Re: [PATCH v2 8/9] leds: add LM3633 driver
From: Jacek Anaszewski
Date: Fri Nov 27 2015 - 06:19:32 EST
Hi Milo,
Thanks for the update. I have few comments below.
On 11/26/2015 07:57 AM, Milo Kim wrote:
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, eight attributes are used. Sysfs ABI describes it.
- Time domain
: 'pattern_time_delay', 'pattern_time_rise', 'pattern_time_high',
'pattern_time_fall' and 'pattern_time_low'.
- Level domain
: 'pattern_brightness_low' and 'pattern_brightness_high'.
- Start or stop
: 'run_pattern'
LMU fault monitor event handling
--------------------------------
As soon as LMU fault monitoring is done, LMU device is reset. So LED
device should be reinitialized. lm3633_led_fault_monitor_notifier() is
used for this purpose.
Data structure
--------------
ti_lmu_led: LED output channel data.
ti_lmu_led_chip: LED device data. One LED device can have multiple
LED channel data.
Cc: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
Cc: linux-leds@xxxxxxxxxxxxxxx
Cc: Lee Jones <lee.jones@xxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Milo Kim <milo.kim@xxxxxx>
---
Documentation/ABI/testing/sysfs-class-led-lm3633 | 97 +++
drivers/leds/Kconfig | 10 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-lm3633.c | 840 +++++++++++++++++++++++
4 files changed, 948 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..46217d4
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-lm3633
@@ -0,0 +1,97 @@
+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_time_delay
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern startup delay. Please refer to (1).
+ Range is from 0 to 9700. Unit is millisecond.
+
+What: /sys/class/leds/<led>/pattern_time_rise
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern rising dimming time. Please refer to (2).
+ Range is from 0 to 16000. Unit is millisecond.
+
+What: /sys/class/leds/<led>/pattern_time_high
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern high level time. Please refer to (3).
+ It means how much time stays at high level.
+ Range is from 0 to 9700. Unit is millisecond.
+
+What: /sys/class/leds/<led>/pattern_time_fall
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern falling dimming time. Please refer to (4).
+ Range is from 0 to 16000. Unit is millisecond.
+
+What: /sys/class/leds/<led>/pattern_time_low
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern low level time. Please refer to (5).
+ It means how much time stays at low level.
+ Range is from 0 to 9700. Unit is millisecond.
+
+What: /sys/class/leds/<led>/pattern_brightness_high
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern brightness value at high level.
+ Please refer to (a). Range is from 0 to max brightness value.
+
+What: /sys/class/leds/<led>/pattern_brightness_low
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ Set pattern brightness value at low level.
+ Please refer to (b). Range is from 0 to max brightness value.
+
+What: /sys/class/leds/<led>/run_pattern
+Date: Dec 2015
+KernelVersion: 4.5
+Contact: Milo Kim <milo.kim@xxxxxx>
+Description: write only
+ It is used for activating or deactivating programmed LED
+ dimming pattern. Please make sure pattern parameters
+ should be written prior to accessing this attribute.
+
+ 1 : activate programmed pattern
+ 0 : deactivate the pattern
+
+ Example:
+ To run the pattern,
+
+ echo 0 > /sys/class/leds/<led>/pattern_time_delay
+ echo 200 > /sys/class/leds/<led>/pattern_time_rise
+ echo 300 > /sys/class/leds/<led>/pattern_time_high
+ echo 100 > /sys/class/leds/<led>/pattern_time_fall
+ echo 400 > /sys/class/leds/<led>/pattern_time_low
+ echo 0 > /sys/class/leds/<led>/pattern_brightness_low
+ echo 255 > /sys/class/leds/<led>/pattern_brightness_high
+ echo 1 > /sys/class/leds/<led>/run_pattern
+
+ To stop running pattern,
+ echo 0 > /sys/class/leds/<led>/run_pattern
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index b1ab8bd..ed071ac 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 e9d53092..e183b7d 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..9c391ca
--- /dev/null
+++ b/drivers/leds/leds-lm3633.c
@@ -0,0 +1,840 @@
+/*
+ * 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/bitops.h>
+#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_MAX_PWM 255
+#define LM3633_MIN_CURRENT 5000
+#define LM3633_MAX_CURRENT 30000
+#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
+#define LM3633_IMAX_OFFSET 6
+
+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 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
Could you clarify what "string" means here?
