| Message ID | 20190525181133.4875-5-martin.blumenstingl@googlemail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | pwm-meson: cleanups and improvements | expand |
On 25/05/2019 20:11, 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> > --- > 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 NIT I would have used GENMASK here > #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; > Anyway, it's still correct : Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Hi Neil, On Mon, May 27, 2019 at 2:26 PM Neil Armstrong <narmstrong@baylibre.com> wrote: > > On 25/05/2019 20:11, 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> > > --- > > 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 > > NIT I would have used GENMASK here that was my initial idea but I decided against it. the variant I came up with was: #define MISC_CLK_SEL_MASK GENMASK(1, 0) however, the actual offset is either 4 or 6 (depending on the PWM channel) and I felt that duplicating the macro would just make it more complicated so instead I chose to be consistent with MISC_CLK_DIV_MASK Let me know if you would like me to change it (then I prefer to update MISC_CLK_DIV_MASK as well). Martin
On Mon, May 27, 2019 at 07:46:43PM +0200, Martin Blumenstingl wrote: > Hi Neil, > > On Mon, May 27, 2019 at 2:26 PM Neil Armstrong <narmstrong@baylibre.com> wrote: > > > > On 25/05/2019 20:11, 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> > > > --- > > > 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 > > > > NIT I would have used GENMASK here > that was my initial idea but I decided against it. > the variant I came up with was: #define MISC_CLK_SEL_MASK GENMASK(1, 0) > > however, the actual offset is either 4 or 6 (depending on the PWM channel) > and I felt that duplicating the macro would just make it more complicated > so instead I chose to be consistent with MISC_CLK_DIV_MASK An option would be: #define MISC_CLK_SEL_MASK(hwid) GENMASK(1 + 4 * (hwid), 0 + 4 * (hwid)) (Note I didn't check a manual to the 4 above is probably wrong.) Best regards Uwe
Hi Uwe, On Mon, May 27, 2019 at 8:00 PM Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote: > > On Mon, May 27, 2019 at 07:46:43PM +0200, Martin Blumenstingl wrote: > > Hi Neil, > > > > On Mon, May 27, 2019 at 2:26 PM Neil Armstrong <narmstrong@baylibre.com> wrote: > > > > > > On 25/05/2019 20:11, 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> > > > > --- > > > > 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 > > > > > > NIT I would have used GENMASK here > > that was my initial idea but I decided against it. > > the variant I came up with was: #define MISC_CLK_SEL_MASK GENMASK(1, 0) > > > > however, the actual offset is either 4 or 6 (depending on the PWM channel) > > and I felt that duplicating the macro would just make it more complicated > > so instead I chose to be consistent with MISC_CLK_DIV_MASK > > An option would be: > > #define MISC_CLK_SEL_MASK(hwid) GENMASK(1 + 4 * (hwid), 0 + 4 * (hwid)) > > (Note I didn't check a manual to the 4 above is probably wrong.) that (or at least something similar) will work the catch here is: we use it to initialize the mux clock and the common clock framework expects us to set "shift" and "mask", while mask starts at bit 0 instead of shift this is how the current code is being used at the moment: channel->mux.shift = meson_pwm_per_channel_data[i].clk_sel_shift; channel->mux.mask = MISC_CLK_SEL_MASK; so with MISC_CLK_SEL_MASK this would become: channel->mux.shift = meson_pwm_per_channel_data[i].clk_sel_shift; channel->mux.mask = MISC_CLK_SEL_MASK(i) >> channel->mux.shift; or we could dynamically determine the "shift" using ffs or friends my own brain parses the variant from the patch best I'm happy to change it though if we can find something "better" Martin
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;
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> --- drivers/pwm/pwm-meson.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)