diff options
Diffstat (limited to 'drivers/video/backlight/lm3630a_bl.c')
| -rw-r--r-- | drivers/video/backlight/lm3630a_bl.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/video/backlight/lm3630a_bl.c b/drivers/video/backlight/lm3630a_bl.c new file mode 100644 index 000000000..f17e5a886 --- /dev/null +++ b/drivers/video/backlight/lm3630a_bl.c @@ -0,0 +1,489 @@ +/* +* Simple driver for Texas Instruments LM3630A Backlight 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/backlight.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/uaccess.h> +#include <linux/interrupt.h> +#include <linux/regmap.h> +#include <linux/pwm.h> +#include <linux/platform_data/lm3630a_bl.h> + +#define REG_CTRL 0x00 +#define REG_BOOST 0x02 +#define REG_CONFIG 0x01 +#define REG_BRT_A 0x03 +#define REG_BRT_B 0x04 +#define REG_I_A 0x05 +#define REG_I_B 0x06 +#define REG_INT_STATUS 0x09 +#define REG_INT_EN 0x0A +#define REG_FAULT 0x0B +#define REG_PWM_OUTLOW 0x12 +#define REG_PWM_OUTHIGH 0x13 +#define REG_FILTER_STRENGTH 0x50 +#define REG_MAX 0x50 + +#define INT_DEBOUNCE_MSEC 10 +struct lm3630a_chip { + struct device *dev; + struct delayed_work work; + + int irq; + struct workqueue_struct *irqthread; + struct lm3630a_platform_data *pdata; + struct backlight_device *bleda; + struct backlight_device *bledb; + struct regmap *regmap; + struct pwm_device *pwmd; +}; + +/* i2c access */ +static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg) +{ + int rval; + unsigned int reg_val; + + rval = regmap_read(pchip->regmap, reg, ®_val); + if (rval < 0) + return rval; + return reg_val & 0xFF; +} + +static int lm3630a_write(struct lm3630a_chip *pchip, + unsigned int reg, unsigned int data) +{ + return regmap_write(pchip->regmap, reg, data); +} + +static int lm3630a_update(struct lm3630a_chip *pchip, + unsigned int reg, unsigned int mask, + unsigned int data) +{ + return regmap_update_bits(pchip->regmap, reg, mask, data); +} + +/* initialize chip */ +static int lm3630a_chip_init(struct lm3630a_chip *pchip) +{ + int rval; + struct lm3630a_platform_data *pdata = pchip->pdata; + + usleep_range(1000, 2000); + /* set Filter Strength Register */ + rval = lm3630a_write(pchip, REG_FILTER_STRENGTH, 0x03); + /* set Cofig. register */ + rval |= lm3630a_update(pchip, REG_CONFIG, 0x07, pdata->pwm_ctrl); + /* set boost control */ + rval |= lm3630a_write(pchip, REG_BOOST, 0x38); + /* set current A */ + rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F); + /* set current B */ + rval |= lm3630a_write(pchip, REG_I_B, 0x1F); + /* set control */ + rval |= lm3630a_update(pchip, REG_CTRL, 0x14, pdata->leda_ctrl); + rval |= lm3630a_update(pchip, REG_CTRL, 0x0B, pdata->ledb_ctrl); + usleep_range(1000, 2000); + /* set brightness A and B */ + rval |= lm3630a_write(pchip, REG_BRT_A, pdata->leda_init_brt); + rval |= lm3630a_write(pchip, REG_BRT_B, pdata->ledb_init_brt); + + if (rval < 0) + dev_err(pchip->dev, "i2c failed to access register\n"); + return rval; +} + +/* interrupt handling */ +static void lm3630a_delayed_func(struct work_struct *work) +{ + int rval; + struct lm3630a_chip *pchip; + + pchip = container_of(work, struct lm3630a_chip, work.work); + + rval = lm3630a_read(pchip, REG_INT_STATUS); + if (rval < 0) { + dev_err(pchip->dev, + "i2c failed to access REG_INT_STATUS Register\n"); + return; + } + + dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval); +} + +static irqreturn_t lm3630a_isr_func(int irq, void *chip) +{ + int rval; + struct lm3630a_chip *pchip = chip; + unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC); + + queue_delayed_work(pchip->irqthread, &pchip->work, delay); + + rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00); + if (rval < 0) { + dev_err(pchip->dev, "i2c failed to access register\n"); + return IRQ_NONE; + } + return IRQ_HANDLED; +} + +static int lm3630a_intr_config(struct lm3630a_chip *pchip) +{ + int rval; + + rval = lm3630a_write(pchip, REG_INT_EN, 0x87); + if (rval < 0) + return rval; + + INIT_DELAYED_WORK(&pchip->work, lm3630a_delayed_func); + pchip->irqthread = create_singlethread_workqueue("lm3630a-irqthd"); + if (!pchip->irqthread) { + dev_err(pchip->dev, "create irq thread fail\n"); + return -ENOMEM; + } + if (request_threaded_irq + (pchip->irq, NULL, lm3630a_isr_func, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "lm3630a_irq", pchip)) { + dev_err(pchip->dev, "request threaded irq