+ * @num_leds: Number of LED strings
and here?
+ * @nb: Notifier block for handling LMU fault monitor 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_sources: LED output channel configuration.
+ * Bit mask is set on parsing DT.
+ * @max_brightness: Max brightness value.
+ * Is is determined by led-max-microamp.
+ *
+ * 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;
You have it in the struct led_classdev.
+ unsigned long led_sources;
+ u8 max_brightness;
This is also present in the struct led_classdev.
+};
+
+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)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return regmap_update_bits(regmap, LM3633_REG_ENABLE, mask, mask);
+}
+
+static int lm3633_led_disable_bank(struct ti_lmu_led *lmu_led)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return regmap_update_bits(regmap, LM3633_REG_ENABLE, mask, 0);
+}
+
+static int lm3633_led_config_bank(struct ti_lmu_led *lmu_led)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ 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_sources)) {
+ if (lmu_led->led_sources & group_led[i]) {
+ lmu_led->bank_id = default_id[i];
+ val = 0;
+ } else {
+ lmu_led->bank_id = separate_id[i];
+ val = BIT(i);
+ }
+
+ ret = regmap_update_bits(regmap, LM3633_REG_BANK_SEL,
+ BIT(i), val);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static u8 lm3633_convert_time_to_index(unsigned int msec)
+{
+ u8 idx, offset;
+
+ /*
+ * Find an approximate index
I think that we shouldn't approximate but clamp the msec
to the nearest possible device setting.
+ *
+ * 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 an approximate index by looking up the table */
Similarly here. So you should have an array of the possible msec
values and iterate through it to look for the nearest one.
+ 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 int lm3633_led_update_linear_time(const char *buf,
+ struct ti_lmu_led *lmu_led, u8 reg)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ unsigned long time;
+ u8 offset = lmu_led->bank_id * LM3633_PATTERN_REG_OFFSET;
+
+ /*
+ * 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.
+ */
+
+ if (kstrtoul(buf, 0, &time))
+ return -EINVAL;
+
+ return regmap_write(regmap, reg + offset,
+ lm3633_convert_time_to_index(time));
+}
+
+static int lm3633_led_update_ramp_time(const char *buf,
+ struct ti_lmu_led *lmu_led,
+ u8 mask, u8 shift)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ unsigned long ramp_time;
+ u8 reg, val;
+
+ /*
+ * Register values are index domain, so input time value should be
+ * converted to index.
+ */
+
+ if (kstrtoul(buf, 0, &ramp_time))
+ return -EINVAL;
+
+ 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:
+ return -EINVAL;
+ }
+
+ val = lm3633_convert_ramp_to_index(ramp_time) << shift;
Please add empty line here.
