drivers/leds/leds-lp3952.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  *  LED driver for TI lp3952 controller
0004  *
0005  *  Copyright (C) 2016, DAQRI, LLC.
0006  *  Author: Tony Makkiel <tony.makkiel@daqri.com>
0007  */
0008
0009 #include <linux/delay.h>
0010 #include <linux/gpio/consumer.h>
0011 #include <linux/i2c.h>
0012 #include <linux/io.h>
0013 #include <linux/kernel.h>
0014 #include <linux/leds.h>
0015 #include <linux/leds-lp3952.h>
0016 #include <linux/module.h>
0017 #include <linux/notifier.h>
0018 #include <linux/platform_device.h>
0019 #include <linux/pm.h>
0020 #include <linux/reboot.h>
0021 #include <linux/regmap.h>
0022
0023 static int lp3952_register_write(struct i2c_client *client, u8 reg, u8 val)
0024 {
0025     int ret;
0026     struct lp3952_led_array *priv = i2c_get_clientdata(client);
0027
0028     ret = regmap_write(priv->regmap, reg, val);
0029
0030     if (ret)
0031         dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
0032             __func__, reg, val, ret);
0033     return ret;
0034 }
0035
0036 static void lp3952_on_off(struct lp3952_led_array *priv,
0037               enum lp3952_leds led_id, bool on)
0038 {
0039     int ret, val;
0040
0041     dev_dbg(&priv->client->dev, "%s LED %d to %d\n", __func__, led_id, on);
0042
0043     val = 1 << led_id;
0044     if (led_id == LP3952_LED_ALL)
0045         val = LP3952_LED_MASK_ALL;
0046
0047     ret = regmap_update_bits(priv->regmap, LP3952_REG_LED_CTRL, val,
0048                  on ? val : 0);
0049     if (ret)
0050         dev_err(&priv->client->dev, "%s, Error %d\n", __func__, ret);
0051 }
0052
0053 /*
0054  * Using Imax to control brightness. There are 4 possible
0055  * setting 25, 50, 75 and 100 % of Imax. Possible values are
0056  * values 0-4. 0 meaning turn off.
0057  */
0058 static int lp3952_set_brightness(struct led_classdev *cdev,
0059                  enum led_brightness value)
0060 {
0061     unsigned int reg, shift_val;
0062     struct lp3952_ctrl_hdl *led = container_of(cdev,
0063                            struct lp3952_ctrl_hdl,
0064                            cdev);
0065     struct lp3952_led_array *priv = (struct lp3952_led_array *)led->priv;
0066
0067     dev_dbg(cdev->dev, "Brightness request: %d on %d\n", value,
0068         led->channel);
0069
0070     if (value == LED_OFF) {
0071         lp3952_on_off(priv, led->channel, false);
0072         return 0;
0073     }
0074
0075     if (led->channel > LP3952_RED_1) {
0076         dev_err(cdev->dev, " %s Invalid LED requested", __func__);
0077         return -EINVAL;
0078     }
0079
0080     if (led->channel >= LP3952_BLUE_1) {
0081         reg = LP3952_REG_RGB1_MAX_I_CTRL;
0082         shift_val = (led->channel - LP3952_BLUE_1) * 2;
0083     } else {
0084         reg = LP3952_REG_RGB2_MAX_I_CTRL;
0085         shift_val = led->channel * 2;
0086     }
0087
0088     /* Enable the LED in case it is not enabled already */
0089     lp3952_on_off(priv, led->channel, true);
0090
0091     return regmap_update_bits(priv->regmap, reg, 3 << shift_val,
0092                   --value << shift_val);
0093 }
0094
0095 static int lp3952_get_label(struct device *dev, const char *label, char *dest)
0096 {
0097     int ret;
0098     const char *str;
0099
0100     ret = device_property_read_string(dev, label, &str);
0101     if (ret)
0102         return ret;
0103
0104     strncpy(dest, str, LP3952_LABEL_MAX_LEN);
0105     return 0;
0106 }
0107
0108 static int lp3952_register_led_classdev(struct lp3952_led_array *priv)
0109 {
0110     int i, acpi_ret, ret = -ENODEV;
0111     static const char *led_name_hdl[LP3952_LED_ALL] = {
0112         "blue2",
0113         "green2",
0114         "red2",
0115         "blue1",
0116         "green1",
0117         "red1"
0118     };
0119
0120     for (i = 0; i < LP3952_LED_ALL; i++) {
0121         acpi_ret = lp3952_get_label(&priv->client->dev, led_name_hdl[i],
0122                         priv->leds[i].name);
0123         if (acpi_ret)
0124             continue;
0125
0126         priv->leds[i].cdev.name = priv->leds[i].name;
0127         priv->leds[i].cdev.brightness = LED_OFF;
0128         priv->leds[i].cdev.max_brightness = LP3952_BRIGHT_MAX;
0129         priv->leds[i].cdev.brightness_set_blocking =
0130                 lp3952_set_brightness;
0131         priv->leds[i].channel = i;
0132         priv->leds[i].priv = priv;
0133
0134         ret = devm_led_classdev_register(&priv->client->dev,
0135                          &priv->leds[i].cdev);
0136         if (ret < 0) {
0137             dev_err(&priv->client->dev,
