[PATCH v6 00/10] LED / flash API integration

[PATCH v6 00/10] LED / flash API integration

[Jacek Anaszewski]

This is a sixth non-RFC version of LED / flash API integration
series [1]. It is based on linux_next-20150427.

================
Changes since v5
================
- renamed v4l2-flash module to v4l2-flash-led-class and applied
  other related modifications spotted by Sakari
- fixed not released of_node reference in max77693-led driver

================
Changes since v4
================
- adapted leds-max77693 and leds-aat1290 drivers to the recent
  modifications in leds/common.txt bindings documentation and
  changed the behaviour when properties are missing
- modified DT bindings documenation for the aforementioned
  drivers
- removed unjustified use of goto in the leds-aat1290 driver
- fixed lack of of_node_put in leds-aat1290 driver, after parsing
  DT child node 
- removed patch adding 'skyworks' vendor prefix, as the entry
  has been recently added

================
Changes since v2
================
- improved leds/common DT bindings documentation
- improved max77693-led DT documentation
- fixed validation of DT confguration for leds-max77693 by
  minimal values in joint iouts case
- removed trigger-type property from leds-max77693 bindings
  and adjusted the driver accordingly
- improved LED Flash class documentation related to v4l2-flash sub-device
  initialization
- excluded from leds-aat1290 DT bindings documentation the part
  related to handling external strobe sources

================
Changes since v1
================

- excluded exynos4-is media device related patches, as there is
  consenus required related to flash devices handling in media device
  DT bindings
- modifications around LED Flash class settings and v4l2 flash config
  initialization in LED Flash class drivers and v4l2-flash wrapper
- switched to using DT node name as a device name for leds-max77693
  and leds-aat1290 drivers, in case DT 'label' property is absent
- dropped OF dependecy for v4l2-flash wrapper
- moved LED_FAULTS definitions from led-class-flash.h to uapi/linux/leds.h
- allowed for multiple clients of v4l2-flash sub-device

======================
Changes since RFC v13:
======================

- reduced number of patches - some of them have been merged
- slightly modified max77693-led device naming
- fixed issues in v4l2-flash helpers detected with yavta
- cleaned up AAT1290 device tree documentation
- added GPIOLIB dependecy to AAT1290 related entry in Kconfig

Thanks,
Jacek Anaszewski

[1] http://www.spinics.net/lists/kernel/msg1944538.html

Jacek Anaszewski (10):
  leds: unify the location of led-trigger API
  DT: Add documentation for the mfd Maxim max77693
  leds: Add support for max77693 mfd flash cell
  DT: Add documentation for the Skyworks AAT1290
  leds: Add driver for AAT1290 flash LED controller
  media: Add registration helpers for V4L2 flash sub-devices
  Documentation: leds: Add description of v4l2-flash sub-device
  leds: max77693: add support for V4L2 Flash sub-device
  DT: aat1290: Document handling external strobe sources
  leds: aat1290: add support for V4L2 Flash sub-device

 .../devicetree/bindings/leds/leds-aat1290.txt      |   73 ++
 Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++
 Documentation/leds/leds-class-flash.txt            |   47 +
 drivers/leds/Kconfig                               |   19 +
 drivers/leds/Makefile                              |    2 +
 drivers/leds/leds-aat1290.c                        |  577 ++++++++++
 drivers/leds/leds-max77693.c                       | 1104 ++++++++++++++++++++
 drivers/leds/leds.h                                |   24 -
 drivers/media/v4l2-core/Kconfig                    |   11 +
 drivers/media/v4l2-core/Makefile                   |    2 +
 drivers/media/v4l2-core/v4l2-flash-led-class.c     |  626 +++++++++++
 include/linux/leds.h                               |   25 +
 include/media/v4l2-flash-led-class.h               |  145 +++
 13 files changed, 2698 insertions(+), 24 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-aat1290.txt
 create mode 100644 drivers/leds/leds-aat1290.c
 create mode 100644 drivers/leds/leds-max77693.c
 create mode 100644 drivers/media/v4l2-core/v4l2-flash-led-class.c
 create mode 100644 include/media/v4l2-flash-led-class.h

-- 
1.7.9.5

[PATCH v6 01/10] leds: unify the location of led-trigger API

[Jacek Anaszewski]

Part of led-trigger API was in the private drivers/leds/leds.h header.
Move it to the include/linux/leds.h header to unify the API location
and announce it as public. It has been already exported from
led-triggers.c with EXPORT_SYMBOL_GPL macro. The no-op definitions are
changed from macros to inline to match the style of the surrounding code.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/leds/leds.h  |   24 ------------------------
 include/linux/leds.h |   25 +++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 24 deletions(-)

diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
index 79efe57..bc89d7a 100644
--- a/drivers/leds/leds.h
+++ b/drivers/leds/leds.h
@@ -13,7 +13,6 @@
 #ifndef __LEDS_H_INCLUDED
 #define __LEDS_H_INCLUDED
 
-#include <linux/device.h>
 #include <linux/rwsem.h>
 #include <linux/leds.h>
 
@@ -50,27 +49,4 @@ void led_stop_software_blink(struct led_classdev *led_cdev);
 extern struct rw_semaphore leds_list_lock;
 extern struct list_head leds_list;
 
-#ifdef CONFIG_LEDS_TRIGGERS
-void led_trigger_set_default(struct led_classdev *led_cdev);
-void led_trigger_set(struct led_classdev *led_cdev,
-			struct led_trigger *trigger);
-void led_trigger_remove(struct led_classdev *led_cdev);
-
-static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
-{
-	return led_cdev->trigger_data;
-}
-
-#else
-#define led_trigger_set_default(x) do {} while (0)
-#define led_trigger_set(x, y) do {} while (0)
-#define led_trigger_remove(x) do {} while (0)
-#define led_get_trigger_data(x) (NULL)
-#endif
-
-ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
-			const char *buf, size_t count);
-ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
-			char *buf);
-
 #endif	/* __LEDS_H_INCLUDED */
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 9a2b000..b122eea 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -12,6 +12,7 @@
 #ifndef __LINUX_LEDS_H_INCLUDED
 #define __LINUX_LEDS_H_INCLUDED
 
+#include <linux/device.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/rwsem.h>
@@ -222,6 +223,11 @@ struct led_trigger {
 	struct list_head  next_trig;
 };
 
+ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count);
+ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
+			char *buf);
+
 /* Registration functions for complex triggers */
 extern int led_trigger_register(struct led_trigger *trigger);
 extern void led_trigger_unregister(struct led_trigger *trigger);
@@ -238,6 +244,16 @@ extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
 				      unsigned long *delay_on,
 				      unsigned long *delay_off,
 				      int invert);
+extern void led_trigger_set_default(struct led_classdev *led_cdev);
+extern void led_trigger_set(struct led_classdev *led_cdev,
+			struct led_trigger *trigger);
+extern void led_trigger_remove(struct led_classdev *led_cdev);
+
+static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
+{
+	return led_cdev->trigger_data;
+}
+
 /**
  * led_trigger_rename_static - rename a trigger
  * @name: the new trigger name
@@ -267,6 +283,15 @@ static inline void led_trigger_register_simple(const char *name,
 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
 static inline void led_trigger_event(struct led_trigger *trigger,
 				enum led_brightness event) {}
+static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
+static inline void led_trigger_set(struct led_classdev *led_cdev,
+				struct led_trigger *trigger) {}
+static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
+static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_LEDS_TRIGGERS */
 
 /* Trigger specific functions */
-- 
1.7.9.5

Re: [PATCH v6 01/10] leds: unify the location of led-trigger API

[Bryan Wu]

On Tue, Apr 28, 2015 at 12:18 AM, Jacek Anaszewski
<j.anaszewski@samsung.com> wrote:
> Part of led-trigger API was in the private drivers/leds/leds.h header.
> Move it to the include/linux/leds.h header to unify the API location
> and announce it as public. It has been already exported from
> led-triggers.c with EXPORT_SYMBOL_GPL macro. The no-op definitions are
> changed from macros to inline to match the style of the surrounding code.
>
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Applied, thanks,
-Bryan

> ---
>  drivers/leds/leds.h  |   24 ------------------------
>  include/linux/leds.h |   25 +++++++++++++++++++++++++
>  2 files changed, 25 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
> index 79efe57..bc89d7a 100644
> --- a/drivers/leds/leds.h
> +++ b/drivers/leds/leds.h
> @@ -13,7 +13,6 @@
>  #ifndef __LEDS_H_INCLUDED
>  #define __LEDS_H_INCLUDED
>
> -#include <linux/device.h>
>  #include <linux/rwsem.h>
>  #include <linux/leds.h>
>
> @@ -50,27 +49,4 @@ void led_stop_software_blink(struct led_classdev *led_cdev);
>  extern struct rw_semaphore leds_list_lock;
>  extern struct list_head leds_list;
>
> -#ifdef CONFIG_LEDS_TRIGGERS
> -void led_trigger_set_default(struct led_classdev *led_cdev);
> -void led_trigger_set(struct led_classdev *led_cdev,
> -                       struct led_trigger *trigger);
> -void led_trigger_remove(struct led_classdev *led_cdev);
> -
> -static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
> -{
> -       return led_cdev->trigger_data;
> -}
> -
> -#else
> -#define led_trigger_set_default(x) do {} while (0)
> -#define led_trigger_set(x, y) do {} while (0)
> -#define led_trigger_remove(x) do {} while (0)
> -#define led_get_trigger_data(x) (NULL)
> -#endif
> -
> -ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
> -                       const char *buf, size_t count);
> -ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
> -                       char *buf);
> -
>  #endif /* __LEDS_H_INCLUDED */
> diff --git a/include/linux/leds.h b/include/linux/leds.h
> index 9a2b000..b122eea 100644
> --- a/include/linux/leds.h
> +++ b/include/linux/leds.h
> @@ -12,6 +12,7 @@
>  #ifndef __LINUX_LEDS_H_INCLUDED
>  #define __LINUX_LEDS_H_INCLUDED
>
> +#include <linux/device.h>
>  #include <linux/list.h>
>  #include <linux/mutex.h>
>  #include <linux/rwsem.h>
> @@ -222,6 +223,11 @@ struct led_trigger {
>         struct list_head  next_trig;
>  };
>
> +ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
> +                       const char *buf, size_t count);
> +ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
> +                       char *buf);
> +
>  /* Registration functions for complex triggers */
>  extern int led_trigger_register(struct led_trigger *trigger);
>  extern void led_trigger_unregister(struct led_trigger *trigger);
> @@ -238,6 +244,16 @@ extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
>                                       unsigned long *delay_on,
>                                       unsigned long *delay_off,
>                                       int invert);
> +extern void led_trigger_set_default(struct led_classdev *led_cdev);
> +extern void led_trigger_set(struct led_classdev *led_cdev,
> +                       struct led_trigger *trigger);
> +extern void led_trigger_remove(struct led_classdev *led_cdev);
> +
> +static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
> +{
> +       return led_cdev->trigger_data;
> +}
> +
>  /**
>   * led_trigger_rename_static - rename a trigger
>   * @name: the new trigger name
> @@ -267,6 +283,15 @@ static inline void led_trigger_register_simple(const char *name,
>  static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
>  static inline void led_trigger_event(struct led_trigger *trigger,
>                                 enum led_brightness event) {}
> +static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
> +static inline void led_trigger_set(struct led_classdev *led_cdev,
> +                               struct led_trigger *trigger) {}
> +static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
> +static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
> +{
> +       return NULL;
> +}
> +
>  #endif /* CONFIG_LEDS_TRIGGERS */
>
>  /* Trigger specific functions */
> --
> 1.7.9.5
>

Re: [PATCH v6 01/10] leds: unify the location of led-trigger API

[Bryan Wu]

[PATCH v6 02/10] DT: Add documentation for the mfd Maxim max77693

[Jacek Anaszewski]

This patch adds device tree binding documentation for
the flash cell of the Maxim max77693 multifunctional device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: devicetree@vger.kernel.org
---
 Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/max77693.txt b/Documentation/devicetree/bindings/mfd/max77693.txt
index 38e6440..d342584 100644
--- a/Documentation/devicetree/bindings/mfd/max77693.txt
+++ b/Documentation/devicetree/bindings/mfd/max77693.txt
@@ -76,7 +76,60 @@ Optional properties:
     Valid values: 4300000, 4700000, 4800000, 4900000
     Default: 4300000
 
+- led : the LED submodule device node
+
+There are two LED outputs available - FLED1 and FLED2. Each of them can
+control a separate LED or they can be connected together to double
+the maximum current for a single connected LED. One LED is represented
+by one child node.
+
+Required properties:
+- compatible : Must be "maxim,max77693-led".
+
+Optional properties:
+- maxim,boost-mode :
+	In boost mode the device can produce up to 1.2A of total current
+	on both outputs. The maximum current on each output is reduced
+	to 625mA then. If not enabled explicitly, boost setting defaults to
+	LEDS_BOOST_FIXED in case both current sources are used.
+	Possible values:
+		LEDS_BOOST_OFF (0) - no boost,
+		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,
+		LEDS_BOOST_FIXED (2) - fixed mode.
+- maxim,boost-mvout : Output voltage of the boost module in millivolts.
+	Valid values: 3300 - 5500, step by 25 (rounded down)
+	Default: 3300
+- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired
+	if chip estimates that system voltage could drop below this level due
+	to flash power consumption.
+	Valid values: 2400 - 3400, step by 33 (rounded down)
+	Default: 2400
+
+Required properties for the LED child node:
+- led-sources : see Documentation/devicetree/bindings/leds/common.txt;
+		device current output identifiers: 0 - FLED1, 1 - FLED2
+- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+	Valid values for a LED connected to one FLED output:
+		15625 - 250000, step by 15625 (rounded down)
+	Valid values for a LED connected to both FLED outputs:
+		15625 - 500000, step by 15625 (rounded down)
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+	Valid values for a single LED connected to one FLED output
+	(boost mode must be turned off):
+		15625 - 1000000, step by 15625 (rounded down)
+	Valid values for a single LED connected to both FLED outputs:
+		15625 - 1250000, step by 15625 (rounded down)
+	Valid values for two LEDs case:
+		15625 - 625000, step by 15625 (rounded down)
+- flash-max-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+	Valid values: 62500 - 1000000, step by 62500 (rounded down)
+
+Optional properties for the LED child node:
+- label : see Documentation/devicetree/bindings/leds/common.txt
+
 Example:
+#include <dt-bindings/leds/common.h>
+
 	max77693@66 {
 		compatible = "maxim,max77693";
 		reg = <0x66>;
@@ -117,5 +170,19 @@ Example:
 			maxim,thermal-regulation-celsius = <75>;
 			maxim,battery-overcurrent-microamp = <3000000>;
 			maxim,charge-input-threshold-microvolt = <4300000>;
+
+		led {
+			compatible = "maxim,max77693-led";
+			maxim,boost-mode = <LEDS_BOOST_FIXED>;
+			maxim,boost-mvout = <5000>;
+			maxim,mvsys-min = <2400>;
+
+			camera_flash: flash-led {
+				label = "max77693-flash";
+				led-sources = <0>, <1>;
+				led-max-microamp = <500000>;
+				flash-max-microamp = <1250000>;
+				flash-max-timeout-us = <1000000>;
+			};
 		};
 	};
-- 
1.7.9.5

Re: [PATCH v6 02/10] DT: Add documentation for the mfd Maxim max77693

[Lee Jones]

On Tue, 28 Apr 2015, Jacek Anaszewski wrote:

> This patch adds device tree binding documentation for
> the flash cell of the Maxim max77693 multifunctional device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Signed-off-by: Andrzej Hajda <a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Acked-by: Kyungmin Park <kyungmin.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Acked-by: Sakari Ailus <sakari.ailus-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> Cc: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Chanwoo Choi <cw00.choi-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Cc: Bryan Wu <cooloney-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Richard Purdie <rpurdie-Fm38FmjxZ/leoWH0uzbU5w@public.gmane.org>
> Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> ---
>  Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++++++++++++++++++++
>  1 file changed, 67 insertions(+)

Requires a LED Ack.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
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Re: [PATCH v6 02/10] DT: Add documentation for the mfd Maxim max77693

[Lee Jones]

On Tue, 28 Apr 2015, Jacek Anaszewski wrote:

> This patch adds device tree binding documentation for
> the flash cell of the Maxim max77693 multifunctional device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Chanwoo Choi <cw00.choi@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: devicetree@vger.kernel.org
> ---
>  Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++++++++++++++++++++
>  1 file changed, 67 insertions(+)

Requires a LED Ack.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v6 02/10] DT: Add documentation for the mfd Maxim max77693

[Bryan Wu]

On Tue, Apr 28, 2015 at 3:09 AM, Lee Jones <lee.jones@linaro.org> wrote:
> On Tue, 28 Apr 2015, Jacek Anaszewski wrote:
>
>> This patch adds device tree binding documentation for
>> the flash cell of the Maxim max77693 multifunctional device.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>> Cc: Lee Jones <lee.jones@linaro.org>
>> Cc: Chanwoo Choi <cw00.choi@samsung.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>> Cc: devicetree@vger.kernel.org
>> ---
>>  Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++++++++++++++++++++
>>  1 file changed, 67 insertions(+)
>
> Requires a LED Ack.
>

Please go with my Ack:

Acked-by: Bryan Wu <cooloney@gmail.com>

Thanks,
-Bryan

Re: [PATCH v6 02/10] DT: Add documentation for the mfd Maxim max77693

[Lee Jones]

On Tue, 28 Apr 2015, Jacek Anaszewski wrote:

> This patch adds device tree binding documentation for
> the flash cell of the Maxim max77693 multifunctional device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Chanwoo Choi <cw00.choi@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: devicetree@vger.kernel.org
> ---
>  Documentation/devicetree/bindings/mfd/max77693.txt |   67 ++++++++++++++++++++
>  1 file changed, 67 insertions(+)

Applied with Bryan's Ack.

