From fcbee4d49f30eb0eaa83a62e6a3cab5a892ed93f Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Thu, 24 Apr 2014 15:54:44 +0900 Subject: serial: sh-sci: Add device tree support for r8a7779 According to the platform data for the legacy-C initialisation of sh-sci for the r8a7779 SoC and my own testing the SCIx_SH4_SCIF_REGTYPE bit of scscr needs to be set. Signed-off-by: Simon Horman Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/serial/renesas,sci-serial.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt index 53e6c175db6c..bba86de1a094 100644 --- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt +++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt @@ -12,6 +12,7 @@ Required properties: - "renesas,scifa-r8a7791" for R8A7791 (R-Car M2) SCIFA compatible UART. - "renesas,scifb-r8a7791" for R8A7791 (R-Car M2) SCIFB compatible UART. - "renesas,hscif-r8a7791" for R8A7791 (R-Car M2) HSCIF compatible UART. + - "renesas,scif-r8a7779" for R8A7779 (R-Car H1) SCIF compatible UART. - "renesas,scif" for generic SCIF compatible UART. - "renesas,scifa" for generic SCIFA compatible UART. - "renesas,scifb" for generic SCIFB compatible UART. -- cgit v1.2.3 From 0d3c673e7881e691991b2a4745bd4f149603baa2 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Fri, 18 Apr 2014 17:19:57 -0500 Subject: tty/serial: pl011: add generic earlycon support Add earlycon support for the pl011 serial port. This allows enabling the pl011 for console when early_params are processed. This is based on the arm64 earlyprintk support and is intended to replace it. Signed-off-by: Rob Herring Cc: Russell King Cc: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 7 +++++++ drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/amba-pl011.c | 30 +++++++++++++++++++++++++++++- 3 files changed, 37 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 43842177b771..2609ead7ff55 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -883,6 +883,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. which are not unmapped. earlycon= [KNL] Output early console device and options. + uart[8250],io,[,options] uart[8250],mmio,[,options] uart[8250],mmio32,[,options] @@ -892,6 +893,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. (mmio) or 32-bit (mmio32). The options are the same as for ttyS, above. + pl011, + Start an early, polled-mode console on a pl011 serial + port at the specified address. The pl011 serial port + must already be setup and configured. Options are not + yet supported. + earlyprintk= [X86,SH,BLACKFIN,ARM] earlyprintk=vga earlyprintk=efi diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 9fb6028ad900..4290d05875b1 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -60,6 +60,7 @@ config SERIAL_AMBA_PL011_CONSOLE bool "Support for console on AMBA serial port" depends on SERIAL_AMBA_PL011=y select SERIAL_CORE_CONSOLE + select SERIAL_EARLYCON ---help--- Say Y here if you wish to use an AMBA PrimeCell UART as the system console (the system console is the device which receives all kernel diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index dacf0a09ab24..ee3d80346780 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -303,7 +303,7 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port * /* Optionally make use of an RX channel as well */ chan = dma_request_slave_channel(dev, "rx"); - + if (!chan && plat->dma_rx_param) { chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param); @@ -2045,6 +2045,34 @@ static struct console amba_console = { }; #define AMBA_CONSOLE (&amba_console) + +static void pl011_putc(struct uart_port *port, int c) +{ + while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF) + ; + writeb(c, port->membase + UART01x_DR); + while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY) + ; +} + +static void pl011_early_write(struct console *con, const char *s, unsigned n) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, n, pl011_putc); +} + +static int __init pl011_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = pl011_early_write; + return 0; +} +EARLYCON_DECLARE(pl011, pl011_early_console_setup); + #else #define AMBA_CONSOLE NULL #endif -- cgit v1.2.3 From d50d7269ebcb438afa346cdffce0f4e2a1b9e831 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Fri, 18 Apr 2014 17:19:58 -0500 Subject: tty/serial: add arm/arm64 semihosting earlycon Add earlycon support for the arm/arm64 semihosting debug serial interface. This allows enabling a debug console when early_params are processed. This is based on the arm64 earlyprintk smh support and is intended to replace it. Signed-off-by: Rob Herring Cc: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 2 + drivers/tty/serial/Kconfig | 10 +++++ drivers/tty/serial/Makefile | 1 + drivers/tty/serial/earlycon-arm-semihost.c | 61 ++++++++++++++++++++++++++++++ 4 files changed, 74 insertions(+) create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 2609ead7ff55..4946d8e58d53 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -899,6 +899,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. must already be setup and configured. Options are not yet supported. + smh Use ARM semihosting calls for early console. + earlyprintk= [X86,SH,BLACKFIN,ARM] earlyprintk=vga earlyprintk=efi diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 4290d05875b1..988fa2b6243b 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -73,6 +73,16 @@ config SERIAL_AMBA_PL011_CONSOLE your boot loader (lilo or loadlin) about how to pass options to the kernel at boot time.) +config SERIAL_EARLYCON_ARM_SEMIHOST + bool "Early console using ARM semihosting" + depends on ARM64 || ARM + select SERIAL_EARLYCON + help + Support for early debug console using ARM semihosting. This enables + the console before standard serial driver is probed. This is enabled + with "earlycon=smh" on the kernel command line. The console is + enabled when early_param is processed. + config SERIAL_SB1250_DUART tristate "BCM1xxx on-chip DUART serial support" depends on SIBYTE_SB1xxx_SOC=y diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index 28048178f308..3a5be4633333 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_SERIAL_CORE) += serial_core.o obj-$(CONFIG_SERIAL_21285) += 21285.o obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o +obj-$(CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST) += earlycon-arm-semihost.o # These Sparc drivers have to appear before others such as 8250 # which share ttySx minor node space. Otherwise console device diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c new file mode 100644 index 000000000000..383db10fbb49 --- /dev/null +++ b/drivers/tty/serial/earlycon-arm-semihost.c @@ -0,0 +1,61 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * Author: Marc Zyngier + * + * Adapted for ARM and earlycon: + * Copyright (C) 2014 Linaro Ltd. + * Author: Rob Herring + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +#include +#include +#include +#include + +#ifdef CONFIG_THUMB2_KERNEL +#define SEMIHOST_SWI "0xab" +#else +#define SEMIHOST_SWI "0x123456" +#endif + +/* + * Semihosting-based debug console + */ +static void smh_putc(struct uart_port *port, int c) +{ +#ifdef CONFIG_ARM64 + asm volatile("mov x1, %0\n" + "mov x0, #3\n" + "hlt 0xf000\n" + : : "r" (&c) : "x0", "x1", "memory"); +#else + asm volatile("mov r1, %0\n" + "mov r0, #3\n" + "svc " SEMIHOST_SWI "\n" + : : "r" (&c) : "r0", "r1", "memory"); +#endif +} + +static void smh_write(struct console *con, const char *s, unsigned n) +{ + struct earlycon_device *dev = con->data; + uart_console_write(&dev->port, s, n, smh_putc); +} + +int __init early_smh_setup(struct earlycon_device *device, const char *opt) +{ + device->con->write = smh_write; + return 