1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * TI LP8501 9 channel LED Driver 4 * 5 * Copyright (C) 2013 Texas Instruments 6 * 7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com> 8 */ 9 10 #include <linux/delay.h> 11 #include <linux/firmware.h> 12 #include <linux/i2c.h> 13 #include <linux/init.h> 14 #include <linux/leds.h> 15 #include <linux/module.h> 16 #include <linux/mutex.h> 17 #include <linux/of.h> 18 #include <linux/platform_data/leds-lp55xx.h> 19 #include <linux/slab.h> 20 21 #include "leds-lp55xx-common.h" 22 23 #define LP8501_PROGRAM_LENGTH 32 24 #define LP8501_PAGES_PER_ENGINE 1 25 #define LP8501_MAX_LEDS 9 26 27 /* Registers */ 28 #define LP8501_REG_ENABLE 0x00 29 #define LP8501_ENABLE BIT(6) 30 #define LP8501_EXEC_M 0x3F 31 #define LP8501_EXEC_ENG1_M 0x30 32 #define LP8501_EXEC_ENG2_M 0x0C 33 #define LP8501_EXEC_ENG3_M 0x03 34 #define LP8501_RUN_ENG1 0x20 35 #define LP8501_RUN_ENG2 0x08 36 #define LP8501_RUN_ENG3 0x02 37 38 #define LP8501_REG_OP_MODE 0x01 39 #define LP8501_MODE_ENG1_M 0x30 40 #define LP8501_MODE_ENG2_M 0x0C 41 #define LP8501_MODE_ENG3_M 0x03 42 #define LP8501_LOAD_ENG1 0x10 43 #define LP8501_LOAD_ENG2 0x04 44 #define LP8501_LOAD_ENG3 0x01 45 46 #define LP8501_REG_PWR_CONFIG 0x05 47 #define LP8501_PWR_CONFIG_M 0x03 48 49 #define LP8501_REG_LED_PWM_BASE 0x16 50 51 #define LP8501_REG_LED_CURRENT_BASE 0x26 52 53 #define LP8501_REG_CONFIG 0x36 54 #define LP8501_PWM_PSAVE BIT(7) 55 #define LP8501_AUTO_INC BIT(6) 56 #define LP8501_PWR_SAVE BIT(5) 57 #define LP8501_CP_MODE_MASK 0x18 58 #define LP8501_CP_MODE_SHIFT 3 59 #define LP8501_INT_CLK BIT(0) 60 #define LP8501_DEFAULT_CFG (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE) 61 62 #define LP8501_REG_STATUS 0x3A 63 #define LP8501_ENGINE_BUSY BIT(4) 64 65 #define LP8501_REG_RESET 0x3D 66 #define LP8501_RESET 0xFF 67 68 #define LP8501_REG_PROG_PAGE_SEL 0x4F 69 #define LP8501_PAGE_ENG1 0 70 #define LP8501_PAGE_ENG2 1 71 #define LP8501_PAGE_ENG3 2 72 73 #define LP8501_REG_PROG_MEM 0x50 74 75 #define LP8501_ENG1_IS_LOADING(mode) \ 76 ((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1) 77 #define LP8501_ENG2_IS_LOADING(mode) \ 78 ((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2) 79 #define LP8501_ENG3_IS_LOADING(mode) \ 80 ((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3) 81 82 static inline void lp8501_wait_opmode_done(void) 83 { 84 usleep_range(1000, 2000); 85 } 86 87 static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current) 88 { 89 led->led_current = led_current; 90 lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr, 91 led_current); 92 } 93 94 static int lp8501_post_init_device(struct lp55xx_chip *chip) 95 { 96 int ret; 97 u8 val = LP8501_DEFAULT_CFG; 98 99 ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE); 100 if (ret) 101 return ret; 102 103 /* Chip startup time is 500 us, 1 - 2 ms gives some margin */ 104 usleep_range(1000, 2000); 105 106 if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT) 107 val |= LP8501_INT_CLK; 108 109 val |= (chip->pdata->charge_pump_mode << LP8501_CP_MODE_SHIFT) & LP8501_CP_MODE_MASK; 110 111 ret = lp55xx_write(chip, LP8501_REG_CONFIG, val); 112 if (ret) 113 return ret; 114 115 /* Power selection for each output */ 116 return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG, 117 LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel); 118 } 119 120 static void lp8501_turn_off_channels(struct lp55xx_chip *chip) 121 { 122 int i; 123 124 for (i = 0; i < LP8501_MAX_LEDS; i++) 125 lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0); 126 } 127 128 static void lp8501_run_engine(struct lp55xx_chip *chip, bool start) 129 { 130 /* stop engine */ 131 if (!start) { 132 lp55xx_stop_all_engine(chip); 133 lp8501_turn_off_channels(chip); 134 return; 135 } 136 137 lp55xx_run_engine_common(chip); 138 } 139 140 static void lp8501_firmware_loaded(struct lp55xx_chip *chip) 141 { 142 const struct firmware *fw = chip->fw; 143 144 if (fw->size > LP8501_PROGRAM_LENGTH) { 145 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 146 fw->size); 147 return; 148 } 149 150 /* 151 * Program memory sequence 152 * 1) set engine mode to "LOAD" 153 * 2) write firmware data into program memory 154 */ 155 156 lp55xx_load_engine(chip); 157 lp55xx_update_program_memory(chip, fw->data, fw->size); 158 } 159 160 static int lp8501_led_brightness(struct lp55xx_led *led) 161 { 162 struct lp55xx_chip *chip = led->chip; 163 int ret; 164 165 mutex_lock(&chip->lock); 166 ret = lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + led->chan_nr, 167 led->brightness); 168 mutex_unlock(&chip->lock); 169 170 return ret; 171 } 172 173 /* Chip specific configurations */ 174 static struct lp55xx_device_config lp8501_cfg = { 175 .reg_op_mode = { 176 .addr = LP8501_REG_OP_MODE, 177 }, 178 .reg_exec = { 179 .addr = LP8501_REG_ENABLE, 180 }, 181 .engine_busy = { 182 .addr = LP8501_REG_STATUS, 183 .mask = LP8501_ENGINE_BUSY, 184 }, 185 .reset = { 186 .addr = LP8501_REG_RESET, 187 .val = LP8501_RESET, 188 }, 189 .enable = { 190 .addr = LP8501_REG_ENABLE, 191 .val = LP8501_ENABLE, 192 }, 193 .prog_mem_base = { 194 .addr = LP8501_REG_PROG_MEM, 195 }, 196 .pages_per_engine = LP8501_PAGES_PER_ENGINE, 197 .max_channel = LP8501_MAX_LEDS, 198 .post_init_device = lp8501_post_init_device, 199 .brightness_fn = lp8501_led_brightness, 200 .set_led_current = lp8501_set_led_current, 201 .firmware_cb = lp8501_firmware_loaded, 202 .run_engine = lp8501_run_engine, 203 }; 204 205 static const struct i2c_device_id lp8501_id[] = { 206 { "lp8501", .driver_data = (kernel_ulong_t)&lp8501_cfg, }, 207 { } 208 }; 209 MODULE_DEVICE_TABLE(i2c, lp8501_id); 210 211 static const struct of_device_id of_lp8501_leds_match[] = { 212 { .compatible = "ti,lp8501", .data = &lp8501_cfg, }, 213 {}, 214 }; 215 216 MODULE_DEVICE_TABLE(of, of_lp8501_leds_match); 217 218 static struct i2c_driver lp8501_driver = { 219 .driver = { 220 .name = "lp8501", 221 .of_match_table = of_lp8501_leds_match, 222 }, 223 .probe = lp55xx_probe, 224 .remove = lp55xx_remove, 225 .id_table = lp8501_id, 226 }; 227 228 module_i2c_driver(lp8501_driver); 229 230 MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver"); 231 MODULE_AUTHOR("Milo Kim"); 232 MODULE_LICENSE("GPL"); 233