From: Linus Walleij Date: Thu, 7 Nov 2013 09:25:55 +0000 (+0100) Subject: ARM/serial: at91: switch atmel serial to use gpiolib X-Git-Tag: next-20140306~110^2~23^2^2~13 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=354e57f3a0a26120af3bcd6c92c355ad00a057c1;p=karo-tx-linux.git ARM/serial: at91: switch atmel serial to use gpiolib This passes the errata fix using a GPIO to control the RTS pin on one of the AT91 chips to use gpiolib instead of the AT91-specific interfaces. Also remove the reliance on compile-time #defines and the cpu_* check and rely on the platform passing down the proper GPIO pin through platform data. This is a prerequisite for getting rid of the local GPIO implementation in the AT91 platform and move toward multiplatform. The patch also adds device tree support for getting the RTS GPIO pin from the device tree on DT boot paths. Signed-off-by: Nicolas Ferre Acked-by: Jean-Christophe PLAGNIOL-VILLARD Signed-off-by: Linus Walleij Acked-by: Greg Kroah-Hartman Signed-off-by: Uwe Kleine-König --- diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt index 2191dcb9f1da..3adc61c2e4ca 100644 --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt @@ -10,6 +10,8 @@ Required properties: Optional properties: - atmel,use-dma-rx: use of PDC or DMA for receiving data - atmel,use-dma-tx: use of PDC or DMA for transmitting data +- rts-gpios: specify a GPIO for RTS line. It will use specified PIO instead of the peripheral + function pin for the USART RTS feature. If unsure, don't specify this property. - add dma bindings for dma transfer: - dmas: DMA specifier, consisting of a phandle to DMA controller node, memory peripheral interface and USART DMA channel ID, FIFO configuration. @@ -28,6 +30,7 @@ Example: interrupts = <7>; atmel,use-dma-rx; atmel,use-dma-tx; + rts-gpios = <&pioD 15 0>; }; - use DMA: diff --git a/arch/arm/mach-at91/at91rm9200_devices.c b/arch/arm/mach-at91/at91rm9200_devices.c index 3ebc9792560c..605add05af7e 100644 --- a/arch/arm/mach-at91/at91rm9200_devices.c +++ b/arch/arm/mach-at91/at91rm9200_devices.c @@ -922,6 +922,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, /* DBGU not capable of receive DMA */ + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -960,6 +961,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -987,9 +989,10 @@ static inline void configure_usart0_pins(unsigned pins) if (pins & ATMEL_UART_RTS) { /* * AT91RM9200 Errata #39 - RTS0 is not internally connected to PA21. - * We need to drive the pin manually. Default is off (RTS is active low). + * We need to drive the pin manually. The serial driver will driver + * this to high when initializing. */ - at91_set_gpio_output(AT91_PIN_PA21, 1); + uart0_data.rts_gpio = AT91_PIN_PA21; } } @@ -1009,6 +1012,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -1060,6 +1064,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); @@ -1103,6 +1108,7 @@ static struct resource uart3_resources[] = { static struct atmel_uart_data uart3_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart3_dmamask = DMA_BIT_MASK(32); diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c index eda8d1679d40..b52527c78b12 100644 --- a/arch/arm/mach-at91/at91sam9260_devices.c +++ b/arch/arm/mach-at91/at91sam9260_devices.c @@ -819,6 +819,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, /* DBGU not capable of receive DMA */ + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -857,6 +858,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -908,6 +910,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -951,6 +954,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); @@ -994,6 +998,7 @@ static struct resource uart3_resources[] = { static struct atmel_uart_data uart3_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart3_dmamask = DMA_BIT_MASK(32); @@ -1037,6 +1042,7 @@ static struct resource uart4_resources[] = { static struct atmel_uart_data uart4_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart4_dmamask = DMA_BIT_MASK(32); @@ -1075,6 +1081,7 @@ static struct resource uart5_resources[] = { static struct atmel_uart_data uart5_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart5_dmamask = DMA_BIT_MASK(32); diff --git a/arch/arm/mach-at91/at91sam9261_devices.c b/arch/arm/mach-at91/at91sam9261_devices.c index b2a34740146a..6c1a2ecc306f 100644 --- a/arch/arm/mach-at91/at91sam9261_devices.c +++ b/arch/arm/mach-at91/at91sam9261_devices.c @@ -880,6 +880,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, /* DBGU not capable of receive DMA */ + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -918,6 +919,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -961,6 +963,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -1004,6 +1007,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); diff --git a/arch/arm/mach-at91/at91sam9263_devices.c b/arch/arm/mach-at91/at91sam9263_devices.c index 4aeadddbc181..97cc2a0d6f90 100644 --- a/arch/arm/mach-at91/at91sam9263_devices.c +++ b/arch/arm/mach-at91/at91sam9263_devices.c @@ -1324,6 +1324,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, /* DBGU not capable of receive DMA */ + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -1362,6 +1363,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -1405,6 +1407,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -1448,6 +1451,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c index cb36fa872d30..c10149588e21 100644 --- a/arch/arm/mach-at91/at91sam9g45_devices.c +++ b/arch/arm/mach-at91/at91sam9g45_devices.c @@ -1587,6 +1587,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -1625,6 +1626,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -1668,6 +1670,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -1711,6 +1714,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); @@ -1754,6 +1758,7 @@ static struct resource uart3_resources[] = { static struct atmel_uart_data uart3_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart3_dmamask = DMA_BIT_MASK(32); diff --git a/arch/arm/mach-at91/at91sam9rl_devices.c b/arch/arm/mach-at91/at91sam9rl_devices.c index a698bdab2cce..4120af972b61 100644 --- a/arch/arm/mach-at91/at91sam9rl_devices.c +++ b/arch/arm/mach-at91/at91sam9rl_devices.c @@ -956,6 +956,7 @@ static struct resource dbgu_resources[] = { static struct atmel_uart_data dbgu_data = { .use_dma_tx = 0, .use_dma_rx = 0, /* DBGU not capable of receive DMA */ + .rts_gpio = -EINVAL, }; static u64 dbgu_dmamask = DMA_BIT_MASK(32); @@ -994,6 +995,7 @@ static struct resource uart0_resources[] = { static struct atmel_uart_data uart0_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart0_dmamask = DMA_BIT_MASK(32); @@ -1045,6 +1047,7 @@ static struct resource uart1_resources[] = { static struct atmel_uart_data uart1_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart1_dmamask = DMA_BIT_MASK(32); @@ -1088,6 +1091,7 @@ static struct resource uart2_resources[] = { static struct atmel_uart_data uart2_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart2_dmamask = DMA_BIT_MASK(32); @@ -1131,6 +1135,7 @@ static struct resource uart3_resources[] = { static struct atmel_uart_data uart3_data = { .use_dma_tx = 1, .use_dma_rx = 1, + .rts_gpio = -EINVAL, }; static u64 uart3_dmamask = DMA_BIT_MASK(32); diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index c7d99af46a96..40d6c9b0d98b 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -35,21 +35,18 @@ #include #include #include +#include #include #include #include #include #include #include +#include #include #include -#ifdef CONFIG_ARM -#include -#include -#endif - #define PDC_BUFFER_SIZE 512 /* Revisit: We should calculate this based on the actual port settings */ #define PDC_RX_TIMEOUT (3 * 10) /* 3 bytes */ @@ -168,6 +165,7 @@ struct atmel_uart_port { struct circ_buf rx_ring; struct serial_rs485 rs485; /* rs485 settings */ + int rts_gpio; /* optional RTS GPIO */ unsigned int tx_done_mask; bool is_usart; /* usart or uart */ struct timer_list uart_timer; /* uart timer */ @@ -301,20 +299,16 @@ 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); -#ifdef CONFIG_ARCH_AT91RM9200 - if (cpu_is_at91rm9200()) { - /* - * AT91RM9200 Errata #39: RTS0 is not internally connected - * to PA21. We need to drive the pin manually. - */ - if (port->mapbase == AT91RM9200_BASE_US0) { - if (mctrl & TIOCM_RTS) - at91_set_gpio_value(AT91_PIN_PA21, 0); - else - at91_set_gpio_value(AT91_PIN_PA21, 1); - } + /* + * 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); } -#endif if (mctrl & TIOCM_RTS) control |= ATMEL_US_RTSEN; @@ -2379,6 +2373,25 @@ 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_port(port, pdev); if (ret) diff --git a/include/linux/platform_data/atmel.h b/include/linux/platform_data/atmel.h index cea9f70133c5..e26b0c14edea 100644 --- a/include/linux/platform_data/atmel.h +++ b/include/linux/platform_data/atmel.h @@ -84,6 +84,7 @@ struct atmel_uart_data { short use_dma_rx; /* use receive DMA? */ void __iomem *regs; /* virt. base address, if any */ struct serial_rs485 rs485; /* rs485 settings */ + int rts_gpio; /* optional RTS GPIO */ }; /* Touchscreen Controller */