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Diffstat (limited to 'drivers/leds/leds-lm3692x.c')
-rw-r--r--drivers/leds/leds-lm3692x.c529
1 files changed, 529 insertions, 0 deletions
diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c
new file mode 100644
index 0000000000..f8ad61e47a
--- /dev/null
+++ b/drivers/leds/leds-lm3692x.c
@@ -0,0 +1,529 @@
+// SPDX-License-Identifier: GPL-2.0
+// TI LM3692x LED chip family driver
+// Copyright (C) 2017-18 Texas Instruments Incorporated - https://www.ti.com/
+
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/log2.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#define LM36922_MODEL 0
+#define LM36923_MODEL 1
+
+#define LM3692X_REV 0x0
+#define LM3692X_RESET 0x1
+#define LM3692X_EN 0x10
+#define LM3692X_BRT_CTRL 0x11
+#define LM3692X_PWM_CTRL 0x12
+#define LM3692X_BOOST_CTRL 0x13
+#define LM3692X_AUTO_FREQ_HI 0x15
+#define LM3692X_AUTO_FREQ_LO 0x16
+#define LM3692X_BL_ADJ_THRESH 0x17
+#define LM3692X_BRT_LSB 0x18
+#define LM3692X_BRT_MSB 0x19
+#define LM3692X_FAULT_CTRL 0x1e
+#define LM3692X_FAULT_FLAGS 0x1f
+
+#define LM3692X_SW_RESET BIT(0)
+#define LM3692X_DEVICE_EN BIT(0)
+#define LM3692X_LED1_EN BIT(1)
+#define LM3692X_LED2_EN BIT(2)
+#define LM36923_LED3_EN BIT(3)
+#define LM3692X_ENABLE_MASK (LM3692X_DEVICE_EN | LM3692X_LED1_EN | \
+ LM3692X_LED2_EN | LM36923_LED3_EN)
+
+/* Brightness Control Bits */
+#define LM3692X_BL_ADJ_POL BIT(0)
+#define LM3692X_RAMP_RATE_125us 0x00
+#define LM3692X_RAMP_RATE_250us BIT(1)
+#define LM3692X_RAMP_RATE_500us BIT(2)
+#define LM3692X_RAMP_RATE_1ms (BIT(1) | BIT(2))
+#define LM3692X_RAMP_RATE_2ms BIT(3)
+#define LM3692X_RAMP_RATE_4ms (BIT(3) | BIT(1))
+#define LM3692X_RAMP_RATE_8ms (BIT(2) | BIT(3))
+#define LM3692X_RAMP_RATE_16ms (BIT(1) | BIT(2) | BIT(3))
+#define LM3692X_RAMP_EN BIT(4)
+#define LM3692X_BRHT_MODE_REG 0x00
+#define LM3692X_BRHT_MODE_PWM BIT(5)
+#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
+#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6))
+#define LM3692X_MAP_MODE_EXP BIT(7)
+
+/* PWM Register Bits */
+#define LM3692X_PWM_FILTER_100 BIT(0)
+#define LM3692X_PWM_FILTER_150 BIT(1)
+#define LM3692X_PWM_FILTER_200 (BIT(0) | BIT(1))
+#define LM3692X_PWM_HYSTER_1LSB BIT(2)
+#define LM3692X_PWM_HYSTER_2LSB BIT(3)
+#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2))
+#define LM3692X_PWM_HYSTER_4LSB BIT(4)
+#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2))
+#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3))
+#define LM3692X_PWM_POLARITY BIT(5)
+#define LM3692X_PWM_SAMP_4MHZ BIT(6)
+#define LM3692X_PWM_SAMP_24MHZ BIT(7)
+
+/* Boost Control Bits */
+#define LM3692X_OCP_PROT_1A BIT(0)
+#define LM3692X_OCP_PROT_1_25A BIT(1)
+#define LM3692X_OCP_PROT_1_5A (BIT(0) | BIT(1))
+#define LM3692X_OVP_21V BIT(2)
+#define LM3692X_OVP_25V BIT(3)
+#define LM3692X_OVP_29V (BIT(2) | BIT(3))
+#define LM3692X_MIN_IND_22UH BIT(4)
+#define LM3692X_BOOST_SW_1MHZ BIT(5)
