[PATCH 15/16] leds: add LM3633 driver

From: Milo Kim
Date: Mon Nov 02 2015 - 00:02:41 EST


LM3633 LED driver supports generic LED functions and pattern generation.
Pattern is generated through the sysfs. ABI documentation is also added.

Device creation from device tree
--------------------------------
LED channel name, LED string usage and max current settings are
configured inside the DT.

LED dimming pattern generation
------------------------------
LM3633 supports programmable dimming pattern generator.
To enable it, three attributes are used.
'pattern_times', 'pattern_levels' and 'run_pattern'.
Sysfs ABI describes it.

LMU HWMON event handling
------------------------
As soon as LMU HWMON operation is done, LMU HWMON driver sends the event,
'LMU_EVENT_HWMON_DONE'. Then, LM3633 device should be reinitialized
because the device was reset by LMU HWMON driver.
lm3633_led_hwmon_notifier() handles this event.

Data structure
--------------
ti_lmu_led_chip: LED device data.
ti_lmu_led: LED output channel data.
One LED device can have multiple LED channels.

Cc: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
Cc: linux-leds@xxxxxxxxxxxxxxx
Cc: Lee Jones <lee.jones@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Milo Kim <milo.kim@xxxxxx>
---
Documentation/ABI/testing/sysfs-class-led-lm3633 | 60 ++
drivers/leds/Kconfig | 10 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-lm3633.c | 749 +++++++++++++++++++++++
4 files changed, 820 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-led-lm3633
create mode 100644 drivers/leds/leds-lm3633.c

diff --git a/Documentation/ABI/testing/sysfs-class-led-lm3633 b/Documentation/ABI/testing/sysfs-class-led-lm3633
new file mode 100644
index 0000000..c1d8759
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-lm3633
@@ -0,0 +1,60 @@
+LM3633 LED driver generates programmable pattern via the sysfs.
+
+LED Pattern Generator Structure
+
+ (3)
+ (a) ---------------> ___________
+ / \
+ (2) / \ (4)
+ (b) ----> _________/ \_________ ...
+ (1) (5)
+
+ |<----- period -----> |
+
+What: /sys/class/leds/<led>/pattern_times
+Date: Oct 2015
+KernelVersion: 4.3
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: read/write
+ Set pattern time dimension. There are five arguments.
+ (1) startup delay
+ (2) rising dimming time
+ (3) how much time stays at high level
+ (4) falling dimming time
+ (5) how much time stays at low level
+ Ranges are
+ (1), (3), (5): 0 ~ 10000. Unit is millisecond.
+ (2), (4): 0 ~ 16000. Unit is millisecond.
+
+ Example:
+ No delay, rising 200ms, high 300ms, falling 100ms, low 400ms.
+ echo "0 200 300 100 400" > /sys/class/leds/<led>/pattern_times
+
+ cat /sys/class/leds/<led>/pattern_times
+ delay: 0, rise: 200, high: 300, fall: 100, low: 400
+
+What: /sys/class/leds/<led>/pattern_levels
+Date: Oct 2015
+KernelVersion: 4.3
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: read/write
+ Set pattern level(brightness). There are two arguments.
+ (a) Low brightness level
+ (b) High brightness level
+ Ranges are from 0 to 255.
+
+ Example:
+ Low level is 0, high level is 255.
+ echo "0 255" > /sys/class/leds/<led>/pattern_levels
+
+ cat /sys/class/leds/<led>/pattern_levels
+ low brightness: 0, high brightness: 255
+
+What: /sys/class/leds/<led>/run_pattern
+Date: Oct 2015
+KernelVersion: 4.3
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ After 'pattern_times' and 'pattern_levels' are updated,
+ run the pattern by writing 1 to 'run_pattern'.
+ To stop running pattern, writes 0 to 'run_pattern'.
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 42990f2..bc41a0e 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -88,6 +88,16 @@ config LEDS_LM3533
hardware-accelerated blinking with maximum on and off periods of 9.8
and 77 seconds respectively.