fail\n"); + destroy_workqueue(pchip->irqthread); + return -ENOMEM; + } + return rval; +} + +static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max) +{ + unsigned int period = pchip->pdata->pwm_period; + unsigned int duty = br * period / br_max; + + pwm_config(pchip->pwmd, duty, period); + if (duty) + pwm_enable(pchip->pwmd); + else + pwm_disable(pchip->pwmd); +} + +/* update and get brightness */ +static int lm3630a_bank_a_update_status(struct backlight_device *bl) +{ + int ret; + struct lm3630a_chip *pchip = bl_get_data(bl); + enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl; + + /* pwm control */ + if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) { + lm3630a_pwm_ctrl(pchip, bl->props.brightness, + bl->props.max_brightness); + return 0; + } + + /* disable sleep */ + ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00); + if (ret < 0) + goto out_i2c_err; + usleep_range(1000, 2000); + /* minimum brightness is 0x04 */ + ret = lm3630a_write(pchip, REG_BRT_A, bl->props.brightness); + if (bl->props.brightness < 0x4) + ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDA_ENABLE, 0); + else + ret |= lm3630a_update(pchip, REG_CTRL, + LM3630A_LEDA_ENABLE, LM3630A_LEDA_ENABLE); + if (ret < 0) + goto out_i2c_err; + return 0; + +out_i2c_err: + dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret)); + return ret; +} + +static int lm3630a_bank_a_get_brightness(struct backlight_device *bl) +{ + int brightness, rval; + struct lm3630a_chip *pchip = bl_get_data(bl); + enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl; + + if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) { + rval = lm3630a_read(pchip, REG_PWM_OUTHIGH); + if (rval < 0) + goto out_i2c_err; + brightness = (rval & 0x01) << 8; + rval = lm3630a_read(pchip, REG_PWM_OUTLOW); + if (rval < 0) + goto out_i2c_err; + brightness |= rval; + goto out; + } + + /* disable sleep */ + rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00); + if (rval < 0) + goto out_i2c_err; + usleep_range(1000, 2000); + rval = lm3630a_read(pchip, REG_BRT_A); + if (rval < 0) + goto out_i2c_err; + brightness = rval; + +out: + bl->props.brightness = brightness; + return bl->props.brightness; +out_i2c_err: + dev_err(pchip->dev, "i2c failed to access register\n"); + return 0; +} + +static const struct backlight_ops lm3630a_bank_a_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = lm3630a_bank_a_update_status, + .get_brightness = lm3630a_bank_a_get_brightness, +}; + +/* update and get brightness */ +static int lm3630a_bank_b_update_status(struct backlight_device *bl) +{ + int ret; + struct lm3630a_chip *pchip = bl_get_data(bl); + enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl; + + /* pwm control */ + if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) { + lm3630a_pwm_ctrl(pchip, bl->props.brightness, + bl->props.max_brightness); + return 0; + } + + /* disable sleep */ + ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00); + if (ret < 0) + goto out_i2c_err; + usleep_range(1000, 2000); + /* minimum brightness is 0x04 */ + ret = lm3630a_write(pchip, REG_BRT_B, bl->props.brightness); + if (bl->props.brightness < 0x4) + ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDB_ENABLE, 0); + else + ret |= lm3630a_update(pchip, REG_CTRL, + LM3630A_LEDB_ENABLE, LM3630A_LEDB_ENABLE); + if (ret < 0) + goto out_i2c_err; + return 0; + +out_i2c_err: + dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret)); + return ret; +} + +static int lm3630a_bank_b_get_brightness(struct backlight_device *bl) +{ + int brightness, rval; + struct lm3630a_chip *pchip = bl_get_data(bl); + enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl; + + if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) { + rval = lm3630a_read(pchip, REG_PWM_OUTHIGH); + if (rval < 0) + goto out_i2c_err; + brightness = (rval & 0x01) << 8; + rval = lm3630a_read(pchip, REG_PWM_OUTLOW); + if (rval < 0) + goto out_i2c_err; + brightness |= rval; + goto out; + } + + /* disable sleep */ + rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00); + if (rval < 0) + goto out_i2c_err; + usleep_range(1000, 2000); + rval = lm3630a_read(pchip, REG_BRT_B); + if (rval < 0) + goto out_i2c_err; + brightness = rval; + +out: + bl->props.brightness = brightness; + return bl->props.brightness; +out_i2c_err: + dev_err(pchip->dev, "i2c failed to access register\n"); + return 0; +} + +static const struct backlight_ops