leds: add new LP5562 LED driver

LP5562 can drive up to 4 channels, RGB and White.
LEDs can be controlled directly via the led class control interface.

 LP55xx common driver
  LP5562 is one of LP55xx family device, so LP55xx common code are used.
  On the other hand, chip specific configuration is defined in the structure
  'lp55xx_device_config'

 LED pattern data
  LP5562 has also internal program memory which is used for running various LED
  patterns. LP5562 driver supports the firmware interface and the predefined
  pattern data as well.

 LP5562 device attributes: 'led_pattern' and 'engine_mux'
  A 'led_pattern' is an index code which runs the predefined pattern data.
  And 'engine_mux' is updated with the firmware interface is activated.
  Detailed description has been updated in the documentation files,
  'leds-lp55xx.txt' and 'leds-lp5562.txt'.

 Changes on the header file
  LP5562 configurable definitions are added.
  Pattern RGB data is fixed as constant value.
  (No side effect on other devices, LP5521 or LP5523.)

(cooloney@gmail.com: remove redundant mutex_unlock(). Reported by Dan
Carpenter <dan.carpenter@oracle.com>)
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

Documentation/leds/00-INDEX

@@ -6,6 +6,8 @@ leds-lp5521.txt
 	- notes on how to use the leds-lp5521 driver.
 leds-lp5523.txt
 	- notes on how to use the leds-lp5523 driver.
+leds-lp5562.txt
+	- notes on how to use the leds-lp5562 driver.
 leds-lp55xx.txt
 	- description about lp55xx common driver.
 leds-lm3556.txt

Documentation/leds/leds-lp5562.txt

+Kernel driver for LP5562
+========================
+
+* TI LP5562 LED Driver
+
+Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+
+Description
+
+  LP5562 can drive up to 4 channels. R/G/B and White.
+  LEDs can be controlled directly via the led class control interface.
+
+  All four channels can be also controlled using the engine micro programs.
+  LP5562 has the internal program memory for running various LED patterns.
+  For the details, please refer to 'firmware' section in leds-lp55xx.txt
+
+Device attribute: engine_mux
+
+  3 Engines are allocated in LP5562, but the number of channel is 4.
+  Therefore each channel should be mapped to the engine number.
+  Value : RGB or W
+
+  This attribute is used for programming LED data with the firmware interface.
+  Unlike the LP5521/LP5523/55231, LP5562 has unique feature for the engine mux,
+  so additional sysfs is required.
+
+  LED Map
+  Red   ... Engine 1 (fixed)
+  Green ... Engine 2 (fixed)
+  Blue  ... Engine 3 (fixed)
+  White ... Engine 1 or 2 or 3 (selective)
+
+How to load the program data using engine_mux
+
+  Before loading the LP5562 program data, engine_mux should be written between
+  the engine selection and loading the firmware.
+  Engine mux has two different mode, RGB and W.
+  RGB is used for loading RGB program data, W is used for W program data.
+
+  For example, run blinking green channel pattern,
+  echo 2 > /sys/bus/i2c/devices/xxxx/select_engine     # 2 is for green channel
+  echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux    # engine mux for RGB
+  echo 1 > /sys/class/firmware/lp5562/loading
+  echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
+  echo 0 > /sys/class/firmware/lp5562/loading
+  echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
+
+  To run a blinking white pattern,
+  echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
+  echo "W" > /sys/bus/i2c/devices/xxxx/engine_mux
+  echo 1 > /sys/class/firmware/lp5562/loading
+  echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
+  echo 0 > /sys/class/firmware/lp5562/loading
+  echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
+
+How to load the predefined patterns
+
+  Please refer to 'leds-lp55xx.txt"
+
+Setting Current of Each Channel
+
+  Like LP5521 and LP5523/55231, LP5562 provides LED current settings.
+  The 'led_current' and 'max_current' are used.
+
+(Example of Platform data)
+
+To configure the platform specific data, lp55xx_platform_data structure is used.
+
+static struct lp55xx_led_config lp5562_led_config[] = {
+	{
+		.name 		= "R",
+		.chan_nr	= 0,
+		.led_current	= 20,
+		.max_current	= 40,
+	},
+	{
+		.name 		= "G",
+		.chan_nr	= 1,
+		.led_current	= 20,
+		.max_current	= 40,
+	},
+	{
+		.name 		= "B",
+		.chan_nr	= 2,
+		.led_current	= 20,
+		.max_current	= 40,
+	},
+	{
+		.name 		= "W",
+		.chan_nr	= 3,
+		.led_current	= 20,
+		.max_current	= 40,
+	},
+};
+
+static int lp5562_setup(void)
+{
+	/* setup HW resources */
+}
+
+static void lp5562_release(void)
+{
+	/* Release HW resources */
+}
+
+static void lp5562_enable(bool state)
+{
+	/* Control of chip enable signal */
+}
+
+static struct lp55xx_platform_data lp5562_platform_data = {
+        .led_config     = lp5562_led_config,
+        .num_channels   = ARRAY_SIZE(lp5562_led_config),
+        .setup_resources   = lp5562_setup,
+        .release_resources = lp5562_release,
+        .enable            = lp5562_enable,
+};
+
+If the current is set to 0 in the platform data, that channel is
+disabled and it is not visible in the sysfs.
+
+The 'update_config' : CONFIG register (ADDR 08h)
+This value is platform-specific data.
+If update_config is not defined, the CONFIG register is set with
+'LP5562_PWRSAVE_EN | LP5562_CLK_AUTO'.
+(Enable auto-powersave, set automatic clock source selection)
+
+#define LP5562_CONFIGS	(LP5562_PWM_HF | LP5562_PWRSAVE_EN | \
+			 LP5562_CLK_SRC_EXT)
+
+static struct lp55xx_platform_data lp5562_pdata = {
+	.led_config = lp5562_led_config,
+	.num_channels = ARRAY_SIZE(lp5562_led_config),
+	.update_config = LP5562_CONFIGS,
+};

