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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/leds/leds-lp5521.c
Initial import
Diffstat (limited to 'drivers/leds/leds-lp5521.c')
-rw-r--r--drivers/leds/leds-lp5521.c617
1 files changed, 617 insertions, 0 deletions
diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
new file mode 100644
index 000000000..8ca197af2
--- /dev/null
+++ b/drivers/leds/leds-lp5521.c
@@ -0,0 +1,617 @@
+/*
+ * LP5521 LED chip driver.
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ * Copyright (C) 2012 Texas Instruments
+ *
+ * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_data/leds-lp55xx.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#include "leds-lp55xx-common.h"
+
+#define LP5521_PROGRAM_LENGTH 32
+#define LP5521_MAX_LEDS 3
+#define LP5521_CMD_DIRECT 0x3F
+
+/* Registers */
+#define LP5521_REG_ENABLE 0x00
+#define LP5521_REG_OP_MODE 0x01
+#define LP5521_REG_R_PWM 0x02
+#define LP5521_REG_G_PWM 0x03
+#define LP5521_REG_B_PWM 0x04
+#define LP5521_REG_R_CURRENT 0x05
+#define LP5521_REG_G_CURRENT 0x06
+#define LP5521_REG_B_CURRENT 0x07
+#define LP5521_REG_CONFIG 0x08
+#define LP5521_REG_STATUS 0x0C
+#define LP5521_REG_RESET 0x0D
+#define LP5521_REG_R_PROG_MEM 0x10
+#define LP5521_REG_G_PROG_MEM 0x30
+#define LP5521_REG_B_PROG_MEM 0x50
+
+/* Base register to set LED current */
+#define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
+/* Base register to set the brightness */
+#define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
+
+/* Bits in ENABLE register */
+#define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
+#define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
+#define LP5521_EXEC_RUN 0x2A
+#define LP5521_ENABLE_DEFAULT \
+ (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
+#define LP5521_ENABLE_RUN_PROGRAM \
+ (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
+
+/* CONFIG register */
+#define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
+#define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
+#define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
+#define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
+#define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
+#define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
+#define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
+#define LP5521_CLK_INT 0x01 /* Internal clock */
+#define LP5521_DEFAULT_CFG \
+ (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
+
+/* Status */
+#define LP5521_EXT_CLK_USED 0x08
+
+/* default R channel current register value */
+#define LP5521_REG_R_CURR_DEFAULT 0xAF
+
+/* Reset register value */
+#define LP5521_RESET 0xFF
+
+/* Program Memory Operations */
+#define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
+#define LP5521_MODE_G_M 0x0C
+#define LP5521_MODE_B_M 0x03
+#define LP5521_LOAD_R 0x10
+#define LP5521_LOAD_G 0x04
+#define LP5521_LOAD_B 0x01
+
+#define LP5521_R_IS_LOADING(mode) \
+ ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
+#define LP5521_G_IS_LOADING(mode) \
+ ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
+#define LP5521_B_IS_LOADING(mode) \
+ ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
+
+#define LP5521_EXEC_R_M 0x30 /* Enable Register */
+#define LP5521_EXEC_G_M 0x0C
+#define LP5521_EXEC_B_M 0x03
+#define LP5521_EXEC_M 0x3F
+#define LP5521_RUN_R 0x20
+#define LP5521_RUN_G 0x08
+#define LP5521_RUN_B 0x02
+
+static inline void lp5521_wait_opmode_done(void)
+{
+ /* operation mode change needs to be longer than 153 us */
+ usleep_range(200, 300);
+}
+
+static inline void lp5521_wait_enable_done(void)
+{
+ /* it takes more 488 us to update ENABLE register */
+ usleep_range(500, 600);
+}
+
+static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
+{
+ led->led_current = led_current;
+ lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
+ led_current);
+}
+
+static void lp5521_load_engine(struct lp55xx_chip *chip)
+{
+ enum lp55xx_engine_index idx = chip->engine_idx;
+ u8 mask[] = {
+ [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
