--- /dev/null
+/*
+ * TI LP8501 9 channel LED Driver
+ *
+ * Copyright (C) 2013 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.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_data/leds-lp55xx.h>
+#include <linux/slab.h>
+
+#include "leds-lp55xx-common.h"
+
+#define LP8501_PROGRAM_LENGTH 32
+#define LP8501_MAX_LEDS 9
+
+/* Registers */
+#define LP8501_REG_ENABLE 0x00
+#define LP8501_ENABLE BIT(6)
+#define LP8501_EXEC_M 0x3F
+#define LP8501_EXEC_ENG1_M 0x30
+#define LP8501_EXEC_ENG2_M 0x0C
+#define LP8501_EXEC_ENG3_M 0x03
+#define LP8501_RUN_ENG1 0x20
+#define LP8501_RUN_ENG2 0x08
+#define LP8501_RUN_ENG3 0x02
+
+#define LP8501_REG_OP_MODE 0x01
+#define LP8501_MODE_ENG1_M 0x30
+#define LP8501_MODE_ENG2_M 0x0C
+#define LP8501_MODE_ENG3_M 0x03
+#define LP8501_LOAD_ENG1 0x10
+#define LP8501_LOAD_ENG2 0x04
+#define LP8501_LOAD_ENG3 0x01
+
+#define LP8501_REG_PWR_CONFIG 0x05
+#define LP8501_PWR_CONFIG_M 0x03
+
+#define LP8501_REG_LED_PWM_BASE 0x16
+
+#define LP8501_REG_LED_CURRENT_BASE 0x26
+
+#define LP8501_REG_CONFIG 0x36
+#define LP8501_PWM_PSAVE BIT(7)
+#define LP8501_AUTO_INC BIT(6)
+#define LP8501_PWR_SAVE BIT(5)
+#define LP8501_CP_AUTO 0x18
+#define LP8501_INT_CLK BIT(0)
+#define LP8501_DEFAULT_CFG \
+ (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO)
+
+#define LP8501_REG_RESET 0x3D
+#define LP8501_RESET 0xFF
+
+#define LP8501_REG_PROG_PAGE_SEL 0x4F
+#define LP8501_PAGE_ENG1 0
+#define LP8501_PAGE_ENG2 1
+#define LP8501_PAGE_ENG3 2
+
+#define LP8501_REG_PROG_MEM 0x50
+
+#define LP8501_ENG1_IS_LOADING(mode) \
+ ((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1)
+#define LP8501_ENG2_IS_LOADING(mode) \
+ ((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2)
+#define LP8501_ENG3_IS_LOADING(mode) \
+ ((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3)
+
+static inline void lp8501_wait_opmode_done(void)
+{
+ usleep_range(1000, 2000);
+}
+
+static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current)
+{
+ led->led_current = led_current;
+ lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr,
+ led_current);
+}
+
+static int lp8501_post_init_device(struct lp55xx_chip *chip)
+{
+ int ret;
+ u8 val = LP8501_DEFAULT_CFG;
+
+ ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE);
+ if (ret)
+ return ret;
+
+ /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
+ usleep_range(1000, 2000);
+
+ if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT)
+ val |= LP8501_INT_CLK;
+
+ ret = lp55xx_write(chip, LP8501_REG_CONFIG, val);
+ if (ret)
+ return ret;
+
+ /* Power selection for each output */
+ return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG,
+ LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel);
+}
+
+static void lp8501_load_engine(struct lp55xx_chip *chip)
+{
+ enum lp55xx_engine_index idx = chip->engine_idx;
+ u8 mask[] = {
+ [LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M,
+ [LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M,
+ [LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M,
+ };
+
+ u8 val[] = {
+ [LP55XX_ENGINE_1] = LP8501_LOAD_ENG1,
+ [LP55XX_ENGINE_2] = LP8501_LOAD_ENG2,
+ [LP55XX_ENGINE_3] = LP8501_LOAD_ENG3,
+ };
+
+ u8 page_sel[] = {
+ [LP55XX_ENGINE_1] = LP8501_PAGE_ENG1,
+ [LP55XX_ENGINE_2] = LP8501_PAGE_ENG2,
+ [LP55XX_ENGINE_3] = LP8501_PAGE_ENG3,
+ };
+
+ lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]);
+
+ lp8501_wait_opmode_done();
+
+ lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]);
+}
+
+static void lp8501_stop_engine(struct lp55xx_chip *chip)
+{
+ lp55xx_write(chip, LP8501_REG_OP_MODE, 0);
+ lp8501_wait_opmode_done();
+}
+
+static void lp8501_turn_off_channels(struct lp55xx_chip *chip)
+{
+ int i;
+
+ for (i = 0; i < LP8501_MAX_LEDS; i++)
+ lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0);
+}
+
+static void lp8501_run_engine(struct lp55xx_chip *chip, bool start)
+{
+ int ret;
+ u8 mode;
+ u8 exec;
+
+ /* stop engine */
+ if (!start) {
