| Message ID | 1462634508-24961-3-git-send-email-ivo.g.dimitrov.75@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, May 07, 2016 at 06:21:43PM +0300, Ivaylo Dimitrov wrote: > OMAP GP timers can have different input clocks that allow different PWM > frequencies. However, there is no other way of setting the clock source but > through clocks or clock-names properties of the timer itself. This limits > PWM functionality to only the frequencies allowed by the particular clock > source. Allowing setting the clock source by PWM rather than by timer > allows different PWMs to have different ranges by not hard-wiring the clock > source to the timer. > > Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> > --- > Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt | 4 ++++ > drivers/pwm/pwm-omap-dmtimer.c | 12 +++++++----- > 2 files changed, 11 insertions(+), 5 deletions(-) Acked-by: Rob Herring <robh@kernel.org> -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt b/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt index 5befb53..2e53324 100644 --- a/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt +++ b/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt @@ -9,6 +9,10 @@ Required properties: Optional properties: - ti,prescaler: Should be a value between 0 and 7, see the timers datasheet +- ti,clock-source: Set dmtimer parent clock, values between 0 and 2: + - 0x00 - high-frequency system clock (timer_sys_ck) + - 0x01 - 32-kHz always-on clock (timer_32k_ck) + - 0x02 - external clock (timer_ext_ck, OMAP2 only) Example: pwm9: dmtimer-pwm@9 { diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c index b7e6ecb..95964c6 100644 --- a/drivers/pwm/pwm-omap-dmtimer.c +++ b/drivers/pwm/pwm-omap-dmtimer.c @@ -245,7 +245,7 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) struct pwm_omap_dmtimer_chip *omap; struct pwm_omap_dmtimer_pdata *pdata; pwm_omap_dmtimer *dm_timer; - u32 prescaler; + u32 v; int status; pdata = dev_get_platdata(&pdev->dev); @@ -306,10 +306,12 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) if (pm_runtime_active(&omap->dm_timer_pdev->dev)) omap->pdata->stop(omap->dm_timer); - /* setup dmtimer prescaler */ - if (!of_property_read_u32(pdev->dev.of_node, "ti,prescaler", - &prescaler)) - omap->pdata->set_prescaler(omap->dm_timer, prescaler); + if (!of_property_read_u32(pdev->dev.of_node, "ti,prescaler", &v)) + omap->pdata->set_prescaler(omap->dm_timer, v); + + /* setup dmtimer clock source */ + if (!of_property_read_u32(pdev->dev.of_node, "ti,clock-source", &v)) + omap->pdata->set_source(omap->dm_timer, v); omap->chip.dev = &pdev->dev; omap->chip.ops = &pwm_omap_dmtimer_ops;
OMAP GP timers can have different input clocks that allow different PWM frequencies. However, there is no other way of setting the clock source but through clocks or clock-names properties of the timer itself. This limits PWM functionality to only the frequencies allowed by the particular clock source. Allowing setting the clock source by PWM rather than by timer allows different PWMs to have different ranges by not hard-wiring the clock source to the timer. Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> --- Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt | 4 ++++ drivers/pwm/pwm-omap-dmtimer.c | 12 +++++++----- 2 files changed, 11 insertions(+), 5 deletions(-)