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Diffstat (limited to 'kernel/drivers/leds/leds-lp55xx-common.c')
-rw-r--r--kernel/drivers/leds/leds-lp55xx-common.c599
1 files changed, 599 insertions, 0 deletions
diff --git a/kernel/drivers/leds/leds-lp55xx-common.c b/kernel/drivers/leds/leds-lp55xx-common.c
new file mode 100644
index 000000000..77c26bc32
--- /dev/null
+++ b/kernel/drivers/leds/leds-lp55xx-common.c
@@ -0,0 +1,599 @@
+/*
+ * LP5521/LP5523/LP55231/LP5562 Common Driver
+ *
+ * Copyright 2012 Texas Instruments
+ *
+ * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+ *
+ * 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.
+ *
+ * Derived from leds-lp5521.c, leds-lp5523.c
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/platform_data/leds-lp55xx.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+
+#include "leds-lp55xx-common.h"
+
+/* External clock rate */
+#define LP55XX_CLK_32K 32768
+
+static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
+{
+ return container_of(cdev, struct lp55xx_led, cdev);
+}
+
+static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
+{
+ return cdev_to_lp55xx_led(dev_get_drvdata(dev));
+}
+
+static void lp55xx_reset_device(struct lp55xx_chip *chip)
+{
+ struct lp55xx_device_config *cfg = chip->cfg;
+ u8 addr = cfg->reset.addr;
+ u8 val = cfg->reset.val;
+
+ /* no error checking here because no ACK from the device after reset */
+ lp55xx_write(chip, addr, val);
+}
+
+static int lp55xx_detect_device(struct lp55xx_chip *chip)
+{
+ struct lp55xx_device_config *cfg = chip->cfg;
+ u8 addr = cfg->enable.addr;
+ u8 val = cfg->enable.val;
+ int ret;
+
+ ret = lp55xx_write(chip, addr, val);
+ if (ret)
+ return ret;
+
+ usleep_range(1000, 2000);
+
+ ret = lp55xx_read(chip, addr, &val);
+ if (ret)
+ return ret;
+
+ if (val != cfg->enable.val)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int lp55xx_post_init_device(struct lp55xx_chip *chip)
+{
+ struct lp55xx_device_config *cfg = chip->cfg;
+
+ if (!cfg->post_init_device)
+ return 0;
+
+ return cfg->post_init_device(chip);
+}
+
+static ssize_t lp55xx_show_current(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct lp55xx_led *led = dev_to_lp55xx_led(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);
+}
+
+static ssize_t lp55xx_store_current(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct lp55xx_led *led = dev_to_lp55xx_led(dev);
+ struct lp55xx_chip *chip = led->chip;
+ unsigned long curr;
+
+ if (kstrtoul(buf, 0, &curr))
+ return -EINVAL;
+
+ if (curr > led->max_current)
+ return -EINVAL;
+
+ if (!chip->cfg->set_led_current)
+ return len;
+
+ mutex_lock(&chip->lock);
+ chip->cfg->set_led_current(led, (u8)curr);
+ mutex_unlock(&chip->lock);
+
+ return len;
+}
+
+static ssize_t lp55xx_show_max_current(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct lp55xx_led *led = dev_to_lp55xx_led(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", led->max_current);
+}
+
+static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, lp55xx_show_current,
+ lp55xx_store_current);
+static DEVICE_ATTR(max_current, S_IRUGO , lp55xx_show_max_current, NULL);
+
