From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCH] leds: pwm: fix max_brightness works abnormal when active_low Date: Sun, 10 Feb 2019 17:39:30 +0100 Message-ID: <20190210163929.GA5780@amd> References: <1549802229-31170-1-git-send-email-ysxie@foxmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="SUOF0GtieIMvvwua" Return-path: Content-Disposition: inline In-Reply-To: <1549802229-31170-1-git-send-email-ysxie@foxmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Yisheng Xie Cc: jacek.anaszewski@gmail.com, linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-leds@vger.kernel.org --SUOF0GtieIMvvwua Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun 2019-02-10 20:37:09, Yisheng Xie wrote: > When leds-pwm is active_low, smaller number of duty kept in led_dat > means less brighness, so we should disable pwm when led_dat->duty is > equal to period instead of zero, which means max_brightness. Will all pwm drivers leave the signal 'low' when pwm is disabled? Not tristate or something? Plus please use temporary variable. This is really hard to read. Or maybe led_dat->active_low * new_duty =3D=3D led_dat->period ? Pavel > Signed-off-by: Yisheng Xie > --- > drivers/leds/leds-pwm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c > index df80c89..07fb772 100644 > --- a/drivers/leds/leds-pwm.c > +++ b/drivers/leds/leds-pwm.c > @@ -41,7 +41,7 @@ static void __led_pwm_set(struct led_pwm_data *led_dat) > =20 > pwm_config(led_dat->pwm, new_duty, led_dat->period); > =20 > - if (new_duty =3D=3D 0) > + if (led_dat->active_low ? new_duty =3D=3D led_dat->period : new_duty = =3D=3D 0) > pwm_disable(led_dat->pwm); > else > pwm_enable(led_dat->pwm); --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --SUOF0GtieIMvvwua Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlxgU8EACgkQMOfwapXb+vKdQACgrOCDOEQ6ShjNRvdar2Rp99HI Om4AoKv2WMNlyJQ0BmYG7EzQSfx5PlXP =9Vrw -----END PGP SIGNATURE----- --SUOF0GtieIMvvwua--