0138                 "couldn't register LED %s\n",
0139                 priv->leds[i].cdev.name);
0140             break;
0141         }
0142     }
0143     return ret;
0144 }
0145
0146 static int lp3952_set_pattern_gen_cmd(struct lp3952_led_array *priv,
0147                       u8 cmd_index, u8 r, u8 g, u8 b,
0148                       enum lp3952_tt tt, enum lp3952_cet cet)
0149 {
0150     int ret;
0151     struct ptrn_gen_cmd line = {
0152         {
0153             {
0154                 .r = r,
0155                 .g = g,
0156                 .b = b,
0157                 .cet = cet,
0158                 .tt = tt
0159             }
0160         }
0161     };
0162
0163     if (cmd_index >= LP3952_CMD_REG_COUNT)
0164         return -EINVAL;
0165
0166     ret = lp3952_register_write(priv->client,
0167                     LP3952_REG_CMD_0 + cmd_index * 2,
0168                     line.bytes.msb);
0169     if (ret)
0170         return ret;
0171
0172     return lp3952_register_write(priv->client,
0173                       LP3952_REG_CMD_0 + cmd_index * 2 + 1,
0174                       line.bytes.lsb);
0175 }
0176
0177 static int lp3952_configure(struct lp3952_led_array *priv)
0178 {
0179     int ret;
0180
0181     /* Disable any LEDs on from any previous conf. */
0182     ret = lp3952_register_write(priv->client, LP3952_REG_LED_CTRL, 0);
0183     if (ret)
0184         return ret;
0185
0186     /* enable rgb patter, loop */
0187     ret = lp3952_register_write(priv->client, LP3952_REG_PAT_GEN_CTRL,
0188                     LP3952_PATRN_LOOP | LP3952_PATRN_GEN_EN);
0189     if (ret)
0190         return ret;
0191
0192     /* Update Bit 6 (Active mode), Select both Led sets, Bit [1:0] */
0193     ret = lp3952_register_write(priv->client, LP3952_REG_ENABLES,
0194                     LP3952_ACTIVE_MODE | LP3952_INT_B00ST_LDR);
0195     if (ret)
0196         return ret;
0197
0198     /* Set Cmd1 for RGB intensity,cmd and transition time */
0199     return lp3952_set_pattern_gen_cmd(priv, 0, I46, I71, I100, TT0,
0200                        CET197);
0201 }
0202
0203 static const struct regmap_config lp3952_regmap = {
0204     .reg_bits = 8,
0205     .val_bits = 8,
0206     .max_register = REG_MAX,
0207     .cache_type = REGCACHE_RBTREE,
0208 };
0209
0210 static int lp3952_probe(struct i2c_client *client,
0211             const struct i2c_device_id *id)
0212 {
0213     int status;
0214     struct lp3952_led_array *priv;
0215
0216     priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
0217     if (!priv)
0218         return -ENOMEM;
0219
0220     priv->client = client;
0221
0222     priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",
0223                        GPIOD_OUT_HIGH);
0224     if (IS_ERR(priv->enable_gpio)) {
0225         status = PTR_ERR(priv->enable_gpio);
0226         dev_err(&client->dev, "Failed to enable gpio: %d\n", status);
0227         return status;
0228     }
0229
0230     priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);
0231     if (IS_ERR(priv->regmap)) {
0232         int err = PTR_ERR(priv->regmap);
0233
0234         dev_err(&client->dev, "Failed to allocate register map: %d\n",
0235             err);
0236         return err;
0237     }
0238
0239     i2c_set_clientdata(client, priv);
0240
0241     status = lp3952_configure(priv);
0242     if (status) {
0243         dev_err(&client->dev, "Probe failed. Device not found (%d)\n",
0244             status);
0245         return status;
0246     }
0247
0248     status = lp3952_register_led_classdev(priv);
0249     if (status) {
0250         dev_err(&client->dev, "Unable to register led_classdev: %d\n",
0251             status);
0252         return status;
0253     }
0254
0255     return 0;
0256 }
0257
0258 static int lp3952_remove(struct i2c_client *client)
0259 {
0260     struct lp3952_led_array *priv;
0261
0262     priv = i2c_get_clientdata(client);
0263     lp3952_on_off(priv, LP3952_LED_ALL, false);
0264     gpiod_set_value(priv->enable_gpio, 0);
0265
0266     return 0;
0267 }
0268
0269 static const struct i2c_device_id lp3952_id[] = {
0270     {LP3952_NAME, 0},
0271     {}
0272 };
0273 MODULE_DEVICE_TABLE(i2c, lp3952_id);
0274
0275 static struct i2c_driver lp3952_i2c_driver = {
0276     .driver = {
0277             .name = LP3952_NAME,
0278     },
0279     .probe = lp3952_probe,
0280     .remove = lp3952_remove,
0281     .id_table = lp3952_id,
0282 };
0283
0284 module_i2c_driver(lp3952_i2c_driver);
0285
0286 MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
0287 MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
0288 MODULE_LICENSE("GPL v2");