+ [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
+ [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
+ };
+
+ u8 val[] = {
+ [LP55XX_ENGINE_1] = LP5521_LOAD_R,
+ [LP55XX_ENGINE_2] = LP5521_LOAD_G,
+ [LP55XX_ENGINE_3] = LP5521_LOAD_B,
+ };
+
+ lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
+
+ lp5521_wait_opmode_done();
+}
+
+static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
+{
+ lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
+ lp5521_wait_opmode_done();
+}
+
+static void lp5521_stop_engine(struct lp55xx_chip *chip)
+{
+ enum lp55xx_engine_index idx = chip->engine_idx;
+ u8 mask[] = {
+ [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
+ [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
+ [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
+ };
+
+ lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
+
+ lp5521_wait_opmode_done();
+}
+
+static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
+{
+ int ret;
+ u8 mode;
+ u8 exec;
+
+ /* stop engine */
+ if (!start) {
+ lp5521_stop_engine(chip);
+ lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
+ lp5521_wait_opmode_done();
+ return;
+ }
+
+ /*
+ * To run the engine,
+ * operation mode and enable register should updated at the same time
+ */
+
+ ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
+ if (ret)
+ return;
+
+ ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
+ if (ret)
+ return;
+
+ /* change operation mode to RUN only when each engine is loading */
+ if (LP5521_R_IS_LOADING(mode)) {
+ mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
+ exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
+ }
+
+ if (LP5521_G_IS_LOADING(mode)) {
+ mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
+ exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
+ }
+
+ if (LP5521_B_IS_LOADING(mode)) {
+ mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
+ exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
+ }
+
+ lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
+ lp5521_wait_opmode_done();
+
+ lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
+ lp5521_wait_enable_done();
+}
+
+static int lp5521_update_program_memory(struct lp55xx_chip *chip,
+ const u8 *data, size_t size)
+{
+ enum lp55xx_engine_index idx = chip->engine_idx;
+ u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
+ u8 addr[] = {
+ [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
+ [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
+ [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
+ };
+ unsigned cmd;
+ char c[3];
+ int nrchars;
+ int ret;
+ int offset = 0;
+ int i = 0;
+
+ while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
+ /* separate sscanfs because length is working only for %s */
+ ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
+ if (ret != 1)
+ goto err;
+
+ ret = sscanf(c, "%2x", &cmd);
+ if (ret != 1)
+ goto err;
+
+ pattern[i] = (u8)cmd;
+ offset += nrchars;
+ i++;
+ }
+
+ /* Each instruction is 16bit long. Check that length is even */
+ if (i % 2)
+ goto err;
+
+ for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
+ ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
+ if (ret)
+ return -EINVAL;
+ }
+
+ return size;
+
+err:
+ dev_err(&chip->cl->dev, "wrong pattern format\n");
+ return -EINVAL;
+}
+
+static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
+{
+ const struct firmware *fw = chip->fw;
+
+ if (fw->size > LP5521_PROGRAM_LENGTH) {
+ dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
+ fw->size);
+ return;
+ }
+
+ /*
+ * Program momery sequence
+ * 1) set engine mode to "LOAD"
+ * 2) write firmware data into program memory
+ */
+
+ lp5521_load_engine(chip);
+ lp5521_update_program_memory(chip, fw->data, fw->size);
+}
+
+static int lp5521_post_init_device(struct lp55xx_chip *chip)
+{
+ int ret;
+ u8 val;
+
+ /*
+ * Make sure that the chip is reset by reading back the r channel
+ * current reg. This is dummy read is required on some platforms -
+ * otherwise further access to the R G B channels in the
+ * LP5521_REG_ENABLE register will not have any effect - strange!