0; +} +EARLYCON_DECLARE(smh, early_smh_setup); -- cgit v1.2.3 From 2aafb3864b9fa5ce83250537d940f973ef37b8dc Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 24 Apr 2014 19:26:16 -0700 Subject: Revert "serial: sh-sci: Add device tree support for r8a7779" This reverts commit fcbee4d49f30eb0eaa83a62e6a3cab5a892ed93f. It wasn't quite ready to go in yet, sorry about that. Cc: Simon Horman Cc: Laurent Pinchart Signed-off-by: Greg Kroah-Hartman --- .../devicetree/bindings/serial/renesas,sci-serial.txt | 1 - drivers/tty/serial/sh-sci.c | 10 +--------- 2 files changed, 1 insertion(+), 10 deletions(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt index bba86de1a094..53e6c175db6c 100644 --- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt +++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt @@ -12,7 +12,6 @@ Required properties: - "renesas,scifa-r8a7791" for R8A7791 (R-Car M2) SCIFA compatible UART. - "renesas,scifb-r8a7791" for R8A7791 (R-Car M2) SCIFB compatible UART. - "renesas,hscif-r8a7791" for R8A7791 (R-Car M2) HSCIF compatible UART. - - "renesas,scif-r8a7779" for R8A7779 (R-Car H1) SCIF compatible UART. - "renesas,scif" for generic SCIF compatible UART. - "renesas,scifa" for generic SCIFA compatible UART. - "renesas,scifb" for generic SCIFB compatible UART. diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 3b5d2f679946..88236da0ddf7 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -2419,7 +2419,6 @@ static int sci_remove(struct platform_device *dev) struct sci_port_info { unsigned int type; unsigned int regtype; - unsigned int scscr_extra; }; static const struct of_device_id of_sci_match[] = { @@ -2429,13 +2428,6 @@ static const struct of_device_id of_sci_match[] = { .type = PORT_SCIF, .regtype = SCIx_SH4_SCIF_REGTYPE, }, - }, { - .compatible = "renesas,scif-r8a7779", - .data = (void *)&(const struct sci_port_info) { - .type = PORT_SCIF, - .regtype = SCIx_SH4_SCIF_REGTYPE, - .scscr_extra = SCSCR_CKE1, - }, }, { .compatible = "renesas,scifa", .data = &(const struct sci_port_info) { @@ -2496,7 +2488,7 @@ sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id) p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; p->type = info->type; p->regtype = info->regtype; - p->scscr = SCSCR_RE | SCSCR_TE | info->scscr_extra; + p->scscr = SCSCR_RE | SCSCR_TE; return p; } -- cgit v1.2.3 From 89054c7b5bb83050fb783efc5a528eebb42c0925 Mon Sep 17 00:00:00 2001 From: Jon Ringle Date: Thu, 24 Apr 2014 20:56:07 -0400 Subject: serial: sc16is7xx: Add bindings documentation for the SC16IS7XX UARTs This patch adds the devicetree documentation for the NXP SC16IS7XX UARTs. Signed-off-by: Jon Ringle Signed-off-by: Greg Kroah-Hartman --- .../devicetree/bindings/serial/nxp,sc16is7xx.txt | 33 ++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt b/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt new file mode 100644 index 000000000000..246c795668dc --- /dev/null +++ b/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt @@ -0,0 +1,33 @@ +* NXP SC16IS7xx advanced Universal Asynchronous Receiver-Transmitter (UART) + +Required properties: +- compatible: Should be one of the following: + - "nxp,sc16is740" for NXP SC16IS740, + - "nxp,sc16is741" for NXP SC16IS741, + - "nxp,sc16is750" for NXP SC16IS750, + - "nxp,sc16is752" for NXP SC16IS752, + - "nxp,sc16is760" for NXP SC16IS760, + - "nxp,sc16is762" for NXP SC16IS762. +- reg: I2C address of the SC16IS7xx device. +- interrupt-parent: The phandle for the interrupt controller that + services interrupts for this IC. +- interrupts: Should contain the UART interrupt +- clocks: Reference to the IC source clock. + +Optional properties: +- gpio-controller: Marks the device node as a GPIO controller. +- #gpio-cells: Should be two. The first cell is the GPIO number and + the second cell is used to specify the GPIO polarity: + 0 = active high, + 1 = active low. + +Example: + sc16is750: sc16is750@51 { + compatible = "nxp,sc16is750"; + reg = <0x51>; + clocks = <&clk20m>; + interrupt-parent = <&gpio3>; + interrupts = <7 IRQ_TYPE_EDGE_FALLING>; + gpio-controller; + #gpio-cells = <2>; + }; -- cgit v1.2.3 From 81bd1eb7af751666ace2f1dadb0b0101401807cd Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Thu, 15 May 2014 20:00:58 +0900 Subject: serial: sh-sci: Add device tree support for r8a7779 Simply document a new compat string. There appears to be no need for a driver updates. Acked-by: Laurent Pinchart Signed-off-by: Simon Horman Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/serial/renesas,sci-serial.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt index 53e6c175db6c..64fd7dec1bbc 100644 --- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt +++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt @@ -4,6 +4,7 @@ Required properties: - compatible: Must contain one of the following: + - "renesas,scif-r8a7779" for R8A7779 (R-Car H1) SCIF compatible UART. - "renesas,scif-r8a7790" for R8A7790 (R-Car H2) SCIF compatible UART. - "renesas,scifa-r8a7790" for R8A7790 (R-Car H2) SCIFA compatible UART. - "renesas,scifb-r8a7790" for R8A7790 (R-Car H2) SCIFB compatible UART. -- cgit v1.2.3 From 7f40605a2661d17275a1aa245498f4a12ad9ca9a Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Tue, 13 May 2014 20:20:41 +0200 Subject: tty/serial: atmel_serial: Fix device tree documentation RTS pin is an active low pin. For now, this doesn't change anything as the ACTIVE_LOW flag is not handled in atmel_serial, but it will be in 3.16. Signed-off-by: Richard Genoud Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt index 17c1042b2df8..2f7aad71b3c9 100644 --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt @@ -35,7 +35,7 @@ Example: clock-names = "usart"; atmel,use-dma-rx; atmel,use-dma-tx; - rts-gpios = <&pioD 15 0>; + rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>; }; - use DMA: -- cgit v1.2.3 From 84130aace83989c1dba073ed98dad721d2060258 Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Tue, 13 May 2014 20:20:43 +0200 Subject: tty/serial: Add GPIOLIB helpers for controlling modem lines This patch add some helpers to control modem lines (CTS/RTS/DSR...) via GPIO. This will be useful for many boards which have a serial controller that only handle CTS/RTS pins (or even just RX/TX). Signed-off-by: Richard Genoud Acked-by: Greg Kroah-Hartman Tested-by: Yegor Yefremov Signed-off-by: Greg Kroah-Hartman --- Documentation/serial/driver | 25 ++++++ drivers/tty/serial/Kconfig | 3 + drivers/tty/serial/Makefile | 3 + drivers/tty/serial/serial_mctrl_gpio.c | 143 +++++++++++++++++++++++++++++++++ drivers/tty/serial/serial_mctrl_gpio.h | 110 +++++++++++++++++++++++++ 5 files changed, 284 insertions(+) create mode 100644 drivers/tty/serial/serial_mctrl_gpio.c create mode 100644 drivers/tty/serial/serial_mctrl_gpio.h (limited to 'Documentation') diff --git a/Documentation/serial/driver b/Documentation/serial/driver index c3a7689a90e6..3bba1aeb799c 100644 --- a/Documentation/serial/driver +++ b/Documentation/serial/driver @@ -429,3 +429,28 @@ thus: struct uart_port port; int my_stuff; }; + +Modem control lines via GPIO +---------------------------- + +Some helpers are provided in order to set/get modem control lines via GPIO. + +mctrl_gpio_init(dev, idx): + This will get the {cts,rts,...