diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/leds/leds-lp5521.c |
Initial import
Diffstat (limited to 'drivers/leds/leds-lp5521.c')
-rw-r--r-- | drivers/leds/leds-lp5521.c | 617 |
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"); |