backlight: add new lm3639 backlight driver
This driver is a general version for LM3639 backlgiht + flash driver chip
of TI.
LM3639:
The LM3639 is a single chip LCD Display Backlight driver + white LED
Camera driver. Programming is done over an I2C compatible interface.
www.ti.com
[akpm@linux-foundation.org: code layout tweaks]
Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Daniel Jeong <daniel.jeong@ti.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/backlight/lm3639_bl.c b/drivers/video/backlight/lm3639_bl.c
new file mode 100644
index 0000000..c6915c6
--- /dev/null
+++ b/drivers/video/backlight/lm3639_bl.c
@@ -0,0 +1,437 @@
+/*
+* Simple driver for Texas Instruments LM3639 Backlight + Flash LED driver chip
+* Copyright (C) 2012 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.
+*
+*/
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/interrupt.h>
+#include <linux/regmap.h>
+#include <linux/platform_data/lm3639_bl.h>
+
+#define REG_DEV_ID 0x00
+#define REG_CHECKSUM 0x01
+#define REG_BL_CONF_1 0x02
+#define REG_BL_CONF_2 0x03
+#define REG_BL_CONF_3 0x04
+#define REG_BL_CONF_4 0x05
+#define REG_FL_CONF_1 0x06
+#define REG_FL_CONF_2 0x07
+#define REG_FL_CONF_3 0x08
+#define REG_IO_CTRL 0x09
+#define REG_ENABLE 0x0A
+#define REG_FLAG 0x0B
+#define REG_MAX REG_FLAG
+
+struct lm3639_chip_data {
+ struct device *dev;
+ struct lm3639_platform_data *pdata;
+
+ struct backlight_device *bled;
+ struct led_classdev cdev_flash;
+ struct led_classdev cdev_torch;
+ struct regmap *regmap;
+
+ unsigned int bled_mode;
+ unsigned int bled_map;
+ unsigned int last_flag;
+};
+
+/* initialize chip */
+static int __devinit lm3639_chip_init(struct lm3639_chip_data *pchip)
+{
+ int ret;
+ unsigned int reg_val;
+ struct lm3639_platform_data *pdata = pchip->pdata;
+
+ /* input pins config. */
+ ret =
+ regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x08,
+ pdata->pin_pwm);
+ if (ret < 0)
+ goto out;
+
+ reg_val = (pdata->pin_pwm & 0x40) | pdata->pin_strobe | pdata->pin_tx;
+ ret = regmap_update_bits(pchip->regmap, REG_IO_CTRL, 0x7C, reg_val);
+ if (ret < 0)
+ goto out;
+
+ /* init brightness */
+ ret = regmap_write(pchip->regmap, REG_BL_CONF_4, pdata->init_brt_led);
+ if (ret < 0)
+ goto out;
+
+ ret = regmap_write(pchip->regmap, REG_BL_CONF_3, pdata->init_brt_led);
+ if (ret < 0)
+ goto out;
+
+ /* output pins config. */
+ if (!pdata->init_brt_led)
+ reg_val = pdata->fled_pins | pdata->bled_pins;
+ else
+ reg_val = pdata->fled_pins | pdata->bled_pins | 0x01;
+
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x79, reg_val);
+ if (ret < 0)
+ goto out;
+
+ return ret;
+out:
+ dev_err(pchip->dev, "i2c failed to access register\n");
+ return ret;
+}
+
+/* update and get brightness */
+static int lm3639_bled_update_status(struct backlight_device *bl)
+{
+ int ret;
+ unsigned int reg_val;
+ struct lm3639_chip_data *pchip = bl_get_data(bl);
+ struct lm3639_platform_data *pdata = pchip->pdata;
+
+ ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
+ if (ret < 0)
+ goto out;
+
+ if (reg_val != 0)
+ dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
+
+ /* pwm control */
+ if (pdata->pin_pwm) {
+ if (pdata->pwm_set_intensity)
+ pdata->pwm_set_intensity(bl->props.brightness,
+ pdata->max_brt_led);
+ else
+ dev_err(pchip->dev,
+ "No pwm control func. in plat-data\n");
+ return bl->props.brightness;
+ }
+
+ /* i2c control and set brigtness */
+ ret = regmap_write(pchip->regmap, REG_BL_CONF_4, bl->props.brightness);
+ if (ret < 0)
+ goto out;
+ ret = regmap_write(pchip->regmap, REG_BL_CONF_3, bl->props.brightness);
+ if (ret < 0)
+ goto out;
+
+ if (!bl->props.brightness)
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x00);
+ else
