backlight: new backlight driver for LP855x devices
THis driver supports TI LP8550/LP8551/LP8552/LP8553/LP8556 backlight
devices.
The brightness can be controlled by the I2C or PWM input. The lp855x
driver provides both modes. For the PWM control, pwm-specific functions
can be defined in the platform data. And some information can be read
via the sysfs(lp855x device attributes).
For details, please refer to Documentation/backlight/lp855x-driver.txt.
[axel.lin@gmail.com: add missing mutex_unlock in lp855x_read_byte() error path]
[axel.lin@gmail.com: check platform data in lp855x_probe()]
[axel.lin@gmail.com: small cleanups]
[dan.carpenter@oracle.com: silence a compiler warning]
[axel.lin@gmail.com: use id->driver_data to differentiate lp855x chips]
[akpm@linux-foundation.org: simplify boolean return expression]
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/lp855x.h b/include/linux/lp855x.h
new file mode 100644
index 0000000..781a490
--- /dev/null
+++ b/include/linux/lp855x.h
@@ -0,0 +1,131 @@
+/*
+ * LP855x Backlight Driver
+ *
+ * Copyright (C) 2011 Texas Instruments
+ *
+ * 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 _LP855X_H
+#define _LP855X_H
+
+#define BL_CTL_SHFT (0)
+#define BRT_MODE_SHFT (1)
+#define BRT_MODE_MASK (0x06)
+
+/* Enable backlight. Only valid when BRT_MODE=10(I2C only) */
+#define ENABLE_BL (1)
+#define DISABLE_BL (0)
+
+#define I2C_CONFIG(id) id ## _I2C_CONFIG
+#define PWM_CONFIG(id) id ## _PWM_CONFIG
+
+/* DEVICE CONTROL register - LP8550 */
+#define LP8550_PWM_CONFIG (LP8550_PWM_ONLY << BRT_MODE_SHFT)
+#define LP8550_I2C_CONFIG ((ENABLE_BL << BL_CTL_SHFT) | \
+ (LP8550_I2C_ONLY << BRT_MODE_SHFT))
+
+/* DEVICE CONTROL register - LP8551 */
+#define LP8551_PWM_CONFIG LP8550_PWM_CONFIG
+#define LP8551_I2C_CONFIG LP8550_I2C_CONFIG
+
+/* DEVICE CONTROL register - LP8552 */
+#define LP8552_PWM_CONFIG LP8550_PWM_CONFIG
+#define LP8552_I2C_CONFIG LP8550_I2C_CONFIG
+
+/* DEVICE CONTROL register - LP8553 */
+#define LP8553_PWM_CONFIG LP8550_PWM_CONFIG
+#define LP8553_I2C_CONFIG LP8550_I2C_CONFIG
+
+/* DEVICE CONTROL register - LP8556 */
+#define LP8556_PWM_CONFIG (LP8556_PWM_ONLY << BRT_MODE_SHFT)
+#define LP8556_COMB1_CONFIG (LP8556_COMBINED1 << BRT_MODE_SHFT)
+#define LP8556_I2C_CONFIG ((ENABLE_BL << BL_CTL_SHFT) | \
+ (LP8556_I2C_ONLY << BRT_MODE_SHFT))
+#define LP8556_COMB2_CONFIG (LP8556_COMBINED2 << BRT_MODE_SHFT)
+
+/* ROM area boundary */
+#define EEPROM_START (0xA0)
+#define EEPROM_END (0xA7)
+#define EPROM_START (0xA0)
+#define EPROM_END (0xAF)
+
+enum lp855x_chip_id {
+ LP8550,
+ LP8551,
+ LP8552,
+ LP8553,
+ LP8556,
+};
+
+enum lp855x_brightness_ctrl_mode {
+ PWM_BASED = 1,
+ REGISTER_BASED,
+};
+
+enum lp8550_brighntess_source {
+ LP8550_PWM_ONLY,
+ LP8550_I2C_ONLY = 2,
+};
+
+enum lp8551_brighntess_source {
+ LP8551_PWM_ONLY = LP8550_PWM_ONLY,
+ LP8551_I2C_ONLY = LP8550_I2C_ONLY,
+};
+
+enum lp8552_brighntess_source {
+ LP8552_PWM_ONLY = LP8550_PWM_ONLY,
+ LP8552_I2C_ONLY = LP8550_I2C_ONLY,
+};
+
+enum lp8553_brighntess_source {
+ LP8553_PWM_ONLY = LP8550_PWM_ONLY,
+ LP8553_I2C_ONLY = LP8550_I2C_ONLY,
+};
+
+enum lp8556_brightness_source {
+ LP8556_PWM_ONLY,
+ LP8556_COMBINED1, /* pwm + i2c before the shaper block */
+ LP8556_I2C_ONLY,
+ LP8556_COMBINED2, /* pwm + i2c after the shaper block */
+};
+
+struct lp855x_pwm_data {
+ void (*pwm_set_intensity) (int brightness, int max_brightness);
+ int (*pwm_get_intensity) (int max_brightness);
+};
+
+struct lp855x_rom_data {
+ u8 addr;
+ u8 val;
+};
+
+/**
+ * struct lp855x_platform_data
+ * @name : Backlight driver name. If it is not defined, default name is set.
+ * @mode : brightness control by pwm or lp855x register
+ * @device_control : value of DEVICE CONTROL register
+ * @initial_brightness : initial value of backlight brightness
+ * @pwm_data : platform specific pwm generation functions.
+ Only valid when mode is PWM_BASED.
+ * @load_new_rom_data :
+ 0 : use default configuration data
+ 1 : update values of eeprom or eprom registers on loading driver
+ * @size_program : total size of lp855x_rom_data
+ * @rom_data : list of new eeprom/eprom registers
+ */
+struct lp855x_platform_data {
+ char *name;
+ enum lp855x_brightness_ctrl_mode mode;
+ u8 device_control;
+ int initial_brightness;
+ struct lp855x_pwm_data pwm_data;
+ u8 load_new_rom_data;
+ int size_program;
+ struct lp855x_rom_data *rom_data;
+};
+
+#endif