diff options
Diffstat (limited to 'drivers/leds/leds-lp5523.c')
| -rw-r--r-- | drivers/leds/leds-lp5523.c | 517 |
1 files changed, 517 insertions, 0 deletions
diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c new file mode 100644 index 00000000..229f7340 --- /dev/null +++ b/drivers/leds/leds-lp5523.c @@ -0,0 +1,517 @@ +/* + * 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"); |