lm3630a_bank_b_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = lm3630a_bank_b_update_status, + .get_brightness = lm3630a_bank_b_get_brightness, +}; + +static int lm3630a_backlight_register(struct lm3630a_chip *pchip) +{ + struct backlight_properties props; + struct lm3630a_platform_data *pdata = pchip->pdata; + + props.type = BACKLIGHT_RAW; + if (pdata->leda_ctrl != LM3630A_LEDA_DISABLE) { + props.brightness = pdata->leda_init_brt; + props.max_brightness = pdata->leda_max_brt; + pchip->bleda = + devm_backlight_device_register(pchip->dev, "lm3630a_leda", + pchip->dev, pchip, + &lm3630a_bank_a_ops, &props); + if (IS_ERR(pchip->bleda)) + return PTR_ERR(pchip->bleda); + } + + if ((pdata->ledb_ctrl != LM3630A_LEDB_DISABLE) && + (pdata->ledb_ctrl != LM3630A_LEDB_ON_A)) { + props.brightness = pdata->ledb_init_brt; + props.max_brightness = pdata->ledb_max_brt; + pchip->bledb = + devm_backlight_device_register(pchip->dev, "lm3630a_ledb", + pchip->dev, pchip, + &lm3630a_bank_b_ops, &props); + if (IS_ERR(pchip->bledb)) + return PTR_ERR(pchip->bledb); + } + return 0; +} + +static const struct regmap_config lm3630a_regmap = { + .reg_bits = 8, + .val_bits = 8, + .max_register = REG_MAX, +}; + +static int lm3630a_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct lm3630a_platform_data *pdata = dev_get_platdata(&client->dev); + struct lm3630a_chip *pchip; + int rval; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "fail : i2c functionality check\n"); + return -EOPNOTSUPP; + } + + pchip = devm_kzalloc(&client->dev, sizeof(struct lm3630a_chip), + GFP_KERNEL); + if (!pchip) + return -ENOMEM; + pchip->dev = &client->dev; + + pchip->regmap = devm_regmap_init_i2c(client, &lm3630a_regmap); + if (IS_ERR(pchip->regmap)) { + rval = PTR_ERR(pchip->regmap); + dev_err(&client->dev, "fail : allocate reg. map: %d\n", rval); + return rval; + } + + i2c_set_clientdata(client, pchip); + if (pdata == NULL) { + pdata = devm_kzalloc(pchip->dev, + sizeof(struct lm3630a_platform_data), + GFP_KERNEL); + if (pdata == NULL) + return -ENOMEM; + /* default values */ + pdata->leda_ctrl = LM3630A_LEDA_ENABLE; + pdata->ledb_ctrl = LM3630A_LEDB_ENABLE; + pdata->leda_max_brt = LM3630A_MAX_BRIGHTNESS; + pdata->ledb_max_brt = LM3630A_MAX_BRIGHTNESS; + pdata->leda_init_brt = LM3630A_MAX_BRIGHTNESS; + pdata->ledb_init_brt = LM3630A_MAX_BRIGHTNESS; + } + pchip->pdata = pdata; + + /* chip initialize */ + rval = lm3630a_chip_init(pchip); + if (rval < 0) { + dev_err(&client->dev, "fail : init chip\n"); + return rval; + } + /* backlight register */ + rval = lm3630a_backlight_register(pchip); + if (rval < 0) { + dev_err(&client->dev, "fail : backlight register.\n"); + return rval; + } + /* pwm */ + if (pdata->pwm_ctrl != LM3630A_PWM_DISABLE) { + pchip->pwmd = devm_pwm_get(pchip->dev, "lm3630a-pwm"); + if (IS_ERR(pchip->pwmd)) { + dev_err(&client->dev, "fail : get pwm device\n"); + return PTR_ERR(pchip->pwmd); + } + + /* + * FIXME: pwm_apply_args() should be removed when switching to + * the atomic PWM API. + */ + pwm_apply_args(pchip->pwmd); + } + + /* interrupt enable : irq 0 is not allowed */ + pchip->irq = client->irq; + if (pchip->irq) { + rval = lm3630a_intr_config(pchip); + if (rval < 0) + return rval; + } + dev_info(&client->dev, "LM3630A backlight register OK.\n"); + return 0; +} + +static int lm3630a_remove(struct i2c_client *client) +{ + int rval; + struct lm3630a_chip *pchip = i2c_get_clientdata(client); + + rval = lm3630a_write(pchip, REG_BRT_A, 0); + if (rval < 0) + dev_err(pchip->dev, "i2c failed to access register\n"); + + rval = lm3630a_write(pchip, REG_BRT_B, 0); + if (rval < 0) + dev_err(pchip->dev, "i2c failed to access register\n"); + + if (pchip->irq) { + free_irq(pchip->irq, pchip); + flush_workqueue(pchip->irqthread); + destroy_workqueue(pchip->irqthread); + } + return 0; +} + +static const struct i2c_device_id lm3630a_id[] = { + {LM3630A_NAME, 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, lm3630a_id); + +static struct i2c_driver lm3630a_i2c_driver = { + .driver = { + .name = LM3630A_NAME, + }, + .probe = lm3630a_probe, + .remove = lm3630a_remove, + .id_table = lm3630a_id, +}; + +module_i2c_driver(lm3630a_i2c_driver); + +MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A"); +MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>"); +MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>"); +MODULE_LICENSE("GPL v2"); |