Messages in this thread | | | Date | Tue, 11 Jun 2019 18:33:18 +0200 | From | Uwe Kleine-König <> | Subject | Re: [PATCH v2 04/14] pwm: meson: change MISC_CLK_SEL_WIDTH to MISC_CLK_SEL_MASK |
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Hello,
[added clk-people to recipients]
On Sat, Jun 08, 2019 at 08:06:16PM +0200, Martin Blumenstingl wrote: > MISC_CLK_SEL_WIDTH is only used in one place where it's converted into > a bit-mask. Rename and change the macro to be a bit-mask so that > conversion is not needed anymore. No functional changes intended. > > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> > Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> > --- > drivers/pwm/pwm-meson.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c > index c62a3ac924d0..84b28ba0f903 100644 > --- a/drivers/pwm/pwm-meson.c > +++ b/drivers/pwm/pwm-meson.c > @@ -33,7 +33,7 @@ > #define MISC_A_CLK_DIV_SHIFT 8 > #define MISC_B_CLK_SEL_SHIFT 6 > #define MISC_A_CLK_SEL_SHIFT 4 > -#define MISC_CLK_SEL_WIDTH 2 > +#define MISC_CLK_SEL_MASK 0x3 > #define MISC_B_EN BIT(1) > #define MISC_A_EN BIT(0) > > @@ -463,7 +463,7 @@ static int meson_pwm_init_channels(struct meson_pwm *meson, > > channel->mux.reg = meson->base + REG_MISC_AB; > channel->mux.shift = mux_reg_shifts[i]; > - channel->mux.mask = BIT(MISC_CLK_SEL_WIDTH) - 1; > + channel->mux.mask = MISC_CLK_SEL_MASK; > channel->mux.flags = 0; > channel->mux.lock = &meson->lock; > channel->mux.table = NULL;
IMHO clk_mux is ugly here. It could easily just take
.mask = 3 << mux_reg_shifts[i],
as input parameter instead of
.mask = 3, .shift = mux_reg_shifts[i],
. Then the usage would be (IMHO) a bit more natural, the clock mask could then be defined as:
#define MISC_CLK_SEL_MASK(i) GENMASK(5 + 2 * (i), 4 + 2 * (i))
and this value could just be passed to the clk_mux.
(OK, this could be done already now, and then we'd do
channel->mux.shift = ffs(MISC_CLK_SEL_MASK(i)) - 1; channel->mux.mask = MISC_CLK_SEL_MASK(i) >> channel->mux.shift;
.)
Apart from that, I wonder if the pwm-meson driver should better use clk_register_mux instead of open coding it. (Though there doesn't seem to exists a devm_ variant of it.)
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |
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