1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * LP5521 LED chip driver. 4 * 5 * Copyright (C) 2010 Nokia Corporation 6 * Copyright (C) 2012 Texas Instruments 7 * 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 3 26 #define LP5521_CMD_DIRECT 0x3F 27 28 /* Registers */ 29 #define LP5521_REG_ENABLE 0x00 30 #define LP5521_REG_OP_MODE 0x01 31 #define LP5521_REG_R_PWM 0x02 32 #define LP5521_REG_G_PWM 0x03 33 #define LP5521_REG_B_PWM 0x04 34 #define LP5521_REG_R_CURRENT 0x05 35 #define LP5521_REG_G_CURRENT 0x06 36 #define LP5521_REG_B_CURRENT 0x07 37 #define LP5521_REG_CONFIG 0x08 38 #define LP5521_REG_STATUS 0x0C 39 #define LP5521_REG_RESET 0x0D 40 #define LP5521_REG_R_PROG_MEM 0x10 41 #define LP5521_REG_G_PROG_MEM 0x30 42 #define LP5521_REG_B_PROG_MEM 0x50 43 44 /* Base register to set LED current */ 45 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT 46 /* Base register to set the brightness */ 47 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM 48 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 0x2A 53 #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 3 63 #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 0x08 69 70 /* default R channel current register value */ 71 #define LP5521_REG_R_CURR_DEFAULT 0xAF 72 73 /* Reset register value */ 74 #define LP5521_RESET 0xFF 75 76 static 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 82 static 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 88 static 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 } 104 105 static 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 channel 112 * current reg. This is dummy read is required on some platforms - 113 * otherwise further access to the R G B channels in the 114 * 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 } 160 161 static 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 } 180 181 static 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 */ 197 LP55XX_DEV_ATTR_ENGINE_MODE(1); 198 LP55XX_DEV_ATTR_ENGINE_MODE(2); 199 LP55XX_DEV_ATTR_ENGINE_MODE(3); 200 LP55XX_DEV_ATTR_ENGINE_LOAD(1); 201 LP55XX_DEV_ATTR_ENGINE_LOAD(2); 202 LP55XX_DEV_ATTR_ENGINE_LOAD(3); 203 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest); 204 205 static 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 NULL 214 }; 215 216 static const struct attribute_group lp5521_group = { 217 .attrs = lp5521_attributes, 218 }; 219 220 /* Chip specific configurations */ 221 static 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 }; 254 255 static const struct i2c_device_id lp5521_id[] = { 256 { "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */ 257 { } 258 }; 259 MODULE_DEVICE_TABLE(i2c, lp5521_id); 260 261 static const struct of_device_id of_lp5521_leds_match[] = { 262 { .compatible = "national,lp5521", .data = &lp5521_cfg, }, 263 {}, 264 }; 265 266 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match); 267 268 static 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 }; 277 278 module_i2c_driver(lp5521_driver); 279 280 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo"); 281 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); 282 MODULE_DESCRIPTION("LP5521 LED engine"); 283 MODULE_LICENSE("GPL v2"); 284