> diff --git a/Documentation/devicetree/bindings/mfd/max77693.txt b/Documentation/devicetree/bindings/mfd/max77693.txt
> index 38e6440..d342584 100644
> --- a/Documentation/devicetree/bindings/mfd/max77693.txt
> +++ b/Documentation/devicetree/bindings/mfd/max77693.txt
> @@ -76,7 +76,60 @@ Optional properties:
>      Valid values: 4300000, 4700000, 4800000, 4900000
>      Default: 4300000
>  
> +- led : the LED submodule device node
> +
> +There are two LED outputs available - FLED1 and FLED2. Each of them can
> +control a separate LED or they can be connected together to double
> +the maximum current for a single connected LED. One LED is represented
> +by one child node.
> +
> +Required properties:
> +- compatible : Must be "maxim,max77693-led".
> +
> +Optional properties:
> +- maxim,boost-mode :
> +	In boost mode the device can produce up to 1.2A of total current
> +	on both outputs. The maximum current on each output is reduced
> +	to 625mA then. If not enabled explicitly, boost setting defaults to
> +	LEDS_BOOST_FIXED in case both current sources are used.
> +	Possible values:
> +		LEDS_BOOST_OFF (0) - no boost,
> +		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,
> +		LEDS_BOOST_FIXED (2) - fixed mode.
> +- maxim,boost-mvout : Output voltage of the boost module in millivolts.
> +	Valid values: 3300 - 5500, step by 25 (rounded down)
> +	Default: 3300
> +- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired
> +	if chip estimates that system voltage could drop below this level due
> +	to flash power consumption.
> +	Valid values: 2400 - 3400, step by 33 (rounded down)
> +	Default: 2400
> +
> +Required properties for the LED child node:
> +- led-sources : see Documentation/devicetree/bindings/leds/common.txt;
> +		device current output identifiers: 0 - FLED1, 1 - FLED2
> +- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +	Valid values for a LED connected to one FLED output:
> +		15625 - 250000, step by 15625 (rounded down)
> +	Valid values for a LED connected to both FLED outputs:
> +		15625 - 500000, step by 15625 (rounded down)
> +- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +	Valid values for a single LED connected to one FLED output
> +	(boost mode must be turned off):
> +		15625 - 1000000, step by 15625 (rounded down)
> +	Valid values for a single LED connected to both FLED outputs:
> +		15625 - 1250000, step by 15625 (rounded down)
> +	Valid values for two LEDs case:
> +		15625 - 625000, step by 15625 (rounded down)
> +- flash-max-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
> +	Valid values: 62500 - 1000000, step by 62500 (rounded down)
> +
> +Optional properties for the LED child node:
> +- label : see Documentation/devicetree/bindings/leds/common.txt
> +
>  Example:
> +#include <dt-bindings/leds/common.h>
> +
>  	max77693@66 {
>  		compatible = "maxim,max77693";
>  		reg = <0x66>;
> @@ -117,5 +170,19 @@ Example:
>  			maxim,thermal-regulation-celsius = <75>;
>  			maxim,battery-overcurrent-microamp = <3000000>;
>  			maxim,charge-input-threshold-microvolt = <4300000>;
> +
> +		led {
> +			compatible = "maxim,max77693-led";
> +			maxim,boost-mode = <LEDS_BOOST_FIXED>;
> +			maxim,boost-mvout = <5000>;
> +			maxim,mvsys-min = <2400>;
> +
> +			camera_flash: flash-led {
> +				label = "max77693-flash";
> +				led-sources = <0>, <1>;
> +				led-max-microamp = <500000>;
> +				flash-max-microamp = <1250000>;
> +				flash-max-timeout-us = <1000000>;
> +			};
>  		};
>  	};

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v6 03/10] leds: Add support for max77693 mfd flash cell

[Jacek Anaszewski]

This patch adds led-flash support to Maxim max77693 chipset.
A device can be exposed to user space through LED subsystem
sysfs interface. Device supports up to two leds which can
work in flash and torch mode. The leds can be triggered
externally or by software.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/leds/Kconfig         |   10 +
 drivers/leds/Makefile        |    1 +
 drivers/leds/leds-max77693.c |  988 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 999 insertions(+)
 create mode 100644 drivers/leds/leds-max77693.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a38b17a..62be033 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -475,6 +475,16 @@ config LEDS_TLC591XX
 	  This option enables support for Texas Instruments TLC59108
 	  and TLC59116 LED controllers.
 
