Re: [PATCH] pwm: core: cleanup pointer tests

From: Olliver Schinagl
Date: Fri Aug 07 2015 - 14:19:01 EST


Hey list,

After working on a new pwm-driver I noticed that not everybody actually has the set_polarity op and thus its an optional property. For a moment I figured I could add a 'software' polarity function by inverting the calculation of the on/off time, but I don't even have the hardware to test it so ...

Sorry for the noise, this patch can be ignored.

Olliver

On 07-08-15 16:49, Olliver Schinagl wrote:
From: Olliver Schinagl <oliver@xxxxxxxxxxx>

pwm_set_polarity() checks if there's ops and polarity function pointers.
Most of these pointers are actually checked when a chip is added via
pwm_add, except for set_polarity.

This patch adds set_polarity to the list of functions to test on
pwmchip_add_with_polarity(); and removes these checks from
pwm_set_polarity.

The pwm should be valid, as it was checked during
pwmchip_add_with_polarity().

Signed-off-by: Olliver Schinagl <oliver@xxxxxxxxxxx>
---
drivers/pwm/core.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 3a7769f..66fd5fd 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -239,7 +239,8 @@ int pwmchip_add_with_polarity(struct pwm_chip *chip,
int ret;
if (!chip || !chip->dev || !chip->ops || !chip->ops->config ||
- !chip->ops->enable || !chip->ops->disable || !chip->npwm)
+ !chip->ops->set_polarity || !chip->ops->enable ||
+ !chip->ops->disable || !chip->npwm)
return -EINVAL;
mutex_lock(&pwm_lock);
@@ -449,12 +450,9 @@ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
{
int err;
- if (!pwm || !pwm->chip->ops)
+ if (!pwm)
return -EINVAL;
- if (!pwm->chip->ops->set_polarity)
- return -ENOSYS;
-
if (test_bit(PWMF_ENABLED, &pwm->flags))
return -EBUSY;

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