linux/drivers/leds/leds-lp3952.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *      LED driver for TI lp3952 controller
   4 *
   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 possible
  55 * setting 25, 50, 75 and 100 % of Imax. Possible values are
  56 * 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        strncpy(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 = tt
 159                        }
 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_RBTREE,
 208};
 209
 210static int lp3952_probe(struct i2c_client *client,
 211                        const struct i2c_device_id *id)
 212{
 213        int status;
 214        struct lp3952_led_array *priv;
 215
 216        priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
 217        if (!priv)
 218                return -ENOMEM;
 219
 220        priv->client = client;
 221
 222        priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",
 223                                           GPIOD_OUT_HIGH);
 224        if (IS_ERR(priv->enable_gpio)) {
 225                status = PTR_ERR(priv->enable_gpio);
 226                dev_err(&client->dev, "Failed to enable gpio: %d\n", status);
 227                return status;
 228        }
 229
 230        priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);
 231        if (IS_ERR(priv->regmap)) {
 232                int err = PTR_ERR(priv->regmap);
 233
 234                dev_err(&client->dev, "Failed to allocate register map: %d\n",
 235                        err);
 236                return err;
 237        }
 238
 239        i2c_set_clientdata(client, priv);
 240
 241        status = lp3952_configure(priv);
 242        if (status) {
 243                dev_err(&client->dev, "Probe failed. Device not found (%d)\n",
 244                        status);
 245                return status;
 246        }
 247
 248        status = lp3952_register_led_classdev(priv);
 249        if (status) {
 250                dev_err(&client->dev, "Unable to register led_classdev: %d\n",
 251                        status);
 252                return status;
 253        }
 254
 255        return 0;
 256}
 257
 258static int lp3952_remove(struct i2c_client *client)
 259{
 260        struct lp3952_led_array *priv;
 261
 262        priv = i2c_get_clientdata(client);
 263        lp3952_on_off(priv, LP3952_LED_ALL, false);
 264        gpiod_set_value(priv->enable_gpio, 0);
 265
 266        return 0;
 267}
 268
 269static const struct i2c_device_id lp3952_id[] = {
 270        {LP3952_NAME, 0},
 271        {}
 272};
 273MODULE_DEVICE_TABLE(i2c, lp3952_id);
 274
 275static struct i2c_driver lp3952_i2c_driver = {
 276        .driver = {
 277                        .name = LP3952_NAME,
 278        },
 279        .probe = lp3952_probe,
 280        .remove = lp3952_remove,
 281        .id_table = lp3952_id,
 282};
 283
 284module_i2c_driver(lp3952_i2c_driver);
 285
 286MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
 287MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
 288MODULE_LICENSE("GPL v2");
 289