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x01);
+ if (ret < 0)
+ goto out;
+
+ return bl->props.brightness;
+out:
+ dev_err(pchip->dev, "i2c failed to access registers\n");
+ return bl->props.brightness;
+}
+
+static int lm3639_bled_get_brightness(struct backlight_device *bl)
+{
+ int ret;
+ unsigned int reg_val;
+ struct lm3639_chip_data *pchip = bl_get_data(bl);
+ struct lm3639_platform_data *pdata = pchip->pdata;
+
+ if (pdata->pin_pwm) {
+ if (pdata->pwm_get_intensity)
+ bl->props.brightness = pdata->pwm_get_intensity();
+ else
+ dev_err(pchip->dev,
+ "No pwm control func. in plat-data\n");
+ return bl->props.brightness;
+ }
+
+ ret = regmap_read(pchip->regmap, REG_BL_CONF_1, ®_val);
+ if (ret < 0)
+ goto out;
+ if (reg_val & 0x10)
+ ret = regmap_read(pchip->regmap, REG_BL_CONF_4, ®_val);
+ else
+ ret = regmap_read(pchip->regmap, REG_BL_CONF_3, ®_val);
+ if (ret < 0)
+ goto out;
+ bl->props.brightness = reg_val;
+
+ return bl->props.brightness;
+out:
+ dev_err(pchip->dev, "i2c failed to access register\n");
+ return bl->props.brightness;
+}
+
+static const struct backlight_ops lm3639_bled_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = lm3639_bled_update_status,
+ .get_brightness = lm3639_bled_get_brightness,
+};
+
+/* backlight mapping mode */
+static ssize_t lm3639_bled_mode_store(struct device *dev,
+ struct device_attribute *devAttr,
+ const char *buf, size_t size)
+{
+ ssize_t ret;
+ struct lm3639_chip_data *pchip = dev_get_drvdata(dev);
+ unsigned int state;
+
+ ret = kstrtouint(buf, 10, &state);
+ if (ret)
+ goto out_input;
+
+ if (!state)
+ ret =
+ regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
+ 0x00);
+ else
+ ret =
+ regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
+ 0x10);
+
+ if (ret < 0)
+ goto out;
+
+ return size;
+
+out:
+ dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
+ return size;
+
+out_input:
+ dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
+ return size;
+
+}
+
+static DEVICE_ATTR(bled_mode, 0666, NULL, lm3639_bled_mode_store);
+
+/* torch */
+static void lm3639_torch_brightness_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ int ret;
+ unsigned int reg_val;
+ struct lm3639_chip_data *pchip;
+
+ pchip = container_of(cdev, struct lm3639_chip_data, cdev_torch);
+
+ ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
+ if (ret < 0)
+ goto out;
+ if (reg_val != 0)
+ dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
+
+ /* brightness 0 means off state */
+ if (!brightness) {
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
+ if (ret < 0)
+ goto out;
+ return;
+ }
+
+ ret = regmap_update_bits(pchip->regmap,
+ REG_FL_CONF_1, 0x70, (brightness - 1) << 4);
+ if (ret < 0)
+ goto out;
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x02);
+ if (ret < 0)
+ goto out;
+
+ return;
+out:
+ dev_err(pchip->dev, "i2c failed to access register\n");
+ return;
+}
+
+/* flash */
+static void lm3639_flash_brightness_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ int ret;
+ unsigned int reg_val;
+ struct lm3639_chip_data *pchip;
+
+ pchip = container_of(cdev, struct lm3639_chip_data, cdev_flash);
+
+ ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
+ if (ret < 0)
+ goto out;
+ if (reg_val != 0)
+ dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
+
+ /* torch off before flash control */
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
+ if (ret < 0)
+ goto out;
+
+ /* brightness 0 means off state */
+ if (!brightness)
+ return;
+
+ ret = regmap_update_bits(pchip->regmap,
+ REG_FL_CONF_1, 0x0F, brightness - 1);
+ if (ret < 0)
+ goto out;
+ ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x06);
+ if (ret < 0)
+ goto out;
+
+ return;
+out:
+ dev_err(pchip->dev, "i2c failed to access register\n");
