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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * LP5521 LED chip driver.4 *5 * Copyright (C) 2010 Nokia Corporation6 * Copyright (C) 2012 Texas Instruments7 *8 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>9 * Milo(Woogyom) Kim <milo.kim@ti.com>10 */11 12#include <linux/cleanup.h>13#include <linux/delay.h>14#include <linux/firmware.h>15#include <linux/i2c.h>16#include <linux/leds.h>17#include <linux/module.h>18#include <linux/mutex.h>19#include <linux/platform_data/leds-lp55xx.h>20#include <linux/slab.h>21#include <linux/of.h>22 23#include "leds-lp55xx-common.h"24 25#define LP5521_MAX_LEDS 326#define LP5521_CMD_DIRECT 0x3F27 28/* Registers */29#define LP5521_REG_ENABLE 0x0030#define LP5521_REG_OP_MODE 0x0131#define LP5521_REG_R_PWM 0x0232#define LP5521_REG_G_PWM 0x0333#define LP5521_REG_B_PWM 0x0434#define LP5521_REG_R_CURRENT 0x0535#define LP5521_REG_G_CURRENT 0x0636#define LP5521_REG_B_CURRENT 0x0737#define LP5521_REG_CONFIG 0x0838#define LP5521_REG_STATUS 0x0C39#define LP5521_REG_RESET 0x0D40#define LP5521_REG_R_PROG_MEM 0x1041#define LP5521_REG_G_PROG_MEM 0x3042#define LP5521_REG_B_PROG_MEM 0x5043 44/* Base register to set LED current */45#define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT46/* Base register to set the brightness */47#define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM48 49/* Bits in ENABLE register */50#define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */51#define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */52#define LP5521_EXEC_RUN 0x2A53#define LP5521_ENABLE_DEFAULT \54 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)55#define LP5521_ENABLE_RUN_PROGRAM \56 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)57 58/* CONFIG register */59#define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */60#define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */61#define LP5521_CP_MODE_MASK 0x18 /* Charge pump mode */62#define LP5521_CP_MODE_SHIFT 363#define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */64#define LP5521_CLK_INT 0x01 /* Internal clock */65#define LP5521_DEFAULT_CFG (LP5521_PWM_HF | LP5521_PWRSAVE_EN)66 67/* Status */68#define LP5521_EXT_CLK_USED 0x0869 70/* default R channel current register value */71#define LP5521_REG_R_CURR_DEFAULT 0xAF72 73/* Reset register value */74#define LP5521_RESET 0xFF75 76static inline void lp5521_wait_opmode_done(void)77{78 /* operation mode change needs to be longer than 153 us */79 usleep_range(200, 300);80}81 82static inline void lp5521_wait_enable_done(void)83{84 /* it takes more 488 us to update ENABLE register */85 usleep_range(500, 600);86}87 88static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)89{90 int ret;91 92 /* stop engine */93 if (!start) {94 lp55xx_stop_engine(chip);95 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);96 lp5521_wait_opmode_done();97 return;98 }99 100 ret = lp55xx_run_engine_common(chip);101 if (!ret)102 lp5521_wait_enable_done();103}104 105static int lp5521_post_init_device(struct lp55xx_chip *chip)106{107 int ret;108 u8 val;109 110 /*111 * Make sure that the chip is reset by reading back the r channel112 * current reg. This is dummy read is required on some platforms -113 * otherwise further access to the R G B channels in the114 * LP5521_REG_ENABLE register will not have any effect - strange!115 */116 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);117 if (ret) {118 dev_err(&chip->cl->dev, "error in resetting chip\n");119 return ret;120 }121 if (val != LP5521_REG_R_CURR_DEFAULT) {122 dev_err(&chip->cl->dev,123 "unexpected data in register (expected 0x%x got 0x%x)\n",124 LP5521_REG_R_CURR_DEFAULT, val);125 ret = -EINVAL;126 return ret;127 }128 usleep_range(10000, 20000);129 130 /* Set all PWMs to direct control mode */131 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);132 if (ret)133 return ret;134 135 /* Update configuration