+config LEDS_MAX77693
+	tristate "LED support for MAX77693 Flash"
+	depends on LEDS_CLASS_FLASH
+	depends on MFD_MAX77693
+	depends on OF
+	help
+	  This option enables support for the flash part of the MAX77693
+	  multifunction device. It has build in control for two leds in flash
+	  and torch mode.
+
 config LEDS_MAX8997
 	tristate "LED support for MAX8997 PMIC"
 	depends on LEDS_CLASS && MFD_MAX8997
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 749dbe3..8bddae6 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_LEDS_MC13783)		+= leds-mc13783.o
 obj-$(CONFIG_LEDS_NS2)			+= leds-ns2.o
 obj-$(CONFIG_LEDS_NETXBIG)		+= leds-netxbig.o
 obj-$(CONFIG_LEDS_ASIC3)		+= leds-asic3.o
+obj-$(CONFIG_LEDS_MAX77693)		+= leds-max77693.o
 obj-$(CONFIG_LEDS_MAX8997)		+= leds-max8997.o
 obj-$(CONFIG_LEDS_LM355x)		+= leds-lm355x.o
 obj-$(CONFIG_LEDS_BLINKM)		+= leds-blinkm.o
diff --git a/drivers/leds/leds-max77693.c b/drivers/leds/leds-max77693.c
new file mode 100644
index 0000000..0dd8cb0
--- /dev/null
+++ b/drivers/leds/leds-max77693.c
@@ -0,0 +1,988 @@
+/*
+ * LED Flash class driver for the flash cell of max77693 mfd.
+ *
+ *	Copyright (C) 2015, Samsung Electronics Co., Ltd.
+ *
+ *	Authors: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *		 Andrzej Hajda <a.hajda@samsung.com>
+ *
+ * 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/led-class-flash.h>
+#include <linux/mfd/max77693.h>
+#include <linux/mfd/max77693-private.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#define MODE_OFF		0
+#define MODE_FLASH(a)		(1 << (a))
+#define MODE_TORCH(a)		(1 << (2 + (a)))
+#define MODE_FLASH_EXTERNAL(a)	(1 << (4 + (a)))
+
+#define MODE_FLASH_MASK		(MODE_FLASH(FLED1) | MODE_FLASH(FLED2) | \
+				 MODE_FLASH_EXTERNAL(FLED1) | \
+				 MODE_FLASH_EXTERNAL(FLED2))
+#define MODE_TORCH_MASK		(MODE_TORCH(FLED1) | MODE_TORCH(FLED2))
+
+#define FLED1_IOUT		(1 << 0)
+#define FLED2_IOUT		(1 << 1)
+
+enum max77693_fled {
+	FLED1,
+	FLED2,
+};
+
+enum max77693_led_mode {
+	FLASH,
+	TORCH,
+};
+
+struct max77693_led_config_data {
+	const char *label[2];
+	u32 iout_torch_max[2];
+	u32 iout_flash_max[2];
+	u32 flash_timeout_max[2];
+	u32 num_leds;
+	u32 boost_mode;
+	u32 boost_vout;
+	u32 low_vsys;
+};
+
+struct max77693_sub_led {
+	/* corresponding FLED output identifier */
+	int fled_id;
+	/* corresponding LED Flash class device */
+	struct led_classdev_flash fled_cdev;
+	/* assures led-triggers compatibility */
+	struct work_struct work_brightness_set;
+
+	/* brightness cache */
+	unsigned int torch_brightness;
+	/* flash timeout cache */
+	unsigned int flash_timeout;
+	/* flash faults that may have occurred */
+	u32 flash_faults;
+};
+
+struct max77693_led_device {
+	/* parent mfd regmap */
+	struct regmap *regmap;
+	/* platform device data */
+	struct platform_device *pdev;
+	/* secures access to the device */
+	struct mutex lock;
+
+	/* sub led data */
+	struct max77693_sub_led sub_leds[2];
+
+	/* maximum torch current values for FLED outputs */
+	u32 iout_torch_max[2];
+	/* maximum flash current values for FLED outputs */
+	u32 iout_flash_max[2];
+
+	/* current flash timeout cache */
+	unsigned int current_flash_timeout;
+	/* ITORCH register cache */
+	u8 torch_iout_reg;
+	/* mode of fled outputs */
+	unsigned int mode_flags;
+	/* recently strobed fled */
+	int strobing_sub_led_id;
+	/* bitmask of FLED outputs use state (bit 0. - FLED1, bit 1. - FLED2) */
+	u8 fled_mask;
+	/* FLED modes that can be set */
+	u8 allowed_modes;
+
+	/* arrangement of current outputs */
+	bool iout_joint;
+};
+
+static u8 max77693_led_iout_to_reg(u32 ua)
+{
+	if (ua < FLASH_IOUT_MIN)
+		ua = FLASH_IOUT_MIN;
+	return (ua - FLASH_IOUT_MIN) / FLASH_IOUT_STEP;
+}
+
+static u8 max77693_flash_timeout_to_reg(u32 us)
+{
+	return (us - FLASH_TIMEOUT_MIN) / FLASH_TIMEOUT_STEP;
+}
+
+static inline struct max77693_sub_led *flcdev_to_sub_led(
+					struct led_classdev_flash *fled_cdev)
+{
+	return container_of(fled_cdev, struct max77693_sub_led, fled_cdev);
+}
+
+static inline struct max77693_led_device *sub_led_to_led(
+					struct max77693_sub_led *sub_led)
+{
+	return container_of(sub_led, struct max77693_led_device,
+				sub_leds[sub_led->fled_id]);
+}
+
+static inline u8 max77693_led_vsys_to_reg(u32 mv)
+{
+	return ((mv - MAX_FLASH1_VSYS_MIN) / MAX_FLASH1_VSYS_STEP) << 2;
+}
+
+static inline u8 max77693_led_vout_to_reg(u32 mv)
+{
+	return (mv - FLASH_VOUT_MIN) / FLASH_VOUT_STEP + FLASH_VOUT_RMIN;
+}
+
+static inline bool max77693_fled_used(struct max77693_led_device *led,
+					 int fled_id)
+{
+	u8 fled_bit = (fled_id == FLED1) ? FLED1_IOUT : FLED2_IOUT;
+
+	return led->fled_mask & fled_bit;
+}
+
+static int max77693_set_mode_reg(struct max77693_led_device *led, u8 mode)
+{
+	struct regmap *rmap = led->regmap;
+	int ret, v = 0, i;
+
+	for (i = FLED1; i <= FLED2; ++i) {
+		if (mode & MODE_TORCH(i))
+			v |= FLASH_EN_ON << TORCH_EN_SHIFT(i);
+
+		if (mode & MODE_FLASH(i)) {
+			v |= FLASH_EN_ON << FLASH_EN_SHIFT(i);
+		} else if (mode & MODE_FLASH_EXTERNAL(i)) {
+			v |= FLASH_EN_FLASH << FLASH_EN_SHIFT(i);
+			/*
+			 * Enable hw triggering also for torch mode, as some
+			 * camera sensors use torch led to fathom ambient light
+			 * conditions before strobing the flash.
+			 */
+			v |= FLASH_EN_TORCH << TORCH_EN_SHIFT(i);
+		}
+	}
+
+	/* Reset the register only prior setting flash modes */
+	if (mode & ~(MODE_TORCH(FLED1) | MODE_TORCH(FLED2))) {
+		ret = regmap_write(rmap, MAX77693_LED_REG_FLASH_EN, 0);
+		if (ret < 0)
+			return ret;
+	}
+
+	return regmap_write(rmap, MAX77693_LED_REG_FLASH_EN, v);
+}
+
+static int max77693_add_mode(struct max77693_led_device *led, u8 mode)
+{
+	int i, ret;
+
+	mode &= led->allowed_modes;
+
+	/*
+	 * Torch mode once enabled remains active until turned off. If the FLED2
+	 * output isn't to be disabled check if the torch mode to be set isn't
+	 * already activated and avoid re-setting it.
+	 */
+	if ((!(mode ^ led->mode_flags)) & MODE_TORCH(FLED2)) {
+		for (i = FLED1; i <= FLED2; ++i)
+			if ((mode & led->mode_flags & MODE_TORCH(i)))
+				return 0;
+	}
+
+	if (led->iout_joint)
+		/* Span the mode on FLED2 for joint iouts case */
+		mode |= (mode << 1);
+
+	/*
+	 * FLASH_EXTERNAL mode activates FLASHEN and TORCHEN pins in the device.
+	 * Corresponding register bit fields interfere with SW triggered modes,
+	 * thus clear them to ensure proper device configuration.
+	 */
+	for (i = FLED1; i <= FLED2; ++i)
+		if (mode & MODE_FLASH_EXTERNAL(i))
+			led->mode_flags &= (~MODE_TORCH(i) & ~MODE_FLASH(i));
+
+	led->mode_flags |= mode;
+	led->mode_flags &= led->allowed_modes;
+
+	ret = max77693_set_mode_reg(led, led->mode_flags);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Clear flash mode flag after setting the mode to avoid spurious flash
+	 * strobing on each subsequent torch mode setting.
+	 */
+	if (mode & MODE_FLASH_MASK)
+		led->mode_flags &= ~mode;
+
+	return ret;
+}
+
+static int max77693_clear_mode(struct max77693_led_device *led,
+				u8 mode)
+{
+	if (led->iout_joint)
+		/* Clear mode also on FLED2 for joint iouts case */
+		mode |= (mode << 1);
+
+	led->mode_flags &= ~mode;
+
+	return max77693_set_mode_reg(led, led->mode_flags);
+}
+
+static void max77693_add_allowed_modes(struct max77693_led_device *led,
+				int fled_id, enum max77693_led_mode mode)
+{
+	if (mode == FLASH)
+		led->allowed_modes |= (MODE_FLASH(fled_id) |
+				       MODE_FLASH_EXTERNAL(fled_id));
+	else
+		led->allowed_modes |= MODE_TORCH(fled_id);
+}
+
+static void max77693_distribute_currents(struct max77693_led_device *led,
+				int fled_id, enum max77693_led_mode mode,
+				u32 micro_amp, u32 iout_max[2], u32 iout[2])
+{
+	if (!led->iout_joint) {
+		iout[fled_id] = micro_amp;
+		max77693_add_allowed_modes(led, fled_id, mode);
+		return;
+	}
+
+	iout[FLED1] = min(micro_amp, iout_max[FLED1]);
+	iout[FLED2] = micro_amp - iout[FLED1];
+
+	if (mode == FLASH)
+		led->allowed_modes &= ~MODE_FLASH_MASK;
+	else
+		led->allowed_modes &= ~MODE_TORCH_MASK;
+
+	max77693_add_allowed_modes(led, FLED1, mode);
+
+	if (iout[FLED2])
+		max77693_add_allowed_modes(led, FLED2, mode);
+}
+
+static int max77693_set_torch_current(struct max77693_led_device *led,
+				int fled_id, u32 micro_amp)
+{
+	struct regmap *rmap = led->regmap;
+	u8 iout1_reg = 0, iout2_reg = 0;
+	u32 iout[2];
+
+	max77693_distribute_currents(led, fled_id, TORCH, micro_amp,
+					led->iout_torch_max, iout);
+
+	if (fled_id == FLED1 || led->iout_joint) {
+		iout1_reg = max77693_led_iout_to_reg(iout[FLED1]);
+		led->torch_iout_reg &= TORCH_IOUT_MASK(TORCH_IOUT2_SHIFT);
+	}
+	if (fled_id == FLED2 || led->iout_joint) {
+		iout2_reg = max77693_led_iout_to_reg(iout[FLED2]);
+		led->torch_iout_reg &= TORCH_IOUT_MASK(TORCH_IOUT1_SHIFT);
+	}
+
+	led->torch_iout_reg |= ((iout1_reg << TORCH_IOUT1_SHIFT) |
+				(iout2_reg << TORCH_IOUT2_SHIFT));
+
+	return regmap_write(rmap, MAX77693_LED_REG_ITORCH,
+						led->torch_iout_reg);
+}
+
+static int max77693_set_flash_current(struct max77693_led_device *led,
+					int fled_id,
+					u32 micro_amp)
+{
+	struct regmap *rmap = led->regmap;
+	u8 iout1_reg, iout2_reg;
+	u32 iout[2];
+	int ret = -EINVAL;
+
+	max77693_distribute_currents(led, fled_id, FLASH, micro_amp,
+					led->iout_flash_max, iout);
+
+	if (fled_id == FLED1 || led->iout_joint) {
+		iout1_reg = max77693_led_iout_to_reg(iout[FLED1]);
+		ret = regmap_write(rmap, MAX77693_LED_REG_IFLASH1,
+							iout1_reg);
+		if (ret < 0)
+			return ret;
+	}
+	if (fled_id == FLED2 || led->iout_joint) {
+		iout2_reg = max77693_led_iout_to_reg(iout[FLED2]);
+		ret = regmap_write(rmap, MAX77693_LED_REG_IFLASH2,
+							iout2_reg);
+	}
+
+	return ret;
+}
+
+static int max77693_set_timeout(struct max77693_led_device *led, u32 microsec)
+{
+	struct regmap *rmap = led->regmap;
+	u8 v;
+	int ret;
+
+	v = max77693_flash_timeout_to_reg(microsec) | FLASH_TMR_LEVEL;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_FLASH_TIMER, v);
+	if (ret < 0)
+		return ret;
+
+	led->current_flash_timeout = microsec;
+
+	return 0;
+}
+
+static int max77693_get_strobe_status(struct max77693_led_device *led,
+					bool *state)
+{
+	struct regmap *rmap = led->regmap;
+	unsigned int v;
+	int ret;
+
+	ret = regmap_read(rmap, MAX77693_LED_REG_FLASH_STATUS, &v);
+	if (ret < 0)
+		return ret;
+
+	*state = v & FLASH_STATUS_FLASH_ON;
+
+	return ret;
+}
+
+static int max77693_get_flash_faults(struct max77693_sub_led *sub_led)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	struct regmap *rmap = led->regmap;
+	unsigned int v;
+	u8 fault_open_mask, fault_short_mask;
+	int ret;
+
+	sub_led->flash_faults = 0;
+
+	if (led->iout_joint) {
+		fault_open_mask = FLASH_INT_FLED1_OPEN | FLASH_INT_FLED2_OPEN;
+		fault_short_mask = FLASH_INT_FLED1_SHORT |
+							FLASH_INT_FLED2_SHORT;
+	} else {
+		fault_open_mask = (sub_led->fled_id == FLED1) ?
+						FLASH_INT_FLED1_OPEN :
+						FLASH_INT_FLED2_OPEN;
+		fault_short_mask = (sub_led->fled_id == FLED1) ?
+						FLASH_INT_FLED1_SHORT :
+						FLASH_INT_FLED2_SHORT;
+	}
+
+	ret = regmap_read(rmap, MAX77693_LED_REG_FLASH_INT, &v);
+	if (ret < 0)
+		return ret;
+
+	if (v & fault_open_mask)
+		sub_led->flash_faults |= LED_FAULT_OVER_VOLTAGE;
+	if (v & fault_short_mask)
+		sub_led->flash_faults |= LED_FAULT_SHORT_CIRCUIT;
+	if (v & FLASH_INT_OVER_CURRENT)
+		sub_led->flash_faults |= LED_FAULT_OVER_CURRENT;
+
+	return 0;
+}
+
+static int max77693_setup(struct max77693_led_device *led,
+			 struct max77693_led_config_data *led_cfg)
+{
+	struct regmap *rmap = led->regmap;
+	int i, first_led, last_led, ret;
+	u32 max_flash_curr[2];
+	u8 v;
+
+	/*
+	 * Initialize only flash current. Torch current doesn't
+	 * require initialization as ITORCH register is written with
+	 * new value each time brightness_set op is called.
+	 */
+	if (led->iout_joint) {
+		first_led = FLED1;
+		last_led = FLED1;
+		max_flash_curr[FLED1] = led_cfg->iout_flash_max[FLED1] +
+					led_cfg->iout_flash_max[FLED2];
+	} else {
+		first_led = max77693_fled_used(led, FLED1) ? FLED1 : FLED2;
+		last_led = max77693_fled_used(led, FLED2) ? FLED2 : FLED1;
+		max_flash_curr[FLED1] = led_cfg->iout_flash_max[FLED1];
+		max_flash_curr[FLED2] = led_cfg->iout_flash_max[FLED2];
+	}
+
+	for (i = first_led; i <= last_led; ++i) {
+		ret = max77693_set_flash_current(led, i,
+					max_flash_curr[i]);
+		if (ret < 0)
+			return ret;
+	}
+
+	v = TORCH_TMR_NO_TIMER | MAX77693_LED_TRIG_TYPE_LEVEL;
+	ret = regmap_write(rmap, MAX77693_LED_REG_ITORCHTIMER, v);
+	if (ret < 0)
+		return ret;
+
+	if (led_cfg->low_vsys > 0)
+		v = max77693_led_vsys_to_reg(led_cfg->low_vsys) |
+						MAX_FLASH1_MAX_FL_EN;
+	else
+		v = 0;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_MAX_FLASH1, v);
+	if (ret < 0)
+		return ret;
+	ret = regmap_write(rmap, MAX77693_LED_REG_MAX_FLASH2, 0);
+	if (ret < 0)
+		return ret;
+
+	if (led_cfg->boost_mode == MAX77693_LED_BOOST_FIXED)
+		v = FLASH_BOOST_FIXED;
+	else
+		v = led_cfg->boost_mode | led_cfg->boost_mode << 1;
+
+	if (max77693_fled_used(led, FLED1) && max77693_fled_used(led, FLED2))
+		v |= FLASH_BOOST_LEDNUM_2;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_VOUT_CNTL, v);
+	if (ret < 0)
+		return ret;
+
+	v = max77693_led_vout_to_reg(led_cfg->boost_vout);
+	ret = regmap_write(rmap, MAX77693_LED_REG_VOUT_FLASH1, v);
+	if (ret < 0)
+		return ret;
+
+	return max77693_set_mode_reg(led, MODE_OFF);
+}
+
+static int __max77693_led_brightness_set(struct max77693_led_device *led,
+					int fled_id, enum led_brightness value)
+{
+	int ret;
+
+	mutex_lock(&led->lock);
+
+	if (value == 0) {
+		ret = max77693_clear_mode(led, MODE_TORCH(fled_id));
+		if (ret < 0)
+			dev_dbg(&led->pdev->dev,
+				"Failed to clear torch mode (%d)\n",
+				ret);
+		goto unlock;
+	}
+
+	ret = max77693_set_torch_current(led, fled_id, value * TORCH_IOUT_STEP);
+	if (ret < 0) {
+		dev_dbg(&led->pdev->dev,
+			"Failed to set torch current (%d)\n",
+			ret);
+		goto unlock;
+	}
+
+	ret = max77693_add_mode(led, MODE_TORCH(fled_id));
+	if (ret < 0)
+		dev_dbg(&led->pdev->dev,
+			"Failed to set torch mode (%d)\n",
+			ret);
+unlock:
+	mutex_unlock(&led->lock);
+	return ret;
+}
+
+static void max77693_led_brightness_set_work(
+					struct work_struct *work)
+{
+	struct max77693_sub_led *sub_led =
+			container_of(work, struct max77693_sub_led,
+					work_brightness_set);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	__max77693_led_brightness_set(led, sub_led->fled_id,
+				sub_led->torch_brightness);
+}
+
+/* LED subsystem callbacks */
+
+static int max77693_led_brightness_set_sync(
+				struct led_classdev *led_cdev,
+				enum led_brightness value)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	return __max77693_led_brightness_set(led, sub_led->fled_id, value);
+}
+
+static void max77693_led_brightness_set(
+				struct led_classdev *led_cdev,
+				enum led_brightness value)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+
+	sub_led->torch_brightness = value;
+	schedule_work(&sub_led->work_brightness_set);
+}
+
+static int max77693_led_flash_brightness_set(
+				struct led_classdev_flash *fled_cdev,
+				u32 brightness)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int ret;
+
+	mutex_lock(&led->lock);
+	ret = max77693_set_flash_current(led, sub_led->fled_id, brightness);
+	mutex_unlock(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_flash_strobe_set(
+				struct led_classdev_flash *fled_cdev,
+				bool state)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	int ret;
+
+	mutex_lock(&led->lock);
+
+	if (!state) {
+		ret = max77693_clear_mode(led, MODE_FLASH(fled_id));
+		goto unlock;
+	}
+
+	if (sub_led->flash_timeout != led->current_flash_timeout) {
+		ret = max77693_set_timeout(led, sub_led->flash_timeout);
+		if (ret < 0)
+			goto unlock;
+	}
+
+	led->strobing_sub_led_id = fled_id;
+
+	ret = max77693_add_mode(led, MODE_FLASH(fled_id));
+	if (ret < 0)
+		goto unlock;
+
+	ret = max77693_get_flash_faults(sub_led);
+
+unlock:
+	mutex_unlock(&led->lock);
+	return ret;
+}
+
+static int max77693_led_flash_fault_get(
+				struct led_classdev_flash *fled_cdev,
+				u32 *fault)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+
+	*fault = sub_led->flash_faults;
+
+	return 0;
+}
+
+static int max77693_led_flash_strobe_get(
+				struct led_classdev_flash *fled_cdev,
+				bool *state)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int ret;
+
+	if (!state)
+		return -EINVAL;
+
+	mutex_lock(&led->lock);
+
+	ret = max77693_get_strobe_status(led, state);
+
+	*state = !!(*state && (led->strobing_sub_led_id == sub_led->fled_id));
+
+	mutex_unlock(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_flash_timeout_set(
+				struct led_classdev_flash *fled_cdev,
+				u32 timeout)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	mutex_lock(&led->lock);
+	sub_led->flash_timeout = timeout;
+	mutex_unlock(&led->lock);
+
+	return 0;
+}
+
+static int max77693_led_parse_dt(struct max77693_led_device *led,
+				struct max77693_led_config_data *cfg)
+{
+	struct device *dev = &led->pdev->dev;
+	struct max77693_sub_led *sub_leds = led->sub_leds;
+	struct device_node *node = dev->of_node, *child_node;
+	struct property *prop;
+	u32 led_sources[2];
+	int i, ret, fled_id;
+
+	of_property_read_u32(node, "maxim,boost-mode", &cfg->boost_mode);
+	of_property_read_u32(node, "maxim,boost-mvout", &cfg->boost_vout);
+	of_property_read_u32(node, "maxim,mvsys-min", &cfg->low_vsys);
+
+	for_each_available_child_of_node(node, child_node) {
+		prop = of_find_property(child_node, "led-sources", NULL);
+		if (prop) {
+			const __be32 *srcs = NULL;
+
+			for (i = 0; i < ARRAY_SIZE(led_sources); ++i) {
+				srcs = of_prop_next_u32(prop, srcs,
+							&led_sources[i]);
+				if (!srcs)
+					break;
+			}
+		} else {
+			dev_err(dev,
+				"led-sources DT property missing\n");
+			of_node_put(child_node);
+			return -EINVAL;
+		}
+
+		if (i == 2) {
+			fled_id = FLED1;
+			led->fled_mask = FLED1_IOUT | FLED2_IOUT;
+		} else if (led_sources[0] == FLED1) {
+			fled_id = FLED1;
+			led->fled_mask |= FLED1_IOUT;
+		} else if (led_sources[0] == FLED2) {
+			fled_id = FLED2;
+			led->fled_mask |= FLED2_IOUT;
+		} else {
+			dev_err(dev,
+				"Wrong led-sources DT property value.\n");
+			of_node_put(child_node);
+			return -EINVAL;
+		}
+
+		sub_leds[fled_id].fled_id = fled_id;
+
+		cfg->label[fled_id] =
+			of_get_property(child_node, "label", NULL) ? :
+						child_node->name;
+
+		ret = of_property_read_u32(child_node, "led-max-microamp",
+					&cfg->iout_torch_max[fled_id]);
+		if (ret < 0) {
+			cfg->iout_torch_max[fled_id] = TORCH_IOUT_MIN;
+			dev_warn(dev, "led-max-microamp DT property missing\n");
+		}
+
+		ret = of_property_read_u32(child_node, "flash-max-microamp",
+					&cfg->iout_flash_max[fled_id]);
+		if (ret < 0) {
+			cfg->iout_flash_max[fled_id] = FLASH_IOUT_MIN;
+			dev_warn(dev,
+				 "flash-max-microamp DT property missing\n");
+		}
+
+		ret = of_property_read_u32(child_node, "flash-max-timeout-us",
+					&cfg->flash_timeout_max[fled_id]);
+		if (ret < 0) {
+			cfg->flash_timeout_max[fled_id] = FLASH_TIMEOUT_MIN;
+			dev_warn(dev,
+				 "flash-max-timeout-us DT property missing\n");
+		}
+
+		if (++cfg->num_leds == 2 ||
+		    (max77693_fled_used(led, FLED1) &&
+		     max77693_fled_used(led, FLED2))) {
+			of_node_put(child_node);
+			break;
+		}
+	}
+
+	if (cfg->num_leds == 0) {
+		dev_err(dev, "No DT child node found for connected LED(s).\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
+{
+	*v = clamp_val(*v, min, max);
+	if (step > 1)
+		*v = (*v - min) / step * step + min;
+}
+
+static void max77693_align_iout_current(struct max77693_led_device *led,
+					u32 *iout, u32 min, u32 max, u32 step)
+{
+	int i;
+
+	if (led->iout_joint) {
+		if (iout[FLED1] > min) {
+			iout[FLED1] /= 2;
+			iout[FLED2] = iout[FLED1];
+		} else {
+			iout[FLED1] = min;
+			iout[FLED2] = 0;
+			return;
+		}
+	}
+
+	for (i = FLED1; i <= FLED2; ++i)
+		if (max77693_fled_used(led, i))
+			clamp_align(&iout[i], min, max, step);
+		else
+			iout[i] = 0;
+}
+
+static void max77693_led_validate_configuration(struct max77693_led_device *led,
+					struct max77693_led_config_data *cfg)
+{
+	u32 flash_iout_max = cfg->boost_mode ? FLASH_IOUT_MAX_2LEDS :
+					       FLASH_IOUT_MAX_1LED;
+	int i;
+
+	if (cfg->num_leds == 1 &&
+	    max77693_fled_used(led, FLED1) && max77693_fled_used(led, FLED2))
+		led->iout_joint = true;
+
+	cfg->boost_mode = clamp_val(cfg->boost_mode, MAX77693_LED_BOOST_NONE,
+			    MAX77693_LED_BOOST_FIXED);
+
+	/* Boost must be enabled if both current outputs are used */
+	if ((cfg->boost_mode == MAX77693_LED_BOOST_NONE) && led->iout_joint)
+		cfg->boost_mode = MAX77693_LED_BOOST_FIXED;
+
+	max77693_align_iout_current(led, cfg->iout_torch_max,
+			TORCH_IOUT_MIN, TORCH_IOUT_MAX, TORCH_IOUT_STEP);
+
+	max77693_align_iout_current(led, cfg->iout_flash_max,
+			FLASH_IOUT_MIN, flash_iout_max, FLASH_IOUT_STEP);
+
+	for (i = 0; i < ARRAY_SIZE(cfg->flash_timeout_max); ++i)
+		clamp_align(&cfg->flash_timeout_max[i], FLASH_TIMEOUT_MIN,
+				FLASH_TIMEOUT_MAX, FLASH_TIMEOUT_STEP);
+
+	clamp_align(&cfg->boost_vout, FLASH_VOUT_MIN, FLASH_VOUT_MAX,
+							FLASH_VOUT_STEP);
+
+	if (cfg->low_vsys)
+		clamp_align(&cfg->low_vsys, MAX_FLASH1_VSYS_MIN,
+				MAX_FLASH1_VSYS_MAX, MAX_FLASH1_VSYS_STEP);
+}
+
+static int max77693_led_get_configuration(struct max77693_led_device *led,
+				struct max77693_led_config_data *cfg)
+{
+	int ret;
+
+	ret = max77693_led_parse_dt(led, cfg);
+	if (ret < 0)
+		return ret;
+
+	max77693_led_validate_configuration(led, cfg);
+
+	memcpy(led->iout_torch_max, cfg->iout_torch_max,
+				sizeof(led->iout_torch_max));
+	memcpy(led->iout_flash_max, cfg->iout_flash_max,
+				sizeof(led->iout_flash_max));
+
+	return 0;
+}
+
+static const struct led_flash_ops flash_ops = {
+	.flash_brightness_set	= max77693_led_flash_brightness_set,
+	.strobe_set		= max77693_led_flash_strobe_set,
+	.strobe_get		= max77693_led_flash_strobe_get,
+	.timeout_set		= max77693_led_flash_timeout_set,
+	.fault_get		= max77693_led_flash_fault_get,
+};
+
+static void max77693_init_flash_settings(struct max77693_sub_led *sub_led,
+				 struct max77693_led_config_data *led_cfg)
+{
+	struct led_classdev_flash *fled_cdev = &sub_led->fled_cdev;
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	struct led_flash_setting *setting;
+
+	/* Init flash intensity setting */
+	setting = &fled_cdev->brightness;
+	setting->min = FLASH_IOUT_MIN;
+	setting->max = led->iout_joint ?
+		led_cfg->iout_flash_max[FLED1] +
+		led_cfg->iout_flash_max[FLED2] :
+		led_cfg->iout_flash_max[fled_id];
+	setting->step = FLASH_IOUT_STEP;
+	setting->val = setting->max;
+
+	/* Init flash timeout setting */
+	setting = &fled_cdev->timeout;
+	setting->min = FLASH_TIMEOUT_MIN;
+	setting->max = led_cfg->flash_timeout_max[fled_id];
+	setting->step = FLASH_TIMEOUT_STEP;
+	setting->val = setting->max;
+}
+
+static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
+				struct max77693_led_config_data *led_cfg)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	struct led_classdev_flash *fled_cdev;
+	struct led_classdev *led_cdev;
+
+	/* Initialize LED Flash class device */
+	fled_cdev = &sub_led->fled_cdev;
+	fled_cdev->ops = &flash_ops;
+	led_cdev = &fled_cdev->led_cdev;
+
+	led_cdev->name = led_cfg->label[fled_id];
+
+	led_cdev->brightness_set = max77693_led_brightness_set;
+	led_cdev->brightness_set_sync = max77693_led_brightness_set_sync;
+	led_cdev->max_brightness = (led->iout_joint ?
+					led_cfg->iout_torch_max[FLED1] +
+					led_cfg->iout_torch_max[FLED2] :
+					led_cfg->iout_torch_max[fled_id]) /
+				   TORCH_IOUT_STEP;
+	led_cdev->flags |= LED_DEV_CAP_FLASH;
+	INIT_WORK(&sub_led->work_brightness_set,
+			max77693_led_brightness_set_work);
+
+	max77693_init_flash_settings(sub_led, led_cfg);
+
+	/* Init flash timeout cache */
+	sub_led->flash_timeout = fled_cdev->timeout.val;
+}
+
+static int max77693_led_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
+	struct max77693_led_device *led;
+	struct max77693_sub_led *sub_leds;
+	struct max77693_led_config_data led_cfg = {};
+	int init_fled_cdev[2], i, ret;
+
+	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
+	if (!led)
+		return -ENOMEM;
+
+	led->pdev = pdev;
+	led->regmap = iodev->regmap;
+	led->allowed_modes = MODE_FLASH_MASK;
+	sub_leds = led->sub_leds;
+
+	platform_set_drvdata(pdev, led);
+	ret = max77693_led_get_configuration(led, &led_cfg);
+	if (ret < 0)
+		return ret;
+
+	ret = max77693_setup(led, &led_cfg);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&led->lock);
+
+	init_fled_cdev[FLED1] =
+			led->iout_joint || max77693_fled_used(led, FLED1);
+	init_fled_cdev[FLED2] =
+			!led->iout_joint && max77693_fled_used(led, FLED2);
+
+	for (i = FLED1; i <= FLED2; ++i) {
+		if (!init_fled_cdev[i])
+			continue;
+
+		/* Initialize LED Flash class device */
+		max77693_init_fled_cdev(&sub_leds[i], &led_cfg);
+
+		/* Register LED Flash class device */
+		ret = led_classdev_flash_register(dev, &sub_leds[i].fled_cdev);
+		if (ret < 0) {
+			/*
+			 * At this moment FLED1 might have been already
+			 * registered and it needs to be released.
+			 */
+			if (i == FLED2)
+				goto err_register_led2;
+			else
+				goto err_register_led1;
+		}
+	}
+
+	return 0;
+
+err_register_led2:
+	/* It is possible than only FLED2 was to be registered */
+	if (!init_fled_cdev[FLED1])
+		goto err_register_led1;
+	led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
+err_register_led1:
+	mutex_destroy(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_remove(struct platform_device *pdev)
+{
+	struct max77693_led_device *led = platform_get_drvdata(pdev);
+	struct max77693_sub_led *sub_leds = led->sub_leds;
+
+	if (led->iout_joint || max77693_fled_used(led, FLED1)) {
+		led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
+		cancel_work_sync(&sub_leds[FLED1].work_brightness_set);
+	}
+
+	if (!led->iout_joint && max77693_fled_used(led, FLED2)) {
+		led_classdev_flash_unregister(&sub_leds[FLED2].fled_cdev);
+		cancel_work_sync(&sub_leds[FLED2].work_brightness_set);
+	}
+
+	mutex_destroy(&led->lock);
+
+	return 0;
+}
+
+static const struct of_device_id max77693_led_dt_match[] = {
+	{ .compatible = "maxim,max77693-led" },
+	{},
+};
+
+static struct platform_driver max77693_led_driver = {
+	.probe		= max77693_led_probe,
+	.remove		= max77693_led_remove,
+	.driver		= {
+		.name	= "max77693-led",
+		.owner	= THIS_MODULE,
+		.of_match_table = max77693_led_dt_match,
+	},
+};
+
+module_platform_driver(max77693_led_driver);
+
+MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
+MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
+MODULE_DESCRIPTION("Maxim MAX77693 led flash driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5

Re: [PATCH v6 03/10] leds: Add support for max77693 mfd flash cell

[Sakari Ailus]

Hi Jacek,

On Tue, Apr 28, 2015 at 09:18:43AM +0200, Jacek Anaszewski wrote:
> This patch adds led-flash support to Maxim max77693 chipset.
> A device can be exposed to user space through LED subsystem
> sysfs interface. Device supports up to two leds which can
> work in flash and torch mode. The leds can be triggered
> externally or by software.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Chanwoo Choi <cw00.choi@samsung.com>

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

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

Re: [PATCH v6 03/10] leds: Add support for max77693 mfd flash cell

[Bryan Wu]

On Tue, Apr 28, 2015 at 4:36 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote:
> Hi Jacek,
>
> On Tue, Apr 28, 2015 at 09:18:43AM +0200, Jacek Anaszewski wrote:
>> This patch adds led-flash support to Maxim max77693 chipset.
>> A device can be exposed to user space through LED subsystem
>> sysfs interface. Device supports up to two leds which can
>> work in flash and torch mode. The leds can be triggered
>> externally or by software.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>> Cc: Lee Jones <lee.jones@linaro.org>
>> Cc: Chanwoo Choi <cw00.choi@samsung.com>
>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Applied, thanks,
-Bryan