+config LEDS_LM3633
+ tristate "LED support for the TI LM3633 LMU"
+ depends on LEDS_CLASS
+ depends on MFD_TI_LMU
+ help
+ This option enables support for the LEDs on the LM3633.
+ LM3633 has 6 low voltage indicator LEDs.
+ All low voltage current sinks can have a programmable pattern
+ modulated onto LED output strings.
+
config LEDS_LM3642
tristate "LED support for LM3642 Chip"
depends on LEDS_CLASS && I2C
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index b503f92..984f44a 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o
obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o
obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o
obj-$(CONFIG_LEDS_LM3533) += leds-lm3533.o
+obj-$(CONFIG_LEDS_LM3633) += leds-lm3633.o
obj-$(CONFIG_LEDS_LM3642) += leds-lm3642.o
obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o
obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c24xx.o
diff --git a/drivers/leds/leds-lm3633.c b/drivers/leds/leds-lm3633.c
new file mode 100644
index 0000000..66da609
--- /dev/null
+++ b/drivers/leds/leds-lm3633.c
@@ -0,0 +1,749 @@
+/*
+ * TI LM3633 LED driver
+ *
+ * Copyright 2015 Texas Instruments
+ *
+ * Author: Milo Kim <milo.kim@xxxxxx>
+ *
+ * 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/kernel.h>
+#include <linux/leds.h>
+#include <linux/mfd/ti-lmu.h>
+#include <linux/mfd/ti-lmu-register.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define LM3633_LED_MAX_BRIGHTNESS 255
+#define LM3633_DEFAULT_LED_NAME "indicator"
+#define LM3633_MAX_PERIOD 9700
+#define LM3633_SHORT_TIMESTEP 16
+#define LM3633_LONG_TIMESTEP 131
+#define LM3633_TIME_OFFSET 61
+#define LM3633_PATTERN_REG_OFFSET 16
+
+enum lm3633_led_bank_id {
+ LM3633_LED_BANK_C,
+ LM3633_LED_BANK_D,
+ LM3633_LED_BANK_E,
+ LM3633_LED_BANK_F,
+ LM3633_LED_BANK_G,
+ LM3633_LED_BANK_H,
+ LM3633_MAX_LEDS,
+};
+
+struct lm3633_pattern_time {
+ unsigned int delay;
+ unsigned int rise;
+ unsigned int high;
+ unsigned int fall;
+ unsigned int low;
+};
+
+struct lm3633_pattern_level {
+ u8 low;
+ u8 high;
+};
+
+/**
+ * struct ti_lmu_led_chip
+ *
+ * @dev: Parent device pointer
+ * @lmu: LMU structure. Used for register R/W access.
+ * @lock: Secure handling for multiple user interface access
+ * @lmu_led: Multiple LED strings
+ * @num_leds: Number of LED strings
+ * @nb: Notifier block for handling hwmon event
+ *
+ * One LED chip can have multiple LED strings.
+ */
+struct ti_lmu_led_chip {
+ struct device *dev;
+ struct ti_lmu *lmu;
+ struct mutex lock;
+ struct ti_lmu_led *lmu_led;
+ int num_leds;
+ struct notifier_block nb;
+};
+
+/**
+ * struct ti_lmu_led
+ *
+ * @chip: Pointer to parent LED device
+ * @bank_id: LED bank ID
+ * @cdev: LED subsystem device structure
+ * @name: LED channel name
+ * @led_string: LED string configuration.
+ * Bit mask is set on parsing DT.
+ * @imax: [Optional] Max current index.
+ * It's result of ti_lmu_get_current_code().
+ * @work: Used for scheduling brightness control
+ * @brightness: Brightness value
+ * @time: Pattern time dimension
+ * @level: Pattern level dimension
+ *
+ * Each LED device has its own channel configuration.
+ * For chip control, parent chip data structure is used.
