From: richard.genoud@gmail.com (Richard Genoud)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 4/7] tty/serial: at91: use mctrl_gpio helpers
Date: Mon, 17 Feb 2014 17:57:24 +0100 [thread overview]
Message-ID: <1392656247-3351-5-git-send-email-richard.genoud@gmail.com> (raw)
In-Reply-To: <1392656247-3351-1-git-send-email-richard.genoud@gmail.com>
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@gmail.com>
---
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 | 100 ++++++++++++++++++++-----------
include/linux/platform_data/atmel.h | 1 -
9 files changed, 76 insertions(+), 67 deletions(-)
diff --git a/arch/arm/mach-at91/at91rm9200_devices.c b/arch/arm/mach-at91/at91rm9200_devices.c
index 605add05af7e..6dd386e3d9fe 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>
@@ -922,7 +923,6 @@ 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);
@@ -961,7 +961,14 @@ static struct resource uart0_resources[] = {
static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
- .rts_gpio = -EINVAL,
+};
+
+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);
@@ -992,7 +999,7 @@ 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);
}
}
@@ -1012,7 +1019,6 @@ 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);
@@ -1064,7 +1070,6 @@ 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);
@@ -1108,7 +1113,6 @@ 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 b52527c78b12..eda8d1679d40 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -819,7 +819,6 @@ 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);
@@ -858,7 +857,6 @@ 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);
@@ -910,7 +908,6 @@ 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);
@@ -954,7 +951,6 @@ 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);
@@ -998,7 +994,6 @@ 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);
@@ -1042,7 +1037,6 @@ 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);
@@ -1081,7 +1075,6 @@ 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 6c1a2ecc306f..b2a34740146a 100644
--- a/arch/arm/mach-at91/at91sam9261_devices.c
+++ b/arch/arm/mach-at91/at91sam9261_devices.c
@@ -880,7 +880,6 @@ 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);
@@ -919,7 +918,6 @@ 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);
@@ -963,7 +961,6 @@ 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);
@@ -1007,7 +1004,6 @@ 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 97cc2a0d6f90..4aeadddbc181 100644
--- a/arch/arm/mach-at91/at91sam9263_devices.c
+++ b/arch/arm/mach-at91/at91sam9263_devices.c
@@ -1324,7 +1324,6 @@ 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);
@@ -1363,7 +1362,6 @@ 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);
@@ -1407,7 +1405,6 @@ 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);
@@ -1451,7 +1448,6 @@ 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 c10149588e21..cb36fa872d30 100644
--- a/arch/arm/mach-at91/at91sam9g45_devices.c
+++ b/arch/arm/mach-at91/at91sam9g45_devices.c
@@ -1587,7 +1587,6 @@ 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);
@@ -1626,7 +1625,6 @@ 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);
@@ -1670,7 +1668,6 @@ 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);
@@ -1714,7 +1711,6 @@ 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);
@@ -1758,7 +1754,6 @@ 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 4120af972b61..a698bdab2cce 100644
--- a/arch/arm/mach-at91/at91sam9rl_devices.c
+++ b/arch/arm/mach-at91/at91sam9rl_devices.c
@@ -956,7 +956,6 @@ 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);
@@ -995,7 +994,6 @@ 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);
@@ -1047,7 +1045,6 @@ 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);
@@ -1091,7 +1088,6 @@ 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);
@@ -1135,7 +1131,6 @@ 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 4fe8ca16f492..59219318d7c9 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 a51b3a762948..7ac2d1dfe78f 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -43,6 +43,7 @@
#include <linux/platform_data/atmel.h>
#include <linux/timer.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <asm/io.h>
#include <asm/ioctls.h>
@@ -57,6 +58,8 @@
#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 +165,7 @@ 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 +240,46 @@ 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(atmel_port->gpios.gpio[UART_GPIO_CTS])) {
+ if (ret & TIOCM_CTS)
+ status &= ~ATMEL_US_CTS;
+ else
+ status |= ATMEL_US_CTS;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_DSR])) {
+ if (ret & TIOCM_DSR)
+ status &= ~ATMEL_US_DSR;
+ else
+ status |= ATMEL_US_DSR;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_RI])) {
+ if (ret & TIOCM_RI)
+ status &= ~ATMEL_US_RI;
+ else
+ status |= ATMEL_US_RI;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[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 +339,6 @@ 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 +351,8 @@ 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 +380,8 @@ 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 +397,7 @@ 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 +1077,7 @@ 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 +1603,7 @@ 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;
/*
@@ -2327,6 +2362,15 @@ 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)
+{
+ enum mctrl_gpio_idx i;
+ int err;
+
+ err = mctrl_gpio_init(dev, &p->gpios);
+ return err;
+}
+
static int atmel_serial_probe(struct platform_device *pdev)
{
struct atmel_uart_port *port;
@@ -2362,25 +2406,11 @@ 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, "Failed to initialize %d GPIOs. The serial port may not work as expected",
+ ret * -1);
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 */
--
1.8.5
next prev parent reply other threads:[~2014-02-17 16:57 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-17 16:57 [PATCH v3 0/7] tty/serial: Add helpers to use GPIOs to control modem lines and implement atmel_serial.c Richard Genoud
2014-02-17 16:57 ` [PATCH v3 1/7] tty/serial: Add GPIOLIB helpers for controlling modem lines Richard Genoud
2014-02-17 18:37 ` Alexander Shiyan
2014-02-18 9:59 ` Richard Genoud
2014-02-18 15:26 ` Alexander Shiyan
2014-02-20 11:20 ` Richard Genoud
2014-02-17 16:57 ` [PATCH v3 2/7] tty/serial: at91: use dev_err instead of printk Richard Genoud
2014-02-17 16:57 ` [PATCH v3 3/7] tty/serial: at91: remove unused open/close hooks Richard Genoud
2014-02-17 16:57 ` Richard Genoud [this message]
2014-02-18 15:04 ` [PATCH v3 4/7] tty/serial: at91: use mctrl_gpio helpers Alexander Shiyan
2014-02-18 15:09 ` Richard Genoud
2014-02-17 16:57 ` [PATCH v3 5/7] ARM: at91: gpio: implement get_direction Richard Genoud
2014-02-24 14:42 ` Linus Walleij
2014-02-17 16:57 ` [PATCH v3 6/7] pinctrl: at91: " Richard Genoud
2014-02-24 14:44 ` Linus Walleij
2014-02-24 14:56 ` Richard Genoud
2014-02-25 9:34 ` Linus Walleij
2014-02-17 16:57 ` [PATCH v3 7/7] tty/serial: at91: add interrupts for modem control lines Richard Genoud
2014-02-17 17:53 ` [PATCH v3 0/7] tty/serial: Add helpers to use GPIOs to control modem lines and implement atmel_serial.c Alexander Shiyan
2014-02-18 9:59 ` Richard Genoud
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