+static struct attribute *lp55xx_led_attrs[] = {
+ &dev_attr_led_current.attr,
+ &dev_attr_max_current.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(lp55xx_led);
+
+static void lp55xx_set_brightness(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
+
+ led->brightness = (u8)brightness;
+ schedule_work(&led->brightness_work);
+}
+
+static int lp55xx_init_led(struct lp55xx_led *led,
+ struct lp55xx_chip *chip, int chan)
+{
+ struct lp55xx_platform_data *pdata = chip->pdata;
+ struct lp55xx_device_config *cfg = chip->cfg;
+ struct device *dev = &chip->cl->dev;
+ char name[32];
+ int ret;
+ int max_channel = cfg->max_channel;
+
+ if (chan >= max_channel) {
+ dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
+ return -EINVAL;
+ }
+
+ if (pdata->led_config[chan].led_current == 0)
+ return 0;
+
+ led->led_current = pdata->led_config[chan].led_current;
+ led->max_current = pdata->led_config[chan].max_current;
+ led->chan_nr = pdata->led_config[chan].chan_nr;
+ led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
+
+ if (led->chan_nr >= max_channel) {
+ dev_err(dev, "Use channel numbers between 0 and %d\n",
+ max_channel - 1);
+ return -EINVAL;
+ }
+
+ led->cdev.brightness_set = lp55xx_set_brightness;
+ led->cdev.groups = lp55xx_led_groups;
+
+ if (pdata->led_config[chan].name) {
+ led->cdev.name = pdata->led_config[chan].name;
+ } else {
+ snprintf(name, sizeof(name), "%s:channel%d",
+ pdata->label ? : chip->cl->name, chan);
+ led->cdev.name = name;
+ }
+
+ ret = led_classdev_register(dev, &led->cdev);
+ if (ret) {
+ dev_err(dev, "led register err: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
+{
+ struct lp55xx_chip *chip = context;
+ struct device *dev = &chip->cl->dev;
+ enum lp55xx_engine_index idx = chip->engine_idx;
+
+ if (!fw) {
+ dev_err(dev, "firmware request failed\n");
+ goto out;
+ }
+
+ /* handling firmware data is chip dependent */
+ mutex_lock(&chip->lock);
+
+ chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
+ chip->fw = fw;
+ if (chip->cfg->firmware_cb)
+ chip->cfg->firmware_cb(chip);
+
+ mutex_unlock(&chip->lock);
+
+out:
+ /* firmware should be released for other channel use */
+ release_firmware(chip->fw);
+}
+
+static int lp55xx_request_firmware(struct lp55xx_chip *chip)
+{
+ const char *name = chip->cl->name;
+ struct device *dev = &chip->cl->dev;
+
+ return request_firmware_nowait(THIS_MODULE, true, name, dev,
+ GFP_KERNEL, chip, lp55xx_firmware_loaded);
+}
+
+static ssize_t lp55xx_show_engine_select(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+
+ return sprintf(buf, "%d\n", chip->engine_idx);
+}
+
+static ssize_t lp55xx_store_engine_select(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+ unsigned long val;
+ int ret;
+
+ if (kstrtoul(buf, 0, &val))
+ return -EINVAL;
+
+ /* select the engine to be run */
+
+ switch (val) {
+ case LP55XX_ENGINE_1:
+ case LP55XX_ENGINE_2:
+ case LP55XX_ENGINE_3:
+ mutex_lock(&chip->lock);
+ chip->engine_idx = val;
+ ret = lp55xx_request_firmware(chip);
+ mutex_unlock(&chip->lock);
+ break;
+ default:
+ dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
+ return -EINVAL;
+ }
+
+ if (ret) {