+ return regmap_update_bits(regmap, reg, mask, val);
+}
+
+static ssize_t lm3633_led_store_pattern_time_delay(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_update_linear_time(buf, lmu_led, LM3633_REG_PTN_DELAY);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lm3633_led_store_pattern_time_high(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_update_linear_time(buf, lmu_led,
+ LM3633_REG_PTN_HIGHTIME);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lm3633_led_store_pattern_time_low(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_update_linear_time(buf, lmu_led,
+ LM3633_REG_PTN_LOWTIME);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lm3633_led_store_pattern_time_rise(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_update_ramp_time(buf, lmu_led, LM3633_PTN_RAMPUP_MASK,
+ LM3633_PTN_RAMPUP_SHIFT);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lm3633_led_store_pattern_time_fall(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_update_ramp_time(buf, lmu_led, LM3633_PTN_RAMPDN_MASK,
+ LM3633_PTN_RAMPDN_SHIFT);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static int lm3633_led_set_pattern_brightness(const char *buf,
+ struct ti_lmu_led *lmu_led, u8 reg)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ unsigned long brt;
+ int ret;
+
+ if (kstrtoul(buf, 0, &brt))
+ return -EINVAL;
+
+ ret = lm3633_led_disable_bank(lmu_led);
+ if (ret)
+ return ret;
+
+ brt = min_t(unsigned long, brt, lmu_led->max_brightness);
+
+ return regmap_write(regmap, reg, (u8)brt);
+}
+
+static ssize_t lm3633_led_store_pattern_brightness_low(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ u8 offset = lmu_led->bank_id * LM3633_PATTERN_REG_OFFSET;
+ u8 reg = LM3633_REG_PTN_LOWBRT + offset;
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_set_pattern_brightness(buf, lmu_led, reg);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lm3633_led_store_pattern_brightness_high(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ti_lmu_led *lmu_led = to_ti_lmu_led(dev);
+ u8 reg = LM3633_REG_PTN_HIGHBRT + lmu_led->bank_id;
+ int ret;
+
+ mutex_lock(&lmu_led->chip->lock);
+ ret = lm3633_led_set_pattern_brightness(buf, lmu_led, reg);
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static int lm3633_led_activate_pattern(struct ti_lmu_led *lmu_led)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+ int ret;
+
+ ret = regmap_update_bits(regmap, LM3633_REG_PATTERN, mask, mask);
+ if (ret)
+ return ret;
+
+ return lm3633_led_enable_bank(lmu_led);
+}
+
+static int lm3633_led_deactivate_pattern(struct ti_lmu_led *lmu_led)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u8 mask = lm3633_led_get_enable_mask(lmu_led);
+
+ return regmap_update_bits(regmap, LM3633_REG_PATTERN, mask, 0);
+}
+
+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);
+ unsigned long run;
+ int ret;
+
+ if (kstrtoul(buf, 0, &run))
+ return -EINVAL;
+
+ mutex_lock(&lmu_led->chip->lock);
+
+ if (!run)
+ ret = lm3633_led_deactivate_pattern(lmu_led);
+ else
+ ret = lm3633_led_activate_pattern(lmu_led);
+
+ mutex_unlock(&lmu_led->chip->lock);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+#define LM3633_PATTERN_ATTR(name) \
+DEVICE_ATTR(pattern_##name, S_IWUSR, NULL, lm3633_led_store_pattern_##name)
+
+static LM3633_PATTERN_ATTR(time_delay);
+static LM3633_PATTERN_ATTR(time_rise);
+static LM3633_PATTERN_ATTR(time_high);
+static LM3633_PATTERN_ATTR(time_fall);
+static LM3633_PATTERN_ATTR(time_low);
+static LM3633_PATTERN_ATTR(brightness_low);
+static LM3633_PATTERN_ATTR(brightness_high);
+static DEVICE_ATTR(run_pattern, S_IWUSR, NULL, lm3633_led_run_pattern);
+
+static struct attribute *lm3633_led_attrs[] = {
+ &dev_attr_pattern_time_delay.attr,
+ &dev_attr_pattern_time_rise.attr,
+ &dev_attr_pattern_time_high.attr,
+ &dev_attr_pattern_time_fall.attr,
+ &dev_attr_pattern_time_low.attr,
+ &dev_attr_pattern_brightness_low.attr,
+ &dev_attr_pattern_brightness_high.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)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u8 reg = LM3633_REG_IMAX_LVLED_BASE + lmu_led->bank_id;
+
+ return regmap_write(regmap, reg, LMU_IMAX_30mA);
+}
+
+static int lm3633_led_brightness_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct ti_lmu_led *lmu_led = container_of(cdev, struct ti_lmu_led,
+ cdev);
+ struct ti_lmu_led_chip *chip = lmu_led->chip;
+ struct regmap *regmap = chip->lmu->regmap;
+ u8 reg = LM3633_REG_BRT_LVLED_BASE + lmu_led->bank_id;
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = regmap_write(regmap, reg, brightness);
+ if (ret) {
+ mutex_unlock(&chip->lock);
+ return ret;
+ }
+
+ if (brightness == 0)
+ lm3633_led_disable_bank(lmu_led);
This should be checked at first, as I suppose that disabling
a bank suffices to turn the LED off.