[PATCH v6 04/10] DT: Add documentation for the Skyworks AAT1290

[Jacek Anaszewski]

This patch adds device tree binding documentation for
1.5A Step-Up Current Regulator for Flash LEDs.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: devicetree@vger.kernel.org
---
 .../devicetree/bindings/leds/leds-aat1290.txt      |   41 ++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-aat1290.txt

diff --git a/Documentation/devicetree/bindings/leds/leds-aat1290.txt b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
new file mode 100644
index 0000000..ef88b9c
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
@@ -0,0 +1,41 @@
+* Skyworks Solutions, Inc. AAT1290 Current Regulator for Flash LEDs
+
+The device is controlled through two pins: FL_EN and EN_SET. The pins when,
+asserted high, enable flash strobe and movie mode (max 1/2 of flash current)
+respectively.
+
+Required properties:
+
+- compatible : Must be "skyworks,aat1290".
+- flen-gpios : Must be device tree identifier of the flash device FL_EN pin.
+- enset-gpios : Must be device tree identifier of the flash device EN_SET pin.
+
+A discrete LED element connected to the device must be represented by a child
+node - see Documentation/devicetree/bindings/leds/common.txt.
+
+Required properties of the LED child node:
+- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+                       Maximum flash LED supply current can be calculated using
+                       following formula: I = 1A * 162kohm / Rset.
+- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+                     Maximum flash timeout can be calculated using following
+                     formula: T = 8.82 * 10^9 * Ct.
+
+Optional properties of the LED child node:
+- label : see Documentation/devicetree/bindings/leds/common.txt
+
+Example (by Ct = 220nF, Rset = 160kohm):
+
+aat1290 {
+	compatible = "skyworks,aat1290";
+	flen-gpios = <&gpj1 1 GPIO_ACTIVE_HIGH>;
+	enset-gpios = <&gpj1 2 GPIO_ACTIVE_HIGH>;
+
+	camera_flash: flash-led {
+		label = "aat1290-flash";
+		led-max-microamp = <520833>;
+		flash-max-microamp = <1012500>;
+		flash-timeout-us = <1940000>;
+	};
+};
-- 
1.7.9.5

Re: [PATCH v6 04/10] DT: Add documentation for the Skyworks AAT1290

[Bryan Wu]

On Tue, Apr 28, 2015 at 12:18 AM, Jacek Anaszewski
<j.anaszewski@samsung.com> wrote:
> This patch adds device tree binding documentation for
> 1.5A Step-Up Current Regulator for Flash LEDs.
>

Applied, thanks,
-Bryan

> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: devicetree@vger.kernel.org
> ---
>  .../devicetree/bindings/leds/leds-aat1290.txt      |   41 ++++++++++++++++++++
>  1 file changed, 41 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/leds-aat1290.txt
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-aat1290.txt b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
> new file mode 100644
> index 0000000..ef88b9c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
> @@ -0,0 +1,41 @@
> +* Skyworks Solutions, Inc. AAT1290 Current Regulator for Flash LEDs
> +
> +The device is controlled through two pins: FL_EN and EN_SET. The pins when,
> +asserted high, enable flash strobe and movie mode (max 1/2 of flash current)
> +respectively.
> +
> +Required properties:
> +
> +- compatible : Must be "skyworks,aat1290".
> +- flen-gpios : Must be device tree identifier of the flash device FL_EN pin.
> +- enset-gpios : Must be device tree identifier of the flash device EN_SET pin.
> +
> +A discrete LED element connected to the device must be represented by a child
> +node - see Documentation/devicetree/bindings/leds/common.txt.
> +
> +Required properties of the LED child node:
> +- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +                       Maximum flash LED supply current can be calculated using
> +                       following formula: I = 1A * 162kohm / Rset.
> +- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
> +                     Maximum flash timeout can be calculated using following
> +                     formula: T = 8.82 * 10^9 * Ct.
> +
> +Optional properties of the LED child node:
> +- label : see Documentation/devicetree/bindings/leds/common.txt
> +
> +Example (by Ct = 220nF, Rset = 160kohm):
> +
> +aat1290 {
> +       compatible = "skyworks,aat1290";
> +       flen-gpios = <&gpj1 1 GPIO_ACTIVE_HIGH>;
> +       enset-gpios = <&gpj1 2 GPIO_ACTIVE_HIGH>;
> +
> +       camera_flash: flash-led {
> +               label = "aat1290-flash";
> +               led-max-microamp = <520833>;
> +               flash-max-microamp = <1012500>;
> +               flash-timeout-us = <1940000>;
> +       };
> +};
> --
> 1.7.9.5
>

[PATCH v6 05/10] leds: Add driver for AAT1290 flash LED controller

[Jacek Anaszewski]

This patch adds a driver for the 1.5A Step-Up Current Regulator
for Flash LEDs. The device is programmed through a Skyworks proprietary
AS2Cwire serial digital interface.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
 drivers/leds/Kconfig        |    8 +
 drivers/leds/Makefile       |    1 +
 drivers/leds/leds-aat1290.c |  452 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 461 insertions(+)
 create mode 100644 drivers/leds/leds-aat1290.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 62be033..dd7834c 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -42,6 +42,14 @@ config LEDS_88PM860X
 	  This option enables support for on-chip LED drivers found on Marvell
 	  Semiconductor 88PM8606 PMIC.
 
+config LEDS_AAT1290
+	tristate "LED support for the AAT1290"
+	depends on LEDS_CLASS_FLASH
+	depends on GPIOLIB
+	depends on OF
+	help
+	 This option enables support for the LEDs on the AAT1290.
+
 config LEDS_LM3530
 	tristate "LCD Backlight driver for LM3530"
 	depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 8bddae6..71f7c9a 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_LEDS_TRIGGERS)		+= led-triggers.o
 
 # LED Platform Drivers
 obj-$(CONFIG_LEDS_88PM860X)		+= leds-88pm860x.o
+obj-$(CONFIG_LEDS_AAT1290)		+= leds-aat1290.o
 obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
 obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
 obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
new file mode 100644
index 0000000..03e5b96
--- /dev/null
+++ b/drivers/leds/leds-aat1290.c
@@ -0,0 +1,452 @@
+/*
+ *	LED Flash class driver for the AAT1290
+ *	1.5A Step-Up Current Regulator for Flash LEDs
+ *
+ *	Copyright (C) 2015, Samsung Electronics Co., Ltd.
+ *	Author: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *
+ * 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/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/led-class-flash.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
+#define AAT1290_MAX_MM_CURR_PERCENT_0	16
+#define AAT1290_MAX_MM_CURR_PERCENT_100	1
+
+#define AAT1290_FLASH_SAFETY_TIMER_ADDR	18
+
+#define AAT1290_MOVIE_MODE_CONFIG_ADDR	19
+#define AAT1290_MOVIE_MODE_OFF		1
+#define AAT1290_MOVIE_MODE_ON		3
+
+#define AAT1290_MM_CURRENT_RATIO_ADDR	20
+#define AAT1290_MM_TO_FL_1_92		1
+
+#define AAT1290_MM_TO_FL_RATIO		1000 / 1920
+#define AAT1290_MAX_MM_CURRENT(fl_max)	(fl_max * AAT1290_MM_TO_FL_RATIO)
+
+#define AAT1290_LATCH_TIME_MIN_US	500
+#define AAT1290_LATCH_TIME_MAX_US	1000
+#define AAT1290_EN_SET_TICK_TIME_US	1
+#define AAT1290_FLEN_OFF_DELAY_TIME_US	10
+#define AAT1290_FLASH_TM_NUM_LEVELS	16
+#define AAT1290_MM_CURRENT_SCALE_SIZE	15
+
+
+struct aat1290_led_config_data {
+	/* maximum LED current in movie mode */
+	u32 max_mm_current;
+	/* maximum LED current in flash mode */
+	u32 max_flash_current;
+	/* maximum flash timeout */
+	u32 max_flash_tm;
+	/* max LED brightness level */
+	enum led_brightness max_brightness;
+};
+
+struct aat1290_led {
+	/* platform device data */
+	struct platform_device *pdev;
+	/* secures access to the device */
+	struct mutex lock;
+
+	/* corresponding LED Flash class device */
+	struct led_classdev_flash fled_cdev;
+
+	/* FLEN pin */
+	struct gpio_desc *gpio_fl_en;
+	/* EN|SET pin  */
+	struct gpio_desc *gpio_en_set;
+	/* movie mode current scale */
+	int *mm_current_scale;
+	/* device mode */
+	bool movie_mode;
+
+	/* brightness cache */
+	unsigned int torch_brightness;
+	/* assures led-triggers compatibility */
+	struct work_struct work_brightness_set;
+};
+
+static struct aat1290_led *fled_cdev_to_led(
+				struct led_classdev_flash *fled_cdev)
+{
+	return container_of(fled_cdev, struct aat1290_led, fled_cdev);
+}
+
+static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
+{
+	int i;
+
+	gpiod_direction_output(led->gpio_fl_en, 0);
+	gpiod_direction_output(led->gpio_en_set, 0);
+
+	udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);
+
+	/* write address */
+	for (i = 0; i < addr; ++i) {
+		udelay(AAT1290_EN_SET_TICK_TIME_US);
+		gpiod_direction_output(led->gpio_en_set, 0);
+		udelay(AAT1290_EN_SET_TICK_TIME_US);
+		gpiod_direction_output(led->gpio_en_set, 1);
+	}
+
+	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
+
+	/* write data */
+	for (i = 0; i < value; ++i) {
+		udelay(AAT1290_EN_SET_TICK_TIME_US);
+		gpiod_direction_output(led->gpio_en_set, 0);
+		udelay(AAT1290_EN_SET_TICK_TIME_US);
+		gpiod_direction_output(led->gpio_en_set, 1);
+	}
+
+	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
+}
+
+static void aat1290_set_flash_safety_timer(struct aat1290_led *led,
+					unsigned int micro_sec)
+{
+	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
+	struct led_flash_setting *flash_tm = &fled_cdev->timeout;
+	int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -
+				(micro_sec / flash_tm->step) + 1;
+
+	aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,
+							flash_tm_reg);
+}
+
+static void aat1290_brightness_set(struct aat1290_led *led,
+					enum led_brightness brightness)
+{
+	mutex_lock(&led->lock);
+
+	if (brightness == 0) {
+		gpiod_direction_output(led->gpio_fl_en, 0);
+		gpiod_direction_output(led->gpio_en_set, 0);
+		led->movie_mode = false;
+	} else {
+		if (!led->movie_mode) {
+			aat1290_as2cwire_write(led,
+				AAT1290_MM_CURRENT_RATIO_ADDR,
+				AAT1290_MM_TO_FL_1_92);
+			led->movie_mode = true;
+		}
+
+		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
+				AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
+		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
+				AAT1290_MOVIE_MODE_ON);
+	}
+
+	mutex_unlock(&led->lock);
+}
+
+/* LED subsystem callbacks */
+
+static void aat1290_brightness_set_work(struct work_struct *work)
+{
+	struct aat1290_led *led =
+		container_of(work, struct aat1290_led, work_brightness_set);
+
+	aat1290_brightness_set(led, led->torch_brightness);
+}
+
+static void aat1290_led_brightness_set(struct led_classdev *led_cdev,
+					enum led_brightness brightness)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
+
+	led->torch_brightness = brightness;
+	schedule_work(&led->work_brightness_set);
+}
+
+static int aat1290_led_brightness_set_sync(struct led_classdev *led_cdev,
+					enum led_brightness brightness)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
+
+	aat1290_brightness_set(led, brightness);
+
+	return 0;
+}
+
+static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
+					 bool state)
+
+{
+	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct led_flash_setting *timeout = &fled_cdev->timeout;
+
+	mutex_lock(&led->lock);
+
+	if (state == 0) {
+		gpiod_direction_output(led->gpio_fl_en, 0);
+		gpiod_direction_output(led->gpio_en_set, 0);
+	} else {
+		aat1290_set_flash_safety_timer(led, timeout->val);
+		gpiod_direction_output(led->gpio_fl_en, 1);
+	}
+
+	/*
+	 * To reenter movie mode after a flash event the part must be cycled
+	 * off and back on to reset the movie mode and reprogrammed via the
+	 * AS2Cwire. Therefore the brightness and movie_mode properties needs
+	 * to be updated here to reflect the actual state.
+	 */
+	led_cdev->brightness = 0;
+	led->movie_mode = false;
+
+	mutex_unlock(&led->lock);
+
+	return 0;
+}
+
+static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
+						u32 timeout)
+{
+	/*
+	 * Don't do anything - flash timeout is cached in the led-class-flash
+	 * core and will be applied in the strobe_set op, as writing the
+	 * safety timer register spuriously turns the torch mode on.
+	 */
+
+	return 0;
+}
+
+static int aat1290_led_parse_dt(struct aat1290_led *led,
+			struct aat1290_led_config_data *cfg)
+{
+	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
+	struct device *dev = &led->pdev->dev;
+	struct device_node *child_node;
+	int ret = 0;
+
+	led->gpio_fl_en = devm_gpiod_get(dev, "flen");
+	if (IS_ERR(led->gpio_fl_en)) {
+		ret = PTR_ERR(led->gpio_fl_en);
+		dev_err(dev, "Unable to claim gpio \"flen\".\n");
+		return ret;
+	}
+
+	led->gpio_en_set = devm_gpiod_get(dev, "enset");
+	if (IS_ERR(led->gpio_en_set)) {
+		ret = PTR_ERR(led->gpio_en_set);
+		dev_err(dev, "Unable to claim gpio \"enset\".\n");
+		return ret;
+	}
+
+	child_node = of_get_next_available_child(dev->of_node, NULL);
+	if (!child_node) {
+		dev_err(dev, "No DT child node found for connected LED.\n");
+		return -EINVAL;
+	}
+
+	led_cdev->name = of_get_property(child_node, "label", NULL) ? :
+						child_node->name;
+
+	ret = of_property_read_u32(child_node, "led-max-microamp",
+				&cfg->max_mm_current);
+	/*
+	 * led-max-microamp will default to 1/20 of flash-max-microamp
+	 * in case it is missing.
+	 */
+	if (ret < 0)
+		dev_warn(dev,
+			"led-max-microamp DT property missing\n");
+
+	ret = of_property_read_u32(child_node, "flash-max-microamp",
+				&cfg->max_flash_current);
+	if (ret < 0) {
+		dev_err(dev,
+			"flash-max-microamp DT property missing\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(child_node, "flash-max-timeout-us",
+				&cfg->max_flash_tm);
+	if (ret < 0) {
+		dev_err(dev,
+			"flash-max-timeout-us DT property missing\n");
+		return ret;
+	}
+
+	of_node_put(child_node);
+
+	return ret;
+}
+
+static void aat1290_led_validate_mm_current(struct aat1290_led *led,
+					struct aat1290_led_config_data *cfg)
+{
+	int i, b = 0, e = AAT1290_MM_CURRENT_SCALE_SIZE;
+
+	while (e - b > 1) {
+		i = b + (e - b) / 2;
+		if (cfg->max_mm_current < led->mm_current_scale[i])
+			e = i;
+		else
+			b = i;
+	}
+
+	cfg->max_mm_current = led->mm_current_scale[b];
+	cfg->max_brightness = b + 1;
+}
+
+int init_mm_current_scale(struct aat1290_led *led,
+			struct aat1290_led_config_data *cfg)
+{
+	int max_mm_current_percent[] = { 20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
+						63, 71, 79, 89, 100 };
+	int i, max_mm_current =
+			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
+
+	led->mm_current_scale = kzalloc(sizeof(max_mm_current_percent),
+					GFP_KERNEL);
+	if (!led->mm_current_scale)
+		return -ENOMEM;
+
+	for (i = 0; i < AAT1290_MM_CURRENT_SCALE_SIZE; ++i)
+		led->mm_current_scale[i] = max_mm_current *
+					  max_mm_current_percent[i] / 100;
+
+	return 0;
+}
+
+static int aat1290_led_get_configuration(struct aat1290_led *led,
+					struct aat1290_led_config_data *cfg)
+{
+	int ret;
+
+	ret = aat1290_led_parse_dt(led, cfg);
+	if (ret < 0)
+		return ret;
+	/*
+	 * Init non-linear movie mode current scale basing
+	 * on the max flash current from led configuration.
+	 */
+	ret = init_mm_current_scale(led, cfg);
+	if (ret < 0)
+		return ret;
+
+	aat1290_led_validate_mm_current(led, cfg);
+
+	kfree(led->mm_current_scale);
+
+	return 0;
+}
+
+static void aat1290_init_flash_timeout(struct aat1290_led *led,
+				struct aat1290_led_config_data *cfg)
+{
+	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
+	struct led_flash_setting *setting;
+
+	/* Init flash timeout setting */
+	setting = &fled_cdev->timeout;
+	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
+	setting->max = cfg->max_flash_tm;
+	setting->step = setting->min;
+	setting->val = setting->max;
+}
+
+static const struct led_flash_ops flash_ops = {
+	.strobe_set = aat1290_led_flash_strobe_set,
+	.timeout_set = aat1290_led_flash_timeout_set,
+};
+
+static int aat1290_led_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct aat1290_led *led;
+	struct led_classdev *led_cdev;
+	struct led_classdev_flash *fled_cdev;
+	struct aat1290_led_config_data led_cfg = {};
+	int ret;
+
+	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
+	if (!led)
+		return -ENOMEM;
+
+	led->pdev = pdev;
+	platform_set_drvdata(pdev, led);
+
+	fled_cdev = &led->fled_cdev;
+	fled_cdev->ops = &flash_ops;
+	led_cdev = &fled_cdev->led_cdev;
+
+	ret = aat1290_led_get_configuration(led, &led_cfg);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&led->lock);
+
+	/* Initialize LED Flash class device */
+	led_cdev->brightness_set = aat1290_led_brightness_set;
+	led_cdev->brightness_set_sync = aat1290_led_brightness_set_sync;
+	led_cdev->max_brightness = led_cfg.max_brightness;
+	led_cdev->flags |= LED_DEV_CAP_FLASH;
+	INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work);
+
+	aat1290_init_flash_timeout(led, &led_cfg);
+
+	/* Register LED Flash class device */
+	ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
+	if (ret < 0)
+		goto err_flash_register;
+
+	return 0;
+
+err_flash_register:
+	mutex_destroy(&led->lock);
+
+	return ret;
+}
+
+static int aat1290_led_remove(struct platform_device *pdev)
+{
+	struct aat1290_led *led = platform_get_drvdata(pdev);
+
+	led_classdev_flash_unregister(&led->fled_cdev);
+	cancel_work_sync(&led->work_brightness_set);
+
+	mutex_destroy(&led->lock);
+
+	return 0;
+}
+
+static const struct of_device_id aat1290_led_dt_match[] = {
+	{ .compatible = "skyworks,aat1290" },
+	{},
+};
+
+static struct platform_driver aat1290_led_driver = {
+	.probe		= aat1290_led_probe,
+	.remove		= aat1290_led_remove,
+	.driver		= {
+		.name	= "aat1290",
+		.owner	= THIS_MODULE,
+		.of_match_table = aat1290_led_dt_match,
+	},
+};
+
+module_platform_driver(aat1290_led_driver);
+
+MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
+MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5

