From 7485d26b7e13ee8ff82adb271ac90a996c1fe830 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Thu, 24 Jul 2008 18:36:37 +0200 Subject: [PATCH] cpm_uart: Modem control lines support This patch replaces the get_mctrl/set_mctrl stubs with modem control line read/write access through the GPIO lib. Available modem control lines are described in the device tree using GPIO bindings. The driver expect a GPIO pin for each of the CTS, RTS, DCD, DSR, DTR and RI signals. Unused control lines can be left out. Signed-off-by: Laurent Pinchart Signed-off-by: Kumar Gala --- .../dts-bindings/fsl/cpm_qe/serial.txt | 11 +++++ drivers/serial/cpm_uart/cpm_uart.h | 10 +++++ drivers/serial/cpm_uart/cpm_uart_core.c | 40 +++++++++++++++++-- 3 files changed, 58 insertions(+), 3 deletions(-) diff --git a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/serial.txt b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/serial.txt index b35f3482e3e4..2ea76d9d137c 100644 --- a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/serial.txt +++ b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/serial.txt @@ -7,6 +7,15 @@ Currently defined compatibles: - fsl,cpm2-scc-uart - fsl,qe-uart +Modem control lines connected to GPIO controllers are listed in the gpios +property as described in booting-without-of.txt, section IX.1 in the following +order: + +CTS, RTS, DCD, DSR, DTR, and RI. + +The gpios property is optional and can be left out when control lines are +not used. + Example: serial@11a00 { @@ -18,4 +27,6 @@ Example: interrupt-parent = <&PIC>; fsl,cpm-brg = <1>; fsl,cpm-command = <00800000>; + gpios = <&gpio_c 15 0 + &gpio_d 29 0>; }; diff --git a/drivers/serial/cpm_uart/cpm_uart.h b/drivers/serial/cpm_uart/cpm_uart.h index 5c76e0ae0582..5999ef5ac78e 100644 --- a/drivers/serial/cpm_uart/cpm_uart.h +++ b/drivers/serial/cpm_uart/cpm_uart.h @@ -50,6 +50,15 @@ #define SCC_WAIT_CLOSING 100 +#define GPIO_CTS 0 +#define GPIO_RTS 1 +#define GPIO_DCD 2 +#define GPIO_DSR 3 +#define GPIO_DTR 4 +#define GPIO_RI 5 + +#define NUM_GPIOS (GPIO_RI+1) + struct uart_cpm_port { struct uart_port port; u16 rx_nrfifos; @@ -82,6 +91,7 @@ struct uart_cpm_port { int wait_closing; /* value to combine with opcode to form cpm command */ u32 command; + int gpios[NUM_GPIOS]; }; extern int cpm_uart_nr; diff --git a/drivers/serial/cpm_uart/cpm_uart_core.c b/drivers/serial/cpm_uart/cpm_uart_core.c index a4f86927a74b..5e0c17f71653 100644 --- a/drivers/serial/cpm_uart/cpm_uart_core.c +++ b/drivers/serial/cpm_uart/cpm_uart_core.c @@ -43,6 +43,8 @@ #include #include #include +#include +#include #include #include @@ -96,13 +98,41 @@ static unsigned int cpm_uart_tx_empty(struct uart_port *port) static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) { - /* Whee. Do nothing. */ + struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port; + + if (pinfo->gpios[GPIO_RTS] >= 0) + gpio_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS)); + + if (pinfo->gpios[GPIO_DTR] >= 0) + gpio_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR)); } static unsigned int cpm_uart_get_mctrl(struct uart_port *port) { - /* Whee. Do nothing. */ - return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port; + unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; + + if (pinfo->gpios[GPIO_CTS] >= 0) { + if (gpio_get_value(pinfo->gpios[GPIO_CTS])) + mctrl &= ~TIOCM_CTS; + } + + if (pinfo->gpios[GPIO_DSR] >= 0) { + if (gpio_get_value(pinfo->gpios[GPIO_DSR])) + mctrl &= ~TIOCM_DSR; + } + + if (pinfo->gpios[GPIO_DCD] >= 0) { + if (gpio_get_value(pinfo->gpios[GPIO_DCD])) + mctrl &= ~TIOCM_CAR; + } + + if (pinfo->gpios[GPIO_RI] >= 0) { + if (!gpio_get_value(pinfo->gpios[GPIO_RI])) + mctrl |= TIOCM_RNG; + } + + return mctrl; } /* @@ -991,6 +1021,7 @@ static int cpm_uart_init_port(struct device_node *np, void __iomem *mem, *pram; int len; int ret; + int i; data = of_get_property(np, "fsl,cpm-brg", &len); if (!data || len != 4) { @@ -1050,6 +1081,9 @@ static int cpm_uart_init_port(struct device_node *np, goto out_pram; } + for (i = 0; i < NUM_GPIOS; i++) + pinfo->gpios[i] = of_get_gpio(np, i); + return cpm_uart_request_port(&pinfo->port); out_pram: -- 2.30.2