+#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)
+
+/* Fault Control Bits */
+#define LM3692X_FAULT_CTRL_OVP BIT(0)
+#define LM3692X_FAULT_CTRL_OCP BIT(1)
+#define LM3692X_FAULT_CTRL_TSD BIT(2)
+#define LM3692X_FAULT_CTRL_OPEN BIT(3)
+
+/* Fault Flag Bits */
+#define LM3692X_FAULT_FLAG_OVP BIT(0)
+#define LM3692X_FAULT_FLAG_OCP BIT(1)
+#define LM3692X_FAULT_FLAG_TSD BIT(2)
+#define LM3692X_FAULT_FLAG_SHRT BIT(3)
+#define LM3692X_FAULT_FLAG_OPEN BIT(4)
+
+/**
+ * struct lm3692x_led
+ * @lock: Lock for reading/writing the device
+ * @client: Pointer to the I2C client
+ * @led_dev: LED class device pointer
+ * @regmap: Devices register map
+ * @enable_gpio: VDDIO/EN gpio to enable communication interface
+ * @regulator: LED supply regulator pointer
+ * @led_enable: LED sync to be enabled
+ * @model_id: Current device model ID enumerated
+ */
+struct lm3692x_led {
+ struct mutex lock;
+ struct i2c_client *client;
+ struct led_classdev led_dev;
+ struct regmap *regmap;
+ struct gpio_desc *enable_gpio;
+ struct regulator *regulator;
+ int led_enable;
+ int model_id;
+
+ u8 boost_ctrl, brightness_ctrl;
+ bool enabled;
+};
+
+static const struct reg_default lm3692x_reg_defs[] = {
+ {LM3692X_EN, 0xf},
+ {LM3692X_BRT_CTRL, 0x61},
+ {LM3692X_PWM_CTRL, 0x73},
+ {LM3692X_BOOST_CTRL, 0x6f},
+ {LM3692X_AUTO_FREQ_HI, 0x0},
+ {LM3692X_AUTO_FREQ_LO, 0x0},
+ {LM3692X_BL_ADJ_THRESH, 0x0},
+ {LM3692X_BRT_LSB, 0x7},
+ {LM3692X_BRT_MSB, 0xff},
+ {LM3692X_FAULT_CTRL, 0x7},
+};
+
+static const struct regmap_config lm3692x_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = LM3692X_FAULT_FLAGS,
+ .reg_defaults = lm3692x_reg_defs,
+ .num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static int lm3692x_fault_check(struct lm3692x_led *led)
+{
+ int ret;
+ unsigned int read_buf;
+
+ ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
+ if (ret)
+ return ret;
+
+ if (read_buf)
+ dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);
+
+ /* The first read may clear the fault. Check again to see if the fault
+ * still exits and return that value.
+ */
+ regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
+ if (read_buf)
+ dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
+ read_buf);
+
+ return read_buf;
+}
+
+static int lm3692x_leds_enable(struct lm3692x_led *led)
+{
+ int enable_state;
+ int ret, reg_ret;
+
+ if (led->enabled)
+ return 0;
+
+ if (led->regulator) {
+ ret = regulator_enable(led->regulator);
+ if (ret) {
+ dev_err(&led->client->dev,
+ "Failed to enable regulator: %d\n", ret);
+ return ret;
+ }
+ }
+
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 1);
+
+ ret = lm3692x_fault_check(led);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",
+ ret);
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);
+ if (ret)
+ goto out;
+
+ /*
+ * For glitch free operation, the following data should
+ * only be written while LEDx enable bits are 0 and the device enable
+ * bit is set to 1.
