/* * lp5523.c - LP5523 LED 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/init.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 "leds-lp55xx-common.h" #define LP5523_PROGRAM_LENGTH 32 #define LP5523_MAX_LEDS 9 /* Registers */ #define LP5523_REG_ENABLE 0x00 #define LP5523_REG_OP_MODE 0x01 #define LP5523_REG_ENABLE_LEDS_MSB 0x04 #define LP5523_REG_ENABLE_LEDS_LSB 0x05 #define LP5523_REG_LED_PWM_BASE 0x16 #define LP5523_REG_LED_CURRENT_BASE 0x26 #define LP5523_REG_CONFIG 0x36 #define LP5523_REG_STATUS 0x3A #define LP5523_REG_RESET 0x3D #define LP5523_REG_LED_TEST_CTRL 0x41 #define LP5523_REG_LED_TEST_ADC 0x42 #define LP5523_REG_PROG_PAGE_SEL 0x4F #define LP5523_REG_PROG_MEM 0x50 /* Bit description in registers */ #define LP5523_ENABLE 0x40 #define LP5523_AUTO_INC 0x40 #define LP5523_PWR_SAVE 0x20 #define LP5523_PWM_PWR_SAVE 0x04 #define LP5523_CP_AUTO 0x18 #define LP5523_AUTO_CLK 0x02 #define LP5523_EN_LEDTEST 0x80 #define LP5523_LEDTEST_DONE 0x80 #define LP5523_RESET 0xFF #define LP5523_ADC_SHORTCIRC_LIM 80 #define LP5523_EXT_CLK_USED 0x08 /* Memory Page Selection */ #define LP5523_PAGE_ENG1 0 #define LP5523_PAGE_ENG2 1 #define LP5523_PAGE_ENG3 2 /* Program Memory Operations */ #define LP5523_MODE_ENG1_M 0x30 /* Operation Mode Register */ #define LP5523_MODE_ENG2_M 0x0C #define LP5523_MODE_ENG3_M 0x03 #define LP5523_LOAD_ENG1 0x10 #define LP5523_LOAD_ENG2 0x04 #define LP5523_LOAD_ENG3 0x01 #define LP5523_ENG1_IS_LOADING(mode) \ ((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1) #define LP5523_ENG2_IS_LOADING(mode) \ ((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2) #define LP5523_ENG3_IS_LOADING(mode) \ ((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3) #define LP5523_EXEC_ENG1_M 0x30 /* Enable Register */ #define LP5523_EXEC_ENG2_M 0x0C #define LP5523_EXEC_ENG3_M 0x03 #define LP5523_EXEC_M 0x3F #define LP5523_RUN_ENG1 0x20 #define LP5523_RUN_ENG2 0x08 #define LP5523_RUN_ENG3 0x02 enum lp5523_chip_id { LP5523, LP55231, }; static inline void lp5523_wait_opmode_done(void) { usleep_range(1000, 2000); } static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current) { led->led_current = led_current; lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr, led_current); } static int lp5523_post_init_device(struct lp55xx_chip *chip) { int ret; ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE); if (ret) return ret; /* Chip startup time is 500 us, 1 - 2 ms gives some margin */ usleep_range(1000, 2000); ret = lp55xx_write(chip, LP5523_REG_CONFIG, LP5523_AUTO_INC | LP5523_PWR_SAVE | LP5523_CP_AUTO | LP5523_AUTO_CLK | LP5523_PWM_PWR_SAVE); if (ret) return ret; /* turn on all leds */ ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01); if (ret) return ret; return lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff); } static void lp5523_load_engine(struct lp55xx_chip *chip) { enum lp55xx_engine_index idx = chip->engine_idx; u8 mask[] = { [LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M, [LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M, [LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M, }; u8 val[] = { [LP55XX_ENGINE_1] = LP5523_LOAD_ENG1, [LP55XX_ENGINE_2] = LP5523_LOAD_ENG2, [LP55XX_ENGINE_3] = LP5523_LOAD_ENG3, }; u8 page_sel[] = { [LP55XX_ENGINE_1] = LP5523_PAGE_ENG1, [LP55XX_ENGINE_2] = LP5523_PAGE_ENG2, [LP55XX_ENGINE_3] = LP5523_PAGE_ENG3, }; lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]); lp5523_wait_opmode_done(); lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]); } static void lp5523_stop_engine(struct lp55xx_chip *chip) { lp55xx_write(chip, LP5523_REG_OP_MODE, 0); lp5523_wait_opmode_done(); } static void lp5523_turn_off_channels(struct lp55xx_chip *chip) { int i; for (i = 0; i < LP5523_MAX_LEDS; i++) lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0); } static void lp5523_run_engine(struct lp55xx_chip *chip, bool start) { int ret; u8 mode; u8 exec; /* stop engine */ if (!start) { lp5523_stop_engine(chip); lp5523_turn_off_channels(chip); return; } /* * To run the engine, * operation mode and enable register should updated at the same time */ ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode); if (ret) return; ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec); if (ret) return; /* change operation mode to RUN only when each engine is loading */ if (LP5523_ENG1_IS_LOADING(mode)) { mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1; exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1; } if (LP5523_ENG2_IS_LOADING(mode)) { mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2; exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2; } if (LP5523_ENG3_IS_LOADING(mode)) { mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3; exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3; } lp55xx_write(chip, LP5523_REG_OP_MODE, mode); lp5523_wait_opmode_done(); lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec); } static