+ lp8501_stop_engine(chip);
+ lp8501_turn_off_channels(chip);
+ return;
+ }
+
+ /*
+ * To run the engine,
+ * operation mode and enable register should updated at the same time
+ */
+
+ ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode);
+ if (ret)
+ return;
+
+ ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec);
+ if (ret)
+ return;
+
+ /* change operation mode to RUN only when each engine is loading */
+ if (LP8501_ENG1_IS_LOADING(mode)) {
+ mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1;
+ exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1;
+ }
+
+ if (LP8501_ENG2_IS_LOADING(mode)) {
+ mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2;
+ exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2;
+ }
+
+ if (LP8501_ENG3_IS_LOADING(mode)) {
+ mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3;
+ exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3;
+ }
+
+ lp55xx_write(chip, LP8501_REG_OP_MODE, mode);
+ lp8501_wait_opmode_done();
+
+ lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec);
+}
+
+static int lp8501_update_program_memory(struct lp55xx_chip *chip,
+ const u8 *data, size_t size)
+{
+ u8 pattern[LP8501_PROGRAM_LENGTH] = {0};
+ unsigned cmd;
+ char c[3];
+ int update_size;
+ int nrchars;
+ int offset = 0;
+ int ret;
+ int i;
+
+ /* clear program memory before updating */
+ for (i = 0; i < LP8501_PROGRAM_LENGTH; i++)
+ lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0);
+
+ i = 0;
+ while ((offset < size - 1) && (i < LP8501_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;
+
+ update_size = i;
+ for (i = 0; i < update_size; i++)
+ lp55xx_write(chip, LP8501_REG_PROG_MEM + i, pattern[i]);
+
+ return 0;
+
+err:
+ dev_err(&chip->cl->dev, "wrong pattern format\n");
+ return -EINVAL;
+}
+
+static void lp8501_firmware_loaded(struct lp55xx_chip *chip)
+{
+ const struct firmware *fw = chip->fw;
+
+ if (fw->size > LP8501_PROGRAM_LENGTH) {
+ dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
+ fw->size);
+ return;
+ }
+
+ /*
+ * Program memory sequence
+ * 1) set engine mode to "LOAD"
+ * 2) write firmware data into program memory
+ */
+
+ lp8501_load_engine(chip);
+ lp8501_update_program_memory(chip, fw->data, fw->size);
+}
+
+static void lp8501_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, LP8501_REG_LED_PWM_BASE + led->chan_nr,
+ led->brightness);
+ mutex_unlock(&chip->lock);
+}
+
+/* Chip specific configurations */
+static struct lp55xx_device_config lp8501_cfg = {
+ .reset = {
+ .addr = LP8501_REG_RESET,
+ .val = LP8501_RESET,
+ },
+ .enable = {
+ .addr = LP8501_REG_ENABLE,
+ .val = LP8501_ENABLE,
+ },
+ .max_channel = LP8501_MAX_LEDS,
+ .post_init_device = lp8501_post_init_device,
+ .brightness_work_fn = lp8501_led_brightness_work,
+ .set_led_current = lp8501_set_led_current,
+ .firmware_cb = lp8501_firmware_loaded,
+ .run_engine = lp8501_run_engine,
+};
+
+static int lp8501_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 = &lp8501_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 lp8501_remove(struct i2c_client *client)
+{
+ struct lp55xx_led *led = i2c_get_clientdata(client);
+ struct lp55xx_chip *chip = led->chip;
+
+ lp8501_stop_engine(chip);
+ lp55xx_unregister_sysfs(chip);
+ lp55xx_unregister_leds(led, chip);
+ lp55xx_deinit_device(chip);
+
+ return 0;
+}
+
+static const struct i2c_device_id lp8501_id[] = {
+ { "lp8501", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lp8501_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_lp8501_leds_match[] = {
+ { .compatible = "ti,lp8501", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_lp8501_leds_match);
+#endif
+
+static struct i2c_driver lp8501_driver = {
+ .driver = {
+ .name = "lp8501",
+ .of_match_table = of_match_ptr(of_lp8501_leds_match),
+ },
+ .probe = lp8501_probe,
+ .remove = lp8501_remove,
+ .id_table = lp8501_id,
+};
+
+module_i2c_driver(lp8501_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff