korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2025-01-22 05:44:31 +08:00
Code Issues Packages Projects Releases Wiki Activity

ARM/serial: at91: switch atmel serial to use gpiolib

Browse Source 
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 <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This commit is contained in:
Linus Walleij 2013-11-07 10:25:55 +01:00 committed by Uwe Kleine-König
parent 6a79799d56
commit 354e57f3a0
9 changed files with 68 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
Documentation/devicetree/bindings/serial/atmel-usart.txt
View File

@ -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:

10
arch/arm/mach-at91/at91rm9200_devices.c
View File

@ -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);

7
arch/arm/mach-at91/at91sam9260_devices.c
View File

@ -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);

4
arch/arm/mach-at91/at91sam9261_devices.c
View File

@ -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);

4
arch/arm/mach-at91/at91sam9263_devices.c
View File

@ -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);

5
arch/arm/mach-at91/at91sam9g45_devices.c
View File

@ -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);

5
arch/arm/mach-at91/at91sam9rl_devices.c
View File

@ -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);

39
drivers/tty/serial/atmel_serial.c
View File

@ -35,21 +35,18 @@
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/dma-mapping.h>
#include <linux/atmel_pdc.h>
#include <linux/atmel_serial.h>
#include <linux/uaccess.h>
#include <linux/platform_data/atmel.h>
#include <linux/timer.h>
#include <linux/gpio.h>
#include <asm/io.h>
#include <asm/ioctls.h>
#ifdef CONFIG_ARM
#include <mach/cpu.h>
#include <asm/gpio.h>
#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.
* to PA21. We need to drive the pin as a GPIO.
*/
if (port->mapbase == AT91RM9200_BASE_US0) {
if (gpio_is_valid(atmel_port->rts_gpio)) {
if (mctrl & TIOCM_RTS)
at91_set_gpio_value(AT91_PIN_PA21, 0);
gpio_set_value(atmel_port->rts_gpio, 0);
else
at91_set_gpio_value(AT91_PIN_PA21, 1);
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)

1
include/linux/platform_data/atmel.h
View File

@ -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 */