int lp5523_update_program_memory(struct lp55xx_chip *chip, const u8 *data, size_t size) { u8 pattern[LP5523_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 < LP5523_PROGRAM_LENGTH; i++) lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0); i = 0; while ((offset < size - 1) && (i < LP5523_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, LP5523_REG_PROG_MEM + i, pattern[i]); return 0; err: dev_err(&chip->cl->dev, "wrong pattern format\n"); return -EINVAL; } static void lp5523_firmware_loaded(struct lp55xx_chip *chip) { const struct firmware *fw = chip->fw; if (fw->size > LP5523_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 */ lp5523_load_engine(chip); lp5523_update_program_memory(chip, fw->data, fw->size); } static ssize_t lp5523_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; struct lp55xx_platform_data *pdata = chip->pdata; int i, ret, pos = 0; u8 status, adc, vdd; mutex_lock(&chip->lock); ret = lp55xx_read(chip, LP5523_REG_STATUS, &status); if (ret < 0) goto fail; /* Check that ext clock is really in use if requested */ if (pdata->clock_mode == LP55XX_CLOCK_EXT) { if ((status & LP5523_EXT_CLK_USED) == 0) goto fail; } /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */ lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16); usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */ ret = lp55xx_read(chip, LP5523_REG_STATUS, &status); if (ret < 0) goto fail; if (!(status & LP5523_LEDTEST_DONE)) usleep_range(3000, 6000); /* Was not ready. Wait little bit */ ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd); if (ret < 0) goto fail; vdd--; /* There may be some fluctuation in measurement */ for (i = 0; i < LP5523_MAX_LEDS; i++) { /* Skip non-existing channels */ if (pdata->led_config[i].led_current == 0) continue; /* Set default current */ lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i, pdata->led_config[i].led_current); lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff); /* let current stabilize 2 - 4ms before measurements start */ usleep_range(2000, 4000); lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | i); /* ADC conversion time is 2.7 ms typically */ usleep_range(3000, 6000); ret = lp55xx_read(chip, LP5523_REG_STATUS, &status); if (ret < 0) goto fail; if (!(status & LP5523_LEDTEST_DONE)) usleep_range(3000, 6000);/* Was not ready. Wait. */ ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc); if (ret < 0) goto fail; if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM) pos += sprintf(buf + pos, "LED %d FAIL\n", i); lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00); /* Restore current */ lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i, led->led_current); led++; } if (pos == 0) pos = sprintf(buf, "OK\n"); goto release_lock; fail: pos = sprintf(buf, "FAIL\n"); release_lock: mutex_unlock(&chip->lock); return pos; } static void lp5523_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, LP5523_REG_LED_PWM_BASE + led->chan_nr, led->brightness); mutex_unlock(&chip->lock); } static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL); static struct attribute *lp5523_attributes[] = { &dev_attr_selftest.attr, NULL, }; static const struct attribute_group lp5523_group = { .attrs = lp5523_attributes, }; /* Chip specific configurations */ static struct lp55xx_device_config lp5523_cfg = { .reset = { .addr = LP5523_REG_RESET, .val = LP5523_RESET, }, .enable = { .addr = LP5523_REG_ENABLE, .val = LP5523_ENABLE, }, .max_channel = LP5523_MAX_LEDS, .post_init_device = lp5523_post_init_device, .brightness_work_fn = lp5523_led_brightness_work, .set_led_current = lp5523_set_led_current, .firmware_cb = lp5523_firmware_loaded, .run_engine = lp5523_run_engine, .dev_attr_group = &lp5523_group, }; static int lp5523_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 = client->dev.platform_data; if (!pdata) { dev_err(&client->dev, "no platform data\n"); return -EINVAL; } 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 = &lp5523_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 lp5523_remove(struct i2c_client *client) { struct lp55xx_led *led = i2c_get_clientdata(client); struct lp55xx_chip *chip = led->chip; lp5523_stop_engine(chip); lp55xx_unregister_sysfs(chip); lp55xx_unregister_leds(led, chip); lp55xx_deinit_device(chip); return 0; } static const struct i2c_device_id lp5523_id[] = { { "lp5523", LP5523 }, { "lp55231", LP55231 }, { } }; MODULE_DEVICE_TABLE(i2c, lp5523_id); static struct i2c_driver lp5523_driver = { .driver = { .name = "lp5523x", }, .probe = lp5523_probe, .remove = lp5523_remove, .id_table = lp5523_id, }; module_i2c_driver(lp5523_driver); MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>"); MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); MODULE_DESCRIPTION("LP5523 LED engine"); MODULE_LICENSE("GPL");