[PATCH] serial: bfin-uart: Request CTS GPIO PIN when the serial device starts up.

From: Sonic Zhang
Date: Mon Dec 05 2011 - 02:20:02 EST


From: Sonic Zhang <sonic.zhang@xxxxxxxxxx>

Serial device may be probed earlier before GPIOLIB is initialized. Requesting and
configuring CTS GPIO PIN fails in that early stage. Do it when the serial device
really starts up.

Signed-off-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx>
---
drivers/tty/serial/bfin_uart.c | 19 +++++++++----------
1 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/serial/bfin_uart.c b/drivers/tty/serial/bfin_uart.c
index c7e592d..61af5ae 100644
--- a/drivers/tty/serial/bfin_uart.c
+++ b/drivers/tty/serial/bfin_uart.c
@@ -739,8 +739,13 @@ static int bfin_serial_startup(struct uart_port *port)
pr_info("Unable to attach BlackFin UART CTS interrupt. So, disable it.\n");
}
}
- if (uart->rts_pin >= 0)
- gpio_direction_output(uart->rts_pin, 0);
+ if (uart->rts_pin >= 0) {
+ if (gpio_request(uart->rts_pin, DRIVER_NAME)) {
+ pr_info("fail to request RTS PIN at GPIO_%d\n", uart->rts_pin);
+ uart->rts_pin = -1;
+ } else
+ gpio_direction_output(uart->rts_pin, 0);
+ }
#endif
#ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
if (uart->cts_pin >= 0 && request_irq(uart->status_irq,
@@ -792,6 +797,8 @@ static void bfin_serial_shutdown(struct uart_port *port)
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
if (uart->cts_pin >= 0)
free_irq(gpio_to_irq(uart->cts_pin), uart);
+ if (uart->rts_pin >= 0)
+ gpio_free(uart->rts_pin);
#endif
#ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
if (uart->cts_pin >= 0)
@@ -1378,10 +1385,6 @@ static int bfin_serial_probe(struct platform_device *pdev)
uart->rts_pin = -1;
else
uart->rts_pin = res->start;
-# if defined(CONFIG_SERIAL_BFIN_CTSRTS)
- if (uart->rts_pin >= 0)
- gpio_request(uart->rts_pin, DRIVER_NAME);
-# endif
#endif
}

@@ -1421,10 +1424,6 @@ static int __devexit bfin_serial_remove(struct platform_device *pdev)

if (uart) {
uart_remove_one_port(&bfin_serial_reg, &uart->port);
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->rts_pin >= 0)
- gpio_free(uart->rts_pin);
-#endif
iounmap(uart->port.membase);
peripheral_free_list(
(unsigned short *)pdev->dev.platform_data);
--
1.7.0.4


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