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| author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2021-05-10 16:06:37 +0200 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2021-05-25 18:13:51 +0200 |
| commit | cf38c978cf1d2a28deaf34842aef692a959fa9e6 (patch) | |
| tree | f46554112d65e06c7c04c6932e0aa087dbe8d6af /drivers/pwm/core.c | |
| parent | 6efb943b8616ec53a5e444193dccf1af9ad627b5 (diff) | |
| download | lwn-cf38c978cf1d2a28deaf34842aef692a959fa9e6.tar.gz lwn-cf38c978cf1d2a28deaf34842aef692a959fa9e6.zip | |
pwm: Make of_pwm_xlate_with_flags() work with #pwm-cells = <2>
The two functions of_pwm_simple_xlate() and of_pwm_xlate_with_flags()
are quite similar. of_pwm_simple_xlate() only supports two-cell PWM
specifiers while of_pwm_xlate_with_flags() only supports PWM specifiers
with 3 or more cells. The latter can easily be modified to behave
identically to of_pwm_simple_xlate() for two-cell PWM specifiers. This
is implemented here and allows to drop of_pwm_simple_xlate() in the next
commit.
There is a small detail that is different now in the two-cell specifier
case in of_pwm_xlate_with_flags(): pwm->args.polarity is unconditionally
initialized to PWM_POLARITY_NORMAL in the latter. I didn't find a case
where this matters and doing that explicitly is the more robust
approach.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[thierry.reding@gmail.com: fix up checkpatch warnings]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm/core.c')
| -rw-r--r-- | drivers/pwm/core.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index c4d5c0667137..6d3a1c84b053 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -126,8 +126,7 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) { struct pwm_device *pwm; - /* check, whether the driver supports a third cell for flags */ - if (pc->of_pwm_n_cells < 3) + if (pc->of_pwm_n_cells < 2) return ERR_PTR(-EINVAL); /* flags in the third cell are optional */ @@ -144,8 +143,10 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) pwm->args.period = args->args[1]; pwm->args.polarity = PWM_POLARITY_NORMAL; - if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED) - pwm->args.polarity = PWM_POLARITY_INVERSED; + if (pc->of_pwm_n_cells >= 3) { + if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED) + pwm->args.polarity = PWM_POLARITY_INVERSED; + } return pwm; } |