+ else
+ lm3633_led_enable_bank(lmu_led);
+
+ mutex_unlock(&chip->lock);
+
+ return 0;
+}
+
+static int lm3633_led_init(struct ti_lmu_led *lmu_led, int bank_id)
+{
+ struct device *dev = lmu_led->chip->dev;
+ 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 = lmu_led->max_brightness;
+ lmu_led->cdev.brightness_set_blocking = lm3633_led_brightness_set;
+ lmu_led->cdev.groups = lm3633_led_groups;
+ lmu_led->cdev.name = lmu_led->name;
+
+ ret = devm_led_classdev_register(dev, &lmu_led->cdev);
+ if (ret) {
+ dev_err(dev, "LED register err: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void lm3633_led_of_set_label(struct device_node *np,
+ struct ti_lmu_led *lmu_led)
+{
+ const char *name;
+
+ if (!of_property_read_string(np, "label", &name))
+ lmu_led->name = name;
+ else
+ lmu_led->name = np->name;
+}
+
+static int lm3633_led_of_create_channel(struct device_node *np,
+ struct ti_lmu_led *lmu_led)
+{
+ int ret, num_sources;
+ u32 sources[LM3633_MAX_LEDS];
+
+ ret = of_property_count_u32_elems(np, "led-sources");
+ if (ret < 0 || ret > LM3633_MAX_LEDS)
+ return -EINVAL;
+
+ num_sources = ret;
+ ret = of_property_read_u32_array(np, "led-sources", sources,
+ num_sources);
+ if (ret)
+ return ret;
+
+ lmu_led->led_sources = 0;
+ while (num_sources--)
+ set_bit(sources[num_sources], &lmu_led->led_sources);
+
+ return 0;
+}
+
+static u8 lm3633_led_convert_current_to_index(u32 imax_microamp)
+{
+ u8 imax_milliamp = imax_microamp / 1000;
+ const u8 imax_table[] = {
+ LMU_IMAX_6mA, LMU_IMAX_7mA, LMU_IMAX_8mA, LMU_IMAX_9mA,
+ LMU_IMAX_10mA, LMU_IMAX_11mA, LMU_IMAX_12mA, LMU_IMAX_13mA,
+ LMU_IMAX_14mA, LMU_IMAX_15mA, LMU_IMAX_16mA, LMU_IMAX_17mA,
+ LMU_IMAX_18mA, LMU_IMAX_19mA, LMU_IMAX_20mA, LMU_IMAX_21mA,
+ LMU_IMAX_22mA, LMU_IMAX_23mA, LMU_IMAX_24mA, LMU_IMAX_25mA,
+ LMU_IMAX_26mA, LMU_IMAX_27mA, LMU_IMAX_28mA, LMU_IMAX_29mA,
+ };
+
+ /* Valid range is from 5mA to 30mA */
+ if (imax_milliamp <= 5)
+ return LMU_IMAX_5mA;
+
+ if (imax_milliamp >= 30)
+ return LMU_IMAX_30mA;
+
+ return imax_table[imax_milliamp - LM3633_IMAX_OFFSET];
+}
+
+static u8 lm3633_led_scale_max_brightness(struct ti_lmu_led *lmu_led, u32 imax)
+{
+ u8 max_current = lm3633_led_convert_current_to_index(imax);
+ const u8 max_brightness_table[] = {
+ [LMU_IMAX_5mA] = 191,
+ [LMU_IMAX_6mA] = 197,
+ [LMU_IMAX_7mA] = 203,
+ [LMU_IMAX_8mA] = 208,
+ [LMU_IMAX_9mA] = 212,
+ [LMU_IMAX_10mA] = 216,
+ [LMU_IMAX_11mA] = 219,
+ [LMU_IMAX_12mA] = 222,
+ [LMU_IMAX_13mA] = 225,
+ [LMU_IMAX_14mA] = 228,
+ [LMU_IMAX_15mA] = 230,
+ [LMU_IMAX_16mA] = 233,
+ [LMU_IMAX_17mA] = 235,
+ [LMU_IMAX_18mA] = 237,
+ [LMU_IMAX_19mA] = 239,
+ [LMU_IMAX_20mA] = 241,
+ [LMU_IMAX_21mA] = 242,
+ [LMU_IMAX_22mA] = 244,
+ [LMU_IMAX_23mA] = 246,
+ [LMU_IMAX_24mA] = 247,
+ [LMU_IMAX_25mA] = 249,
+ [LMU_IMAX_26mA] = 250,
+ [LMU_IMAX_27mA] = 251,
+ [LMU_IMAX_28mA] = 253,
+ [LMU_IMAX_29mA] = 254,
+ [LMU_IMAX_30mA] = 255,
+ };
After analyzing the subject one more time I think that we need to
change the approach regarding max brightness issue.