}-gpios from device tree if they are + present and request them, set direction etc, and return an + allocated structure. devm_* functions are used, so there's no need + to call mctrl_gpio_free(). + +mctrl_gpio_free(dev, gpios): + This will free the requested gpios in mctrl_gpio_init(). + As devm_* function are used, there's generally no need to call + this function. + +mctrl_gpio_to_gpiod(gpios, gidx) + This returns the gpio structure associated to the modem line index. + +mctrl_gpio_set(gpios, mctrl): + This will sets the gpios according to the mctrl state. + +mctrl_gpio_get(gpios, mctrl): + This will update mctrl with the gpios values. diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index d88c058634ff..4bf6d220357b 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1553,4 +1553,7 @@ config SERIAL_MEN_Z135 endmenu +config SERIAL_MCTRL_GPIO + tristate + endif # TTY diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index 712732b43917..0080cc362e09 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -92,3 +92,6 @@ obj-$(CONFIG_SERIAL_ARC) += arc_uart.o obj-$(CONFIG_SERIAL_RP2) += rp2.o obj-$(CONFIG_SERIAL_FSL_LPUART) += fsl_lpuart.o obj-$(CONFIG_SERIAL_MEN_Z135) += men_z135_uart.o + +# GPIOLIB helpers for modem control lines +obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o diff --git a/drivers/tty/serial/serial_mctrl_gpio.c b/drivers/tty/serial/serial_mctrl_gpio.c new file mode 100644 index 000000000000..bf9560ffe3f4 --- /dev/null +++ b/drivers/tty/serial/serial_mctrl_gpio.c @@ -0,0 +1,143 @@ +/* + * Helpers for controlling modem lines via GPIO + * + * Copyright (C) 2014 Paratronic S.A. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include +#include +#include +#include + +#include "serial_mctrl_gpio.h" + +struct mctrl_gpios { + struct gpio_desc *gpio[UART_GPIO_MAX]; +}; + +static const struct { + const char *name; + unsigned int mctrl; + bool dir_out; +} mctrl_gpios_desc[UART_GPIO_MAX] = { + { "cts", TIOCM_CTS, false, }, + { "dsr", TIOCM_DSR, false, }, + { "dcd", TIOCM_CD, false, }, + { "rng", TIOCM_RNG, false, }, + { "rts", TIOCM_RTS, true, }, + { "dtr", TIOCM_DTR, true, }, + { "out1", TIOCM_OUT1, true, }, + { "out2", TIOCM_OUT2, true, }, +}; + +void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl) +{ + enum mctrl_gpio_idx i; + + if (IS_ERR_OR_NULL(gpios)) + return; + + for (i = 0; i < UART_GPIO_MAX; i++) + if (!IS_ERR_OR_NULL(gpios->gpio[i]) && + mctrl_gpios_desc[i].dir_out) + gpiod_set_value(gpios->gpio[i], + !!(mctrl & mctrl_gpios_desc[i].mctrl)); +} +EXPORT_SYMBOL_GPL(mctrl_gpio_set); + +struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios, + enum mctrl_gpio_idx gidx) +{ + if (!IS_ERR_OR_NULL(gpios) && !IS_ERR_OR_NULL(gpios->gpio[gidx])) + return gpios->gpio[gidx]; + else + return NULL; +} +EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod); + +unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl) +{ + enum mctrl_gpio_idx i; + + /* + * return it unchanged if the structure is not allocated + */ + if (IS_ERR_OR_NULL(gpios)) + return *mctrl; + + for (i = 0; i < UART_GPIO_MAX; i++) { + if (!IS_ERR_OR_NULL(gpios->gpio[i]) && + !mctrl_gpios_desc[i].dir_out) { + if (gpiod_get_value(gpios->gpio[i])) + *mctrl |= mctrl_gpios_desc[i].mctrl; + else + *mctrl &= ~mctrl_gpios_desc[i].mctrl; + } + } + + return *mctrl; +} +EXPORT_SYMBOL_GPL(mctrl_gpio_get); + +struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx) +{ + struct mctrl_gpios *gpios; + enum mctrl_gpio_idx i; + int err; + + gpios = devm_kzalloc(dev, sizeof(*gpios), GFP_KERNEL); + if (!gpios) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < UART_GPIO_MAX; i++) { + gpios->gpio[i] = devm_gpiod_get_index(dev, + mctrl_gpios_desc[i].name, + idx); + + /* + * The GPIOs are maybe not all filled, + * this is not an error. + */ + if (IS_ERR_OR_NULL(gpios->gpio[i])) + continue; + + if (mctrl_gpios_desc[i].dir_out) + err = gpiod_direction_output(gpios->gpio[i], 0); + else + err = gpiod_direction_input(gpios->gpio[i]); + if (err) { + dev_dbg(dev, "Unable to set direction for %s GPIO", + mctrl_gpios_desc[i].name); + devm_gpiod_put(dev, gpios->gpio[i]); + gpios->gpio[i] = NULL; + } + } + + return gpios; +} +EXPORT_SYMBOL_GPL(mctrl_gpio_init); + +void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios) +{ + enum mctrl_gpio_idx i; + + if (IS_ERR_OR_NULL(gpios)) + return; + + for (i = 0; i < UART_GPIO_MAX; i++) + if (!IS_ERR_OR_NULL(gpios->gpio[i])) + devm_gpiod_put(dev, gpios->gpio[i]); + devm_kfree(dev, gpios); +} +EXPORT_SYMBOL_GPL(mctrl_gpio_free); diff --git a/drivers/tty/serial/serial_mctrl_gpio.h b/drivers/tty/serial/serial_mctrl_gpio.h new file mode 100644 index 000000000000..400ba0494a17 --- /dev/null +++ b/drivers/tty/serial/serial_mctrl_gpio.h @@ -0,0 +1,110 @@ +/* + * Helpers for controlling modem lines via GPIO + * + * Copyright (C) 2014 Paratronic S.A. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#ifndef __SERIAL_MCTRL_GPIO__ +#define __SERIAL_MCTRL_GPIO__ + +#include +#include +#include + +enum mctrl_gpio_idx { + UART_GPIO_CTS, + UART_GPIO_DSR, + UART_GPIO_DCD, + UART_GPIO_RNG, + UART_GPIO_RI = UART_GPIO_RNG, + UART_GPIO_RTS, + UART_GPIO_DTR, + UART_GPIO_OUT1, + UART_GPIO_OUT2, + UART_GPIO_MAX, +}; + +/* + * Opaque descriptor for modem lines controlled by GPIOs + */ +struct mctrl_gpios; + +#ifdef CONFIG_GPIOLIB + +/* + * Set state of the modem control output lines via GPIOs. + */ +void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl); + +/* + * Get state of the modem control output lines from GPIOs. + * The mctrl flags are updated and returned. + */ +unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl); + +/* + * Returns the associated struct gpio_desc to the modem line gidx + */ +struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios, + enum mctrl_gpio_idx gidx); + +/* + * Request and set direction of modem control lines GPIOs. + * devm_* functions are used, so there's no need to call mctrl_gpio_free(). + * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on + * allocation error. + */ +struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx); + +/* + * Free the mctrl_gpios structure. + * Normally, this function will not be called, as the GPIOs will + * be disposed of by the resource management code. + */ +void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios); + +#else /* GPIOLIB */ + +static inline +void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl) +{ +} + +static inline +unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl) +{ + return *mctrl; +} + +static inline +struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios, + enum mctrl_gpio_idx gidx) +{ + return ERR_PTR(-ENOSYS); +} + +static inline +struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx) +{ + return ERR_PTR(-ENOSYS); +} + +static inline +void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios) +{ +} + +#endif /* GPIOLIB */ + +#endif -- cgit v1.2.3 From e0b0baadb7a4509bdcd5ba37d0be61e2c4bb0d48 Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Tue, 13 May 2014 20:20:44 +0200 Subject: tty/serial: at91: use mctrl_gpio helpers 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 Acked-by: Greg Kroah-Hartman Acked-by: Nicolas Ferre Signed-off-by: Greg Kroah-Hartman --- .../devicetree/bindings/serial/atmel-usart.txt | 10 +- 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, 89 insertions(+), 69 deletions(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt index 2f7aad71b3c9..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. @@ -36,6 +37,11 @@ Example: atmel,use-dma-rx; atmel,use-dma-tx; 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 #include +#include #include #include @@ -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 a0282928e9c1..526453ecdaff 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 dab362c06487..4dfedd3f2e15 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 4bf6d220357b..fb57159bad3a 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -117,6 +117,7 @@ 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 #include #include +#include +#include #include #include @@ -57,6 +59,8 @@ #include +#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 */ -- cgit v1.2.3 From 06aa82e498c144c7784a6f3d3b55458b272d6146 