Documentation/leds/leds-lp55xx.txt

@@ -5,7 +5,7 @@ Authors: Milo(Woogyom) Kim <milo.kim@ti.com>
 
 Description
 -----------
-LP5521, LP5523/55231 have common features as below.
+LP5521, LP5523/55231 and LP5562 have common features as below.
 
   Register access via the I2C
   Device initialization/deinitialization
@@ -116,3 +116,47 @@ To support this, 'run_engine' and 'firmware_cb' are configurable in each driver.
 run_engine  : Control the selected engine
 firmware_cb : The callback function after loading the firmware is done.
               Chip specific commands for loading and updating program memory.
+
+( Predefined pattern data )
+
+Without the firmware interface, LP55xx driver provides another method for
+loading a LED pattern. That is 'predefined' pattern.
+A predefined pattern is defined in the platform data and load it(or them)
+via the sysfs if needed.
+To use the predefined pattern concept, 'patterns' and 'num_patterns' should be
+configured.
+
+  Example of predefined pattern data:
+
+  /* mode_1: blinking data */
+  static const u8 mode_1[] = {
+		0x40, 0x00, 0x60, 0x00, 0x40, 0xFF, 0x60, 0x00,
+		};
+
+  /* mode_2: always on */
+  static const u8 mode_2[] = { 0x40, 0xFF, };
+
+  struct lp55xx_predef_pattern board_led_patterns[] = {
+	{
+		.r = mode_1,
+		.size_r = ARRAY_SIZE(mode_1),
+	},
+	{
+		.b = mode_2,
+		.size_b = ARRAY_SIZE(mode_2),
+	},
+  }
+
+  struct lp55xx_platform_data lp5562_pdata = {
+  ...
+	.patterns      = board_led_patterns,
+	.num_patterns  = ARRAY_SIZE(board_led_patterns),
+  };
+
+Then, mode_1 and mode_2 can be run via through the sysfs.
+
+  echo 1 > /sys/bus/i2c/devices/xxxx/led_pattern    # red blinking LED pattern
+  echo 2 > /sys/bus/i2c/devices/xxxx/led_pattern    # blue LED always on
+
+To stop running pattern,
+  echo 0 > /sys/bus/i2c/devices/xxxx/led_pattern

drivers/leds/Kconfig

@@ -194,8 +194,8 @@ config LEDS_LP3944
 	  module will be called leds-lp3944.
 
