target/linux/mediatek/files/drivers/leds/leds-ubnt-ledbar.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <linux/delay.h>
   4 #include <linux/i2c.h>
   5 #include <linux/init.h>
   6 #include <linux/leds.h>
   7 #include <linux/module.h>
   8 #include <linux/mutex.h>
   9 #include <linux/of.h>
  10 #include <linux/of_gpio.h>
  11 #include <linux/gpio/consumer.h>
  12
  13 /**
  14  * Driver for the Ubiquiti RGB LED controller (LEDBAR).
  15  * This Controller is based on a Holtek HT32F52241 and connected
  16  * via I2C.
  17  *
  18  *  - The Controller needs an enable signal set to high when
  19  *    performing a transaction. On the U6-LR, this is located
  20  *    at Pin 18 (R6902)
  21  *
  22  *  - The Pin is also printed when calling the "usetled" function
  23  *    contained in the ubntapp bootloader application.
  24  */
  25
  26 #define UBNT_LEDBAR_MAX_BRIGHTNESS      0xff
  27
  28 #define UBNT_LEDBAR_TRANSACTION_LENGTH  8
  29 #define UBNT_LEDBAR_TRANSACTION_SUCCESS (char) 0xaa
  30
  31 #define UBNT_LEDBAR_TRANSACTION_BLUE_IDX        2
  32 #define UBNT_LEDBAR_TRANSACTION_GREEN_IDX       3
  33 #define UBNT_LEDBAR_TRANSACTION_RED_IDX         4
  34
  35 struct ubnt_ledbar {
  36         struct mutex lock;
  37         struct i2c_client *client;
  38         struct led_classdev led_red;
  39         struct led_classdev led_green;
  40         struct led_classdev led_blue;
  41         struct gpio_desc *enable_gpio;
  42         struct gpio_desc *reset_gpio;
  43 };
  44
  45 static void ubnt_ledbar_perform_transaction(struct ubnt_ledbar *ledbar,
  46                                            const char *transaction, int len,
  47                                            char *result, int result_len)
  48 {
  49         int i;
  50
  51         for (i = 0; i < len; i++)
  52                 i2c_smbus_write_byte(ledbar->client, transaction[i]);
  53
  54         for (i = 0; i < result_len; i++)
  55                 result[i] = i2c_smbus_read_byte(ledbar->client);
  56 }
  57
  58 static int ubnt_ledbar_apply_state(struct ubnt_ledbar *ledbar)
  59 {
  60         char setup_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x10, 0x00, 0x00,
  61                                                           0x00, 0x00, 0x00, 0x11};
  62         char led_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x00, 0x00, 0x00,
  63                                                         0x00, 0x00, 0x01, 0x00};
  64         char i2c_response;
  65         int ret = 0;
  66
  67         mutex_lock(&ledbar->lock);
  68
  69         led_msg[UBNT_LEDBAR_TRANSACTION_BLUE_IDX] = ledbar->led_blue.brightness;
  70         led_msg[UBNT_LEDBAR_TRANSACTION_GREEN_IDX] = ledbar->led_green.brightness;
  71         led_msg[UBNT_LEDBAR_TRANSACTION_RED_IDX] = ledbar->led_red.brightness;
  72
  73         gpiod_set_value(ledbar->enable_gpio, 1);
  74
  75         msleep(10);
  76
  77         ubnt_ledbar_perform_transaction(ledbar, setup_msg, sizeof(setup_msg), &i2c_response, sizeof(i2c_response));
  78         if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
  79                 dev_err(&ledbar->client->dev, "Error initializing LED transaction: %02hhx\n", i2c_response);
  80                 ret = -EINVAL;
  81                 goto out_gpio;
  82         }
  83
  84         ubnt_ledbar_perform_transaction(ledbar, led_msg, sizeof(led_msg), &i2c_response, sizeof(i2c_response));
  85         if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
  86                 dev_err(&ledbar->client->dev, "Failed LED transaction: %02hhx\n", i2c_response);
  87                 ret = -EINVAL;
  88                 goto out_gpio;
  89         }
  90
  91         msleep(10);
  92 out_gpio:
  93         gpiod_set_value(ledbar->enable_gpio, 0);
  94
  95         mutex_unlock(&ledbar->lock);
  96
  97         return ret;
  98 }
  99
 100 static void ubnt_ledbar_reset(struct ubnt_ledbar *ledbar)
 101 {
 102         static const char init_msg[16] = {0x02, 0x81, 0xfd, 0x7e,
 103                                           0x00, 0x00, 0x00, 0x00,
 104                                           0x00, 0x00, 0x00, 0x00,