Re: [PATCH v6 05/10] leds: Add driver for AAT1290 flash LED controller

[Sakari Ailus]

On Tue, Apr 28, 2015 at 09:18:45AM +0200, Jacek Anaszewski wrote:
> This patch adds a driver for the 1.5A Step-Up Current Regulator
> for Flash LEDs. The device is programmed through a Skyworks proprietary
> AS2Cwire serial digital interface.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

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

Re: [PATCH v6 05/10] leds: Add driver for AAT1290 flash LED controller

[Bryan Wu]

On Tue, Apr 28, 2015 at 4:36 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote:
> On Tue, Apr 28, 2015 at 09:18:45AM +0200, Jacek Anaszewski wrote:
>> This patch adds a driver for the 1.5A Step-Up Current Regulator
>> for Flash LEDs. The device is programmed through a Skyworks proprietary
>> AS2Cwire serial digital interface.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>
Applied, thanks,
-Bryan

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

Re: [PATCH v6 05/10] leds: Add driver for AAT1290 flash LED controller

[Pavel Machek]

> +struct aat1290_led_config_data {
> +	/* maximum LED current in movie mode */
> +	u32 max_mm_current;
> +	/* maximum LED current in flash mode */
> +	u32 max_flash_current;
> +	/* maximum flash timeout */
> +	u32 max_flash_tm;

Ok, the comments tell us what should be already obvious from the
variable names... but it would be nice to add units. (mA? uA? msec?)
(I guess in subsequent patch).
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[PATCH v6 06/10] media: Add registration helpers for V4L2 flash sub-devices

[Jacek Anaszewski]

This patch adds helper functions for registering/unregistering
LED Flash class devices as V4L2 sub-devices. The functions should
be called from the LED subsystem device driver. In case the
support for V4L2 Flash sub-devices is disabled in the kernel
config the functions' empty versions will be used.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/v4l2-core/Kconfig                |   11 +
 drivers/media/v4l2-core/Makefile               |    2 +
 drivers/media/v4l2-core/v4l2-flash-led-class.c |  626 ++++++++++++++++++++++++
 include/media/v4l2-flash-led-class.h           |  145 ++++++
 4 files changed, 784 insertions(+)
 create mode 100644 drivers/media/v4l2-core/v4l2-flash-led-class.c
 create mode 100644 include/media/v4l2-flash-led-class.h

diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index ba7e21a..c505dc3 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -44,6 +44,17 @@ config V4L2_MEM2MEM_DEV
         tristate
         depends on VIDEOBUF2_CORE
 
+# Used by LED subsystem flash drivers
+config V4L2_FLASH_LED_CLASS
+	tristate "V4L2 flash API for LED flash class devices"
+	depends on VIDEO_V4L2_SUBDEV_API
+	depends on LEDS_CLASS_FLASH
+	---help---
+	  Say Y here to enable V4L2 flash API support for LED flash
+	  class drivers.
+
+	  When in doubt, say N.
+
 # Used by drivers that need Videobuf modules
 config VIDEOBUF_GEN
 	tristate
diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile
index 63d29f2..dc3de00 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -22,6 +22,8 @@ obj-$(CONFIG_VIDEO_TUNER) += tuner.o
 
 obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o
 
+obj-$(CONFIG_V4L2_FLASH_LED_CLASS) += v4l2-flash-led-class.o
+
 obj-$(CONFIG_VIDEOBUF_GEN) += videobuf-core.o
 obj-$(CONFIG_VIDEOBUF_DMA_SG) += videobuf-dma-sg.o
 obj-$(CONFIG_VIDEOBUF_DMA_CONTIG) += videobuf-dma-contig.o
diff --git a/drivers/media/v4l2-core/v4l2-flash-led-class.c b/drivers/media/v4l2-core/v4l2-flash-led-class.c
new file mode 100644
index 0000000..4075507
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-flash-led-class.c
@@ -0,0 +1,626 @@
+/*
+ * V4L2 flash LED sub-device registration helpers.
+ *
+ *	Copyright (C) 2015 Samsung Electronics Co., Ltd
+ *	Author: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *
+ * 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/led-class-flash.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <media/v4l2-flash-led-class.h>
+
+#define has_flash_op(v4l2_flash, op)				\
+	(v4l2_flash && v4l2_flash->ops->op)
+
+#define call_flash_op(v4l2_flash, op, arg)			\
+		(has_flash_op(v4l2_flash, op) ?			\
+			v4l2_flash->ops->op(v4l2_flash, arg) :	\
+			-EINVAL)
+
+static enum led_brightness __intensity_to_led_brightness(
+					struct v4l2_ctrl *ctrl, s32 intensity)
+{
+	intensity -= ctrl->minimum;
+	intensity /= (u32) ctrl->step;
+
+	/*
+	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
+	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
+	 * Therefore it must be possible to set it to 0 level which in
+	 * the LED subsystem reflects LED_OFF state.
+	 */
+	if (ctrl->minimum)
+		++intensity;
+
+	return intensity;
+}
+
+static s32 __led_brightness_to_intensity(struct v4l2_ctrl *ctrl,
+					 enum led_brightness brightness)
+{
+	/*
+	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
+	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
+	 * Do not decrement brightness read from the LED subsystem for
+	 * indicator LED as it may equal 0. For torch LEDs this function
+	 * is called only when V4L2_FLASH_LED_MODE_TORCH is set and the
+	 * brightness read is guaranteed to be greater than 0. In the mode
+	 * V4L2_FLASH_LED_MODE_NONE the cached torch intensity value is used.
+	 */
+	if (ctrl->id != V4L2_CID_FLASH_INDICATOR_INTENSITY)
+		--brightness;
+
+	return (brightness * ctrl->step) + ctrl->minimum;
+}
+
+static void v4l2_flash_set_led_brightness(struct v4l2_flash *v4l2_flash,
+					struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
+	enum led_brightness brightness;
+
+	if (has_flash_op(v4l2_flash, intensity_to_led_brightness))
+		brightness = call_flash_op(v4l2_flash,
+					intensity_to_led_brightness,
+					ctrl->val);
+	else
+		brightness = __intensity_to_led_brightness(ctrl, ctrl->val);
+	/*
+	 * In case a LED Flash class driver provides ops for custom
+	 * brightness <-> intensity conversion, it also must have defined
+	 * related v4l2 control step == 1. In such a case a backward conversion
+	 * from led brightness to v4l2 intensity is required to find out the
+	 * the aligned intensity value.
+	 */
+	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
+		ctrl->val = call_flash_op(v4l2_flash,
+					led_brightness_to_intensity,
+					brightness);
+
+	if (ctrl == ctrls[TORCH_INTENSITY] &&
+	    ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
+		return;
+
+	led_set_brightness(&v4l2_flash->fled_cdev->led_cdev, brightness);
+}
+
+static int v4l2_flash_update_led_brightness(struct v4l2_flash *v4l2_flash,
+					struct v4l2_ctrl *ctrl)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
+	int ret;
+
+	/*
+	 * Update torch brightness only if in TORCH_MODE. In other modes torch
+	 * led is turned off, which would spuriously inform the user space that
+	 * V4L2_CID_FLASH_TORCH_INTENSITY control value has changed to 0.
+	 */
+	if (ctrl == ctrls[TORCH_INTENSITY] &&
+	    ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
+		return 0;
+
+	ret = led_update_brightness(led_cdev);
+	if (ret < 0)
+		return ret;
+
+	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
+		ctrl->val = call_flash_op(v4l2_flash,
+						led_brightness_to_intensity,
+						led_cdev->brightness);
+	else
+		ctrl->val = __led_brightness_to_intensity(ctrl,
+						led_cdev->brightness);
+
+	return 0;
+}
+
+static int v4l2_flash_g_volatile_ctrl(struct v4l2_ctrl *c)
+{
+	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	bool is_strobing;
+	int ret;
+
+	switch (c->id) {
+	case V4L2_CID_FLASH_TORCH_INTENSITY:
+	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
+		return v4l2_flash_update_led_brightness(v4l2_flash, c);
+	case V4L2_CID_FLASH_INTENSITY:
+		ret = led_update_flash_brightness(fled_cdev);
+		if (ret < 0)
+			return ret;
+		/*
+		 * No conversion is needed as LED Flash class also uses
+		 * microamperes for flash intensity units.
+		 */
+		c->val = fled_cdev->brightness.val;
+		return 0;
+	case V4L2_CID_FLASH_STROBE_STATUS:
+		ret = led_get_flash_strobe(fled_cdev, &is_strobing);
+		if (ret < 0)
+			return ret;
+		c->val = is_strobing;
+		return 0;
+	case V4L2_CID_FLASH_FAULT:
+		/* LED faults map directly to V4L2 flash faults */
+		return led_get_flash_fault(fled_cdev, &c->val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static bool __software_strobe_mode_inactive(struct v4l2_ctrl **ctrls)
+{
+	return ((ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH) ||
+		(ctrls[STROBE_SOURCE] && (ctrls[STROBE_SOURCE]->val !=
+				V4L2_FLASH_STROBE_SOURCE_SOFTWARE)));
+}
+
+static int v4l2_flash_s_ctrl(struct v4l2_ctrl *c)
+{
+	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
+	bool external_strobe;
+	int ret = 0;
+
+	switch (c->id) {
+	case V4L2_CID_FLASH_LED_MODE:
+		switch (c->val) {
+		case V4L2_FLASH_LED_MODE_NONE:
+			led_set_brightness(led_cdev, LED_OFF);
+			return led_set_flash_strobe(fled_cdev, false);
+		case V4L2_FLASH_LED_MODE_FLASH:
+			/* Turn the torch LED off */
+			led_set_brightness(led_cdev, LED_OFF);
+			if (ctrls[STROBE_SOURCE]) {
+				external_strobe = (ctrls[STROBE_SOURCE]->val ==
+					V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
+
+				ret = call_flash_op(v4l2_flash,
+						external_strobe_set,
+						external_strobe);
+			}
+			return ret;
+		case V4L2_FLASH_LED_MODE_TORCH:
+			if (ctrls[STROBE_SOURCE]) {
+				ret = call_flash_op(v4l2_flash,
+						external_strobe_set,
+						false);
+				if (ret < 0)
+					return ret;
+			}
+			/* Stop flash strobing */
+			ret = led_set_flash_strobe(fled_cdev, false);
+			if (ret < 0)
+				return ret;
+
+			v4l2_flash_set_led_brightness(v4l2_flash,
+							ctrls[TORCH_INTENSITY]);
+			return 0;
+		}
+		break;
+	case V4L2_CID_FLASH_STROBE_SOURCE:
+		external_strobe = (c->val == V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
+		/*
+		 * For some hardware arrangements setting strobe source may
+		 * affect torch mode. Therefore, if not in the flash mode,
+		 * cache only this setting. It will be applied upon switching
+		 * to flash mode.
+		 */
+		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH)
+			return 0;
+
+		return call_flash_op(v4l2_flash, external_strobe_set,
+					external_strobe);
+	case V4L2_CID_FLASH_STROBE:
+		if (__software_strobe_mode_inactive(ctrls))
+			return -EBUSY;
+		return led_set_flash_strobe(fled_cdev, true);
+	case V4L2_CID_FLASH_STROBE_STOP:
+		if (__software_strobe_mode_inactive(ctrls))
+			return -EBUSY;
+		return led_set_flash_strobe(fled_cdev, false);
+	case V4L2_CID_FLASH_TIMEOUT:
+		/*
+		 * No conversion is needed as LED Flash class also uses
+		 * microseconds for flash timeout units.
+		 */
+		return led_set_flash_timeout(fled_cdev, c->val);
+	case V4L2_CID_FLASH_INTENSITY:
+		/*
+		 * No conversion is needed as LED Flash class also uses
+		 * microamperes for flash intensity units.
+		 */
+		return led_set_flash_brightness(fled_cdev, c->val);
+	case V4L2_CID_FLASH_TORCH_INTENSITY:
+	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
+		v4l2_flash_set_led_brightness(v4l2_flash, c);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static const struct v4l2_ctrl_ops v4l2_flash_ctrl_ops = {
+	.g_volatile_ctrl = v4l2_flash_g_volatile_ctrl,
+	.s_ctrl = v4l2_flash_s_ctrl,
+};
+
+static void __lfs_to_v4l2_ctrl_config(struct led_flash_setting *s,
+				struct v4l2_ctrl_config *c)
+{
+	c->min = s->min;
+	c->max = s->max;
+	c->step = s->step;
+	c->def = s->val;
+}
+
+static void __fill_ctrl_init_data(struct v4l2_flash *v4l2_flash,
+			  struct v4l2_flash_config *flash_cfg,
+			  struct v4l2_flash_ctrl_data *ctrl_init_data)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	const struct led_flash_ops *fled_cdev_ops = fled_cdev->ops;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct v4l2_ctrl_config *ctrl_cfg;
+	u32 mask;
+
+	/* Init FLASH_FAULT ctrl data */
+	if (flash_cfg->flash_faults) {
+		ctrl_init_data[FLASH_FAULT].cid = V4L2_CID_FLASH_FAULT;
+		ctrl_cfg = &ctrl_init_data[FLASH_FAULT].config;
+		ctrl_cfg->id = V4L2_CID_FLASH_FAULT;
+		ctrl_cfg->max = flash_cfg->flash_faults;
+		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
+				  V4L2_CTRL_FLAG_READ_ONLY;
+	}
+
+	/* Init INDICATOR_INTENSITY ctrl data */
+	if (flash_cfg->indicator_led) {
+		ctrl_init_data[INDICATOR_INTENSITY].cid =
+					V4L2_CID_FLASH_INDICATOR_INTENSITY;
+		ctrl_cfg = &ctrl_init_data[INDICATOR_INTENSITY].config;
+		__lfs_to_v4l2_ctrl_config(&flash_cfg->intensity, ctrl_cfg);
+		ctrl_cfg->id = V4L2_CID_FLASH_INDICATOR_INTENSITY;
+		ctrl_cfg->min = 0;
+		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE;
+
+		/* Indicator LED can have only faults and intensity controls. */
+		return;
+	}
+
+	/* Init FLASH_LED_MODE ctrl data */
+	mask = 1 << V4L2_FLASH_LED_MODE_NONE |
+	       1 << V4L2_FLASH_LED_MODE_TORCH;
+	if (led_cdev->flags & LED_DEV_CAP_FLASH)
+		mask |= 1 << V4L2_FLASH_LED_MODE_FLASH;
+
+	ctrl_init_data[LED_MODE].cid = V4L2_CID_FLASH_LED_MODE;
+	ctrl_cfg = &ctrl_init_data[LED_MODE].config;
+	ctrl_cfg->id = V4L2_CID_FLASH_LED_MODE;
+	ctrl_cfg->max = V4L2_FLASH_LED_MODE_TORCH;
+	ctrl_cfg->menu_skip_mask = ~mask;
+	ctrl_cfg->def = V4L2_FLASH_LED_MODE_NONE;
+	ctrl_cfg->flags = 0;
+
+	/* Init TORCH_INTENSITY ctrl data */
+	ctrl_init_data[TORCH_INTENSITY].cid = V4L2_CID_FLASH_TORCH_INTENSITY;
+	ctrl_cfg = &ctrl_init_data[TORCH_INTENSITY].config;
+	__lfs_to_v4l2_ctrl_config(&flash_cfg->intensity, ctrl_cfg);
+	ctrl_cfg->id = V4L2_CID_FLASH_TORCH_INTENSITY;
+	ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE;
+
+	if (!(led_cdev->flags & LED_DEV_CAP_FLASH))
+		return;
+
+	/* Init FLASH_STROBE ctrl data */
+	ctrl_init_data[FLASH_STROBE].cid = V4L2_CID_FLASH_STROBE;
+	ctrl_cfg = &ctrl_init_data[FLASH_STROBE].config;
+	ctrl_cfg->id = V4L2_CID_FLASH_STROBE;
+
+	/* Init STROBE_STOP ctrl data */
+	ctrl_init_data[STROBE_STOP].cid = V4L2_CID_FLASH_STROBE_STOP;
+	ctrl_cfg = &ctrl_init_data[STROBE_STOP].config;
+	ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STOP;
+
+	/* Init FLASH_STROBE_SOURCE ctrl data */
+	if (flash_cfg->has_external_strobe) {
+		mask = (1 << V4L2_FLASH_STROBE_SOURCE_SOFTWARE) |
+		       (1 << V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
+		ctrl_init_data[STROBE_SOURCE].cid =
+					V4L2_CID_FLASH_STROBE_SOURCE;
+		ctrl_cfg = &ctrl_init_data[STROBE_SOURCE].config;
+		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_SOURCE;
+		ctrl_cfg->max = V4L2_FLASH_STROBE_SOURCE_EXTERNAL;
+		ctrl_cfg->menu_skip_mask = ~mask;
+		ctrl_cfg->def = V4L2_FLASH_STROBE_SOURCE_SOFTWARE;
+	}
+
+	/* Init STROBE_STATUS ctrl data */
+	if (fled_cdev_ops->strobe_get) {
+		ctrl_init_data[STROBE_STATUS].cid =
+					V4L2_CID_FLASH_STROBE_STATUS;
+		ctrl_cfg = &ctrl_init_data[STROBE_STATUS].config;
+		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STATUS;
+		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
+				  V4L2_CTRL_FLAG_READ_ONLY;
+	}
+
+	/* Init FLASH_TIMEOUT ctrl data */
+	if (fled_cdev_ops->timeout_set) {
+		ctrl_init_data[FLASH_TIMEOUT].cid = V4L2_CID_FLASH_TIMEOUT;
+		ctrl_cfg = &ctrl_init_data[FLASH_TIMEOUT].config;
+		__lfs_to_v4l2_ctrl_config(&fled_cdev->timeout, ctrl_cfg);
+		ctrl_cfg->id = V4L2_CID_FLASH_TIMEOUT;
+	}
+
+	/* Init FLASH_INTENSITY ctrl data */
+	if (fled_cdev_ops->flash_brightness_set) {
+		ctrl_init_data[FLASH_INTENSITY].cid = V4L2_CID_FLASH_INTENSITY;
+		ctrl_cfg = &ctrl_init_data[FLASH_INTENSITY].config;
+		__lfs_to_v4l2_ctrl_config(&fled_cdev->brightness, ctrl_cfg);
+		ctrl_cfg->id = V4L2_CID_FLASH_INTENSITY;
+		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE;
+	}
+}
+
+static int v4l2_flash_init_controls(struct v4l2_flash *v4l2_flash,
+				struct v4l2_flash_config *flash_cfg)
+
+{
+	struct v4l2_flash_ctrl_data *ctrl_init_data;
+	struct v4l2_ctrl *ctrl;
+	struct v4l2_ctrl_config *ctrl_cfg;
+	int i, ret, num_ctrls = 0;
+
+	/* allocate memory dynamically so as not to exceed stack frame size */
+	ctrl_init_data = kcalloc(NUM_FLASH_CTRLS, sizeof(*ctrl_init_data),
+					GFP_KERNEL);
+	if (!ctrl_init_data)
+		return -ENOMEM;
+
+	__fill_ctrl_init_data(v4l2_flash, flash_cfg, ctrl_init_data);
+
+	for (i = 0; i < NUM_FLASH_CTRLS; ++i)
+		if (ctrl_init_data[i].cid)
+			++num_ctrls;
+
+	v4l2_ctrl_handler_init(&v4l2_flash->hdl, num_ctrls);
+
+	for (i = 0; i < NUM_FLASH_CTRLS; ++i) {
+		ctrl_cfg = &ctrl_init_data[i].config;
+		if (!ctrl_init_data[i].cid)
+			continue;
+
+		if (ctrl_cfg->id == V4L2_CID_FLASH_LED_MODE ||
+		    ctrl_cfg->id == V4L2_CID_FLASH_STROBE_SOURCE)
+			ctrl = v4l2_ctrl_new_std_menu(&v4l2_flash->hdl,
+						&v4l2_flash_ctrl_ops,
+						ctrl_cfg->id,
+						ctrl_cfg->max,
+						ctrl_cfg->menu_skip_mask,
+						ctrl_cfg->def);
+		else
+			ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl,
+						&v4l2_flash_ctrl_ops,
+						ctrl_cfg->id,
+						ctrl_cfg->min,
+						ctrl_cfg->max,
+						ctrl_cfg->step,
+						ctrl_cfg->def);
+
+		if (ctrl)
+			ctrl->flags |= ctrl_cfg->flags;
+
+		if (i <= STROBE_SOURCE)
+			v4l2_flash->ctrls[i] = ctrl;
+	}
+
+	kfree(ctrl_init_data);
+
+	if (v4l2_flash->hdl.error) {
+		ret = v4l2_flash->hdl.error;
+		goto error_free_handler;
+	}
+
+	v4l2_ctrl_handler_setup(&v4l2_flash->hdl);
+
+	v4l2_flash->sd.ctrl_handler = &v4l2_flash->hdl;
+
+	return 0;
+
+error_free_handler:
+	v4l2_ctrl_handler_free(&v4l2_flash->hdl);
+	return ret;
+}
+
+static int __sync_device_with_v4l2_controls(struct v4l2_flash *v4l2_flash)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
+	int ret = 0;
+
+	if (ctrls[INDICATOR_INTENSITY]) {
+		v4l2_flash_set_led_brightness(v4l2_flash,
+						ctrls[INDICATOR_INTENSITY]);
+		return 0;
+	}
+
+	v4l2_flash_set_led_brightness(v4l2_flash, ctrls[TORCH_INTENSITY]);
+
+	if (ctrls[FLASH_TIMEOUT]) {
+		ret = led_set_flash_timeout(fled_cdev,
+					ctrls[FLASH_TIMEOUT]->val);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (ctrls[FLASH_INTENSITY]) {
+		ret = led_set_flash_brightness(fled_cdev,
+					ctrls[FLASH_INTENSITY]->val);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * For some hardware arrangements setting strobe source may affect
+	 * torch mode. Synchronize strobe source setting only if not in torch
+	 * mode. For torch mode case it will get synchronized upon switching
+	 * to flash mode.
+	 */
+	if (ctrls[STROBE_SOURCE] &&
+	    ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
+		ret = call_flash_op(v4l2_flash, external_strobe_set,
+					ctrls[STROBE_SOURCE]->val);
+
+	return ret;
+}
+
+/*
+ * V4L2 subdev internal operations
+ */
+
+static int v4l2_flash_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	int ret = 0;
+
+	mutex_lock(&led_cdev->led_access);
+
+	if (!v4l2_fh_is_singular(&fh->vfh))
+		goto unlock;
+
+	led_sysfs_disable(led_cdev);
+	led_trigger_remove(led_cdev);
+
+	ret = __sync_device_with_v4l2_controls(v4l2_flash);
+
+unlock:
+	mutex_unlock(&led_cdev->led_access);
+	return ret;
+}
+
+static int v4l2_flash_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	int ret = 0;
+
+	mutex_lock(&led_cdev->led_access);
+
+	if (v4l2_fh_is_singular(&fh->vfh)) {
+		if (v4l2_flash->ctrls[STROBE_SOURCE])
+			ret = v4l2_ctrl_s_ctrl(v4l2_flash->ctrls[STROBE_SOURCE],
+					V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
+		led_sysfs_enable(led_cdev);
+	}
+
+	mutex_unlock(&led_cdev->led_access);
+
+	return ret;
+}
+
+static const struct v4l2_subdev_internal_ops v4l2_flash_subdev_internal_ops = {
+	.open = v4l2_flash_open,
+	.close = v4l2_flash_close,
+};
+
+static const struct v4l2_subdev_core_ops v4l2_flash_core_ops = {
+	.queryctrl = v4l2_subdev_queryctrl,
+	.querymenu = v4l2_subdev_querymenu,
+};
+
+static const struct v4l2_subdev_ops v4l2_flash_subdev_ops = {
+	.core = &v4l2_flash_core_ops,
+};
+
+struct v4l2_flash *v4l2_flash_init(struct led_classdev_flash *fled_cdev,
+				   const struct v4l2_flash_ops *ops,
+				   struct v4l2_flash_config *config)
+{
+	struct v4l2_flash *v4l2_flash;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct v4l2_subdev *sd;
+	int ret;
+
+	if (!fled_cdev || !ops || !config)
+		return ERR_PTR(-EINVAL);
+
+	v4l2_flash = devm_kzalloc(led_cdev->dev, sizeof(*v4l2_flash),
+					GFP_KERNEL);
+	if (!v4l2_flash)
+		return ERR_PTR(-ENOMEM);
+
+	sd = &v4l2_flash->sd;
+	v4l2_flash->fled_cdev = fled_cdev;
+	v4l2_flash->ops = ops;
+	sd->dev = led_cdev->dev;
+	v4l2_subdev_init(sd, &v4l2_flash_subdev_ops);
+	sd->internal_ops = &v4l2_flash_subdev_internal_ops;
+	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	strlcpy(sd->name, config->dev_name, sizeof(sd->name));
+
+	ret = media_entity_init(&sd->entity, 0, NULL, 0);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
+
+	ret = v4l2_flash_init_controls(v4l2_flash, config);
+	if (ret < 0)
+		goto err_init_controls;
+
+	of_node_get(led_cdev->dev->of_node);
+
+	ret = v4l2_async_register_subdev(sd);
+	if (ret < 0)
+		goto err_async_register_sd;
+
+	return v4l2_flash;
+
+err_async_register_sd:
+	of_node_put(led_cdev->dev->of_node);
+	v4l2_ctrl_handler_free(sd->ctrl_handler);
+err_init_controls:
+	media_entity_cleanup(&sd->entity);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(v4l2_flash_init);
+
+void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
+{
+	struct v4l2_subdev *sd;
+	struct led_classdev *led_cdev;
+
+	if (IS_ERR(v4l2_flash))
+		return;
+
+	sd = &v4l2_flash->sd;
+	led_cdev = &v4l2_flash->fled_cdev->led_cdev;
+
+	v4l2_async_unregister_subdev(sd);
+	of_node_put(led_cdev->dev->of_node);
+	v4l2_ctrl_handler_free(sd->ctrl_handler);
+	media_entity_cleanup(&sd->entity);
+}
+EXPORT_SYMBOL_GPL(v4l2_flash_release);
+
+MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
+MODULE_DESCRIPTION("V4L2 Flash sub-device helpers");
+MODULE_LICENSE("GPL v2");
diff --git a/include/media/v4l2-flash-led-class.h b/include/media/v4l2-flash-led-class.h
new file mode 100644
index 0000000..2796ccf
--- /dev/null
+++ b/include/media/v4l2-flash-led-class.h
@@ -0,0 +1,145 @@
+/*
+ * V4L2 flash LED sub-device registration helpers.
+ *
+ *	Copyright (C) 2015 Samsung Electronics Co., Ltd
+ *	Author: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *
+ * 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.
+ */
+
+#ifndef _V4L2_FLASH_H
+#define _V4L2_FLASH_H
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-subdev.h>
+
+struct led_classdev_flash;
+struct led_classdev;
+struct v4l2_flash;
+enum led_brightness;
+
+enum ctrl_init_data_id {
+	LED_MODE,
+	TORCH_INTENSITY,
+	FLASH_INTENSITY,
+	INDICATOR_INTENSITY,
+	FLASH_TIMEOUT,
+	STROBE_SOURCE,
+	/*
+	 * Only above values are applicable to
+	 * the 'ctrls' array in the struct v4l2_flash.
+	 */
+	FLASH_STROBE,
+	STROBE_STOP,
+	STROBE_STATUS,
+	FLASH_FAULT,
+	NUM_FLASH_CTRLS,
+};
+
+/*
+ * struct v4l2_flash_ctrl_data - flash control initialization data, filled
+ *				basing on the features declared by the LED Flash
+ *				class driver in the v4l2_flash_config
+ * @config:	initialization data for a control
+ * @cid:	contains v4l2 flash control id if the config
+ *		field was initialized, 0 otherwise
+ */
+struct v4l2_flash_ctrl_data {
+	struct v4l2_ctrl_config config;
+	u32 cid;
+};
+
+struct v4l2_flash_ops {
+	/* setup strobing the flash by hardware pin state assertion */
+	int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
+					bool enable);
+	/* convert intensity to brightness in a device specific manner */
+	enum led_brightness (*intensity_to_led_brightness)
+		(struct v4l2_flash *v4l2_flash, s32 intensity);
+	/* convert brightness to intensity in a device specific manner */
+	s32 (*led_brightness_to_intensity)
+		(struct v4l2_flash *v4l2_flash, enum led_brightness);
+};
+
+/**
+ * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
+ * @dev_name:			the name of the media entity,
+				unique in the system
+ * @intensity:			constraints for the LED in a non-flash mode
+ * @flash_faults:		bitmask of flash faults that the LED Flash class
+				device can report; corresponding LED_FAULT* bit
+				definitions are available in the header file
+				<linux/led-class-flash.h>
+ * @has_external_strobe:	external strobe capability
+ * @indicator_led:		signifies that a led is of indicator type
+ */
+struct v4l2_flash_config {
+	char dev_name[32];
+	struct led_flash_setting intensity;
+	u32 flash_faults;
+	unsigned int has_external_strobe:1;
+	unsigned int indicator_led:1;
+};
+
+/**
+ * struct v4l2_flash - Flash sub-device context
+ * @fled_cdev:		LED Flash class device controlled by this sub-device
+ * @ops:		V4L2 specific flash ops
+ * @sd:			V4L2 sub-device
+ * @hdl:		flash controls handler
+ * @ctrls:		array of pointers to controls, whose values define
+ *			the sub-device state
+ */
+struct v4l2_flash {
+	struct led_classdev_flash *fled_cdev;
+	const struct v4l2_flash_ops *ops;
+
+	struct v4l2_subdev sd;
+	struct v4l2_ctrl_handler hdl;
+	struct v4l2_ctrl *ctrls[STROBE_SOURCE + 1];
+};
+
+static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
+							struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct v4l2_flash, sd);
+}
+
+static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
+{
+	return container_of(c->handler, struct v4l2_flash, hdl);
+}
+
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+/**
+ * v4l2_flash_init - initialize V4L2 flash led sub-device
+ * @fled_cdev:	the LED Flash class device to wrap
+ * @flash_ops:	V4L2 Flash device ops
+ * @config:	initialization data for V4L2 Flash sub-device
+ *
+ * Create V4L2 Flash sub-device wrapping given LED subsystem device.
+ *
+ * Returns: A valid pointer, or, when an error occurs, the return
+ * value is encoded using ERR_PTR(). Use IS_ERR() to check and
+ * PTR_ERR() to obtain the numeric return value.
+ */
+struct v4l2_flash *v4l2_flash_init(struct led_classdev_flash *fled_cdev,
+				   const struct v4l2_flash_ops *ops,
+				   struct v4l2_flash_config *config);
+
+/**
+ * v4l2_flash_release - release V4L2 Flash sub-device
+ * @flash: the V4L2 Flash sub-device to release
+ *
+ * Release V4L2 Flash sub-device.
+ */
+void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
+
+#else
+#define v4l2_flash_init(fled_cdev, ops, config) (NULL)
+#define v4l2_flash_release(v4l2_flash)
+#endif /* CONFIG_V4L2_FLASH_LED_CLASS */
+
+#endif /* _V4L2_FLASH_H */
-- 
1.7.9.5