+ */
+ ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
+ if (ret) {
+ dev_err(&chip->cl->dev, "error in resetting chip\n");
+ return ret;
+ }
+ if (val != LP5521_REG_R_CURR_DEFAULT) {
+ dev_err(&chip->cl->dev,
+ "unexpected data in register (expected 0x%x got 0x%x)\n",
+ LP5521_REG_R_CURR_DEFAULT, val);
+ ret = -EINVAL;
+ return ret;
+ }
+ usleep_range(10000, 20000);
+
+ /* Set all PWMs to direct control mode */
+ ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
+
+ /* Update configuration for the clock setting */
+ val = LP5521_DEFAULT_CFG;
+ if (!lp55xx_is_extclk_used(chip))
+ val |= LP5521_CLK_INT;
+
+ ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
+ if (ret)
+ return ret;
+
+ /* Initialize all channels PWM to zero -> leds off */
+ lp55xx_write(chip, LP5521_REG_R_PWM, 0);
+ lp55xx_write(chip, LP5521_REG_G_PWM, 0);
+ lp55xx_write(chip, LP5521_REG_B_PWM, 0);
+
+ /* Set engines are set to run state when OP_MODE enables engines */
+ ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
+ if (ret)
+ return ret;
+
+ lp5521_wait_enable_done();
+
+ return 0;
+}
+
+static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
+{
+ struct lp55xx_platform_data *pdata = chip->pdata;
+ int ret;
+ u8 status;
+
+ ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (pdata->clock_mode != LP55XX_CLOCK_EXT)
+ return 0;
+
+ /* Check that ext clock is really in use if requested */
+ if ((status & LP5521_EXT_CLK_USED) == 0)
+ return -EIO;
+
+ return 0;
+}
+
+static void lp5521_led_brightness_work(struct work_struct *work)
+{
+ struct lp55xx_led *led = container_of(work, struct lp55xx_led,
+ brightness_work);
+ struct lp55xx_chip *chip = led->chip;
+
+ mutex_lock(&chip->lock);
+ lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
+ led->brightness);
+ mutex_unlock(&chip->lock);
+}
+
+static ssize_t show_engine_mode(struct device *dev,
+ struct device_attribute *attr,
+ char *buf, int nr)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+ enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
+
+ switch (mode) {
+ case LP55XX_ENGINE_RUN:
+ return sprintf(buf, "run\n");
+ case LP55XX_ENGINE_LOAD:
+ return sprintf(buf, "load\n");
+ case LP55XX_ENGINE_DISABLED:
+ default:
+ return sprintf(buf, "disabled\n");
+ }
+}
+show_mode(1)
+show_mode(2)
+show_mode(3)
+
+static ssize_t store_engine_mode(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len, int nr)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+ struct lp55xx_engine *engine = &chip->engines[nr - 1];
+
+ mutex_lock(&chip->lock);
+
+ chip->engine_idx = nr;
+
+ if (!strncmp(buf, "run", 3)) {
+ lp5521_run_engine(chip, true);
+ engine->mode = LP55XX_ENGINE_RUN;
+ } else if (!strncmp(buf, "load", 4)) {
+ lp5521_stop_engine(chip);
+ lp5521_load_engine(chip);
+ engine->mode = LP55XX_ENGINE_LOAD;
+ } else if (!strncmp(buf, "disabled", 8)) {
+ lp5521_stop_engine(chip);
+ engine->mode = LP55XX_ENGINE_DISABLED;
+ }
+
+ mutex_unlock(&chip->lock);
+
+ return len;
+}
+store_mode(1)
+store_mode(2)
+store_mode(3)
+
+static ssize_t store_engine_load(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len, int nr)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+ struct lp55xx_chip *chip = led->chip;
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ chip->engine_idx = nr;
+ lp5521_load_engine(chip);
+ ret = lp5521_update_program_memory(chip, buf, len);
+
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+store_load(1)
+store_load(2)
+store_load(3)
+
+static ssize_t lp5521_selftest(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;
+ int ret;
+
+ mutex_lock(&chip->lock);
+ ret = lp5521_run_selftest(chip, buf);
+ mutex_unlock(&chip->lock);
+
+ return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
+}
