[U-Boot] [PATCH v3 3/5] regulator: fixed: honour optionality of enable gpio

[John Keeping <john@metanate.com>]

On Thu, 15 Sep 2016 09:27:22 +0200, Marcel Ziswiler wrote:

> According to the binding documentation the fixed regulator enable GPIO
> is optional. However so far registration thereof failed if no enable
> GPIO was specified. Fix this by making it entirely optional whether an
> enable GPIO is used.
> 
> Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
> 
> ---
> 
> Changes in v3:
> - Introduce new patch to honour optionality of fixed regulator enable
>   GPIO.
> 
> Changes in v2: None
> 
>  drivers/power/regulator/fixed.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/power/regulator/fixed.c b/drivers/power/regulator/fixed.c
> index 37b8400..c68da70 100644
> --- a/drivers/power/regulator/fixed.c
> +++ b/drivers/power/regulator/fixed.c
> @@ -37,11 +37,12 @@ static int fixed_regulator_ofdata_to_platdata(struct udevice *dev)
>  	/* Set type to fixed */
>  	uc_pdata->type = REGULATOR_TYPE_FIXED;
>  
> -	/* Get fixed regulator gpio desc */
> +	/* Get fixed regulator optional enable GPIO desc */
>  	gpio = &dev_pdata->gpio;
>  	ret = gpio_request_by_name(dev, "gpio", 0, gpio, GPIOD_IS_OUT);
>  	if (ret)
> -		debug("Fixed regulator gpio - not found! Error: %d", ret);
> +		debug("Fixed reg optional enable GPIO - not found! Error: %d",
> +		      ret);

If we're changing this, should we tighten up the error handling?  It's
only ENOENT that we want to ignore here, other errors should probably
make fixed_regulator_ofdata_to_platdata() fail.

>  	/* Get optional ramp up delay */
>  	dev_pdata->startup_delay_us = fdtdec_get_uint(gd->fdt_blob,
> @@ -87,8 +88,9 @@ static bool fixed_regulator_get_enable(struct udevice *dev)
>  {
>  	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
>  
> +	/* Enable GPIO is optional */
>  	if (!dev_pdata->gpio.dev)
> -		return false;
> +		return true;

This looks much better to me (I thought I had a similar change locally
but I can't find it now).

>  	return dm_gpio_get_value(&dev_pdata->gpio);
>  }
> @@ -98,8 +100,9 @@ static int fixed_regulator_set_enable(struct udevice *dev, bool enable)
>  	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
>  	int ret;
>  
> +	/* Enable GPIO is optional */
>  	if (!dev_pdata->gpio.dev)
> -		return -ENOSYS;
> +		return 0;

I'm not sure about this change, the current behaviour seems correct to
me.  After this we're pretending that fixed_set_enable(dev, false) has
succeeded, when it has not.

>  	ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
>  	if (ret) {