Re: [PATCH V2] rtc: rtc-v3020: use gpio_request_array()

From: Igor Grinberg
Date: Sun Feb 24 2013 - 03:49:02 EST




On 02/22/13 04:19, Jingoo Han wrote:
> Using gpio_request_array()/gpio_free_array() can make the code
> simpler because it can set the direction and initial value
> in one shot and the for loop is unnecessary.
>
> Also, struct v3020_gpio is removed, because the struct v3020_gpio
> is replaced with struct gpio.
>
> Signed-off-by: Jingoo Han <jg1.han@xxxxxxxxxxx>
> ---
> Changes since v1:
> - Replace gpio_request_one() with gpio_request_array()

Thanks for addressing this!
It looks much better now, although one comment below.

>
> drivers/rtc/rtc-v3020.c | 37 ++++++++++++-------------------------
> 1 files changed, 12 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/rtc/rtc-v3020.c b/drivers/rtc/rtc-v3020.c
> index bca5d67..600798c 100644
> --- a/drivers/rtc/rtc-v3020.c
> +++ b/drivers/rtc/rtc-v3020.c

[...]

> @@ -107,48 +102,40 @@ static struct v3020_chip_ops v3020_mmio_ops = {
> .write_bit = v3020_mmio_write_bit,
> };
>
> -static struct v3020_gpio v3020_gpio[] = {
> - { "RTC CS", 0 },
> - { "RTC WR", 0 },
> - { "RTC RD", 0 },
> - { "RTC IO", 0 },
> +static struct gpio v3020_gpio[] = {
> + { 0, GPIOF_OUT_INIT_HIGH, "RTC CS"},
> + { 0, GPIOF_OUT_INIT_HIGH, "RTC WR"},
> + { 0, GPIOF_OUT_INIT_HIGH, "RTC RD"},
> + { 0, GPIOF_OUT_INIT_HIGH, "RTC IO"},
> };
>
> static int v3020_gpio_map(struct v3020 *chip, struct platform_device *pdev,
> struct v3020_platform_data *pdata)
> {
> - int i, err;
> + int err;
>
> v3020_gpio[V3020_CS].gpio = pdata->gpio_cs;
> v3020_gpio[V3020_WR].gpio = pdata->gpio_wr;
> v3020_gpio[V3020_RD].gpio = pdata->gpio_rd;
> v3020_gpio[V3020_IO].gpio = pdata->gpio_io;
>
> - for (i = 0; i < ARRAY_SIZE(v3020_gpio); i++) {
> - err = gpio_request(v3020_gpio[i].gpio, v3020_gpio[i].name);
> - if (err)
> - goto err_request;
> -
> - gpio_direction_output(v3020_gpio[i].gpio, 1);
> - }
> + err = gpio_request_array(v3020_gpio, ARRAY_SIZE(v3020_gpio));
> + if (err)
> + goto err_request;
>
> chip->gpio = v3020_gpio;
>
> return 0;
>
> err_request:
> - while (--i >= 0)
> - gpio_free(v3020_gpio[i].gpio);
> + gpio_free_array(v3020_gpio, ARRAY_SIZE(v3020_gpio));

Once you use the gpio_request_array(), you don't need to care
about the error.
If gpio_request_array() fails, it does the roll back for you.
So, you just need to return err and remove the whole err_request label.

>
> return err;
> }
>
> static void v3020_gpio_unmap(struct v3020 *chip)
> {
> - int i;
> -
> - for (i = 0; i < ARRAY_SIZE(v3020_gpio); i++)
> - gpio_free(v3020_gpio[i].gpio);
> + gpio_free_array(v3020_gpio, ARRAY_SIZE(v3020_gpio));
> }
>
> static void v3020_gpio_write_bit(struct v3020 *chip, unsigned char bit)
>

--
Regards,
Igor.
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