+ */
+struct ti_lmu_led {
+ struct ti_lmu_led_chip *chip;
+ enum lm3633_led_bank_id bank_id;
+ struct led_classdev cdev;
+ const char *name;
+
+ unsigned long led_string; /* bit OR mask of LMU_LVLEDx */;
+ #define LMU_LVLED1 BIT(0)
+ #define LMU_LVLED2 BIT(1)
+ #define LMU_LVLED3 BIT(2)
+ #define LMU_LVLED4 BIT(3)
+ #define LMU_LVLED5 BIT(4)
+ #define LMU_LVLED6 BIT(5)
+
+ struct work_struct work;
+ enum led_brightness brightness;
+ enum ti_lmu_max_current imax;
+
+ /* Pattern specific data */
+ struct lm3633_pattern_time time;
+ struct lm3633_pattern_level level;
+};
+
+static struct ti_lmu_led *to_ti_lmu_led(struct device *dev)
+{
+ struct led_classdev *cdev = dev_get_drvdata(dev);
+
+ return container_of(cdev, struct ti_lmu_led, cdev);
+}
+
+static u8 lm3633_led_get_enable_mask(struct ti_lmu_led *lmu_led)
+{
+ return 1 << (lmu_led->bank_id + LM3633_LED_BANK_OFFSET);
+}
+
+static int lm3633_led_enable_bank(struct ti_lmu_led *lmu_led)
+{
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return ti_lmu_update_bits(lmu_led->chip->lmu, LM3633_REG_ENABLE,
+ mask, mask);
+}
+
+static int lm3633_led_disable_bank(struct ti_lmu_led *lmu_led)
+{
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return ti_lmu_update_bits(lmu_led->chip->lmu, LM3633_REG_ENABLE,
+ mask, 0);
+}
+
+static int lm3633_led_enable_pattern(struct ti_lmu_led *lmu_led)
+{
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return ti_lmu_update_bits(lmu_led->chip->lmu, LM3633_REG_PATTERN, mask,
+ mask);
+}
+
+static int lm3633_led_disable_pattern(struct ti_lmu_led *lmu_led)
+{
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return ti_lmu_update_bits(lmu_led->chip->lmu, LM3633_REG_PATTERN, mask,
+ 0);
+}
+
+static int lm3633_led_config_bank(struct ti_lmu_led *lmu_led)
+{
+ const u8 group_led[] = { 0, BIT(0), BIT(0), 0, BIT(3), BIT(3), };
+ const enum lm3633_led_bank_id default_id[] = {
+ LM3633_LED_BANK_C, LM3633_LED_BANK_C, LM3633_LED_BANK_C,
+ LM3633_LED_BANK_F, LM3633_LED_BANK_F, LM3633_LED_BANK_F,
+ };
+ const enum lm3633_led_bank_id separate_id[] = {
+ LM3633_LED_BANK_C, LM3633_LED_BANK_D, LM3633_LED_BANK_E,
+ LM3633_LED_BANK_F, LM3633_LED_BANK_G, LM3633_LED_BANK_H,
+ };
+ int i, ret;
+ u8 val;
+
+ /*
+ * Check configured LED string and assign control bank
+ *
+ * Each LED is tied with other LEDS (group):
+ * the default control bank is assigned
+ *
+ * Otherwise:
+ * separate bank is assigned
+ */
+
+ for (i = 0; i < LM3633_MAX_LEDS; i++) {
+ /* LED 0 and LED 3 are fixed, so no assignment is required */
+ if (i == 0 || i == 3)
+ continue;
+
+ if (test_bit(i, &lmu_led->led_string)) {
+ if (lmu_led->led_string & group_led[i]) {
+ lmu_led->bank_id = default_id[i];
+ val = 0;
+ } else {
+ lmu_led->bank_id = separate_id[i];
+ val = BIT(i);
+ }
+
+ ret = ti_lmu_update_bits(lmu_led->chip->lmu,
+ LM3633_REG_BANK_SEL,
+ BIT(i), val);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static ssize_t lm3633_led_show_pattern_times(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+
+ return sprintf(buf,
+ "delay: %u, rise: %u, high: %u, fall: %u, low: %u\n",
+ lmu_led->time.delay, lmu_led->time.rise,
+ lmu_led->time.high, lmu_led->time.fall,
+ lmu_led->time.low);
+}
+
+static u8 lm3633_convert_time_to_index(unsigned int msec)
+{
+ u8 idx, offset;
+
+ /*
+ * Find appropriate register index around input time value
+ *
+ * 0 <= time <= 1000 : 16ms step
+ * 1000 < time <= 9700 : 131ms step, base index is 61
+ */
+
+ msec = min_t(int, msec, LM3633_MAX_PERIOD);
+
+ if (msec <= 1000) {
+ idx = msec / LM3633_SHORT_TIMESTEP;
+ if (idx > 1)
+ idx--;