At first - we shouldn't fix max current to max possible register value.
Instead we should take led-max-microamp property and write its value
to the [0x22 + bank offset] registers.
With this approach whole 0-255 range of brightness levels will be
valid for the driver.
In effect all LMU_IMAX* enums seem to be not needed.
+ return max_brightness_table[max_current];
+}
+
+static void lm3633_led_of_get_max_brightness(struct device_node *np,
+ struct ti_lmu_led *lmu_led)
+{
+ struct regmap *regmap = lmu_led->chip->lmu->regmap;
+ u32 imax = 0;
+ u8 mode = 0;
+
+ of_property_read_u32(np, "led-max-microamp", &imax);
+
+ if (imax <= LM3633_MIN_CURRENT)
+ imax = LM3633_MIN_CURRENT;
+ else
+ imax = min_t(unsigned int, imax, LM3633_MAX_CURRENT);
+
+ /*
+ * Max brightness is determined by mapping mode - exponential or
+ * linear.
+ */
+ regmap_read(regmap, LM3633_REG_LED_MAPPING_MODE, (unsigned int *)&mode);
+
+ if (mode & LM3633_LED_EXPONENTIAL)
+ lmu_led->max_brightness =
+ lm3633_led_scale_max_brightness(lmu_led, imax);
+ else
+ lmu_led->max_brightness =
+ (imax * LM3633_MAX_PWM) / LM3633_MAX_CURRENT;
+}
+
+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 ret, num_leds;
+ int i = 0;
+
+ 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;
+ each->bank_id = 0;
+ each->chip = chip;
+
+ lm3633_led_of_set_label(child, each);
+
+ ret = lm3633_led_of_create_channel(child, each);
+ if (ret) {
+ of_node_put(np);
+ return ret;
+ }
+
+ lm3633_led_of_get_max_brightness(child, each);
+ i++;
+ }
+
+ chip->lmu_led = lmu_led;
+ chip->num_leds = num_leds;
+
+ return 0;
+}
+
+static int lm3633_led_fault_monitor_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;
+
+ /*
+ * LMU fault monitor driver resets the device, so LED should be
+ * re-configured after fault detection procedure is done.
+ */
+ if (action == LMU_EVENT_MONITOR_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;
+ }
+
+ led_set_brightness(&each->cdev, each->cdev.brightness);
+ }
+ }
+
+ 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;
+
+ mutex_init(&chip->lock);
+
+ 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);
+ return ret;
+ }
+ }
+
+ /*
+ * Notifier callback is required because LED device needs
+ * reconfiguration after open/short circuit fault monitoring
+ * by ti-lmu-fault-monitor driver.
+ */
+ chip->nb.notifier_call = lm3633_led_fault_monitor_notifier;
+ ret = blocking_notifier_chain_register(&chip->lmu->notifier, &chip->nb);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, chip);
+
+ return 0;
+}
+
+static int lm3633_led_remove(struct platform_device *pdev)
+{
+ struct ti_lmu_led_chip *chip = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < chip->num_leds; i++)
+ lm3633_led_deactivate_pattern(chip->lmu_led + i);
+
+ blocking_notifier_chain_unregister(&chip->lmu->notifier, &chip->nb);
+
+ return 0;
+}
+
+static struct platform_driver lm3633_led_driver = {
+ .probe = lm3633_led_probe,
+ .remove = lm3633_led_remove,
+ .driver = {
+ .name = "lm3633-leds",
+ },
+};
+
+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");
--
Best Regards,
Jacek Anaszewski
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