+ dev_err(dev, "request firmware err: %d\n", ret);
+ return ret;
+ }
+
+ return len;
+}
+
+static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
+{
+ if (chip->cfg->run_engine)
+ chip->cfg->run_engine(chip, start);
+}
+
+static ssize_t lp55xx_store_engine_run(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+ unsigned long val;
+
+ if (kstrtoul(buf, 0, &val))
+ return -EINVAL;
+
+ /* run or stop the selected engine */
+
+ if (val <= 0) {
+ lp55xx_run_engine(chip, false);
+ return len;
+ }
+
+ mutex_lock(&chip->lock);
+ lp55xx_run_engine(chip, true);
+ mutex_unlock(&chip->lock);
+
+ return len;
+}
+
+static DEVICE_ATTR(select_engine, S_IRUGO | S_IWUSR,
+ lp55xx_show_engine_select, lp55xx_store_engine_select);
+static DEVICE_ATTR(run_engine, S_IWUSR, NULL, lp55xx_store_engine_run);
+
+static struct attribute *lp55xx_engine_attributes[] = {
+ &dev_attr_select_engine.attr,
+ &dev_attr_run_engine.attr,
+ NULL,
+};
+
+static const struct attribute_group lp55xx_engine_attr_group = {
+ .attrs = lp55xx_engine_attributes,
+};
+
+int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
+{
+ return i2c_smbus_write_byte_data(chip->cl, reg, val);
+}
+EXPORT_SYMBOL_GPL(lp55xx_write);
+
+int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
+{
+ s32 ret;
+
+ ret = i2c_smbus_read_byte_data(chip->cl, reg);
+ if (ret < 0)
+ return ret;
+
+ *val = ret;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(lp55xx_read);
+
+int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
+{
+ int ret;
+ u8 tmp;
+
+ ret = lp55xx_read(chip, reg, &tmp);
+ if (ret)
+ return ret;
+
+ tmp &= ~mask;
+ tmp |= val & mask;
+
+ return lp55xx_write(chip, reg, tmp);
+}
+EXPORT_SYMBOL_GPL(lp55xx_update_bits);
+
+bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
+{
+ struct clk *clk;
+ int err;
+
+ clk = devm_clk_get(&chip->cl->dev, "32k_clk");
+ if (IS_ERR(clk))
+ goto use_internal_clk;
+
+ err = clk_prepare_enable(clk);
+ if (err)
+ goto use_internal_clk;
+
+ if (clk_get_rate(clk) != LP55XX_CLK_32K) {
+ clk_disable_unprepare(clk);
+ goto use_internal_clk;
+ }
+
+ dev_info(&chip->cl->dev, "%dHz external clock used\n", LP55XX_CLK_32K);
+
+ chip->clk = clk;
+ return true;
+
+use_internal_clk:
+ dev_info(&chip->cl->dev, "internal clock used\n");
+ return false;
+}
+EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
+
+int lp55xx_init_device(struct lp55xx_chip *chip)
+{
+ struct lp55xx_platform_data *pdata;
+ struct lp55xx_device_config *cfg;
+ struct device *dev = &chip->cl->dev;
+ int ret = 0;
+
+ WARN_ON(!chip);
+
+ pdata = chip->pdata;
+ cfg = chip->cfg;
+
+ if (!pdata || !cfg)
+ return -EINVAL;
+
+ if (gpio_is_valid(pdata->enable_gpio)) {
+ ret = devm_gpio_request_one(dev, pdata->enable_gpio,
+ GPIOF_DIR_OUT, "lp5523_enable");
+ if (ret < 0) {
+ dev_err(dev, "could not acquire enable gpio (err=%d)\n",
+ ret);
+ goto err;
+ }
+
+ gpio_set_value(pdata->enable_gpio, 0);
+ usleep_range(1000, 2000); /* Keep enable down at least 1ms */
+ gpio_set_value(pdata->enable_gpio, 1);
+ usleep_range(1000, 2000); /* 500us abs min. */
+ }
+
+ lp55xx_reset_device(chip);
+
+ /*
+ * Exact value is not available. 10 - 20ms
+ * appears to be enough for reset.