+ * per Section 7.5.14 of the data sheet
+ */
+ ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);
+ if (ret)
+ goto out;
+
+ /* Set the brightness to 0 so when enabled the LEDs do not come
+ * on with full brightness.
+ */
+ ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
+ LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL, led->boost_ctrl);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
+ LM3692X_BL_ADJ_POL | LM3692X_RAMP_EN);
+ if (ret)
+ goto out;
+
+ switch (led->led_enable) {
+ case 0:
+ default:
+ if (led->model_id == LM36923_MODEL)
+ enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN |
+ LM36923_LED3_EN;
+ else
+ enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN;
+
+ break;
+ case 1:
+ enable_state = LM3692X_LED1_EN;
+ break;
+ case 2:
+ enable_state = LM3692X_LED2_EN;
+ break;
+
+ case 3:
+ if (led->model_id == LM36923_MODEL) {
+ enable_state = LM36923_LED3_EN;
+ break;
+ }
+
+ ret = -EINVAL;
+ dev_err(&led->client->dev,
+ "LED3 sync not available on this device\n");
+ goto out;
+ }
+
+ ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,
+ enable_state | LM3692X_DEVICE_EN);
+
+ led->enabled = true;
+ return ret;
+out:
+ dev_err(&led->client->dev, "Fail writing initialization values\n");
+
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 0);
+
+ if (led->regulator) {
+ reg_ret = regulator_disable(led->regulator);
+ if (reg_ret)
+ dev_err(&led->client->dev,
+ "Failed to disable regulator: %d\n", reg_ret);
+ }
+
+ return ret;
+}
+
+static int lm3692x_leds_disable(struct lm3692x_led *led)
+{
+ int ret;
+
+ if (!led->enabled)
+ return 0;
+
+ ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);
+ if (ret) {
+ dev_err(&led->client->dev, "Failed to disable regulator: %d\n",
+ ret);
+ return ret;
+ }
+
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 0);
+
+ if (led->regulator) {
+ ret = regulator_disable(led->regulator);
+ if (ret)
+ dev_err(&led->client->dev,
+ "Failed to disable regulator: %d\n", ret);
+ }
+
+ led->enabled = false;
+ return ret;
+}
+
+static int lm3692x_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brt_val)
+{
+ struct lm3692x_led *led =
+ container_of(led_cdev, struct lm3692x_led, led_dev);
+ int ret;
+ int led_brightness_lsb = (brt_val >> 5);
+
+ mutex_lock(&led->lock);
+
+ if (brt_val == 0) {
+ ret = lm3692x_leds_disable(led);
+ goto out;
+ } else {
+ lm3692x_leds_enable(led);
+ }
+
+ ret = lm3692x_fault_check(led);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",
+ ret);
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot write MSB: %d\n", ret);
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot write LSB: %d\n", ret);
+ goto out;
+ }
+out:
+ mutex_unlock(&led->lock);
+ return ret;
+}
+
+static enum led_brightness lm3692x_max_brightness(struct lm3692x_led *led,
+ u32 max_cur)
+{
+ u32 max_code;
+
+ /* see p.12 of LM36922 data sheet for brightness formula */
+ max_code = ((max_cur * 1000) - 37806) / 12195;
+ if (max_code > 0x7FF)
+ max_code = 0x7FF;
+
+ return max_code >> 3;
+}
+
+static int lm3692x_probe_dt(struct lm3692x_led *led)
+{
+ struct fwnode_handle *child = NULL;
+ struct led_init_data init_data = {};
+ u32 ovp, max_cur;
+ int ret;
+
+ led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
+ "enable", GPIOD_OUT_LOW);
+ if (IS_ERR(led->enable_gpio)) {
+ ret = PTR_ERR(led->enable_gpio);
+ dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",
+ ret);
+ return ret;
+ }
+
+ led->regulator = devm_regulator_get_optional(&led->client->dev, "vled");
+ if (IS_ERR(led->regulator)) {
+ ret = PTR_ERR(led->regulator);
+ if (ret != -ENODEV)
+ return dev_err_probe(&led->client->dev, ret,
+ "Failed to get vled regulator\n");
+
+ led->regulator = NULL;
+ }
+
+ led->boost_ctrl = LM3692X_BOOST_SW_1MHZ |
+ LM3692X_BOOST_SW_NO_SHIFT |
+ LM3692X_OCP_PROT_1_5A;
+ ret = device_property_read_u32(&led->client->dev,
+ "ti,ovp-microvolt", &ovp);
+ if (ret) {
+ led->boost_ctrl |= LM3692X_OVP_29V;
+ } else {
+ switch (ovp) {
+ case 17000000:
+ break;
+ case 21000000:
+ led->boost_ctrl |= LM3692X_OVP_21V;
+ break;
+ case 25000000:
+ led->boost_ctrl |= LM3692X_OVP_25V;
+ break;
+ case 29000000:
+ led->boost_ctrl |= LM3692X_OVP_29V;
+ break;
+ default:
+ dev_err(&led->client->dev, "Invalid OVP %d\n", ovp);
+ return -EINVAL;
+ }
+ }
+
+ child = device_get_next_child_node(&led->client->dev, child);
+ if (!child) {
+ dev_err(&led->client->dev, "No LED Child node\n");
+ return -ENODEV;
+ }
+
+ ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
+ if (ret) {
+ fwnode_handle_put(child);
+ dev_err(&led->client->dev, "reg DT property missing\n");
+ return ret;
+ }
+
+ ret = fwnode_property_read_u32(child, "led-max-microamp", &max_cur);
+ led->led_dev.max_brightness = ret ? LED_FULL :
+ lm3692x_max_brightness(led, max_cur);
+
+ init_data.fwnode = child;
+ init_data.devicename = led->client->name;
+ init_data.default_label = ":";
+
+ ret = devm_led_classdev_register_ext(&led->client->dev, &led->led_dev,
+ &init_data);
+ if (ret)
+ dev_err(&led->client->dev, "led register err: %d\n", ret);
+
+ fwnode_handle_put(init_data.fwnode);
+ return ret;
+}
+
+static int lm3692x_probe(struct i2c_client *client)
+{
+ const struct i2c_device_id *id = i2c_client_get_device_id(client);
+ struct lm3692x_led *led;
+ int ret;
+
+ led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ mutex_init(&led->lock);
+ led->client = client;
+ led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
+ led->model_id = id->driver_data;
+ i2c_set_clientdata(client, led);
+
+ led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
+ if (IS_ERR(led->regmap)) {
+ ret = PTR_ERR(led->regmap);
+ dev_err(&client->dev, "Failed to allocate register map: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = lm3692x_probe_dt(led);
+ if (ret)
+ return ret;
+
+ ret = lm3692x_leds_enable(led);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static void lm3692x_remove(struct i2c_client *client)
+{
+ struct lm3692x_led *led = i2c_get_clientdata(client);
+
+ lm3692x_leds_disable(led);
+ mutex_destroy(&led->lock);
+}
+
+static const struct i2c_device_id lm3692x_id[] = {
+ { "lm36922", LM36922_MODEL },
+ { "lm36923", LM36923_MODEL },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lm3692x_id);
+
+static const struct of_device_id of_lm3692x_leds_match[] = {
+ { .compatible = "ti,lm36922", },
+ { .compatible = "ti,lm36923", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
+
+static struct i2c_driver lm3692x_driver = {
+ .driver = {
+ .name = "lm3692x",
+ .of_match_table = of_lm3692x_leds_match,
+ },
+ .probe = lm3692x_probe,
+ .remove = lm3692x_remove,
+ .id_table = lm3692x_id,
+};
+module_i2c_driver(lm3692x_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
+MODULE_LICENSE("GPL v2");