[PATCH RESEND 5/5] tty/serial: at91: add interrupts for modem control lines
Peter Hurley
peter at hurleysoftware.com
Sun Aug 10 12:33:12 PDT 2014
Hi Richard,
On 05/13/2014 02:20 PM, Richard Genoud wrote:
> Handle CTS/DSR/RI/DCD GPIO interrupts in atmel_serial.
>
> Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
> Acked-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Acked-by: Nicolas Ferre <nicolas.ferre at atmel.com>
> ---
> drivers/tty/serial/atmel_serial.c | 125 ++++++++++++++++++++++++++++++++++++-
> 1 file changed, 122 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index 43ca659..3fceae0 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -45,6 +45,7 @@
> #include <linux/gpio.h>
> #include <linux/gpio/consumer.h>
> #include <linux/err.h>
> +#include <linux/irq.h>
>
> #include <asm/io.h>
> #include <asm/ioctls.h>
> @@ -167,7 +168,9 @@ struct atmel_uart_port {
>
> struct serial_rs485 rs485; /* rs485 settings */
> struct mctrl_gpios *gpios;
> + int gpio_irq[UART_GPIO_MAX];
> unsigned int tx_done_mask;
> + bool ms_irq_enabled;
> bool is_usart; /* usart or uart */
> struct timer_list uart_timer; /* uart timer */
> int (*prepare_rx)(struct uart_port *port);
> @@ -489,8 +492,38 @@ static void atmel_stop_rx(struct uart_port *port)
> */
> static void atmel_enable_ms(struct uart_port *port)
> {
> - UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC
> - | ATMEL_US_DCDIC | ATMEL_US_CTSIC);
> + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> + uint32_t ier = 0;
> +
> + /*
> + * Interrupt should not be enabled twice
> + */
> + if (atmel_port->ms_irq_enabled)
> + return;
> +
> + atmel_port->ms_irq_enabled = true;
> +
> + if (atmel_port->gpio_irq[UART_GPIO_CTS] >= 0)
> + enable_irq(atmel_port->gpio_irq[UART_GPIO_CTS]);
> + else
> + ier |= ATMEL_US_CTSIC;
> +
> + if (atmel_port->gpio_irq[UART_GPIO_DSR] >= 0)
> + enable_irq(atmel_port->gpio_irq[UART_GPIO_DSR]);
> + else
> + ier |= ATMEL_US_DSRIC;
> +
> + if (atmel_port->gpio_irq[UART_GPIO_RI] >= 0)
> + enable_irq(atmel_port->gpio_irq[UART_GPIO_RI]);
> + else
> + ier |= ATMEL_US_RIIC;
> +
> + if (atmel_port->gpio_irq[UART_GPIO_DCD] >= 0)
> + enable_irq(atmel_port->gpio_irq[UART_GPIO_DCD]);
> + else
> + ier |= ATMEL_US_DCDIC;
Where are these gpio irqs disabled if !UART_ENABLE_MS()?
> +
> + UART_PUT_IER(port, ier);
> }
>
> /*
> @@ -1079,11 +1112,31 @@ atmel_handle_status(struct uart_port *port, unsigned int pending,
> static irqreturn_t atmel_interrupt(int irq, void *dev_id)
> {
> struct uart_port *port = dev_id;
> + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> unsigned int status, pending, pass_counter = 0;
> + bool gpio_handled = false;
>
> do {
> status = atmel_get_lines_status(port);
> pending = status & UART_GET_IMR(port);
> + if (!gpio_handled) {
> + /*
> + * Dealing with GPIO interrupt
> + */
> + if (irq == atmel_port->gpio_irq[UART_GPIO_CTS])
> + pending |= ATMEL_US_CTSIC;
> +
> + if (irq == atmel_port->gpio_irq[UART_GPIO_DSR])
> + pending |= ATMEL_US_DSRIC;
> +
> + if (irq == atmel_port->gpio_irq[UART_GPIO_RI])
> + pending |= ATMEL_US_RIIC;
> +
> + if (irq == atmel_port->gpio_irq[UART_GPIO_DCD])
> + pending |= ATMEL_US_DCDIC;
> +
> + gpio_handled = true;
> + }
> if (!pending)
> break;
>
> @@ -1563,6 +1616,45 @@ static void atmel_get_ip_name(struct uart_port *port)
> }
> }
>
> +static void atmel_free_gpio_irq(struct uart_port *port)
> +{
> + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> + enum mctrl_gpio_idx i;
> +
> + for (i = 0; i < UART_GPIO_MAX; i++)
> + if (atmel_port->gpio_irq[i] >= 0)
> + free_irq(atmel_port->gpio_irq[i], port);
> +}
> +
> +static int atmel_request_gpio_irq(struct uart_port *port)
> +{
> + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> + int *irq = atmel_port->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], atmel_interrupt, IRQ_TYPE_EDGE_BOTH,
> + "atmel_serial", port);
> + if (err)
> + dev_err(port->dev, "atmel_startup - Can't get %d irq\n",
> + irq[i]);
> + }
> +
> + /*
> + * If something went wrong, rollback.
> + */
> + while (err && (--i >= 0))
> + if (irq[i] >= 0)
> + free_irq(irq[i], port);
> +
> + return err;
> +}
> +
> /*
> * Perform initialization and enable port for reception
> */
> @@ -1579,6 +1671,7 @@ static int atmel_startup(struct uart_port *port)
> * handle an unexpected interrupt
> */
> UART_PUT_IDR(port, -1);
> + atmel_port->ms_irq_enabled = false;
>
> /*
> * Allocate the IRQ
> @@ -1591,6 +1684,13 @@ static int atmel_startup(struct uart_port *port)
> }
>
> /*
> + * Get the GPIO lines IRQ
> + */
> + retval = atmel_request_gpio_irq(port);
> + if (retval)
> + goto free_irq;
> +
> + /*
> * Initialize DMA (if necessary)
> */
> atmel_init_property(atmel_port, pdev);
> @@ -1654,6 +1754,11 @@ static int atmel_startup(struct uart_port *port)
> }
>
> return 0;
> +
> +free_irq:
> + free_irq(port->irq, port);
> +
> + return retval;
> }
>
> /*
> @@ -1701,9 +1806,12 @@ static void atmel_shutdown(struct uart_port *port)
> atmel_port->rx_ring.tail = 0;
>
> /*
> - * Free the interrupt
> + * Free the interrupts
> */
> free_irq(port->irq, port);
> + atmel_free_gpio_irq(port);
> +
> + atmel_port->ms_irq_enabled = false;
> }
>
> /*
> @@ -2366,10 +2474,21 @@ static int atmel_serial_resume(struct platform_device *pdev)
>
> static int atmel_init_gpios(struct atmel_uart_port *p, struct device *dev)
> {
> + enum mctrl_gpio_idx i;
> + struct gpio_desc *gpiod;
> +
> p->gpios = mctrl_gpio_init(dev, 0);
> if (IS_ERR_OR_NULL(p->gpios))
> return -1;
>
> + for (i = 0; i < UART_GPIO_MAX; i++) {
> + gpiod = mctrl_gpio_to_gpiod(p->gpios, i);
> + if (gpiod && (gpiod_get_direction(gpiod) == GPIOF_DIR_IN))
> + p->gpio_irq[i] = gpiod_to_irq(gpiod);
> + else
> + p->gpio_irq[i] = -EINVAL;
> + }
> +
> return 0;
> }
>
>
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