+ offset = 0;
+ } else {
+ idx = (msec - 1000) / LM3633_LONG_TIMESTEP;
+ offset = LM3633_TIME_OFFSET;
+ }
+
+ return idx + offset;
+}
+
+static u8 lm3633_convert_ramp_to_index(unsigned int msec)
+{
+ const int ramp_table[] = { 2, 250, 500, 1000, 2000, 4000, 8000, 16000 };
+ int size = ARRAY_SIZE(ramp_table);
+ int i;
+
+ if (msec <= ramp_table[0])
+ return 0;
+
+ if (msec > ramp_table[size - 1])
+ return size - 1;
+
+ for (i = 1; i < size; i++) {
+ if (msec == ramp_table[i])
+ return i;
+
+ /* Find the most closest value by looking up the table */
+ if (msec > ramp_table[i - 1] && msec < ramp_table[i]) {
+ if (msec - ramp_table[i - 1] < ramp_table[i] - msec)
+ return i - 1;
+ else
+ return i;
+ }
+ }
+
+ return 0;
+}
+
+static ssize_t lm3633_led_store_pattern_times(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ struct ti_lmu_led_chip *chip = lmu_led->chip;
+ struct lm3633_pattern_time *time = &lmu_led->time;
+ u8 offset = lmu_led->bank_id * LM3633_PATTERN_REG_OFFSET;
+ int ret;
+ u8 reg, val;
+
+ /*
+ * Sequence
+ *
+ * 1) Read pattern time data (unit: msec)
+ * 2) Update DELAY register
+ * 3) Update HIGH TIME register
+ * 4) Update LOW TIME register
+ * 5) Update RAMP TIME registers
+ *
+ * Time register addresses need offset number based on the LED bank.
+ * Register values are index domain, so input time value should be
+ * converted to index.
+ * Please note that ramp register address has no offset value.
+ */
+
+ ret = sscanf(buf, "%u %u %u %u %u", &time->delay, &time->rise,
+ &time->high, &time->fall, &time->low);
+ if (ret != 5)
+ return -EINVAL;
+
+ mutex_lock(&chip->lock);
+
+ reg = LM3633_REG_PTN_DELAY + offset;
+ val = lm3633_convert_time_to_index(time->delay);
+ ret = ti_lmu_write_byte(chip->lmu, reg, val);
+ if (ret)
+ goto skip;
+
+ reg = LM3633_REG_PTN_HIGHTIME + offset;
+ val = lm3633_convert_time_to_index(time->high);
+ ret = ti_lmu_write_byte(chip->lmu, reg, val);
+ if (ret)
+ goto skip;
+
+ reg = LM3633_REG_PTN_LOWTIME + offset;
+ val = lm3633_convert_time_to_index(time->low);
+ ret = ti_lmu_write_byte(chip->lmu, reg, val);
+ if (ret)
+ goto skip;
+
+ switch (lmu_led->bank_id) {
+ case LM3633_LED_BANK_C:
+ case LM3633_LED_BANK_D:
+ case LM3633_LED_BANK_E:
+ reg = LM3633_REG_PTN0_RAMP;
+ break;
+ case LM3633_LED_BANK_F:
+ case LM3633_LED_BANK_G:
+ case LM3633_LED_BANK_H:
+ reg = LM3633_REG_PTN1_RAMP;
+ break;
+ default:
+ ret = -EINVAL;
+ goto skip;
+ }
+
+ val = lm3633_convert_ramp_to_index(time->rise);
+ ret = ti_lmu_update_bits(chip->lmu, reg, LM3633_PTN_RAMPUP_MASK,
+ val << LM3633_PTN_RAMPUP_SHIFT);
+ if (ret)
+ goto skip;
+
+ val = lm3633_convert_ramp_to_index(time->fall);
+ ret = ti_lmu_update_bits(chip->lmu, reg, LM3633_PTN_RAMPDN_MASK,
+ val << LM3633_PTN_RAMPDN_SHIFT);
+ if (ret)
+ goto skip;
+
+ mutex_unlock(&chip->lock);
+ return len;
+
+skip:
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static ssize_t lm3633_led_show_pattern_levels(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+
+ return sprintf(buf, "low brightness: %u, high brightness: %u\n",
+ lmu_led->level.low, lmu_led->level.high);
+}
+
+static ssize_t lm3633_led_store_pattern_levels(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ struct ti_lmu_led_chip *chip = lmu_led->chip;
+ unsigned int low, high;
+ u8 reg, offset, val;
+ int ret;
+
+ /*
+ * Sequence
+ *
+ * 1) Read pattern level data
+ * 2) Disable a bank before programming a pattern
+ * 3) Update LOW BRIGHTNESS register
+ * 4) Update HIGH BRIGHTNESS register
+ *
+ * Level register addresses have offset number based on the LED bank.
