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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * LED driver for TI lp3952 controller4 *5 * Copyright (C) 2016, DAQRI, LLC.6 * Author: Tony Makkiel <tony.makkiel@daqri.com>7 */8 9#include <linux/delay.h>10#include <linux/gpio/consumer.h>11#include <linux/i2c.h>12#include <linux/io.h>13#include <linux/kernel.h>14#include <linux/leds.h>15#include <linux/leds-lp3952.h>16#include <linux/module.h>17#include <linux/notifier.h>18#include <linux/platform_device.h>19#include <linux/pm.h>20#include <linux/reboot.h>21#include <linux/regmap.h>22 23static int lp3952_register_write(struct i2c_client *client, u8 reg, u8 val)24{25 int ret;26 struct lp3952_led_array *priv = i2c_get_clientdata(client);27 28 ret = regmap_write(priv->regmap, reg, val);29 30 if (ret)31 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",32 __func__, reg, val, ret);33 return ret;34}35 36static void lp3952_on_off(struct lp3952_led_array *priv,37 enum lp3952_leds led_id, bool on)38{39 int ret, val;40 41 dev_dbg(&priv->client->dev, "%s LED %d to %d\n", __func__, led_id, on);42 43 val = 1 << led_id;44 if (led_id == LP3952_LED_ALL)45 val = LP3952_LED_MASK_ALL;46 47 ret = regmap_update_bits(priv->regmap, LP3952_REG_LED_CTRL, val,48 on ? val : 0);49 if (ret)50 dev_err(&priv->client->dev, "%s, Error %d\n", __func__, ret);51}52 53/*54 * Using Imax to control brightness. There are 4 possible55 * setting 25, 50, 75 and 100 % of Imax. Possible values are56 * values 0-4. 0 meaning turn off.57 */58static int lp3952_set_brightness(struct led_classdev *cdev,59 enum led_brightness value)60{61 unsigned int reg, shift_val;62 struct lp3952_ctrl_hdl *led = container_of(cdev,63 struct lp3952_ctrl_hdl,64 cdev);65 struct lp3952_led_array *priv = (struct lp3952_led_array *)led->priv;66 67 dev_dbg(cdev->dev, "Brightness request: %d on %d\n", value,68 led->channel);69 70 if (value == LED_OFF) {71 lp3952_on_off(priv, led->channel, false);72 return 0;73 }74 75 if (led->channel > LP3952_RED_1) {76 dev_err(cdev->dev, " %s Invalid LED requested", __func__);77 return -EINVAL;78 }79 80 if (led->channel >= LP3952_BLUE_1) {81 reg = LP3952_REG_RGB1_MAX_I_CTRL;82 shift_val = (led->channel - LP3952_BLUE_1) * 2;83 } else {84 reg = LP3952_REG_RGB2_MAX_I_CTRL;85 shift_val = led->channel * 2;86 }87 88 /* Enable the LED in case it is not enabled already */89 lp3952_on_off(priv, led->channel, true);90 91 return regmap_update_bits(priv->regmap, reg, 3 << shift_val,92 --value << shift_val);93}94 95static int lp3952_get_label(struct device *dev, const char *label, char *dest)96{97 int ret;98 const char *str;99 100 ret = device_property_read_string(dev, label, &str);101 if (ret)102 return ret;103 104 strscpy(dest, str, LP3952_LABEL_MAX_LEN);105 return 0;106}107 108static int lp3952_register_led_classdev(struct lp3952_led_array *priv)109{110 int i, acpi_ret, ret = -ENODEV;111 static const char *led_name_hdl[LP3952_LED_ALL] = {112 "blue2",113 "green2",114 "red2",115 "blue1",116 "green1",117 "red1"118 };119 120 for (i = 0; i < LP3952_LED_ALL; i++) {121 acpi_ret = lp3952_get_label(&priv->client->dev, led_name_hdl[i],122 priv->leds[i].name);123 if (acpi_ret)124 continue;125 126 priv->leds[i].cdev.name = priv->leds[i].name;127 priv->leds[i].cdev.brightness = LED_OFF;128 priv->leds[i].cdev.max_brightness = LP3952_BRIGHT_MAX;129 priv->leds[i].cdev.brightness_set_blocking =130 lp3952_set_brightness;131 priv->leds[i].channel = i;132 priv->leds[i].priv = priv;133 134 ret = devm_led_classdev_register(&priv->client->dev,135 &priv->leds[i].cdev);136 if (ret < 0) {137 dev_err(&priv->client->dev,138 "couldn't register LED %s\n",139 priv->leds[i].cdev.name);140 break;141 }142 }143 return ret;144}145 146static int lp3952_set_pattern_gen_cmd(struct lp3952_led_array *priv,147 u8 cmd_index, u8 r, u8 g, u8 b,148 enum lp3952_tt tt, enum lp3952_cet cet)149{150 int ret;151 struct ptrn_gen_cmd line = {152 {153 {154 .r = r,155 .g = g,156 .b = b,157 .cet = cet,158 .tt = tt159 }160 }161 };162 163 if (cmd_index >= LP3952_CMD_REG_COUNT)164 return -EINVAL;165 166 ret = lp3952_register_write(priv->client,167 LP3952_REG_CMD_0 + cmd_index * 2,168 line.bytes.msb);169 if (ret)170 return ret;171 172 return lp3952_register_write(priv->client,173 LP3952_REG_CMD_0 + cmd_index * 2 + 1,174 line.bytes.lsb);175}176 177static int lp3952_configure(struct lp3952_led_array *priv)178{179 int ret;180 181 /* Disable any LEDs on from any previous conf. */182 ret = lp3952_register_write(priv->client, LP3952_REG_LED_CTRL, 0);183 if (ret)184 return ret;185 186 /* enable rgb patter, loop */187 ret = lp3952_register_write(priv->client, LP3952_REG_PAT_GEN_CTRL,188 LP3952_PATRN_LOOP | LP3952_PATRN_GEN_EN);189 if (ret)190 return ret;191 192 /* Update Bit 6 (Active mode), Select both Led sets, Bit [1:0] */193 ret = lp3952_register_write(priv->client, LP3952_REG_ENABLES,194 LP3952_ACTIVE_MODE | LP3952_INT_B00ST_LDR);195 if (ret)196 return ret;197 198 /* Set Cmd1 for RGB intensity,cmd and transition time */199 return lp3952_set_pattern_gen_cmd(priv, 0, I46, I71, I100, TT0,200 CET197);201}202 203static const struct regmap_config lp3952_regmap = {204 .reg_bits = 8,205 .val_bits = 8,206 .max_register = REG_MAX,207 .cache_type = REGCACHE_MAPLE,208};209 210static void gpio_set_low_action(void *data)211{212 struct lp3952_led_array *priv = data;213 214 gpiod_set_value(priv->enable_gpio, 0);215}216 217static int lp3952_probe(struct i2c_client *client)218{219 int status;220 struct lp3952_led_array *priv;221 222 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);223 if (!priv)224 return -ENOMEM;225 226 priv->client = client;227 228 priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",229 GPIOD_OUT_HIGH);230 if (IS_ERR(priv->enable_gpio)) {231 status = PTR_ERR(priv->enable_gpio);232 dev_err(&client->dev, "Failed to enable gpio: %d\n", status);233 return status;234 }235 236 status = devm_add_action(&client->dev, gpio_set_low_action, priv);237 if (status)238 return status;239 240 priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);241 if (IS_ERR(priv->regmap)) {242 int err = PTR_ERR(priv->regmap);243 244 dev_err(&client->dev, "Failed to allocate register map: %d\n",245 err);246 return err;247 }248 249 i2c_set_clientdata(client, priv);250 251 status = lp3952_configure(priv);252 if (status) {253 dev_err(&client->dev, "Probe failed. Device not found (%d)\n",254 status);255 return status;256 }257 258 status = lp3952_register_led_classdev(priv);259 if (status) {260 dev_err(&client->dev, "Unable to register led_classdev: %d\n",261 status);262 return status;263 }264 265 return 0;266}267 268static const struct i2c_device_id lp3952_id[] = {269 { LP3952_NAME },270 {}271};272MODULE_DEVICE_TABLE(i2c, lp3952_id);273 274static struct i2c_driver lp3952_i2c_driver = {275 .driver = {276 .name = LP3952_NAME,277 },278 .probe = lp3952_probe,279 .id_table = lp3952_id,280};281 282module_i2c_driver(lp3952_i2c_driver);283 284MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");285MODULE_DESCRIPTION("lp3952 I2C LED controller driver");286MODULE_LICENSE("GPL v2");287