+
+/* device attributes */
+static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
+static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
+static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
+static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
+static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
+static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
+static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
+
+static struct attribute *lp5521_attributes[] = {
+ &dev_attr_engine1_mode.attr,
+ &dev_attr_engine2_mode.attr,
+ &dev_attr_engine3_mode.attr,
+ &dev_attr_engine1_load.attr,
+ &dev_attr_engine2_load.attr,
+ &dev_attr_engine3_load.attr,
+ &dev_attr_selftest.attr,
+ NULL
+};
+
+static const struct attribute_group lp5521_group = {
+ .attrs = lp5521_attributes,
+};
+
+/* Chip specific configurations */
+static struct lp55xx_device_config lp5521_cfg = {
+ .reset = {
+ .addr = LP5521_REG_RESET,
+ .val = LP5521_RESET,
+ },
+ .enable = {
+ .addr = LP5521_REG_ENABLE,
+ .val = LP5521_ENABLE_DEFAULT,
+ },
+ .max_channel = LP5521_MAX_LEDS,
+ .post_init_device = lp5521_post_init_device,
+ .brightness_work_fn = lp5521_led_brightness_work,
+ .set_led_current = lp5521_set_led_current,
+ .firmware_cb = lp5521_firmware_loaded,
+ .run_engine = lp5521_run_engine,
+ .dev_attr_group = &lp5521_group,
+};
+
+static int lp5521_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct lp55xx_chip *chip;
+ struct lp55xx_led *led;
+ struct lp55xx_platform_data *pdata;
+ struct device_node *np = client->dev.of_node;
+
+ if (!dev_get_platdata(&client->dev)) {
+ if (np) {
+ ret = lp55xx_of_populate_pdata(&client->dev, np);
+ if (ret < 0)
+ return ret;
+ } else {
+ dev_err(&client->dev, "no platform data\n");
+ return -EINVAL;
+ }
+ }
+ pdata = dev_get_platdata(&client->dev);
+
+ chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ led = devm_kzalloc(&client->dev,
+ sizeof(*led) * pdata->num_channels, GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ chip->cl = client;
+ chip->pdata = pdata;
+ chip->cfg = &lp5521_cfg;
+
+ mutex_init(&chip->lock);
+
+ i2c_set_clientdata(client, led);
+
+ ret = lp55xx_init_device(chip);
+ if (ret)
+ goto err_init;
+
+ dev_info(&client->dev, "%s programmable led chip found\n", id->name);
+
+ ret = lp55xx_register_leds(led, chip);
+ if (ret)
+ goto err_register_leds;
+
+ ret = lp55xx_register_sysfs(chip);
+ if (ret) {
+ dev_err(&client->dev, "registering sysfs failed\n");
+ goto err_register_sysfs;
+ }
+
+ return 0;
+
+err_register_sysfs:
+ lp55xx_unregister_leds(led, chip);
+err_register_leds:
+ lp55xx_deinit_device(chip);
+err_init:
+ return ret;
+}
+
+static int lp5521_remove(struct i2c_client *client)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(client);
+ struct lp55xx_chip *chip = led->chip;
+
+ lp5521_stop_all_engines(chip);
+ lp55xx_unregister_sysfs(chip);
+ lp55xx_unregister_leds(led, chip);
+ lp55xx_deinit_device(chip);
+
+ return 0;
+}
+
+static const struct i2c_device_id lp5521_id[] = {
+ { "lp5521", 0 }, /* Three channel chip */
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lp5521_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_lp5521_leds_match[] = {
+ { .compatible = "national,lp5521", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
+#endif
+static struct i2c_driver lp5521_driver = {
+ .driver = {
+ .name = "lp5521",
+ .of_match_table = of_match_ptr(of_lp5521_leds_match),
+ },
+ .probe = lp5521_probe,
+ .remove = lp5521_remove,
+ .id_table = lp5521_id,
+};
+
+module_i2c_driver(lp5521_driver);
+
+MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
+MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
+MODULE_DESCRIPTION("LP5521 LED engine");
+MODULE_LICENSE("GPL v2");