for the clock setting */136 val = LP5521_DEFAULT_CFG;137 if (!lp55xx_is_extclk_used(chip))138 val |= LP5521_CLK_INT;139 140 val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;141 142 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);143 if (ret)144 return ret;145 146 /* Initialize all channels PWM to zero -> leds off */147 lp55xx_write(chip, LP5521_REG_R_PWM, 0);148 lp55xx_write(chip, LP5521_REG_G_PWM, 0);149 lp55xx_write(chip, LP5521_REG_B_PWM, 0);150 151 /* Set engines are set to run state when OP_MODE enables engines */152 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);153 if (ret)154 return ret;155 156 lp5521_wait_enable_done();157 158 return 0;159}160 161static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)162{163 struct lp55xx_platform_data *pdata = chip->pdata;164 int ret;165 u8 status;166 167 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);168 if (ret < 0)169 return ret;170 171 if (pdata->clock_mode != LP55XX_CLOCK_EXT)172 return 0;173 174 /* Check that ext clock is really in use if requested */175 if ((status & LP5521_EXT_CLK_USED) == 0)176 return -EIO;177 178 return 0;179}180 181static ssize_t lp5521_selftest(struct device *dev,182 struct device_attribute *attr,183 char *buf)184{185 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));186 struct lp55xx_chip *chip = led->chip;187 int ret;188 189 guard(mutex)(&chip->lock);190 191 ret = lp5521_run_selftest(chip, buf);192 193 return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");194}195 196/* device attributes */197LP55XX_DEV_ATTR_ENGINE_MODE(1);198LP55XX_DEV_ATTR_ENGINE_MODE(2);199LP55XX_DEV_ATTR_ENGINE_MODE(3);200LP55XX_DEV_ATTR_ENGINE_LOAD(1);201LP55XX_DEV_ATTR_ENGINE_LOAD(2);202LP55XX_DEV_ATTR_ENGINE_LOAD(3);203static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);204 205static struct attribute *lp5521_attributes[] = {206 &dev_attr_engine1_mode.attr,207 &dev_attr_engine2_mode.attr,208 &dev_attr_engine3_mode.attr,209 &dev_attr_engine1_load.attr,210 &dev_attr_engine2_load.attr,211 &dev_attr_engine3_load.attr,212 &dev_attr_selftest.attr,213 NULL214};215 216static const struct attribute_group lp5521_group = {217 .attrs = lp5521_attributes,218};219 220/* Chip specific configurations */221static struct lp55xx_device_config lp5521_cfg = {222 .reg_op_mode = {223 .addr = LP5521_REG_OP_MODE,224 },225 .reg_exec = {226 .addr = LP5521_REG_ENABLE,227 },228 .reset = {229 .addr = LP5521_REG_RESET,230 .val = LP5521_RESET,231 },232 .enable = {233 .addr = LP5521_REG_ENABLE,234 .val = LP5521_ENABLE_DEFAULT,235 },236 .prog_mem_base = {237 .addr = LP5521_REG_R_PROG_MEM,238 },239 .reg_led_pwm_base = {240 .addr = LP5521_REG_LED_PWM_BASE,241 },242 .reg_led_current_base = {243 .addr = LP5521_REG_LED_CURRENT_BASE,244 },245 .max_channel = LP5521_MAX_LEDS,246 .post_init_device = lp5521_post_init_device,247 .brightness_fn = lp55xx_led_brightness,248 .multicolor_brightness_fn = lp55xx_multicolor_brightness,249 .set_led_current = lp55xx_set_led_current,250 .firmware_cb = lp55xx_firmware_loaded_cb,251 .run_engine = lp5521_run_engine,252 .dev_attr_group = &lp5521_group,253};254 255static const struct i2c_device_id lp5521_id[] = {256 { "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */257 { }258};259MODULE_DEVICE_TABLE(i2c, lp5521_id);260 261static const struct of_device_id of_lp5521_leds_match[] = {262 { .compatible = "national,lp5521", .data = &lp5521_cfg, },263 {},264};265 266MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);267 268static struct i2c_driver lp5521_driver = {269 .driver = {270 .name = "lp5521",271 .of_match_table = of_lp5521_leds_match,272 },273 .probe = lp55xx_probe,274 .remove = lp55xx_remove,275 .id_table = lp5521_id,276};277 278module_i2c_driver(lp5521_driver);279 280MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");281MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");282MODULE_DESCRIPTION("LP5521 LED engine");283MODULE_LICENSE("GPL v2");284