Re: [PATCH 1/1] regulator: return set_mode is same mode isrequested

From: Liam Girdwood
Date: Mon May 17 2010 - 15:50:49 EST


On Mon, 2010-05-17 at 21:24 +0530, Sundar R Iyer wrote:
> On Mon, 2010-05-17 at 17:34 +0200, Mark Brown wrote:
> > This doesn't seem like the right error handling - if the driver has a
> > set_mode() you'd *expect* it to have a get_mode() but there's no need
> > for it to be a strict requirement.
> True. In such a case, even a valid request would be lost! So now
> in the updated patch:
> - check if get_mode is present to avoid oops;
> - if get_mode is not present, proceed anyways for the request.
>
> Here is the updated patch:
>
> >From bad0d5eb51ef84be5b100e3dd0f5a590ea0529b6 Mon Sep 17 00:00:00 2001
> From: Sundar R Iyer <sundar.iyer@xxxxxxxxxxxxxx>
> Date: Fri, 14 May 2010 15:14:17 +0530
> Subject: [PATCH 1/1] regulator: return set_mode when same mode is requested
>
> save I/O costs by returning when the same mode is
> requested for the regulator
>
> Cc: Liam Girdwood <lrg@xxxxxxxxxxxxxxx>
> Cc: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
> Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxxxxxx>
> Signed-off-by: Sundar R Iyer <sundar.iyer@xxxxxxxxxxxxxx>
> ---
> drivers/regulator/core.c | 10 ++++++++++
> 1 files changed, 10 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
> index 98e5d14..2248087 100644
> --- a/drivers/regulator/core.c
> +++ b/drivers/regulator/core.c
> @@ -1745,6 +1745,7 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode)
> {
> struct regulator_dev *rdev = regulator->rdev;
> int ret;
> + int regulator_curr_mode;
>
> mutex_lock(&rdev->mutex);
>
> @@ -1754,6 +1755,15 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode)
> goto out;
> }
>
> + /* return if the same mode is requested */
> + if (rdev->desc->ops->get_mode) {
> + regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
> + if (regulator_curr_mode == mode) {
> + ret = 0;
> + goto out;
> + }
> + }
> +
> /* constraints check */
> ret = regulator_check_mode(rdev, mode);
> if (ret < 0)


Applied.

Thanks

Liam

--
Freelance Developer, SlimLogic Ltd
ASoC and Voltage Regulator Maintainer.
http://www.slimlogic.co.uk

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