[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20180416122426.72lhi3hrk2g7y526@dell>
Date: Mon, 16 Apr 2018 13:24:26 +0100
From: Lee Jones <lee.jones@...aro.org>
To: Fabrice Gasnier <fabrice.gasnier@...com>
Cc: thierry.reding@...il.com, alexandre.torgue@...com,
benjamin.gaignard@...aro.org, robh+dt@...nel.org,
mark.rutland@....com, linux@...linux.org.uk,
mcoquelin.stm32@...il.com, benjamin.gaignard@...com,
devicetree@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
linux-kernel@...r.kernel.org, linux-pwm@...r.kernel.org
Subject: Re: [PATCH v3 3/6] pwm: stm32: add capture support
On Fri, 30 Mar 2018, Fabrice Gasnier wrote:
> Add support for PMW input mode on pwm-stm32. STM32 timers support
> period and duty cycle capture as long as they have at least two PWM
> channels. One capture channel is used for period (rising-edge), one
> for duty-cycle (falling-edge).
> When there's only one channel available, only period can be captured.
> Duty-cycle is simply zero'ed in such a case.
>
> Capture requires exclusive access (e.g. no pwm output running at the
> same time, to protect common prescaler).
> Timer DMA burst mode (from MFD core) is being used, to take two
> snapshots of capture registers (upon each period rising edge).
>
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@...com>
> Reviewed-by: Benjamin Gaignard <benjamin.gaignard@...aro.org>
> Acked-by: Thierry Reding <thierry.reding@...il.com>
> ---
> Changes in v3:
> - update stm32_timers_dma_burst_read() call: don't pass ddata structure,
> use MFD parent device structure instead since MFD core update.
>
> Changes in v2:
> - DMA handling has been moved to MFD core. Rework capture routines to
> use it.
> ---
> drivers/pwm/pwm-stm32.c | 176 +++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/stm32-timers.h | 11 +++
For my own reference:
Acked-for-MFD-by: Lee Jones <lee.jones@...aro.org>
> 2 files changed, 187 insertions(+)
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
Powered by blists - more mailing lists