Re: [PATCH v6 06/10] media: Add registration helpers for V4L2 flash sub-devices

[Sakari Ailus]

Hi Jacek,

On Tue, Apr 28, 2015 at 09:18:46AM +0200, Jacek Anaszewski wrote:
...
> +enum ctrl_init_data_id {
> +	LED_MODE,
> +	TORCH_INTENSITY,
> +	FLASH_INTENSITY,
> +	INDICATOR_INTENSITY,
> +	FLASH_TIMEOUT,
> +	STROBE_SOURCE,
> +	/*
> +	 * Only above values are applicable to
> +	 * the 'ctrls' array in the struct v4l2_flash.
> +	 */
> +	FLASH_STROBE,
> +	STROBE_STOP,
> +	STROBE_STATUS,
> +	FLASH_FAULT,
> +	NUM_FLASH_CTRLS,
> +};

How about moving these to the .c file and allocating space for struct
v4l2_flash.ctrls?

I don't object this enum as such, but the names are pretty generic and
there's a single instance of using them in the header which easily can be
avoided.

With this change,

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Kind regards,

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

[PATCH v6 07/10] Documentation: leds: Add description of v4l2-flash sub-device

[Jacek Anaszewski]

This patch extends LED Flash class documention by
the description of interactions with v4l2-flash sub-device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
 Documentation/leds/leds-class-flash.txt |   47 +++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
index 19bb673..9d39133 100644
--- a/Documentation/leds/leds-class-flash.txt
+++ b/Documentation/leds/leds-class-flash.txt
@@ -20,3 +20,50 @@ Following sysfs attributes are exposed for controlling flash LED devices:
 	- max_flash_timeout
 	- flash_strobe
 	- flash_fault
+
+
+V4L2 flash wrapper for flash LEDs
+=================================
+
+A LED subsystem driver can be controlled also from the level of VideoForLinux2
+subsystem. In order to enable this CONFIG_V4L2_FLASH_LED_CLASS symbol has to
+be defined in the kernel config.
+
+The driver must call the v4l2_flash_init function to get registered in the
+V4L2 subsystem. The function takes three arguments:
+- fled_cdev : the LED Flash class device to wrap
+- ops : V4L2 specific ops
+	* external_strobe_set - defines the source of the flash LED strobe -
+		V4L2_CID_FLASH_STROBE control or external source, typically
+		a sensor, which makes it possible to synchronise the flash
+		strobe start with exposure start,
+	* intensity_to_led_brightness and led_brightness_to_intensity - perform
+		enum led_brightness <-> V4L2 intensity conversion in a device
+		specific manner - they can be used for devices with non-linear
+		LED current scale.
+- config : configuration for V4L2 Flash sub-device
+	* dev_name - the name of the media entity, unique in the system,
+	* flash_faults - bitmask of flash faults that the LED Flash class
+		device can report; corresponding LED_FAULT* bit definitions are
+		available in <linux/led-class-flash.h>,
+	* intensity - constraints for the LED in the TORCH or INDICATOR mode,
+		in microamperes,
+	* has_external_strobe - determines whether the flash strobe source
+		can be switched to external,
+	* indicator_led - signifies that a led is of indicator type, which
+		implies that it can have only two V4L2 controls:
+		V4L2_CID_FLASH_INDICATOR_INTENSITY and V4L2_CID_FLASH_FAULT.
+
+On remove the v4l2_flash_release function has to be called, which takes one
+argument - struct v4l2_flash pointer returned previously by v4l2_flash_init.
+
+Please refer to drivers/leds/leds-max77693.c for an exemplary usage of the
+v4l2 flash API.
+
+Once the V4L2 sub-device is registered by the driver which created the Media
+controller device, the sub-device node acts just as a node of a native V4L2
+flash API device would. The calls are simply routed to the LED flash API.
+
+Opening the V4L2 flash sub-device makes the LED subsystem sysfs interface
+unavailable. The interface is re-enabled after the V4L2 flash sub-device
+is closed.
-- 
1.7.9.5

Re: [PATCH v6 07/10] Documentation: leds: Add description of v4l2-flash sub-device

[Sakari Ailus]

Hi Jacek,

On Tue, Apr 28, 2015 at 09:18:47AM +0200, Jacek Anaszewski wrote:
...
> +On remove the v4l2_flash_release function has to be called, which takes one
> +argument - struct v4l2_flash pointer returned previously by v4l2_flash_init.
> +
> +Please refer to drivers/leds/leds-max77693.c for an exemplary usage of the
> +v4l2 flash API.

s/v4l2 flash API/V4L2 flash wrapper/ .

