 @@ static int mxs_auart_remove(struct platform_device > *pdev) > > auart_port[pdev->id] = NULL; > > + mxs_auart_free_gpio_irq(s); > clk_put(s->clk); > free_irq(s->irq, s); > kfree(s); > Seems also ok. Janusz, will you provide a patch to complete {en,dis}able_ms functions for non-gpio ?
Reviewed-by: Richard Genoud <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
