On Wed, Feb 20, 2013 at 12:36 AM, Kim, Milo <[email protected]> wrote:
> Some LED devices support flash/torch functionality through the LED subsystem.
> This patch enables direct LED trigger controls by the driver.
> Flash on/off and torch on/off can be done simply by other driver space.
> Two trigger APIs are added, ledtrig_flash_ctrl() and ledtrig_torch_ctrl().
>
> Signed-off-by: Milo(Woogyom) Kim <[email protected]>
> ---
> drivers/leds/trigger/Kconfig | 8 +++++
> drivers/leds/trigger/Makefile | 1 +
> drivers/leds/trigger/ledtrig-camera.c | 57 +++++++++++++++++++++++++++++++++
> include/linux/leds.h | 8 +++++
> 4 files changed, 74 insertions(+)
> create mode 100644 drivers/leds/trigger/ledtrig-camera.c
>
> diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig
> index eaa286d..49794b4 100644
> --- a/drivers/leds/trigger/Kconfig
> +++ b/drivers/leds/trigger/Kconfig
> @@ -100,4 +100,12 @@ config LEDS_TRIGGER_TRANSIENT
> GPIO/PWM based hardware.
> If unsure, say Y.
>
> +config LEDS_TRIGGER_CAMERA
> + tristate "LED Camera Flash/Torch Trigger"
> + depends on LEDS_TRIGGERS
> + help
> + This allows LEDs to be controlled as a camera flash/torch device.
> + This enables direct flash/torch on/off by the driver, kernel space.
> + If unsure, say Y.
> +
> endif # LEDS_TRIGGERS
> diff --git a/drivers/leds/trigger/Makefile b/drivers/leds/trigger/Makefile
> index 554e46e..1abf48d 100644
> --- a/drivers/leds/trigger/Makefile
> +++ b/drivers/leds/trigger/Makefile
> @@ -7,3 +7,4 @@ obj-$(CONFIG_LEDS_TRIGGER_GPIO) += ledtrig-gpio.o
> obj-$(CONFIG_LEDS_TRIGGER_CPU) += ledtrig-cpu.o
> obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o
> obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT) += ledtrig-transient.o
> +obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o
> diff --git a/drivers/leds/trigger/ledtrig-camera.c b/drivers/leds/trigger/ledtrig-camera.c
> new file mode 100644
> index 0000000..9bd73a8
> --- /dev/null
> +++ b/drivers/leds/trigger/ledtrig-camera.c
> @@ -0,0 +1,57 @@
> +/*
> + * Camera Flash and Torch On/Off Trigger
> + *
> + * based on ledtrig-ide-disk.c
> + *
> + * Copyright 2013 Texas Instruments
> + *
> + * Author: Milo(Woogyom) Kim <[email protected]>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/leds.h>
> +
> +DEFINE_LED_TRIGGER(ledtrig_flash);
> +DEFINE_LED_TRIGGER(ledtrig_torch);
> +
> +void ledtrig_flash_ctrl(bool on)
> +{
> + enum led_brightness brt = on ? LED_FULL : LED_OFF;
> +
> + led_trigger_event(ledtrig_flash, brt);
> +}
> +EXPORT_SYMBOL_GPL(ledtrig_flash_ctrl);
> +
> +void ledtrig_torch_ctrl(bool on)
> +{
> + enum led_brightness brt = on ? LED_FULL : LED_OFF;
> +
> + led_trigger_event(ledtrig_torch, brt);
> +}
> +EXPORT_SYMBOL_GPL(ledtrig_torch_ctrl);
> +
> +static int __init ledtrig_camera_init(void)
> +{
> + led_trigger_register_simple("flash", &ledtrig_flash);
> + led_trigger_register_simple("torch", &ledtrig_torch);
> + return 0;
> +}
> +module_init(ledtrig_camera_init);
> +
> +static void __exit ledtrig_camera_exit(void)
> +{
> + led_trigger_unregister_simple(ledtrig_torch);
> + led_trigger_unregister_simple(ledtrig_flash);
> +}
> +module_exit(ledtrig_camera_exit);
> +
> +MODULE_DESCRIPTION("LED Trigger for Camera Flash/Torch Control");
> +MODULE_AUTHOR("Milo Kim");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/leds.h b/include/linux/leds.h
> index 0d9b5ee..197ca9e 100644
> --- a/include/linux/leds.h
> +++ b/include/linux/leds.h
> @@ -215,6 +215,14 @@ extern void ledtrig_ide_activity(void);
> #define ledtrig_ide_activity() do {} while(0)
> #endif
>
> +#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
> +extern void ledtrig_flash_ctrl(bool on);
> +extern void ledtrig_torch_ctrl(bool on);
> +#else
> +#define ledtrig_flash_ctrl(x) do {} while(0)
> +#define ledtrig_torch_ctrl(x) do {} while(0)
It's better don't use #define macros but use real empty functions like this:
static inline void ledtrig_flash_ctrl(bool on)
{
return;
}
> +#endif
> +
> /*
> * Generic LED platform data for describing LED names and default triggers.