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Regards,

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

[PATCH v6 08/10] leds: max77693: add support for V4L2 Flash sub-device

[Jacek Anaszewski]

Add support for V4L2 Flash sub-device to the max77693 LED Flash class
driver. The support allows for V4L2 Flash sub-device to take the control
of the LED Flash class device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
---
 drivers/leds/leds-max77693.c |  128 ++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 122 insertions(+), 6 deletions(-)

diff --git a/drivers/leds/leds-max77693.c b/drivers/leds/leds-max77693.c
index 0dd8cb0..d49af8d 100644
--- a/drivers/leds/leds-max77693.c
+++ b/drivers/leds/leds-max77693.c
@@ -20,6 +20,7 @@
 #include <linux/regmap.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
+#include <media/v4l2-flash-led-class.h>
 
 #define MODE_OFF		0
 #define MODE_FLASH(a)		(1 << (a))
@@ -62,6 +63,8 @@ struct max77693_sub_led {
 	struct led_classdev_flash fled_cdev;
 	/* assures led-triggers compatibility */
 	struct work_struct work_brightness_set;
+	/* V4L2 Flash device */
+	struct v4l2_flash *v4l2_flash;
 
 	/* brightness cache */
 	unsigned int torch_brightness;
@@ -634,7 +637,8 @@ static int max77693_led_flash_timeout_set(
 }
 
 static int max77693_led_parse_dt(struct max77693_led_device *led,
-				struct max77693_led_config_data *cfg)
+				struct max77693_led_config_data *cfg,
+				struct device_node **sub_nodes)
 {
 	struct device *dev = &led->pdev->dev;
 	struct max77693_sub_led *sub_leds = led->sub_leds;
@@ -681,6 +685,13 @@ static int max77693_led_parse_dt(struct max77693_led_device *led,
 			return -EINVAL;
 		}
 
+		if (sub_nodes[fled_id]) {
+			dev_err(dev,
+				"Conflicting \"led-sources\" DT properties\n");
+			return -EINVAL;
+		}
+
+		sub_nodes[fled_id] = child_node;
 		sub_leds[fled_id].fled_id = fled_id;
 
 		cfg->label[fled_id] =
@@ -793,11 +804,12 @@ static void max77693_led_validate_configuration(struct max77693_led_device *led,
 }
 
 static int max77693_led_get_configuration(struct max77693_led_device *led,
-				struct max77693_led_config_data *cfg)
+				struct max77693_led_config_data *cfg,
+				struct device_node **sub_nodes)
 {
 	int ret;
 
-	ret = max77693_led_parse_dt(led, cfg);
+	ret = max77693_led_parse_dt(led, cfg, sub_nodes);
 	if (ret < 0)
 		return ret;
 
@@ -845,6 +857,66 @@ static void max77693_init_flash_settings(struct max77693_sub_led *sub_led,
 	setting->val = setting->max;
 }
 
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+
+static int max77693_led_external_strobe_set(
+				struct v4l2_flash *v4l2_flash,
+				bool enable)
+{
+	struct max77693_sub_led *sub_led =
+				flcdev_to_sub_led(v4l2_flash->fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	int ret;
+
+	mutex_lock(&led->lock);
+
+	if (enable)
+		ret = max77693_add_mode(led, MODE_FLASH_EXTERNAL(fled_id));
+	else
+		ret = max77693_clear_mode(led, MODE_FLASH_EXTERNAL(fled_id));
+
+	mutex_unlock(&led->lock);
+
+	return ret;
+}
+
+static void max77693_init_v4l2_flash_config(struct max77693_sub_led *sub_led,
+				struct max77693_led_config_data *led_cfg,
+				struct v4l2_flash_config *v4l2_sd_cfg)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	struct device *dev = &led->pdev->dev;
+	struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
+	struct i2c_client *i2c = iodev->i2c;
+	struct led_flash_setting *s;
+
+	snprintf(v4l2_sd_cfg->dev_name, sizeof(v4l2_sd_cfg->dev_name),
+		 "%s %d-%04x", sub_led->fled_cdev.led_cdev.name,
+		 i2c_adapter_id(i2c->adapter), i2c->addr);
+
+	s = &v4l2_sd_cfg->intensity;
+	s->min = TORCH_IOUT_MIN;
+	s->max = sub_led->fled_cdev.led_cdev.max_brightness * TORCH_IOUT_STEP;
+	s->step = TORCH_IOUT_STEP;
+	s->val = s->max;
+
+	/* Init flash faults config */
+	v4l2_sd_cfg->flash_faults = LED_FAULT_OVER_VOLTAGE |
+				LED_FAULT_SHORT_CIRCUIT |
+				LED_FAULT_OVER_CURRENT;
+
+	v4l2_sd_cfg->has_external_strobe = true;
+}
+
+static const struct v4l2_flash_ops v4l2_flash_ops = {
+	.external_strobe_set = max77693_led_external_strobe_set,
+};
+
+#else
+#define max77693_init_v4l2_flash_config(sub_led, led_cfg, v4l2_sd_cfg)
+#endif
+
 static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
 				struct max77693_led_config_data *led_cfg)
 {
@@ -877,12 +949,49 @@ static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
 	sub_led->flash_timeout = fled_cdev->timeout.val;
 }
 
+static int max77693_register_led(struct max77693_sub_led *sub_led,
+				 struct max77693_led_config_data *led_cfg,
+				 struct device_node *sub_node)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	struct led_classdev_flash *fled_cdev = &sub_led->fled_cdev;
+	struct device *dev = &led->pdev->dev;
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+	struct v4l2_flash_config v4l2_sd_cfg = {};
+#endif
+	int ret;
+
+	/* Register in the LED subsystem */
+	ret = led_classdev_flash_register(dev, fled_cdev);
+	if (ret < 0)
+		return ret;
+
+	max77693_init_v4l2_flash_config(sub_led, led_cfg, &v4l2_sd_cfg);
+
+	fled_cdev->led_cdev.dev->of_node = sub_node;
+
+	/* Register in the V4L2 subsystem. */
+	sub_led->v4l2_flash = v4l2_flash_init(fled_cdev, &v4l2_flash_ops,
+						&v4l2_sd_cfg);
+	if (IS_ERR(sub_led->v4l2_flash)) {
+		ret = PTR_ERR(sub_led->v4l2_flash);
+		goto err_v4l2_flash_init;
+	}
+
+	return 0;
+
+err_v4l2_flash_init:
+	led_classdev_flash_unregister(fled_cdev);
+	return ret;
+}
+
 static int max77693_led_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
 	struct max77693_led_device *led;
 	struct max77693_sub_led *sub_leds;
+	struct device_node *sub_nodes[2] = {};
 	struct max77693_led_config_data led_cfg = {};
 	int init_fled_cdev[2], i, ret;
 
@@ -896,7 +1005,7 @@ static int max77693_led_probe(struct platform_device *pdev)
 	sub_leds = led->sub_leds;
 
 	platform_set_drvdata(pdev, led);
-	ret = max77693_led_get_configuration(led, &led_cfg);
+	ret = max77693_led_get_configuration(led, &led_cfg, sub_nodes);
 	if (ret < 0)
 		return ret;
 
@@ -918,8 +1027,12 @@ static int max77693_led_probe(struct platform_device *pdev)
 		/* Initialize LED Flash class device */
 		max77693_init_fled_cdev(&sub_leds[i], &led_cfg);
 
-		/* Register LED Flash class device */
-		ret = led_classdev_flash_register(dev, &sub_leds[i].fled_cdev);
+		/*
+		 * Register LED Flash class device and corresponding
+		 * V4L2 Flash device.
+		 */
+		ret = max77693_register_led(&sub_leds[i], &led_cfg,
+						sub_nodes[i]);
 		if (ret < 0) {
 			/*
 			 * At this moment FLED1 might have been already
@@ -938,6 +1051,7 @@ err_register_led2:
 	/* It is possible than only FLED2 was to be registered */
 	if (!init_fled_cdev[FLED1])
 		goto err_register_led1;
+	v4l2_flash_release(sub_leds[FLED1].v4l2_flash);
 	led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
 err_register_led1:
 	mutex_destroy(&led->lock);
@@ -951,11 +1065,13 @@ static int max77693_led_remove(struct platform_device *pdev)
 	struct max77693_sub_led *sub_leds = led->sub_leds;
 
 	if (led->iout_joint || max77693_fled_used(led, FLED1)) {
+		v4l2_flash_release(sub_leds[FLED1].v4l2_flash);
 		led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
 		cancel_work_sync(&sub_leds[FLED1].work_brightness_set);
 	}
 
 	if (!led->iout_joint && max77693_fled_used(led, FLED2)) {
+		v4l2_flash_release(sub_leds[FLED2].v4l2_flash);
 		led_classdev_flash_unregister(&sub_leds[FLED2].fled_cdev);
 		cancel_work_sync(&sub_leds[FLED2].work_brightness_set);
 	}
-- 
1.7.9.5

Re: [PATCH v6 08/10] leds: max77693: add support for V4L2 Flash sub-device

[Sakari Ailus]

On Tue, Apr 28, 2015 at 09:18:48AM +0200, Jacek Anaszewski wrote:
> Add support for V4L2 Flash sub-device to the max77693 LED Flash class
> driver. The support allows for V4L2 Flash sub-device to take the control
> of the LED Flash class device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: Sakari Ailus <sakari.ailus@iki.fi>

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

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

[PATCH v6 09/10] DT: aat1290: Document handling external strobe sources

[Jacek Anaszewski]

This patch adds documentation for a pinctrl-names property.
The property, when present, is used for switching the source
of the strobe signal for the device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Cc: devicetree@vger.kernel.org
---
 .../devicetree/bindings/leds/leds-aat1290.txt      |   36 ++++++++++++++++++--
 1 file changed, 34 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/leds/leds-aat1290.txt b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
index ef88b9c..c05ed91 100644
--- a/Documentation/devicetree/bindings/leds/leds-aat1290.txt
+++ b/Documentation/devicetree/bindings/leds/leds-aat1290.txt
@@ -2,7 +2,9 @@
 
 The device is controlled through two pins: FL_EN and EN_SET. The pins when,
 asserted high, enable flash strobe and movie mode (max 1/2 of flash current)
-respectively.
+respectively. In order to add a capability of selecting the strobe signal source
+(e.g. CPU or camera sensor) there is an additional switch required, independent
+of the flash chip. The switch is controlled with pin control.
 
 Required properties:
 
@@ -10,6 +12,13 @@ Required properties:
 - flen-gpios : Must be device tree identifier of the flash device FL_EN pin.
 - enset-gpios : Must be device tree identifier of the flash device EN_SET pin.
 
+Optional properties:
+- pinctrl-names : Must contain entries: "default", "host", "isp". Entries
+		"default" and "host" must refer to the same pin configuration
+		node, which sets the host as a strobe signal provider. Entry
+		"isp" must refer to the pin configuration node, which sets the
+		ISP as a strobe signal provider.
+
 A discrete LED element connected to the device must be represented by a child
 node - see Documentation/devicetree/bindings/leds/common.txt.
 
@@ -25,13 +34,22 @@ Required properties of the LED child node:
 Optional properties of the LED child node:
 - label : see Documentation/devicetree/bindings/leds/common.txt
 
-Example (by Ct = 220nF, Rset = 160kohm):
+Example (by Ct = 220nF, Rset = 160kohm and exynos4412-trats2 board with
+a switch that allows for routing strobe signal either from the host or from
+the camera sensor):
+
+#include "exynos4412.dtsi"
 
 aat1290 {
 	compatible = "skyworks,aat1290";
 	flen-gpios = <&gpj1 1 GPIO_ACTIVE_HIGH>;
 	enset-gpios = <&gpj1 2 GPIO_ACTIVE_HIGH>;
 
+	pinctrl-names = "default", "host", "isp";
+	pinctrl-0 = <&camera_flash_host>;
+	pinctrl-1 = <&camera_flash_host>;
+	pinctrl-2 = <&camera_flash_isp>;
+
 	camera_flash: flash-led {
 		label = "aat1290-flash";
 		led-max-microamp = <520833>;
@@ -39,3 +57,17 @@ aat1290 {
 		flash-timeout-us = <1940000>;
 	};
 };
+
+&pinctrl_0 {
+	camera_flash_host: camera-flash-host {
+		samsung,pins = "gpj1-0";
+		samsung,pin-function = <1>;
+		samsung,pin-val = <0>;
+	};
+
+	camera_flash_isp: camera-flash-isp {
+		samsung,pins = "gpj1-0";
+		samsung,pin-function = <1>;
+		samsung,pin-val = <1>;
+	};
+};
-- 
1.7.9.5

[PATCH v6 10/10] leds: aat1290: add support for V4L2 Flash sub-device

[Jacek Anaszewski]

Add support for V4L2 Flash sub-device to the aat1290 LED Flash class
driver. The support allows for V4L2 Flash sub-device to take the control
of the LED Flash class device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
---
 drivers/leds/Kconfig        |    1 +
 drivers/leds/leds-aat1290.c |  137 +++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 132 insertions(+), 6 deletions(-)

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index dd7834c..874df63 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -47,6 +47,7 @@ config LEDS_AAT1290
 	depends on LEDS_CLASS_FLASH
 	depends on GPIOLIB
 	depends on OF
+	depends on PINCTRL
 	help
 	 This option enables support for the LEDs on the AAT1290.
 
diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
index 03e5b96..f37f848 100644
--- a/drivers/leds/leds-aat1290.c
+++ b/drivers/leds/leds-aat1290.c
@@ -17,9 +17,11 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
+#include <media/v4l2-flash-led-class.h>
 
 #define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
 #define AAT1290_MAX_MM_CURR_PERCENT_0	16
@@ -52,6 +54,8 @@ struct aat1290_led_config_data {
 	u32 max_flash_current;
 	/* maximum flash timeout */
 	u32 max_flash_tm;
+	/* external strobe capability */
+	bool has_external_strobe;
 	/* max LED brightness level */
 	enum led_brightness max_brightness;
 };
@@ -64,6 +68,8 @@ struct aat1290_led {
 
 	/* corresponding LED Flash class device */
 	struct led_classdev_flash fled_cdev;
+	/* V4L2 Flash device */
+	struct v4l2_flash *v4l2_flash;
 
 	/* FLEN pin */
 	struct gpio_desc *gpio_fl_en;
@@ -230,11 +236,15 @@ static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
 }
 
 static int aat1290_led_parse_dt(struct aat1290_led *led,
-			struct aat1290_led_config_data *cfg)
+			struct aat1290_led_config_data *cfg,
+			struct device_node **sub_node)
 {
 	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
 	struct device *dev = &led->pdev->dev;
 	struct device_node *child_node;
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+	struct pinctrl *pinctrl;
+#endif
 	int ret = 0;
 
 	led->gpio_fl_en = devm_gpiod_get(dev, "flen");
@@ -251,6 +261,17 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
 		return ret;
 	}
 
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
+	if (IS_ERR(pinctrl)) {
+		cfg->has_external_strobe = false;
+		dev_info(dev,
+			 "No support for external strobe detected.\n");
+	} else {
+		cfg->has_external_strobe = true;
+	}
+#endif
+
 	child_node = of_get_next_available_child(dev->of_node, NULL);
 	if (!child_node) {
 		dev_err(dev, "No DT child node found for connected LED.\n");
@@ -288,6 +309,8 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
 
 	of_node_put(child_node);
 
+	*sub_node = child_node;
+
 	return ret;
 }
 
@@ -316,7 +339,8 @@ int init_mm_current_scale(struct aat1290_led *led,
 	int i, max_mm_current =
 			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
 
-	led->mm_current_scale = kzalloc(sizeof(max_mm_current_percent),
+	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
+					sizeof(max_mm_current_percent),
 					GFP_KERNEL);
 	if (!led->mm_current_scale)
 		return -ENOMEM;
@@ -329,11 +353,12 @@ int init_mm_current_scale(struct aat1290_led *led,
 }
 
 static int aat1290_led_get_configuration(struct aat1290_led *led,
-					struct aat1290_led_config_data *cfg)
+					struct aat1290_led_config_data *cfg,
+					struct device_node **sub_node)
 {
 	int ret;
 
-	ret = aat1290_led_parse_dt(led, cfg);
+	ret = aat1290_led_parse_dt(led, cfg, sub_node);
 	if (ret < 0)
 		return ret;
 	/*
@@ -346,7 +371,10 @@ static int aat1290_led_get_configuration(struct aat1290_led *led,
 
 	aat1290_led_validate_mm_current(led, cfg);
 
-	kfree(led->mm_current_scale);
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+#else
+	devm_kfree(&led->pdev->dev, led->mm_current_scale);
+#endif
 
 	return 0;
 }
@@ -365,6 +393,83 @@ static void aat1290_init_flash_timeout(struct aat1290_led *led,
 	setting->val = setting->max;
 }
 
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+enum led_brightness aat1290_intensity_to_brightness(
+					struct v4l2_flash *v4l2_flash,
+					s32 intensity)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
+	int i;
+
+	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
+		if (intensity >= led->mm_current_scale[i])
+			return i + 1;
+
+	return 1;
+}
+
+s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
+					enum led_brightness brightness)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
+
+	return led->mm_current_scale[brightness - 1];
+}
+
+static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
+						bool enable)
+{
+	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
+	struct pinctrl *pinctrl;
+
+	gpiod_direction_output(led->gpio_fl_en, 0);
+	gpiod_direction_output(led->gpio_en_set, 0);
+
+	led->movie_mode = false;
+	led_cdev->brightness = 0;
+
+	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
+						enable ? "isp" : "host");
+	if (IS_ERR(pinctrl)) {
+		dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
+		return PTR_ERR(pinctrl);
+	}
+
+	return 0;
+}
+
+static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
+					struct aat1290_led_config_data *led_cfg,
+					struct v4l2_flash_config *v4l2_sd_cfg)
+{
+	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
+	struct led_flash_setting *s;
+
+	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
+		sizeof(v4l2_sd_cfg->dev_name));
+
+	s = &v4l2_sd_cfg->intensity;
+	s->min = led->mm_current_scale[0];
+	s->max = led_cfg->max_mm_current;
+	s->step = 1;
+	s->val = s->max;
+
+	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
+}
+
+static const struct v4l2_flash_ops v4l2_flash_ops = {
+	.external_strobe_set = aat1290_led_external_strobe_set,
+	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
+	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
+};
+#else
+#define aat1290_init_v4l2_flash_config(led, led_cfg, v4l2_sd_cfg)
+#endif
+
 static const struct led_flash_ops flash_ops = {
 	.strobe_set = aat1290_led_flash_strobe_set,
 	.timeout_set = aat1290_led_flash_timeout_set,
@@ -373,10 +478,14 @@ static const struct led_flash_ops flash_ops = {
 static int aat1290_led_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct device_node *sub_node = NULL;
 	struct aat1290_led *led;
 	struct led_classdev *led_cdev;
 	struct led_classdev_flash *fled_cdev;
 	struct aat1290_led_config_data led_cfg = {};
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+	struct v4l2_flash_config v4l2_sd_cfg = {};
+#endif
 	int ret;
 
 	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
@@ -390,7 +499,7 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	fled_cdev->ops = &flash_ops;
 	led_cdev = &fled_cdev->led_cdev;
 
-	ret = aat1290_led_get_configuration(led, &led_cfg);
+	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
 	if (ret < 0)
 		return ret;
 
@@ -410,8 +519,23 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_flash_register;
 
+	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
+
+	led_cdev->dev->of_node = sub_node;
+
+	/* Create V4L2 Flash subdev. */
+	led->v4l2_flash = v4l2_flash_init(fled_cdev,
+					  &v4l2_flash_ops,
+					  &v4l2_sd_cfg);
+	if (IS_ERR(led->v4l2_flash)) {
+		ret = PTR_ERR(led->v4l2_flash);
+		goto error_v4l2_flash_init;
+	}
+
 	return 0;
 
+error_v4l2_flash_init:
+	led_classdev_flash_unregister(fled_cdev);
 err_flash_register:
 	mutex_destroy(&led->lock);
 
@@ -422,6 +546,7 @@ static int aat1290_led_remove(struct platform_device *pdev)
 {
 	struct aat1290_led *led = platform_get_drvdata(pdev);
 
+	v4l2_flash_release(led->v4l2_flash);
 	led_classdev_flash_unregister(&led->fled_cdev);
 	cancel_work_sync(&led->work_brightness_set);
 
-- 
1.7.9.5

Re: [PATCH v6 10/10] leds: aat1290: add support for V4L2 Flash sub-device

[Sakari Ailus]

