From ab5e4e4108ca5d8326cb6b4b3a21b096a002f68f Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Tue, 13 May 2014 20:20:45 +0200 Subject: [PATCH] tty/serial: at91: add interrupts for modem control lines Handle CTS/DSR/RI/DCD GPIO interrupts in atmel_serial. Signed-off-by: Richard Genoud Acked-by: Greg Kroah-Hartman Acked-by: Nicolas Ferre Signed-off-by: Greg Kroah-Hartman --- 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 43ca659c1d4b..3fceae099c44 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -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; + + 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 @@ -1590,6 +1683,13 @@ static int atmel_startup(struct uart_port *port) return retval; } + /* + * Get the GPIO lines IRQ + */ + retval = atmel_request_gpio_irq(port); + if (retval) + goto free_irq; + /* * Initialize DMA (if necessary) */ @@ -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; }