On 10/03/2014 17:45, Richard Genoud : > On sam9x5, dedicated CTS (and RTS) pins are unusable together with the > LCDC, the EMAC, or the MMC because they share the same line. > > Moreover, the USART controller doesn't handle DTR/DSR/DCD/RI signals, > so we have to control them via GPIO. > > This patch permits to use GPIOs to control the CTS/RTS/DTR/DSR/DCD/RI > signals. > > Signed-off-by: Richard Genoud <richard.genoud@xxxxxxxxx> Good for me: Greg are you okay to take the at91 bits included in this patch? Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx> > --- > .../devicetree/bindings/serial/atmel-usart.txt | 12 ++- > arch/arm/mach-at91/at91rm9200_devices.c | 16 ++-- > arch/arm/mach-at91/at91sam9260_devices.c | 7 -- > arch/arm/mach-at91/at91sam9261_devices.c | 4 - > arch/arm/mach-at91/at91sam9263_devices.c | 4 - > arch/arm/mach-at91/at91sam9g45_devices.c | 5 - > arch/arm/mach-at91/at91sam9rl_devices.c | 5 - > drivers/tty/serial/Kconfig | 1 + > drivers/tty/serial/atmel_serial.c | 105 ++++++++++++++------- > include/linux/platform_data/atmel.h | 1 - > 10 files changed, 90 insertions(+), 70 deletions(-) > > diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt > index 17c1042b2df8..a6391e70a8fd 100644 > --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt > +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt > @@ -13,8 +13,9 @@ 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. > +- {rts,cts,dtr,dsr,rng,dcd}-gpios: specify a GPIO for RTS/CTS/DTR/DSR/RI/DCD line respectively. > + It will use specified PIO instead of the peripheral function pin for the USART 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. > @@ -35,7 +36,12 @@ Example: > clock-names = "usart"; > atmel,use-dma-rx; > atmel,use-dma-tx; > - rts-gpios = <&pioD 15 0>; > + rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>; > + cts-gpios = <&pioD 16 GPIO_ACTIVE_LOW>; > + dtr-gpios = <&pioD 17 GPIO_ACTIVE_LOW>; > + dsr-gpios = <&pioD 18 GPIO_ACTIVE_LOW>; > + dcd-gpios = <&pioD 20 GPIO_ACTIVE_LOW>; > + rng-gpios = <&pioD 19 GPIO_ACTIVE_LOW>; > }; > > - use DMA: > diff --git a/arch/arm/mach-at91/at91rm9200_devices.c b/arch/arm/mach-at91/at91rm9200_devices.c > index f3f19f21352a..291a90a5b1d4 100644 > --- a/arch/arm/mach-at91/at91rm9200_devices.c > +++ b/arch/arm/mach-at91/at91rm9200_devices.c > @@ -15,6 +15,7 @@ > > #include <linux/dma-mapping.h> > #include <linux/gpio.h> > +#include <linux/gpio/driver.h> > #include <linux/platform_device.h> > #include <linux/i2c-gpio.h> > > @@ -923,7 +924,6 @@ 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); > @@ -962,7 +962,14 @@ static struct resource uart0_resources[] = { > static struct atmel_uart_data uart0_data = { > .use_dma_tx = 1, > .use_dma_rx = 1, > - .rts_gpio = -EINVAL, > +}; > + > +static struct gpiod_lookup_table uart0_gpios_table = { > + .dev_id = "atmel_usart", > + .table = { > + GPIO_LOOKUP("pioA", 21, "rts", GPIO_ACTIVE_LOW), > + { }, > + }, > }; > > static u64 uart0_dmamask = DMA_BIT_MASK(32); > @@ -993,7 +1000,7 @@ static inline void configure_usart0_pins(unsigned pins) > * We need to drive the pin manually. The serial driver will driver > * this to high when initializing. > */ > - uart0_data.rts_gpio = AT91_PIN_PA21; > + gpiod_add_lookup_table(&uart0_gpios_table); > } > } > > @@ -1013,7 +1020,6 @@ 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); > @@ -1065,7 +1071,6 @@ 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); > @@ -1109,7 +1114,6 @@ 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 2ae7715f1309..a1b989eac8b8 100644 > --- a/arch/arm/mach-at91/at91sam9260_devices.c > +++ b/arch/arm/mach-at91/at91sam9260_devices.c > @@ -820,7 +820,6 @@ 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); > @@ -859,7 +858,6 @@ 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); > @@ -911,7 +909,6 @@ 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); > @@ -955,7 +952,6 @@ 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); > @@ -999,7 +995,6 @@ 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); > @@ -1043,7 +1038,6 @@ 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); > @@ -1082,7 +1076,6 @@ 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 80e35895d28f..b5f7a7226ff8 100644 > --- a/arch/arm/mach-at91/at91sam9261_devices.c > +++ b/arch/arm/mach-at91/at91sam9261_devices.c > @@ -881,7 +881,6 @@ 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); > @@ -920,7 +919,6 @@ 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); > @@ -964,7 +962,6 @@ 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); > @@ -1008,7 +1005,6 @@ 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 43d53d6156dd..39803c3296b2 100644 > --- a/arch/arm/mach-at91/at91sam9263_devices.c > +++ b/arch/arm/mach-at91/at91sam9263_devices.c > @@ -1325,7 +1325,6 @@ 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); > @@ -1364,7 +1363,6 @@ 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); > @@ -1408,7 +1406,6 @@ 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); > @@ -1452,7 +1449,6 @@ 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 77b04c2edd78..4e53d8d9737b 100644 > --- a/arch/arm/mach-at91/at91sam9g45_devices.c > +++ b/arch/arm/mach-at91/at91sam9g45_devices.c > @@ -1588,7 +1588,6 @@ 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); > @@ -1627,7 +1626,6 @@ 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); > @@ -1671,7 +1669,6 @@ 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); > @@ -1715,7 +1712,6 @@ 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); > @@ -1759,7 +1755,6 @@ 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 428fc412aaf1..f75985062913 100644 > --- a/arch/arm/mach-at91/at91sam9rl_devices.c > +++ b/arch/arm/mach-at91/at91sam9rl_devices.c > @@ -957,7 +957,6 @@ 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); > @@ -996,7 +995,6 @@ 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); > @@ -1048,7 +1046,6 @@ 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); > @@ -1092,7 +1089,6 @@ 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); > @@ -1136,7 +1132,6 @@ 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/Kconfig b/drivers/tty/serial/Kconfig > index 7e8f15cfb8d0..f4e20410a138 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -97,6 +97,7 @@ config SERIAL_ATMEL > bool "AT91 / AT32 on-chip serial port support" > depends on ARCH_AT91 || AVR32 > select SERIAL_CORE > + select SERIAL_MCTRL_GPIO > help > This enables the driver for the on-chip UARTs of the Atmel > AT91 and AT32 processors. > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 53eeea13ff16..43ca659c1d4b 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -43,6 +43,8 @@ > #include <linux/platform_data/atmel.h> > #include <linux/timer.h> > #include <linux/gpio.h> > +#include <linux/gpio/consumer.h> > +#include <linux/err.h> > > #include <asm/io.h> > #include <asm/ioctls.h> > @@ -57,6 +59,8 @@ > > #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); > > @@ -162,7 +166,7 @@ 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; > unsigned int tx_done_mask; > bool is_usart; /* usart or uart */ > struct timer_list uart_timer; /* uart timer */ > @@ -237,6 +241,50 @@ 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 +344,6 @@ 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 +356,8 @@ 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 +385,8 @@ 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 +402,7 @@ 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); > } > > /* > @@ -1042,7 +1082,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id) > unsigned int status, pending, pass_counter = 0; > > do { > - status = UART_GET_CSR(port); > + status = atmel_get_lines_status(port); > pending = status & UART_GET_IMR(port); > if (!pending) > break; > @@ -1568,7 +1608,7 @@ 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; > > /* > @@ -2324,6 +2364,15 @@ 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) > +{ > + p->gpios = mctrl_gpio_init(dev, 0); > + if (IS_ERR_OR_NULL(p->gpios)) > + return -1; > + > + return 0; > +} > + > static int atmel_serial_probe(struct platform_device *pdev) > { > struct atmel_uart_port *port; > @@ -2359,25 +2408,11 @@ 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) > diff --git a/include/linux/platform_data/atmel.h b/include/linux/platform_data/atmel.h > index e26b0c14edea..cea9f70133c5 100644 > --- a/include/linux/platform_data/atmel.h > +++ b/include/linux/platform_data/atmel.h > @@ -84,7 +84,6 @@ 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 */ > -- Nicolas Ferre -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html