Mon Sep 17 00:00:00 2001 From: Murali Karicheri Date: Thu, 1 May 2014 15:04:53 -0400 Subject: serial: uart: add hw flow control support configuration 8250 uart driver currently supports only software assisted hw flow control. The software assisted hw flow control maintains a hw_stopped flag in the tty structure to stop and start transmission and use modem status interrupt for the event to drive the handshake signals. This is not needed if hw has flow control capabilities. This patch adds a DT attribute for enabling hw flow control for a uart port. Also skip stop and start if this flag is present in flag field of the port structure. Signed-off-by: Murali Karicheri CC: Rob Herring CC: Pawel Moll CC: Mark Rutland CC: Ian Campbell CC: Kumar Gala CC: Randy Dunlap CC: Jiri Slaby CC: Santosh Shilimkar Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/serial/of-serial.txt | 1 + drivers/tty/serial/8250/8250_core.c | 6 ++++-- drivers/tty/serial/of_serial.c | 4 ++++ drivers/tty/serial/serial_core.c | 12 +++++++++--- 4 files changed, 18 insertions(+), 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/serial/of-serial.txt b/Documentation/devicetree/bindings/serial/of-serial.txt index 1928a3e83cd0..77054772a8f4 100644 --- a/Documentation/devicetree/bindings/serial/of-serial.txt +++ b/Documentation/devicetree/bindings/serial/of-serial.txt @@ -37,6 +37,7 @@ Optional properties: - auto-flow-control: one way to enable automatic flow control support. The driver is allowed to detect support for the capability even without this property. +- has-hw-flow-control: the hardware has flow control capability. Example: diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 111ee8acb07e..65556fc57d56 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -2333,9 +2333,11 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, * the trigger, or the MCR RTS bit is cleared. In the case where * the remote UART is not using CTS auto flow control, we must * have sufficient FIFO entries for the latency of the remote - * UART to respond. IOW, at least 32 bytes of FIFO. + * UART to respond. IOW, at least 32 bytes of FIFO. Also enable + * AFE if hw flow control is supported */ - if (up->capabilities & UART_CAP_AFE && port->fifosize >= 32) { + if ((up->capabilities & UART_CAP_AFE && (port->fifosize >= 32)) || + (port->flags & UPF_HARD_FLOW)) { up->mcr &= ~UART_MCR_AFE; if (termios->c_cflag & CRTSCTS) up->mcr |= UART_MCR_AFE; diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 99246606a256..77ec6a147522 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -182,6 +182,10 @@ static int of_platform_serial_probe(struct platform_device *ofdev) "auto-flow-control")) port8250.capabilities |= UART_CAP_AFE; + if (of_property_read_bool(ofdev->dev.of_node, + "has-hw-flow-control")) + port8250.port.flags |= UPF_HARD_FLOW; + ret = serial8250_register_8250_port(&port8250); break; } diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 9a01ee4dda6d..fbf6c5ad222f 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -174,8 +174,12 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state, if (tty->termios.c_cflag & CBAUD) uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR); } - - if (tty_port_cts_enabled(port)) { + /* + * if hw support flow control without software intervention, + * then skip the below check + */ + if (tty_port_cts_enabled(port) && + !(uport->flags & UPF_HARD_FLOW)) { spin_lock_irq(&uport->lock); if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS)) tty->hw_stopped = 1; @@ -2775,7 +2779,9 @@ void uart_handle_cts_change(struct uart_port *uport, unsigned int status) uport->icount.cts++; - if (tty_port_cts_enabled(port)) { + /* skip below code if the hw flow control is supported */ + if (tty_port_cts_enabled(port) && + !(uport->flags & UPF_HARD_FLOW)) { if (tty->hw_stopped) { if (status) { tty->hw_stopped = 0; -- cgit v1.2.3