> */
> --
> 1.7.9.5
>
>
> Best Regards,
> Milo
>
>
> > +#if defined(CONFIG_LEDS_TRIGGER_CAMERA) ||
> defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
> > +extern void ledtrig_flash_ctrl(bool on);
> > +extern void ledtrig_torch_ctrl(bool on);
> > +#else
> > +#define ledtrig_flash_ctrl(x) do {} while(0)
> > +#define ledtrig_torch_ctrl(x) do {} while(0)
>
> It's better don't use #define macros but use real empty functions like
> this:
> static inline void ledtrig_flash_ctrl(bool on)
> {
> return;
> }
I agree, but other trigger functions are declared as do-while definition.
So I would let them unify if it's not critical.
I'd like to have your opinion, which is better.
Thanks,
Milo
On Wed, Mar 13, 2013 at 4:16 PM, Kim, Milo <[email protected]> wrote:
>> > +#if defined(CONFIG_LEDS_TRIGGER_CAMERA) ||
>> defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
>> > +extern void ledtrig_flash_ctrl(bool on);
>> > +extern void ledtrig_torch_ctrl(bool on);
>> > +#else
>> > +#define ledtrig_flash_ctrl(x) do {} while(0)
>> > +#define ledtrig_torch_ctrl(x) do {} while(0)
>>
>> It's better don't use #define macros but use real empty functions like
>> this:
>> static inline void ledtrig_flash_ctrl(bool on)
>> {
>> return;
>> }
>
> I agree, but other trigger functions are declared as do-while definition.
> So I would let them unify if it's not critical.
> I'd like to have your opinion, which is better.
>
> Thanks,
> Milo
I did same thing before, Andrew Morton corrected me like this. Please
feel free to submit patch to move other macros to empty functions.
Thanks,
-Bryan
> -----Original Message-----
> From: Bryan Wu [mailto:[email protected]]
> Sent: Thursday, March 14, 2013 8:19 AM
> To: Kim, Milo
> Cc: [email protected]; [email protected]; Jeong,
> Daniel
> Subject: Re: [PATCH 2/3] leds: add LED Trigger for camera function
>
> On Wed, Mar 13, 2013 at 4:16 PM, Kim, Milo <[email protected]> wrote:
> >> > +#if defined(CONFIG_LEDS_TRIGGER_CAMERA) ||
> >> defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
> >> > +extern void ledtrig_flash_ctrl(bool on);
> >> > +extern void ledtrig_torch_ctrl(bool on);
> >> > +#else
> >> > +#define ledtrig_flash_ctrl(x) do {} while(0)
> >> > +#define ledtrig_torch_ctrl(x) do {} while(0)
> >>
> >> It's better don't use #define macros but use real empty functions
> like
> >> this:
> >> static inline void ledtrig_flash_ctrl(bool on)
> >> {
> >> return;
> >> }
> >
> > I agree, but other trigger functions are declared as do-while
> definition.
> > So I would let them unify if it's not critical.
> > I'd like to have your opinion, which is better.
> >
> > Thanks,
> > Milo
>
> I did same thing before, Andrew Morton corrected me like this. Please
> feel free to submit patch to move other macros to empty functions.
>
> Thanks,
> -Bryan
OK, it's clear now. I'll send the patch-set with previous one,
'[PATCH 3/3] leds: lm355x, lm3642: support Camera LED triggers for flash/torch'.
Thanks!
-Milo