diff options
Diffstat (limited to 'drivers/tty/serial/atmel_serial.c')
| -rw-r--r-- | drivers/tty/serial/atmel_serial.c | 230 |
1 files changed, 192 insertions, 38 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 53eeea13ff1..3fceae099c4 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -43,6 +43,9 @@ #include <linux/platform_data/atmel.h> #include <linux/timer.h> #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> @@ -57,6 +60,8 @@ #include <linux/serial_core.h> +#include "serial_mctrl_gpio.h" + static void atmel_start_rx(struct uart_port *port); static void atmel_stop_rx(struct uart_port *port); @@ -162,8 +167,10 @@ struct atmel_uart_port { struct circ_buf rx_ring; struct serial_rs485 rs485; /* rs485 settings */ - int rts_gpio; /* optional RTS GPIO */ + 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); @@ -237,6 +244,50 @@ static bool atmel_use_dma_rx(struct uart_port *port) return atmel_port->use_dma_rx; } +static unsigned int atmel_get_lines_status(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + unsigned int status, ret = 0; + + status = UART_GET_CSR(port); + + mctrl_gpio_get(atmel_port->gpios, &ret); + + if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios, + UART_GPIO_CTS))) { + if (ret & TIOCM_CTS) + status &= ~ATMEL_US_CTS; + else + status |= ATMEL_US_CTS; + } + + if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios, + UART_GPIO_DSR))) { + if (ret & TIOCM_DSR) + status &= ~ATMEL_US_DSR; + else + status |= ATMEL_US_DSR; + } + + if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios, + UART_GPIO_RI))) { + if (ret & TIOCM_RI) + status &= ~ATMEL_US_RI; + else + status |= ATMEL_US_RI; + } + + if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios, + UART_GPIO_DCD))) { + if (ret & TIOCM_CD) + status &= ~ATMEL_US_DCD; + else + status |= ATMEL_US_DCD; + } + + return status; +} + /* Enable or disable the rs485 support */ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf) { @@ -296,17 +347,6 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) unsigned int mode; struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); - /* - * AT91RM9200 Errata #39: RTS0 is not internally connected - * to PA21. We need to drive the pin as a GPIO. - */ - if (gpio_is_valid(atmel_port->rts_gpio)) { - if (mctrl & TIOCM_RTS) - gpio_set_value(atmel_port->rts_gpio, 0); - else - gpio_set_value(atmel_port->rts_gpio, 1); - } - if (mctrl & TIOCM_RTS) control |= ATMEL_US_RTSEN; else @@ -319,6 +359,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) UART_PUT_CR(port, control); + mctrl_gpio_set(atmel_port->gpios, mctrl); + /* Local loopback mode? */ mode = UART_GET_MR(port) & ~ATMEL_US_CHMODE; if (mctrl & TIOCM_LOOP) @@ -346,7 +388,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) */ static u_int atmel_get_mctrl(struct uart_port *port) { - unsigned int status, ret = 0; + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + unsigned int ret = 0, status; status = UART_GET_CSR(port); @@ -362,7 +405,7 @@ static u_int atmel_get_mctrl(struct uart_port *port) if (!(status & ATMEL_US_RI)) ret |= TIOCM_RI; - return ret; + return mctrl_gpio_get(atmel_port->gpios, &ret); } /* @@ -449,8 +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); } /* @@ -1039,11 +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 = UART_GET_CSR(port); + 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; @@ -1523,6 +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 */ @@ -1539,6 +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 @@ -1551,6 +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); @@ -1568,7 +1708,7 @@ static int atmel_startup(struct uart_port *port) } /* Save current CSR for comparison in atmel_tasklet_func() */ - atmel_port->irq_status_prev = UART_GET_CSR(port); + atmel_port->irq_status_prev = atmel_get_lines_status(port); atmel_port->irq_status = atmel_port->irq_status_prev; /* @@ -1614,6 +1754,11 @@ static int atmel_startup(struct uart_port *port) } return 0; + +free_irq: + free_irq(port->irq, port); + + return retval; } /* @@ -1661,9 +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; } /* @@ -2324,6 +2472,26 @@ static int atmel_serial_resume(struct platform_device *pdev) #define atmel_serial_resume NULL #endif +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; +} + static int atmel_serial_probe(struct platform_device *pdev) { struct atmel_uart_port *port; @@ -2359,25 +2527,11 @@ static int atmel_serial_probe(struct platform_device *pdev) port = &atmel_ports[ret]; port->backup_imr = 0; port->uart.line = ret; - port->rts_gpio = -EINVAL; /* Invalid, zero could be valid */ - if (pdata) - port->rts_gpio = pdata->rts_gpio; - else if (np) - port->rts_gpio = of_get_named_gpio(np, "rts-gpios", 0); - - if (gpio_is_valid(port->rts_gpio)) { - ret = devm_gpio_request(&pdev->dev, port->rts_gpio, "RTS"); - if (ret) { - dev_err(&pdev->dev, "error requesting RTS GPIO\n"); - goto err; - } - /* Default to 1 as RTS is active low */ - ret = gpio_direction_output(port->rts_gpio, 1); - if (ret) { - dev_err(&pdev->dev, "error setting up RTS GPIO\n"); - goto err; - } - } + + ret = atmel_init_gpios(port, &pdev->dev); + if (ret < 0) + dev_err(&pdev->dev, "%s", + "Failed to initialize GPIOs. The serial port may not work as expected"); ret = atmel_init_port(port, pdev); if (ret) |