+ */
+
+ ret = sscanf(buf, "%u %u", &low, &high);
+ if (ret != 2)
+ return -EINVAL;
+
+ low = min_t(unsigned int, low, LM3633_LED_MAX_BRIGHTNESS);
+ high = min_t(unsigned int, high, LM3633_LED_MAX_BRIGHTNESS);
+ lmu_led->level.low = (u8)low;
+ lmu_led->level.high = (u8)high;
+
+ mutex_lock(&chip->lock);
+ ret = lm3633_led_disable_bank(lmu_led);
+ if (ret)
+ goto skip;
+
+ offset = lmu_led->bank_id * LM3633_PATTERN_REG_OFFSET;
+ reg = LM3633_REG_PTN_LOWBRT + offset;
+ val = lmu_led->level.low;
+ ret = ti_lmu_write_byte(chip->lmu, reg, val);
+ if (ret)
+ goto skip;
+
+ offset = lmu_led->bank_id;
+ reg = LM3633_REG_PTN_HIGHBRT + offset;
+ val = lmu_led->level.high;
+ ret = ti_lmu_write_byte(chip->lmu, reg, val);
+ if (ret)
+ goto skip;
+
+ mutex_unlock(&chip->lock);
+ return len;
+
+skip:
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static ssize_t lm3633_led_run_pattern(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ struct ti_lmu_led_chip *chip = lmu_led->chip;
+ unsigned long enable;
+ int ret;
+
+ if (kstrtoul(buf, 0, &enable))
+ return -EINVAL;
+
+ mutex_lock(&chip->lock);
+
+ if (enable)
+ ret = lm3633_led_enable_pattern(lmu_led);
+ else
+ ret = lm3633_led_disable_pattern(lmu_led);
+
+ if (ret) {
+ mutex_unlock(&chip->lock);
+ return ret;
+ }
+
+ if (enable)
+ lm3633_led_enable_bank(lmu_led);
+
+ mutex_unlock(&chip->lock);
+
+ return len;
+}
+
+static DEVICE_ATTR(pattern_times, S_IRUGO | S_IWUSR,
+ lm3633_led_show_pattern_times,
+ lm3633_led_store_pattern_times);
+static DEVICE_ATTR(pattern_levels, S_IRUGO | S_IWUSR,
+ lm3633_led_show_pattern_levels,
+ lm3633_led_store_pattern_levels);
+static DEVICE_ATTR(run_pattern, S_IWUSR, NULL,
+ lm3633_led_run_pattern);
+
+static struct attribute *lm3633_led_attrs[] = {
+ &dev_attr_pattern_times.attr,
+ &dev_attr_pattern_levels.attr,
+ &dev_attr_run_pattern.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(lm3633_led); /* lm3633_led_groups */
+
+static int lm3633_led_set_max_current(struct ti_lmu_led *lmu_led)
+{
+ u8 reg = LM3633_REG_IMAX_LVLED_BASE + lmu_led->bank_id;
+
+ return ti_lmu_write_byte(lmu_led->chip->lmu, reg, lmu_led->imax);
+}
+
+static void lm3633_led_work(struct work_struct *work)
+{
+ struct ti_lmu_led *lmu_led = container_of(work, struct ti_lmu_led,
+ work);
+ struct ti_lmu_led_chip *chip = lmu_led->chip;
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = ti_lmu_write_byte(chip->lmu,
+ LM3633_REG_BRT_LVLED_BASE + lmu_led->bank_id,
+ lmu_led->brightness);
+ if (ret) {
+ mutex_unlock(&chip->lock);
+ return;
+ }
+
+ if (lmu_led->brightness == 0)
+ lm3633_led_disable_bank(lmu_led);
+ else
+ lm3633_led_enable_bank(lmu_led);
+
+ mutex_unlock(&chip->lock);
+}
+
+static void lm3633_led_brightness_set(struct led_classdev *cdev,
+ enum led_brightness brt_val)
