[PATCH v2 2/4] ARM: mx5/babbage: Use gpio_request_one in babbage_usbhub_reset

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Thu Mar 17 12:10:47 EDT 2011


On Thu, Mar 17, 2011 at 12:55:57PM -0300, Fabio Estevam wrote:
> Current code inside babbage_usbhub_reset uses gpio_direction_output with initial value of the GPIO and also sets 
> the GPIO value via gpio_set_value to the same level right after. This is not needed. 
> 
> By using gpio_request_one it is possible to set the direction and initial value in one shot.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>

Thanks
Uwe

> ---
> Changes since v1:
> 
> - Changed the comment about USB reset and Deassert reset
>  arch/arm/mach-mx5/board-mx51_babbage.c |   12 +++++-------
>  1 files changed, 5 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/arm/mach-mx5/board-mx51_babbage.c b/arch/arm/mach-mx5/board-mx51_babbage.c
> index bea4e41..ab50aa9 100644
> --- a/arch/arm/mach-mx5/board-mx51_babbage.c
> +++ b/arch/arm/mach-mx5/board-mx51_babbage.c
> @@ -208,18 +208,16 @@ static inline void babbage_usbhub_reset(void)
>  {
>  	int ret;
>  
> -	/* Bring USB hub out of reset */
> -	ret = gpio_request(BABBAGE_USB_HUB_RESET, "GPIO1_7");
> +	/* Reset USB hub */
> +	ret = gpio_request_one(BABBAGE_USB_HUB_RESET,
> +					GPIOF_OUT_INIT_LOW, "GPIO1_7");
>  	if (ret) {
>  		printk(KERN_ERR"failed to get GPIO_USB_HUB_RESET: %d\n", ret);
>  		return;
>  	}
> -	gpio_direction_output(BABBAGE_USB_HUB_RESET, 0);
>  
> -	/* USB HUB RESET - De-assert USB HUB RESET_N */
> -	msleep(1);
> -	gpio_set_value(BABBAGE_USB_HUB_RESET, 0);
> -	msleep(1);
> +	msleep(2);
> +	/* Deassert reset */
>  	gpio_set_value(BABBAGE_USB_HUB_RESET, 1);
>  }
>  
> -- 
> 1.6.0.4
> 
> 
> 

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |



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