Re: [PATCH 0/3] Add ktd2692 Flash LED driver

[Sakari Ailus <sakari.ailus@iki.fi>]

Hi Bryan,

On Mon, Mar 02, 2015 at 12:07:42PM -0800, Bryan Wu wrote:
> On Mon, Mar 2, 2015 at 1:15 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote:
> > H Ingi,
> >
> > On Mon, Mar 02, 2015 at 04:14:39PM +0900, Ingi Kim wrote:
> >> Hi Jacek
> >>
> >> On 2015년 02월 27일 17:42, Jacek Anaszewski wrote:
> >> > Hi Ingi,
> >> >
> >> > On 02/27/2015 02:01 AM, Ingi Kim wrote:
> >> >> This patch supports KTD2692 flash LED driver
> >> >>
> >> >> Ingi Kim (3):
> >> >>    of: Add vendor prefix for Kinetic technologies
> >> >>    leds: ktd2692: add device tree bindings for ktd2692
> >> >>    leds: Add ktd2692 flash LED driver
> >> >>
> >> >>   .../devicetree/bindings/leds/leds-ktd2692.txt      |   19 ++
> >> >>   .../devicetree/bindings/vendor-prefixes.txt        |    1 +
> >> >>   drivers/leds/Kconfig                               |    8 +
> >> >>   drivers/leds/Makefile                              |    1 +
> >> >>   drivers/leds/leds-ktd2692.c                        |  245 ++++++++++++++++++++
> >> >>   5 files changed, 274 insertions(+)
> >> >>   create mode 100644 Documentation/devicetree/bindings/leds/leds-ktd2692.txt
> >> >>   create mode 100644 drivers/leds/leds-ktd2692.c
> >> >>
> >> >
> >> > In your device tree binding documentation there is torch-gpio mentioned,
> >> > but you seem not to use it in the driver.
> >> >
> >> > We have already LED Flash class (/drivers/leds/led-class-flash.c) for
> >> > this type of devices, which handles both torch and flash modes
> >> > (flash_strobe sysfs attribute is provided for strobing the flash).
> >> >
> >> > The reference drivers using LED Flash class are still pending [1], but I
> >> > think that at least leds-aat1290 driver is almost ready for merging.
> >> > It controls very similar device to yours.
> >> >
> >> > Another advantage of using LED Flash class is that it has been designed
> >> > to be compatible with Video for Linux 2 subsystem, which will allow for registering LED Flash class devices as a V4L2 sub-devices.
> >> >
> >> > Adding Sakari.
> >> >
> >>
> >> Ok, I'll check LED Flash class, and add torch-gpio
> >
> > Many LED flash chips include a hardware pin for torch control but few really
> > need it. If you don't, i.e. you can implement the torch using the control bus
> > instead, I think I'd probably drop it from the chip's DT bindings.
> >
> 
> Ingi, please follow Jacek's advice to use LED Flash class interface.
> I'm reviewing those leds flash drivers and probably merge them soon.
> 
> Jacek and Sakari thanks for the review.
> 
> Sakari, so what's the control bus your mentioned here?

I wasn't cc'd in the original patch so I didn't know whether it was I2C or
not. Doesn't appear to be.

-- 
Regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk