2016-12-13 22:07 GMT+01:00 Rob Herring <robh@xxxxxxxxxx>: > On Tue, Dec 13, 2016 at 3:29 AM, Benjamin Gaignard > <benjamin.gaignard@xxxxxxxxxx> wrote: >> 2016-12-12 19:51 GMT+01:00 Rob Herring <robh@xxxxxxxxxx>: >>> On Fri, Dec 09, 2016 at 03:15:12PM +0100, Benjamin Gaignard wrote: >>>> Add bindings information for STM32 Timers >>>> >>>> version 6: >>>> - rename stm32-gtimer to stm32-timers >>>> - change compatible >>>> - add description about the IPs >>>> >>>> version 2: >>>> - rename stm32-mfd-timer to stm32-gptimer >>>> - only keep one compatible string >>>> >>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx> >>>> --- >>>> .../devicetree/bindings/mfd/stm32-timers.txt | 46 ++++++++++++++++++++++ >>>> 1 file changed, 46 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/mfd/stm32-timers.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/mfd/stm32-timers.txt b/Documentation/devicetree/bindings/mfd/stm32-timers.txt >>>> new file mode 100644 >>>> index 0000000..b30868e >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/mfd/stm32-timers.txt >>>> @@ -0,0 +1,46 @@ >>>> +STM32 Timers driver bindings >>>> + >>>> +This IP provides 3 types of timer along with PWM functionality: >>>> +- advanced-control timers consist of a 16-bit auto-reload counter driven by a programmable >>>> + prescaler, break input feature, PWM outputs and complementary PWM ouputs channels. >>>> +- general-purpose timers consist of a 16-bit or 32-bit auto-reload counter driven by a >>>> + programmable prescaler and PWM outputs. >>>> +- basic timers consist of a 16-bit auto-reload counter driven by a programmable prescaler. >>>> + >>>> +Required parameters: >>>> +- compatible: must be "st,stm32-timers" >>>> + >>>> +- reg: Physical base address and length of the controller's >>>> + registers. >>>> +- clock-names: Set to "clk_int". >>> >>> 'clk' is redundant. Also, you don't really need -names when there is >>> only one of them. >> >> I use devm_regmap_init_mmio_clk() which get the clock by it name so >> I have to define it in DT. > > Are you sure NULL is not allowed? I don't know, but at least clk_get() > allows NULL. regmap_mmio_gen_context() doesn't call clk_get() if the clock name isn't set: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/base/regmap/regmap-mmio.c?id=refs/tags/v4.9#n308 so clock-names field is really needed. > It's fine to keep, just drop the "clk_" part. ok > >> >>>> +- clocks: Phandle to the clock used by the timer module. >>>> + For Clk properties, please refer to ../clock/clock-bindings.txt >>>> + >>>> +Optional parameters: >>>> +- resets: Phandle to the parent reset controller. >>>> + See ../reset/st,stm32-rcc.txt >>>> + >>>> +Optional subnodes: >>>> +- pwm: See ../pwm/pwm-stm32.txt >>>> +- timer: See ../iio/timer/stm32-timer-trigger.txt >>>> + >>>> +Example: >>>> + timers@40010000 { >>>> + #address-cells = <1>; >>>> + #size-cells = <0>; >>>> + compatible = "st,stm32-timers"; >>>> + reg = <0x40010000 0x400>; >>>> + clocks = <&rcc 0 160>; >>>> + clock-names = "clk_int"; >>>> + >>>> + pwm { >>>> + compatible = "st,stm32-pwm"; >>>> + pinctrl-0 = <&pwm1_pins>; >>>> + pinctrl-names = "default"; >>>> + }; >>>> + >>>> + timer { >>>> + compatible = "st,stm32-timer-trigger"; >>>> + reg = <0>; >>> >>> You don't need reg here as there is only one. In turn, you don't need >>> #address-cells or #size-cells. >> >> I use "reg" to set each timer configuration. >> From hardware point of view they are all the same except for which hardware >> signals they could consume and/or send. > > This sounds okay, but... > >> "reg" is used as index of the two tables in driver code. > > this statement doesn't really sound like valid use of reg. > > If you keep reg, then the node needs a unit address (timer@0). I will do that in next version but I will wait for other maintainers (PWM/IIO) remarks before send it Thanks Benjamin > > Rob -- Benjamin Gaignard Graphic Study Group Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
