Re: [PATCH 5/8] minnowboard-gpio: Export MinnowBoard expansion GPIO

From: Andy Shevchenko
Date: Wed Jun 26 2013 - 03:55:43 EST


On Tue, 2013-06-25 at 18:53 -0700, Darren Hart wrote:
> Request and export the user-configurable GPIO lines to sysfs. This provides a
> label readable in /debugfs/gpio and a simple interface for experimenting with
> GPIO on the MinnowBoard.
>
> This is separate from the minnowboard driver to provide users with the
> flexibility to write kernel drivers for their own devices using these GPIO
> lines.

Few comments below.

> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -35,6 +35,24 @@ config MINNOWBOARD
>
> If you have a MinnowBoard, say Y or M here.
>
> +if MINNOWBOARD
> +config MINNOWBOARD_GPIO
> + tristate "MinnowBoard Expansion GPIO"
> + depends on MINNOWBOARD
> + default n

Like you already had been told you don't need to have default n.

> --- /dev/null
> +++ b/drivers/platform/x86/minnowboard-gpio.c

> +#include <linux/platform_device.h>
> +#include <linux/module.h>
> +#include <linux/gpio.h>
> +#include <linux/gpio_keys.h>
> +#include <linux/input.h>
> +#include <linux/minnowboard.h>

+ empty line here?

> +#include "minnowboard-gpio.h"

> +static int __init minnow_gpio_module_init(void)
> +{
> + int err;
> +
> + err = -ENODEV;
> + if (!minnow_detect())
> + goto out;
> +
> +#ifdef MODULE
> +#ifdef CONFIG_MINNOWBOARD_MODULE

And less ifdefs with IS_MODULE().

> + if (request_module("minnowboard"))
> + goto out;
> +#endif
> +#endif
> +
> + /* Auxillary Expansion GPIOs */
> + if (!minnow_lvds_detect()) {
> + pr_debug("LVDS_DETECT not asserted, configuring Aux GPIO lines\n");
> + err = gpio_request_array(expansion_aux_gpios,
> + ARRAY_SIZE(expansion_aux_gpios));
> + if (err) {
> + pr_err("Failed to request expansion aux GPIO lines\n");
> + goto out;
> + }
> + } else {
> + pr_debug("LVDS_DETECT asserted, ignoring aux GPIO lines\n");
> + }
> +
> + /* Expansion GPIOs */
> + err = gpio_request_array(expansion_gpios, ARRAY_SIZE(expansion_gpios));
> + if (err) {
> + pr_err("Failed to request expansion GPIO lines\n");
> + if (minnow_lvds_detect())
> + gpio_free_array(expansion_aux_gpios,
> + ARRAY_SIZE(expansion_aux_gpios));
> + goto out;
> + }
> +
> + out:
> + return err;

Are you planning to add something else to 'out' path?
Otherwise I think it will look better if you do return instead of
[useless] gotos.


--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
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