+ return;
+}
+
+static const struct regmap_config lm3639_regmap = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = REG_MAX,
+};
+
+static int __devinit lm3639_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct lm3639_chip_data *pchip;
+ struct lm3639_platform_data *pdata = client->dev.platform_data;
+ struct backlight_properties props;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(&client->dev, "i2c functionality check fail.\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (pdata == NULL) {
+ dev_err(&client->dev, "Needs Platform Data.\n");
+ return -ENODATA;
+ }
+
+ pchip = devm_kzalloc(&client->dev,
+ sizeof(struct lm3639_chip_data), GFP_KERNEL);
+ if (!pchip)
+ return -ENOMEM;
+
+ pchip->pdata = pdata;
+ pchip->dev = &client->dev;
+
+ pchip->regmap = devm_regmap_init_i2c(client, &lm3639_regmap);
+ if (IS_ERR(pchip->regmap)) {
+ ret = PTR_ERR(pchip->regmap);
+ dev_err(&client->dev, "fail : allocate register map: %d\n",
+ ret);
+ return ret;
+ }
+ i2c_set_clientdata(client, pchip);
+
+ /* chip initialize */
+ ret = lm3639_chip_init(pchip);
+ if (ret < 0) {
+ dev_err(&client->dev, "fail : chip init\n");
+ goto err_out;
+ }
+
+ /* backlight */
+ props.type = BACKLIGHT_RAW;
+ props.brightness = pdata->init_brt_led;
+ props.max_brightness = pdata->max_brt_led;
+ pchip->bled =
+ backlight_device_register("lm3639_bled", pchip->dev, pchip,
+ &lm3639_bled_ops, &props);
+ if (IS_ERR(pchip->bled)) {
+ dev_err(&client->dev, "fail : backlight register\n");
+ ret = -EIO;
+ goto err_out;
+ }
+
+ ret = device_create_file(&(pchip->bled->dev), &dev_attr_bled_mode);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed : add sysfs entries\n");
+ ret = -EIO;
+ goto err_bled_mode;
+ }
+
+ /* flash */
+ pchip->cdev_flash.name = "lm3639_flash";
+ pchip->cdev_flash.max_brightness = 16;
+ pchip->cdev_flash.brightness_set = lm3639_flash_brightness_set;
+ ret = led_classdev_register((struct device *)
+ &client->dev, &pchip->cdev_flash);
+ if (ret < 0) {
+ dev_err(&client->dev, "fail : flash register\n");
+ ret = -EIO;
+ goto err_flash;
+ }
+
+ /* torch */
+ pchip->cdev_torch.name = "lm3639_torch";
+ pchip->cdev_torch.max_brightness = 8;
+ pchip->cdev_torch.brightness_set = lm3639_torch_brightness_set;
+ ret = led_classdev_register((struct device *)
+ &client->dev, &pchip->cdev_torch);
+ if (ret < 0) {
+ dev_err(&client->dev, "fail : torch register\n");
+ ret = -EIO;
+ goto err_torch;
+ }
+
+ return 0;
+
+err_torch:
+ led_classdev_unregister(&pchip->cdev_flash);
+err_flash:
+ device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
+err_bled_mode:
+ backlight_device_unregister(pchip->bled);
+err_out:
+ return ret;
+}
+
+static int __devexit lm3639_remove(struct i2c_client *client)
+{
+ struct lm3639_chip_data *pchip = i2c_get_clientdata(client);
+
+ regmap_write(pchip->regmap, REG_ENABLE, 0x00);
+
+ if (&pchip->cdev_torch)
+ led_classdev_unregister(&pchip->cdev_torch);
+ if (&pchip->cdev_flash)
+ led_classdev_unregister(&pchip->cdev_flash);
+ if (pchip->bled) {
+ device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
+ backlight_device_unregister(pchip->bled);
+ }
+ return 0;
+}
+
+static const struct i2c_device_id lm3639_id[] = {
+ {LM3639_NAME, 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, lm3639_id);
+static struct i2c_driver lm3639_i2c_driver = {
+ .driver = {
+ .name = LM3639_NAME,
+ },
+ .probe = lm3639_probe,
+ .remove = __devexit_p(lm3639_remove),
+ .id_table = lm3639_id,
+};
+
+module_i2c_driver(lm3639_i2c_driver);
+
+MODULE_DESCRIPTION("Texas Instruments Backlight+Flash LED driver for LM3639");
+MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
+MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
+MODULE_LICENSE("GPL v2");