Hi Jacek,

On Tue, Apr 28, 2015 at 09:18:50AM +0200, Jacek Anaszewski wrote:
> Add support for V4L2 Flash sub-device to the aat1290 LED Flash class
> driver. The support allows for V4L2 Flash sub-device to take the control
> of the LED Flash class device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Cc: Sakari Ailus <sakari.ailus@iki.fi>
> ---
>  drivers/leds/Kconfig        |    1 +
>  drivers/leds/leds-aat1290.c |  137 +++++++++++++++++++++++++++++++++++++++++--
>  2 files changed, 132 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index dd7834c..874df63 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -47,6 +47,7 @@ config LEDS_AAT1290
>  	depends on LEDS_CLASS_FLASH
>  	depends on GPIOLIB
>  	depends on OF
> +	depends on PINCTRL
>  	help
>  	 This option enables support for the LEDs on the AAT1290.
>  
> diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
> index 03e5b96..f37f848 100644
> --- a/drivers/leds/leds-aat1290.c
> +++ b/drivers/leds/leds-aat1290.c
> @@ -17,9 +17,11 @@
>  #include <linux/module.h>
>  #include <linux/mutex.h>
>  #include <linux/of.h>
> +#include <linux/pinctrl/consumer.h>
>  #include <linux/platform_device.h>
>  #include <linux/slab.h>
>  #include <linux/workqueue.h>
> +#include <media/v4l2-flash-led-class.h>
>  
>  #define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
>  #define AAT1290_MAX_MM_CURR_PERCENT_0	16
> @@ -52,6 +54,8 @@ struct aat1290_led_config_data {
>  	u32 max_flash_current;
>  	/* maximum flash timeout */
>  	u32 max_flash_tm;
> +	/* external strobe capability */
> +	bool has_external_strobe;
>  	/* max LED brightness level */
>  	enum led_brightness max_brightness;
>  };
> @@ -64,6 +68,8 @@ struct aat1290_led {
>  
>  	/* corresponding LED Flash class device */
>  	struct led_classdev_flash fled_cdev;
> +	/* V4L2 Flash device */
> +	struct v4l2_flash *v4l2_flash;
>  
>  	/* FLEN pin */
>  	struct gpio_desc *gpio_fl_en;
> @@ -230,11 +236,15 @@ static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
>  }
>  
>  static int aat1290_led_parse_dt(struct aat1290_led *led,
> -			struct aat1290_led_config_data *cfg)
> +			struct aat1290_led_config_data *cfg,
> +			struct device_node **sub_node)
>  {
>  	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
>  	struct device *dev = &led->pdev->dev;
>  	struct device_node *child_node;
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +	struct pinctrl *pinctrl;
> +#endif
>  	int ret = 0;
>  
>  	led->gpio_fl_en = devm_gpiod_get(dev, "flen");
> @@ -251,6 +261,17 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
>  		return ret;
>  	}
>  
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
> +	if (IS_ERR(pinctrl)) {
> +		cfg->has_external_strobe = false;
> +		dev_info(dev,
> +			 "No support for external strobe detected.\n");
> +	} else {
> +		cfg->has_external_strobe = true;
> +	}
> +#endif
> +
>  	child_node = of_get_next_available_child(dev->of_node, NULL);
>  	if (!child_node) {
>  		dev_err(dev, "No DT child node found for connected LED.\n");
> @@ -288,6 +309,8 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
>  
>  	of_node_put(child_node);
>  
> +	*sub_node = child_node;
> +
>  	return ret;
>  }
>  
> @@ -316,7 +339,8 @@ int init_mm_current_scale(struct aat1290_led *led,
>  	int i, max_mm_current =
>  			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
>  
> -	led->mm_current_scale = kzalloc(sizeof(max_mm_current_percent),
> +	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
> +					sizeof(max_mm_current_percent),
>  					GFP_KERNEL);
>  	if (!led->mm_current_scale)
>  		return -ENOMEM;
> @@ -329,11 +353,12 @@ int init_mm_current_scale(struct aat1290_led *led,
>  }
>  
>  static int aat1290_led_get_configuration(struct aat1290_led *led,
> -					struct aat1290_led_config_data *cfg)
> +					struct aat1290_led_config_data *cfg,
> +					struct device_node **sub_node)
>  {
>  	int ret;
>  
> -	ret = aat1290_led_parse_dt(led, cfg);
> +	ret = aat1290_led_parse_dt(led, cfg, sub_node);
>  	if (ret < 0)
>  		return ret;
>  	/*
> @@ -346,7 +371,10 @@ static int aat1290_led_get_configuration(struct aat1290_led *led,
>  
>  	aat1290_led_validate_mm_current(led, cfg);
>  
> -	kfree(led->mm_current_scale);
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +#else
> +	devm_kfree(&led->pdev->dev, led->mm_current_scale);
> +#endif
>  
>  	return 0;
>  }
> @@ -365,6 +393,83 @@ static void aat1290_init_flash_timeout(struct aat1290_led *led,
>  	setting->val = setting->max;
>  }
>  
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +enum led_brightness aat1290_intensity_to_brightness(
> +					struct v4l2_flash *v4l2_flash,
> +					s32 intensity)
> +{
> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
> +	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
> +	int i;
> +
> +	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
> +		if (intensity >= led->mm_current_scale[i])
> +			return i + 1;
> +
> +	return 1;
> +}
> +
> +s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
> +					enum led_brightness brightness)
> +{
> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
> +	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
> +
> +	return led->mm_current_scale[brightness - 1];
> +}
> +
> +static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
> +						bool enable)
> +{
> +	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
> +	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
> +	struct pinctrl *pinctrl;
> +
> +	gpiod_direction_output(led->gpio_fl_en, 0);
> +	gpiod_direction_output(led->gpio_en_set, 0);
> +
> +	led->movie_mode = false;
> +	led_cdev->brightness = 0;
> +
> +	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
> +						enable ? "isp" : "host");
> +	if (IS_ERR(pinctrl)) {
> +		dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
> +		return PTR_ERR(pinctrl);
> +	}
> +
> +	return 0;
> +}
> +
> +static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
> +					struct aat1290_led_config_data *led_cfg,
> +					struct v4l2_flash_config *v4l2_sd_cfg)
> +{
> +	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
> +	struct led_flash_setting *s;
> +
> +	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
> +		sizeof(v4l2_sd_cfg->dev_name));
> +
> +	s = &v4l2_sd_cfg->intensity;
> +	s->min = led->mm_current_scale[0];
> +	s->max = led_cfg->max_mm_current;
> +	s->step = 1;
> +	s->val = s->max;
> +
> +	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
> +}
> +
> +static const struct v4l2_flash_ops v4l2_flash_ops = {
> +	.external_strobe_set = aat1290_led_external_strobe_set,
> +	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
> +	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
> +};
> +#else
> +#define aat1290_init_v4l2_flash_config(led, led_cfg, v4l2_sd_cfg)
> +#endif
> +
>  static const struct led_flash_ops flash_ops = {
>  	.strobe_set = aat1290_led_flash_strobe_set,
>  	.timeout_set = aat1290_led_flash_timeout_set,
> @@ -373,10 +478,14 @@ static const struct led_flash_ops flash_ops = {
>  static int aat1290_led_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
> +	struct device_node *sub_node = NULL;
>  	struct aat1290_led *led;
>  	struct led_classdev *led_cdev;
>  	struct led_classdev_flash *fled_cdev;
>  	struct aat1290_led_config_data led_cfg = {};
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +	struct v4l2_flash_config v4l2_sd_cfg = {};
> +#endif
>  	int ret;
>  
>  	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
> @@ -390,7 +499,7 @@ static int aat1290_led_probe(struct platform_device *pdev)
>  	fled_cdev->ops = &flash_ops;
>  	led_cdev = &fled_cdev->led_cdev;
>  
> -	ret = aat1290_led_get_configuration(led, &led_cfg);
> +	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
>  	if (ret < 0)
>  		return ret;
>  
> @@ -410,8 +519,23 @@ static int aat1290_led_probe(struct platform_device *pdev)
>  	if (ret < 0)
>  		goto err_flash_register;
>  
> +	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
> +
> +	led_cdev->dev->of_node = sub_node;

What's the reason for this? I can't immediately see how this is being used.

There's also a problem with references, you should grab it here and release
when it's no longer used.

> +
> +	/* Create V4L2 Flash subdev. */
> +	led->v4l2_flash = v4l2_flash_init(fled_cdev,
> +					  &v4l2_flash_ops,
> +					  &v4l2_sd_cfg);
> +	if (IS_ERR(led->v4l2_flash)) {
> +		ret = PTR_ERR(led->v4l2_flash);
> +		goto error_v4l2_flash_init;
> +	}
> +
>  	return 0;
>  
> +error_v4l2_flash_init:
> +	led_classdev_flash_unregister(fled_cdev);
>  err_flash_register:
>  	mutex_destroy(&led->lock);
>  
> @@ -422,6 +546,7 @@ static int aat1290_led_remove(struct platform_device *pdev)
>  {
>  	struct aat1290_led *led = platform_get_drvdata(pdev);
>  
> +	v4l2_flash_release(led->v4l2_flash);
>  	led_classdev_flash_unregister(&led->fled_cdev);
>  	cancel_work_sync(&led->work_brightness_set);
>  

-- 
Kind regards,

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

Re: [PATCH v6 10/10] leds: aat1290: add support for V4L2 Flash sub-device

[Jacek Anaszewski]

Hi Sakari,

On 04/28/2015 04:02 PM, Sakari Ailus wrote:
> Hi Jacek,
>
> On Tue, Apr 28, 2015 at 09:18:50AM +0200, Jacek Anaszewski wrote:
>> Add support for V4L2 Flash sub-device to the aat1290 LED Flash class
>> driver. The support allows for V4L2 Flash sub-device to take the control
>> of the LED Flash class device.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>> Cc: Sakari Ailus <sakari.ailus@iki.fi>
>> ---
>>   drivers/leds/Kconfig        |    1 +
>>   drivers/leds/leds-aat1290.c |  137 +++++++++++++++++++++++++++++++++++++++++--
>>   2 files changed, 132 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>> index dd7834c..874df63 100644
>> --- a/drivers/leds/Kconfig
>> +++ b/drivers/leds/Kconfig
>> @@ -47,6 +47,7 @@ config LEDS_AAT1290
>>   	depends on LEDS_CLASS_FLASH
>>   	depends on GPIOLIB
>>   	depends on OF
>> +	depends on PINCTRL
>>   	help
>>   	 This option enables support for the LEDs on the AAT1290.
>>
>> diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
>> index 03e5b96..f37f848 100644
>> --- a/drivers/leds/leds-aat1290.c
>> +++ b/drivers/leds/leds-aat1290.c
>> @@ -17,9 +17,11 @@
>>   #include <linux/module.h>
>>   #include <linux/mutex.h>
>>   #include <linux/of.h>
>> +#include <linux/pinctrl/consumer.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/slab.h>
>>   #include <linux/workqueue.h>
>> +#include <media/v4l2-flash-led-class.h>
>>
>>   #define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
>>   #define AAT1290_MAX_MM_CURR_PERCENT_0	16
>> @@ -52,6 +54,8 @@ struct aat1290_led_config_data {
>>   	u32 max_flash_current;
>>   	/* maximum flash timeout */
>>   	u32 max_flash_tm;
>> +	/* external strobe capability */
>> +	bool has_external_strobe;
>>   	/* max LED brightness level */
>>   	enum led_brightness max_brightness;
>>   };
>> @@ -64,6 +68,8 @@ struct aat1290_led {
>>
>>   	/* corresponding LED Flash class device */
>>   	struct led_classdev_flash fled_cdev;
>> +	/* V4L2 Flash device */
>> +	struct v4l2_flash *v4l2_flash;
>>
>>   	/* FLEN pin */
>>   	struct gpio_desc *gpio_fl_en;
>> @@ -230,11 +236,15 @@ static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
>>   }
>>
>>   static int aat1290_led_parse_dt(struct aat1290_led *led,
>> -			struct aat1290_led_config_data *cfg)
>> +			struct aat1290_led_config_data *cfg,
>> +			struct device_node **sub_node)
>>   {
>>   	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
>>   	struct device *dev = &led->pdev->dev;
>>   	struct device_node *child_node;
>> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
>> +	struct pinctrl *pinctrl;
>> +#endif
>>   	int ret = 0;
>>
>>   	led->gpio_fl_en = devm_gpiod_get(dev, "flen");
>> @@ -251,6 +261,17 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
>>   		return ret;
>>   	}
>>
>> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
>> +	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
>> +	if (IS_ERR(pinctrl)) {
>> +		cfg->has_external_strobe = false;
>> +		dev_info(dev,
>> +			 "No support for external strobe detected.\n");
>> +	} else {
>> +		cfg->has_external_strobe = true;
>> +	}
>> +#endif
>> +
>>   	child_node = of_get_next_available_child(dev->of_node, NULL);
>>   	if (!child_node) {
>>   		dev_err(dev, "No DT child node found for connected LED.\n");
>> @@ -288,6 +309,8 @@ static int aat1290_led_parse_dt(struct aat1290_led *led,
>>
>>   	of_node_put(child_node);
>>
>> +	*sub_node = child_node;
>> +
>>   	return ret;
>>   }
>>
>> @@ -316,7 +339,8 @@ int init_mm_current_scale(struct aat1290_led *led,
>>   	int i, max_mm_current =
>>   			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
>>
>> -	led->mm_current_scale = kzalloc(sizeof(max_mm_current_percent),
>> +	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
>> +					sizeof(max_mm_current_percent),
>>   					GFP_KERNEL);
>>   	if (!led->mm_current_scale)
>>   		return -ENOMEM;
>> @@ -329,11 +353,12 @@ int init_mm_current_scale(struct aat1290_led *led,
>>   }
>>
>>   static int aat1290_led_get_configuration(struct aat1290_led *led,
>> -					struct aat1290_led_config_data *cfg)
>> +					struct aat1290_led_config_data *cfg,
>> +					struct device_node **sub_node)
>>   {
>>   	int ret;
>>
>> -	ret = aat1290_led_parse_dt(led, cfg);
>> +	ret = aat1290_led_parse_dt(led, cfg, sub_node);
>>   	if (ret < 0)
>>   		return ret;
>>   	/*
>> @@ -346,7 +371,10 @@ static int aat1290_led_get_configuration(struct aat1290_led *led,
>>
>>   	aat1290_led_validate_mm_current(led, cfg);
>>
>> -	kfree(led->mm_current_scale);
>> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
>> +#else
>> +	devm_kfree(&led->pdev->dev, led->mm_current_scale);
>> +#endif
>>
>>   	return 0;
>>   }
>> @@ -365,6 +393,83 @@ static void aat1290_init_flash_timeout(struct aat1290_led *led,
>>   	setting->val = setting->max;
>>   }
>>
>> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
>> +enum led_brightness aat1290_intensity_to_brightness(
>> +					struct v4l2_flash *v4l2_flash,
>> +					s32 intensity)
>> +{
>> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
>> +	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
>> +	int i;
>> +
>> +	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
>> +		if (intensity >= led->mm_current_scale[i])
>> +			return i + 1;
>> +
>> +	return 1;
>> +}
>> +
>> +s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
>> +					enum led_brightness brightness)
>> +{
>> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
>> +	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
>> +
>> +	return led->mm_current_scale[brightness - 1];
>> +}
>> +
>> +static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
>> +						bool enable)
>> +{
>> +	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
>> +	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
>> +	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
>> +	struct pinctrl *pinctrl;
>> +
>> +	gpiod_direction_output(led->gpio_fl_en, 0);
>> +	gpiod_direction_output(led->gpio_en_set, 0);
>> +
>> +	led->movie_mode = false;
>> +	led_cdev->brightness = 0;
>> +
>> +	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
>> +						enable ? "isp" : "host");
>> +	if (IS_ERR(pinctrl)) {
>> +		dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
>> +		return PTR_ERR(pinctrl);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
>> +					struct aat1290_led_config_data *led_cfg,
>> +					struct v4l2_flash_config *v4l2_sd_cfg)
>> +{
>> +	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
>> +	struct led_flash_setting *s;
>> +
>> +	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
>> +		sizeof(v4l2_sd_cfg->dev_name));
>> +
>> +	s = &v4l2_sd_cfg->intensity;
>> +	s->min = led->mm_current_scale[0];
>> +	s->max = led_cfg->max_mm_current;
>> +	s->step = 1;
>> +	s->val = s->max;
>> +
>> +	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
>> +}
>> +
>> +static const struct v4l2_flash_ops v4l2_flash_ops = {
>> +	.external_strobe_set = aat1290_led_external_strobe_set,
>> +	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
>> +	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
>> +};
>> +#else
>> +#define aat1290_init_v4l2_flash_config(led, led_cfg, v4l2_sd_cfg)
>> +#endif
>> +
>>   static const struct led_flash_ops flash_ops = {
>>   	.strobe_set = aat1290_led_flash_strobe_set,
>>   	.timeout_set = aat1290_led_flash_timeout_set,
>> @@ -373,10 +478,14 @@ static const struct led_flash_ops flash_ops = {
>>   static int aat1290_led_probe(struct platform_device *pdev)
>>   {
>>   	struct device *dev = &pdev->dev;
>> +	struct device_node *sub_node = NULL;
>>   	struct aat1290_led *led;
>>   	struct led_classdev *led_cdev;
>>   	struct led_classdev_flash *fled_cdev;
>>   	struct aat1290_led_config_data led_cfg = {};
>> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
>> +	struct v4l2_flash_config v4l2_sd_cfg = {};
>> +#endif
>>   	int ret;
>>
>>   	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
>> @@ -390,7 +499,7 @@ static int aat1290_led_probe(struct platform_device *pdev)
>>   	fled_cdev->ops = &flash_ops;
>>   	led_cdev = &fled_cdev->led_cdev;
>>
>> -	ret = aat1290_led_get_configuration(led, &led_cfg);
>> +	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
>>   	if (ret < 0)
>>   		return ret;
>>
>> @@ -410,8 +519,23 @@ static int aat1290_led_probe(struct platform_device *pdev)
>>   	if (ret < 0)
>>   		goto err_flash_register;
>>
>> +	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
>> +
>> +	led_cdev->dev->of_node = sub_node;
>
> What's the reason for this? I can't immediately see how this is being used.

The of_node is used for async sub-device registration. There is a call
made in v4l2_sync_belongs:
	match(sd->dev, asd).

In this case match_of is used which does the comparison:
dev->of_node == asd->match.of.node.

In v4l2_flash_init an assignment is made: sd->dev = led_cdev->dev

> There's also a problem with references, you should grab it here and release
> when it's no longer used.

The reference is grabbed in v4l2_flash_init.

>> +
>> +	/* Create V4L2 Flash subdev. */
>> +	led->v4l2_flash = v4l2_flash_init(fled_cdev,
>> +					  &v4l2_flash_ops,
>> +					  &v4l2_sd_cfg);
>> +	if (IS_ERR(led->v4l2_flash)) {
>> +		ret = PTR_ERR(led->v4l2_flash);
>> +		goto error_v4l2_flash_init;
>> +	}
>> +
>>   	return 0;
>>
>> +error_v4l2_flash_init:
>> +	led_classdev_flash_unregister(fled_cdev);
>>   err_flash_register:
>>   	mutex_destroy(&led->lock);
>>
>> @@ -422,6 +546,7 @@ static int aat1290_led_remove(struct platform_device *pdev)
>>   {
>>   	struct aat1290_led *led = platform_get_drvdata(pdev);
>>
>> +	v4l2_flash_release(led->v4l2_flash);
>>   	led_classdev_flash_unregister(&led->fled_cdev);
>>   	cancel_work_sync(&led->work_brightness_set);
>>
>


-- 
Best Regards,
Jacek Anaszewski