+{
+ struct ti_lmu_led *lmu_led = container_of(cdev, struct ti_lmu_led,
+ cdev);
+
+ lmu_led->brightness = brt_val;
+ schedule_work(&lmu_led->work);
+}
+
+static int lm3633_led_init(struct ti_lmu_led *lmu_led, int bank_id)
+{
+ struct device *dev = lmu_led->chip->dev;
+ char name[12];
+ int ret;
+
+ /*
+ * Sequence
+ *
+ * 1) Configure LED bank which is used for brightness control
+ * 2) Set max current for each output channel
+ * 3) Add LED device
+ */
+
+ ret = lm3633_led_config_bank(lmu_led);
+ if (ret) {
+ dev_err(dev, "Output bank register err: %d\n", ret);
+ return ret;
+ }
+
+ ret = lm3633_led_set_max_current(lmu_led);
+ if (ret) {
+ dev_err(dev, "Set max current err: %d\n", ret);
+ return ret;
+ }
+
+ lmu_led->cdev.max_brightness = LM3633_LED_MAX_BRIGHTNESS;
+ lmu_led->cdev.brightness_set = lm3633_led_brightness_set;
+ lmu_led->cdev.groups = lm3633_led_groups;
+
+ if (lmu_led->name) {
+ lmu_led->cdev.name = lmu_led->name;
+ } else {
+ snprintf(name, sizeof(name), "%s:%d", LM3633_DEFAULT_LED_NAME,
+ bank_id);
+ lmu_led->cdev.name = name;
+ }
+
+ ret = led_classdev_register(dev, &lmu_led->cdev);
+ if (ret) {
+ dev_err(dev, "LED register err: %d\n", ret);
+ return ret;
+ }
+
+ INIT_WORK(&lmu_led->work, lm3633_led_work);
+
+ return 0;
+}
+
+static int lm3633_led_of_create(struct ti_lmu_led_chip *chip,
+ struct device_node *np)
+{
+ struct device_node *child;
+ struct device *dev = chip->dev;
+ struct ti_lmu_led *lmu_led, *each;
+ int num_leds;
+ int i = 0;
+ u32 imax;
+
+ if (!np)
+ return -ENODEV;
+
+ num_leds = of_get_child_count(np);
+ if (num_leds == 0 || num_leds > LM3633_MAX_LEDS) {
+ dev_err(dev, "Invalid number of LEDs: %d\n", num_leds);
+ return -EINVAL;
+ }
+
+ lmu_led = devm_kzalloc(dev, sizeof(*lmu_led) * num_leds, GFP_KERNEL);
+ if (!lmu_led)
+ return -ENOMEM;
+
+ for_each_child_of_node(np, child) {
+ each = lmu_led + i;
+
+ of_property_read_string(child, "channel-name", &each->name);
+
+ /* Make LED strings */
+ each->led_string = 0;
+ if (of_property_read_bool(child, "lvled1-used"))
+ each->led_string |= LMU_LVLED1;
+ if (of_property_read_bool(child, "lvled2-used"))
+ each->led_string |= LMU_LVLED2;
+ if (of_property_read_bool(child, "lvled3-used"))
+ each->led_string |= LMU_LVLED3;
+ if (of_property_read_bool(child, "lvled4-used"))
+ each->led_string |= LMU_LVLED4;
+ if (of_property_read_bool(child, "lvled5-used"))
+ each->led_string |= LMU_LVLED5;
+ if (of_property_read_bool(child, "lvled6-used"))
+ each->led_string |= LMU_LVLED6;
+
+ imax = 0;
+ of_property_read_u32(child, "led-max-microamp", &imax);
+ each->imax = ti_lmu_get_current_code(imax);
+
+ each->bank_id = 0;
+ each->chip = chip;
+ i++;
+ }
+
+ chip->lmu_led = lmu_led;
+ chip->num_leds = num_leds;
+
+ return 0;
+}
+
