[PATCH 16/46] davinci: Add MMC/SD support for DA830/OMAP-L137 EVM

[Russell King - ARM Linux]

On Fri, Oct 16, 2009 at 12:09:20PM -0700, Kevin Hilman wrote:
> From: David A. Griego <dgriego at mvista.com>
> 
> Add pinmux settings, etc. to enable the MMC/SC hardware.
> 
> Signed-off-by: David A. Griego <dgriego at mvista.com>
> Signed-off-by: Mark A. Greer <mgreer at mvista.com>
> Signed-off-by: Kevin Hilman <khilman at deeprootsystems.com>
> ---
>  arch/arm/mach-davinci/board-da830-evm.c |   43 +++++++++++++++++++++++++++++++
>  1 files changed, 43 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/mach-davinci/board-da830-evm.c b/arch/arm/mach-davinci/board-da830-evm.c
> index 39711c1..69a791a 100644
> --- a/arch/arm/mach-davinci/board-da830-evm.c
> +++ b/arch/arm/mach-davinci/board-da830-evm.c
> @@ -23,6 +23,7 @@
>  #include <mach/irqs.h>
>  #include <mach/cp_intc.h>
>  #include <mach/mux.h>
> +#include <mach/gpio.h>

linux/gpio.h

> +static int da830_evm_mmc_get_ro(int index)
> +{
> +	int val, status, gpio_num = 33;
> +
> +	status = gpio_request(gpio_num, "MMC WP\n");
> +	if (status < 0) {
> +		pr_warning("%s can not open GPIO %d\n", __func__, gpio_num);
> +		return 0;
> +	}
> +	gpio_direction_input(gpio_num);
> +	val = gpio_get_value(gpio_num);
> +	gpio_free(gpio_num);

Should this really be requesting the gpio every time it wants to be
read?  This approach sounds wrong.  Why not just request the GPIO in
the platform initialisation code, setting its direction, and merely
reading it in this function?