Hi, > -----Original Message----- > From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > Sent: Wednesday, November 15, 2023 2:41 AM > To: Sayyed, Mubin <mubin.sayyed@xxxxxxx>; > krzysztof.kozlowski+dt@xxxxxxxxxx; u.kleine-koenig@xxxxxxxxxxxxxx; > thierry.reding@xxxxxxxxx; robh+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; > tglx@xxxxxxxxxxxxx; daniel.lezcano@xxxxxxxxxx; Simek, Michal > <michal.simek@xxxxxxx> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; linux-pwm@xxxxxxxxxxxxxxx; git (AMD-Xilinx) > <git@xxxxxxx>; mubin10@xxxxxxxxx > Subject: Re: [LINUX PATCH v2 1/3] clocksource: timer-cadence-ttc: Do not > probe TTC device configured as PWM > > On 14/11/2023 13:47, Mubin Sayyed wrote: > > TTC device can act either as clocksource/clockevent or PWM generator, > > it would be decided by pwm-cells property. > > TTC PWM feature would be supported through separate driver based on > > PWM framework. > > > > If pwm-cells property is present in TTC node, it would be treated as > > PWM device, and clocksource driver should just skip it. > > > > Signed-off-by: Mubin Sayyed <mubin.sayyed@xxxxxxx> > > --- > > Changes for v2: > > - Added comment regarding pwm-cells property > > --- > > drivers/clocksource/timer-cadence-ttc.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/drivers/clocksource/timer-cadence-ttc.c > > b/drivers/clocksource/timer-cadence-ttc.c > > index 32daaac9b132..f8fcb1a4bdd0 100644 > > --- a/drivers/clocksource/timer-cadence-ttc.c > > +++ b/drivers/clocksource/timer-cadence-ttc.c > > @@ -477,6 +477,13 @@ static int __init ttc_timer_probe(struct > platform_device *pdev) > > u32 timer_width = 16; > > struct device_node *timer = pdev->dev.of_node; > > > > + /* > > + * If pwm-cells property is present in TTC node, > > + * it would be treated as PWM device. > > + */ > > + if (of_property_read_bool(timer, "#pwm-cells")) > > + return -ENODEV; > > You will introduce dmesg errors, so regressions. > [Mubin]: I will change it to "return 0" to avoid dmesg errors. > This does not look right. What you want is to bind one device driver and > choose different functionality based on properties. [Mubin]: I am doing it based on earlier discussion related to AXI Timer PWM driver. It was suggested to use #pwm-cells property for identifying role of device(PWM/clocksource) https://lore.kernel.org/linux-devicetree/20210513021631.GA878860@xxxxxxxxxxxxxxxxxx/. Thanks, Mubin > > Best regards, > Krzysztof
