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Diffstat (limited to 'drivers/video/backlight/lm3630a_bl.c')
-rw-r--r--drivers/video/backlight/lm3630a_bl.c630
1 files changed, 630 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..475f35635
--- /dev/null
+++ b/drivers/video/backlight/lm3630a_bl.c
@@ -0,0 +1,630 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+* Simple driver for Texas Instruments LM3630A Backlight driver chip
+* Copyright (C) 2012 Texas Instruments
+*/
+#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/gpio/consumer.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
+
+#define LM3630A_BANK_0 0
+#define LM3630A_BANK_1 1
+
+#define LM3630A_NUM_SINKS 2
+#define LM3630A_SINK_0 0
+#define LM3630A_SINK_1 1
+
+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 gpio_desc *enable_gpio;
+ struct regmap *regmap;
+ struct pwm_device *pwmd;
+ struct pwm_state pwmd_state;
+};
+
+/* 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, &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 int lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
+{
+ int err;
+
+ pchip->pwmd_state.period = pchip->pdata->pwm_period;
+
+ err = pwm_set_relative_duty_cycle(&pchip->pwmd_state, br, br_max);
+ if (err)
+ return err;
+
+ pchip->pwmd_state.enabled = pchip->pwmd_state.duty_cycle ? true : false;
+
+ return pwm_apply_state(pchip->pwmd, &pchip->pwmd_state);
+}
+
+/* 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)
+ return lm3630a_pwm_ctrl(pchip, bl->props.brightness,
+ bl->props.max_brightness);
+
+ /* 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)
+ return lm3630a_pwm_ctrl(pchip, bl->props.brightness,
+ bl->props.max_brightness);
+
+ /* 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 lm3630a_platform_data *pdata = pchip->pdata;
+ struct backlight_properties props;
+ const char *label;
+
+ props.type = BACKLIGHT_RAW;
+ if (pdata->leda_ctrl != LM3630A_LEDA_DISABLE) {
+ props.brightness = pdata->leda_init_brt;
+ props.max_brightness = pdata->leda_max_brt;
+ label = pdata->leda_label ? pdata->leda_label : "lm3630a_leda";
+ pchip->bleda =
+ devm_backlight_device_register(pchip->dev, label,
+ 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;
+ label = pdata->ledb_label ? pdata->ledb_label : "lm3630a_ledb";
+ pchip->bledb =
+ devm_backlight_device_register(pchip->dev, label,
+ 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_parse_led_sources(struct fwnode_handle *node,
+ int default_led_sources)
+{
+ u32 sources[LM3630A_NUM_SINKS];
+ int ret, num_sources, i;
+
+ num_sources = fwnode_property_count_u32(node, "led-sources");
+ if (num_sources < 0)
+ return default_led_sources;
+ else if (num_sources > ARRAY_SIZE(sources))
+ return -EINVAL;
+
+ ret = fwnode_property_read_u32_array(node, "led-sources", sources,
+ num_sources);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < num_sources; i++) {
+ if (sources[i] != LM3630A_SINK_0 && sources[i] != LM3630A_SINK_1)
+ return -EINVAL;
+
+ ret |= BIT(sources[i]);
+ }
+
+ return ret;
+}
+
+static int lm3630a_parse_bank(struct lm3630a_platform_data *pdata,
+ struct fwnode_handle *node, int *seen_led_sources)
+{
+ int led_sources, ret;
+ const char *label;
+ u32 bank, val;
+ bool linear;
+
+ ret = fwnode_property_read_u32(node, "reg", &bank);
+ if (ret)
+ return ret;
+
+ if (bank != LM3630A_BANK_0 && bank != LM3630A_BANK_1)
+ return -EINVAL;
+
+ led_sources = lm3630a_parse_led_sources(node, BIT(bank));
+ if (led_sources < 0)
+ return led_sources;
+
+ if (*seen_led_sources & led_sources)
+ return -EINVAL;
+
+ *seen_led_sources |= led_sources;
+
+ linear = fwnode_property_read_bool(node,
+ "ti,linear-mapping-mode");
+ if (bank) {
+ if (led_sources & BIT(LM3630A_SINK_0) ||
+ !(led_sources & BIT(LM3630A_SINK_1)))
+ return -EINVAL;
+
+ pdata->ledb_ctrl = linear ?
+ LM3630A_LEDB_ENABLE_LINEAR :
+ LM3630A_LEDB_ENABLE;
+ } else {
+ if (!(led_sources & BIT(LM3630A_SINK_0)))
+ return -EINVAL;
+
+ pdata->leda_ctrl = linear ?
+ LM3630A_LEDA_ENABLE_LINEAR :
+ LM3630A_LEDA_ENABLE;
+
+ if (led_sources & BIT(LM3630A_SINK_1))
+ pdata->ledb_ctrl = LM3630A_LEDB_ON_A;
+ }
+
+ ret = fwnode_property_read_string(node, "label", &label);
+ if (!ret) {
+ if (bank)
+ pdata->ledb_label = label;
+ else
+ pdata->leda_label = label;
+ }
+
+ ret = fwnode_property_read_u32(node, "default-brightness",
+ &val);
+ if (!ret) {
+ if (bank)
+ pdata->ledb_init_brt = val;
+ else
+ pdata->leda_init_brt = val;
+ }
+
+ ret = fwnode_property_read_u32(node, "max-brightness", &val);
+ if (!ret) {
+ if (bank)
+ pdata->ledb_max_brt = val;
+ else
+ pdata->leda_max_brt = val;
+ }
+
+ return 0;
+}
+
+static int lm3630a_parse_node(struct lm3630a_chip *pchip,
+ struct lm3630a_platform_data *pdata)
+{
+ int ret = -ENODEV, seen_led_sources = 0;
+ struct fwnode_handle *node;
+
+ device_for_each_child_node(pchip->dev, node) {
+ ret = lm3630a_parse_bank(pdata, node, &seen_led_sources);
+ if (ret) {
+ fwnode_handle_put(node);
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+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_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;
+
+ rval = lm3630a_parse_node(pchip, pdata);
+ if (rval) {
+ dev_err(&client->dev, "fail : parse node\n");
+ return rval;
+ }
+ }
+ pchip->pdata = pdata;
+
+ pchip->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(pchip->enable_gpio)) {
+ rval = PTR_ERR(pchip->enable_gpio);
+ return rval;
+ }
+
+ /* 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);
+ }
+
+ pwm_init_state(pchip->pwmd, &pchip->pwmd_state);
+ }
+
+ /* 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 void 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);
+ destroy_workqueue(pchip->irqthread);
+ }
+}
+
+static const struct i2c_device_id lm3630a_id[] = {
+ {LM3630A_NAME, 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, lm3630a_id);
+
+static const struct of_device_id lm3630a_match_table[] = {
+ { .compatible = "ti,lm3630a", },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, lm3630a_match_table);
+
+static struct i2c_driver lm3630a_i2c_driver = {
+ .driver = {
+ .name = LM3630A_NAME,
+ .of_match_table = lm3630a_match_table,
+ },
+ .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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 06:01:18 +0000