 config LEDS_LP55XX_COMMON
-	tristate "Common Driver for TI/National LP5521 and LP5523/55231"
-	depends on LEDS_LP5521 || LEDS_LP5523
+	tristate "Common Driver for TI/National LP5521, LP5523/55231 and LP5562"
+	depends on LEDS_LP5521 || LEDS_LP5523 || LEDS_LP5562
 	select FW_LOADER
 	help
 	  This option supports common operations for LP5521 and LP5523/55231
@@ -222,6 +222,16 @@ config LEDS_LP5523
 	  Driver provides direct control via LED class and interface for
 	  programming the engines.
 
+config LEDS_LP5562
+	tristate "LED Support for TI LP5562 LED driver chip"
+	depends on LEDS_CLASS && I2C
+	select LEDS_LP55XX_COMMON
+	help
+	  If you say yes here you get support for TI LP5562 LED driver.
+	  It is 4 channels chip with programmable engines.
+	  Driver provides direct control via LED class and interface for
+	  programming the engines.
+
 config LEDS_LP8788
 	tristate "LED support for the TI LP8788 PMIC"
 	depends on LEDS_CLASS

drivers/leds/Makefile

@@ -26,6 +26,7 @@ obj-$(CONFIG_LEDS_LP3944)		+= leds-lp3944.o
 obj-$(CONFIG_LEDS_LP55XX_COMMON)	+= leds-lp55xx-common.o
 obj-$(CONFIG_LEDS_LP5521)		+= leds-lp5521.o
 obj-$(CONFIG_LEDS_LP5523)		+= leds-lp5523.o
+obj-$(CONFIG_LEDS_LP5562)		+= leds-lp5562.o
 obj-$(CONFIG_LEDS_LP8788)		+= leds-lp8788.o
 obj-$(CONFIG_LEDS_TCA6507)		+= leds-tca6507.o
 obj-$(CONFIG_LEDS_CLEVO_MAIL)		+= leds-clevo-mail.o

drivers/leds/leds-lp55xx-common.c

 /*
- * LP5521/LP5523/LP55231 Common Driver
+ * LP5521/LP5523/LP55231/LP5562 Common Driver
  *
  * Copyright 2012 Texas Instruments
  *

include/linux/platform_data/leds-lp55xx.h

@@ -32,6 +32,13 @@
 #define LP5521_CLK_INT			1	/* Internal clock */
 #define LP5521_CLK_AUTO			2	/* Automatic clock selection */
 
+/* Bits in LP5562 CONFIG register */
+#define LP5562_PWM_HF			LP5521_PWM_HF
+#define LP5562_PWRSAVE_EN		LP5521_PWRSAVE_EN
+#define LP5562_CLK_SRC_EXT		LP5521_CLK_SRC_EXT
+#define LP5562_CLK_INT			LP5521_CLK_INT
+#define LP5562_CLK_AUTO			LP5521_CLK_AUTO
+
 struct lp55xx_led_config {
 	const char *name;
 	u8 chan_nr;
@@ -40,9 +47,9 @@ struct lp55xx_led_config {
 };
 
 struct lp55xx_predef_pattern {
-	u8 *r;
-	u8 *g;
-	u8 *b;
+	const u8 *r;
+	const u8 *g;
+	const u8 *b;
 	u8 size_r;
 	u8 size_g;
 	u8 size_b;