+ */
+ usleep_range(10000, 20000);
+
+ ret = lp55xx_detect_device(chip);
+ if (ret) {
+ dev_err(dev, "device detection err: %d\n", ret);
+ goto err;
+ }
+
+ /* chip specific initialization */
+ ret = lp55xx_post_init_device(chip);
+ if (ret) {
+ dev_err(dev, "post init device err: %d\n", ret);
+ goto err_post_init;
+ }
+
+ return 0;
+
+err_post_init:
+ lp55xx_deinit_device(chip);
+err:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(lp55xx_init_device);
+
+void lp55xx_deinit_device(struct lp55xx_chip *chip)
+{
+ struct lp55xx_platform_data *pdata = chip->pdata;
+
+ if (chip->clk)
+ clk_disable_unprepare(chip->clk);
+
+ if (gpio_is_valid(pdata->enable_gpio))
+ gpio_set_value(pdata->enable_gpio, 0);
+}
+EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
+
+int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
+{
+ struct lp55xx_platform_data *pdata = chip->pdata;
+ struct lp55xx_device_config *cfg = chip->cfg;
+ int num_channels = pdata->num_channels;
+ struct lp55xx_led *each;
+ u8 led_current;
+ int ret;
+ int i;
+
+ if (!cfg->brightness_work_fn) {
+ dev_err(&chip->cl->dev, "empty brightness configuration\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < num_channels; i++) {
+
+ /* do not initialize channels that are not connected */
+ if (pdata->led_config[i].led_current == 0)
+ continue;
+
+ led_current = pdata->led_config[i].led_current;
+ each = led + i;
+ ret = lp55xx_init_led(each, chip, i);
+ if (ret)
+ goto err_init_led;
+
+ INIT_WORK(&each->brightness_work, cfg->brightness_work_fn);
+
+ chip->num_leds++;
+ each->chip = chip;
+
+ /* setting led current at each channel */
+ if (cfg->set_led_current)
+ cfg->set_led_current(each, led_current);
+ }
+
+ return 0;
+
+err_init_led:
+ lp55xx_unregister_leds(led, chip);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(lp55xx_register_leds);
+
+void lp55xx_unregister_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
+{
+ int i;
+ struct lp55xx_led *each;
+
+ for (i = 0; i < chip->num_leds; i++) {
+ each = led + i;
+ led_classdev_unregister(&each->cdev);
+ flush_work(&each->brightness_work);
+ }
+}
+EXPORT_SYMBOL_GPL(lp55xx_unregister_leds);
+
+int lp55xx_register_sysfs(struct lp55xx_chip *chip)
+{
+ struct device *dev = &chip->cl->dev;
+ struct lp55xx_device_config *cfg = chip->cfg;
+ int ret;
+
+ if (!cfg->run_engine || !cfg->firmware_cb)
+ goto dev_specific_attrs;
+
+ ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
+ if (ret)
+ return ret;
+
+dev_specific_attrs:
+ return cfg->dev_attr_group ?
+ sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
+}
+EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
+
+void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
+{
+ struct device *dev = &chip->cl->dev;
+ struct lp55xx_device_config *cfg = chip->cfg;
+
+ if (cfg->dev_attr_group)
+ sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
+
+ sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
+}
+EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
+
+int lp55xx_of_populate_pdata(struct device *dev, struct device_node *np)
+{
+ struct device_node *child;
+ struct lp55xx_platform_data *pdata;
+ struct lp55xx_led_config *cfg;
+ int num_channels;
+ int i = 0;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ num_channels = of_get_child_count(np);
+ if (num_channels == 0) {
+ dev_err(dev, "no LED channels\n");
+ return -EINVAL;
+ }
+
+ cfg = devm_kzalloc(dev, sizeof(*cfg) * num_channels, GFP_KERNEL);
+ if (!cfg)
+ return -ENOMEM;
+
+ pdata->led_config = &cfg[0];
+ pdata->num_channels = num_channels;
+
+ for_each_child_of_node(np, child) {
+ cfg[i].chan_nr = i;
+
+ of_property_read_string(child, "chan-name", &cfg[i].name);
+ of_property_read_u8(child, "led-cur", &cfg[i].led_current);
+ of_property_read_u8(child, "max-cur", &cfg[i].max_current);
+ cfg[i].default_trigger =
+ of_get_property(child, "linux,default-trigger", NULL);
+
+ i++;
+ }
+
+ of_property_read_string(np, "label", &pdata->label);
+ of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
+
+ pdata->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0);
+
+ /* LP8501 specific */
+ of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
+
+ dev->platform_data = pdata;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
+
+MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
+MODULE_DESCRIPTION("LP55xx Common Driver");
+MODULE_LICENSE("GPL");