+static int lm3633_led_hwmon_notifier(struct notifier_block *nb,
+ unsigned long action, void *unused)
+{
+ struct ti_lmu_led_chip *chip = container_of(nb, struct ti_lmu_led_chip,
+ nb);
+ struct ti_lmu_led *each;
+ int i, ret;
+
+ /* LED should be reconfigured after hwmon procedure is done */
+ if (action == LMU_EVENT_HWMON_DONE) {
+ for (i = 0; i < chip->num_leds; i++) {
+ each = chip->lmu_led + i;
+ ret = lm3633_led_config_bank(each);
+ if (ret) {
+ dev_err(chip->dev,
+ "Output bank register err: %d\n", ret);
+ return NOTIFY_STOP;
+ }
+
+ ret = lm3633_led_set_max_current(each);
+ if (ret) {
+ dev_err(chip->dev, "Set max current err: %d\n",
+ ret);
+ return NOTIFY_STOP;
+ }
+ }
+ }
+
+ return NOTIFY_OK;
+}
+
+static int lm3633_led_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ti_lmu *lmu = dev_get_drvdata(dev->parent);
+ struct ti_lmu_led_chip *chip;
+ struct ti_lmu_led *each;
+ int i, ret;
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->dev = dev;
+ chip->lmu = lmu;
+
+ ret = lm3633_led_of_create(chip, dev->of_node);
+ if (ret)
+ return ret;
+
+ /*
+ * Notifier callback is required because LED device needs
+ * reconfiguration after opened/shorted circuit fault monitoring
+ * by ti-lmu-hwmon driver.
+ */
+ chip->nb.notifier_call = lm3633_led_hwmon_notifier;
+ ret = blocking_notifier_chain_register(&chip->lmu->notifier, &chip->nb);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < chip->num_leds; i++) {
+ each = chip->lmu_led + i;
+ ret = lm3633_led_init(each, i);
+ if (ret) {
+ dev_err(dev, "LED initialization err: %d\n", ret);
+ goto cleanup_leds;
+ }
+ }
+
+ mutex_init(&chip->lock);
+ platform_set_drvdata(pdev, chip);
+
+ return 0;
+
+cleanup_leds:
+ while (--i >= 0) {
+ each = chip->lmu_led + i;
+ led_classdev_unregister(&each->cdev);
+ }
+ return ret;
+}
+
+static int lm3633_led_remove(struct platform_device *pdev)
+{
+ struct ti_lmu_led_chip *chip = platform_get_drvdata(pdev);
+ struct ti_lmu_led *each;
+ int i;
+
+ blocking_notifier_chain_unregister(&chip->lmu->notifier, &chip->nb);
+
+ for (i = 0; i < chip->num_leds; i++) {
+ each = chip->lmu_led + i;
+ led_classdev_unregister(&each->cdev);
+ flush_work(&each->work);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id lm3633_led_of_match[] = {
+ { .compatible = "ti,lm3633-leds" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, lm3633_led_of_match);
+
+static struct platform_driver lm3633_led_driver = {
+ .probe = lm3633_led_probe,
+ .remove = lm3633_led_remove,
+ .driver = {
+ .name = "lm3633-leds",
+ .of_match_table = lm3633_led_of_match,
+ },
+};
+
+module_platform_driver(lm3633_led_driver);
+
+MODULE_DESCRIPTION("TI LM3633 LED Driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:lm3633-leds");
--
1.9.1

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