 105                                           0x00, 0x00, 0x00, 0x00};
 106         char init_response[4];
 107
 108         if (!ledbar->reset_gpio)
 109                 return;
 110
 111         mutex_lock(&ledbar->lock);
 112
 113         gpiod_set_value(ledbar->reset_gpio, 1);
 114         msleep(10);
 115         gpiod_set_value(ledbar->reset_gpio, 0);
 116
 117         msleep(10);
 118
 119         gpiod_set_value(ledbar->enable_gpio, 1);
 120         msleep(10);
 121         ubnt_ledbar_perform_transaction(ledbar, init_msg, sizeof(init_msg), init_response, sizeof(init_response));
 122         msleep(10);
 123         gpiod_set_value(ledbar->enable_gpio, 0);
 124
 125         mutex_unlock(&ledbar->lock);
 126 }
 127
 128 #define UBNT_LEDBAR_CONTROL_RGBS(name)                          \
 129 static int ubnt_ledbar_set_##name##_brightness(struct led_classdev *led_cdev,\
 130                                         enum led_brightness value)      \
 131 {                                                                       \
 132         struct ubnt_ledbar *ledbar = \
 133                         container_of(led_cdev, struct ubnt_ledbar, led_##name); \
 134         int ret; \
 135         led_cdev->brightness = value; \
 136         ret = ubnt_ledbar_apply_state(ledbar); \
 137         return ret; \
 138 }
 139
 140 UBNT_LEDBAR_CONTROL_RGBS(red);
 141 UBNT_LEDBAR_CONTROL_RGBS(green);
 142 UBNT_LEDBAR_CONTROL_RGBS(blue);
 143
 144
 145 static int ubnt_ledbar_init_led(struct device_node *np, struct ubnt_ledbar *ledbar,
 146                                 struct led_classdev *led_cdev)
 147 {
 148         struct led_init_data init_data = {};
 149         int ret;
 150
 151         if (!np)
 152                 return 0;
 153
 154         init_data.fwnode = of_fwnode_handle(np);
 155
 156         led_cdev->max_brightness = UBNT_LEDBAR_MAX_BRIGHTNESS;
 157
 158         ret = devm_led_classdev_register_ext(&ledbar->client->dev, led_cdev,
 159                                              &init_data);
 160         if (ret)
 161                 dev_err(&ledbar->client->dev, "led register err: %d\n", ret);
 162
 163         return ret;
 164 }
 165
 166
 167 static int ubnt_ledbar_probe(struct i2c_client *client,
 168                              const struct i2c_device_id *id)
 169 {
 170         struct device_node *np = client->dev.of_node;
 171         struct ubnt_ledbar *ledbar;
 172         int ret;
 173
 174         ledbar = devm_kzalloc(&client->dev, sizeof(*ledbar), GFP_KERNEL);
 175         if (!ledbar)
 176                 return -ENOMEM;
 177
 178         ledbar->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);
 179
 180         if (IS_ERR(ledbar->enable_gpio)) {
 181                 ret = PTR_ERR(ledbar->enable_gpio);
 182                 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 183                 return ret;
 184         }
 185
 186         ledbar->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW);
 187
 188         if (IS_ERR(ledbar->reset_gpio)) {
 189                 ret = PTR_ERR(ledbar->reset_gpio);
 190                 dev_err(&client->dev, "Failed to get reset gpio: %d\n", ret);
 191                 return ret;
 192         }
 193
 194         ledbar->client = client;
 195
 196         mutex_init(&ledbar->lock);
 197
 198         i2c_set_clientdata(client, ledbar);
 199
 200         // Reset and initialize the MCU
 201         ubnt_ledbar_reset(ledbar);
 202
 203         ledbar->led_red.brightness_set_blocking = ubnt_ledbar_set_red_brightness;
 204         ubnt_ledbar_init_led(of_get_child_by_name(np, "red"), ledbar, &ledbar->led_red);
 205
 206         ledbar->led_green.brightness_set_blocking = ubnt_ledbar_set_green_brightness;
 207         ubnt_ledbar_init_led(of_get_child_by_name(np, "green"), ledbar, &ledbar->led_green);
 208
 209         ledbar->led_blue.brightness_set_blocking = ubnt_ledbar_set_blue_brightness;
 210         ubnt_ledbar_init_led(of_get_child_by_name(np, "blue"), ledbar, &ledbar->led_blue);
 211
 212         return ubnt_ledbar_apply_state(ledbar);
 213 }
 214
 215 static int ubnt_ledbar_remove(struct i2c_client *client)
 216 {
 217         struct ubnt_ledbar *ledbar = i2c_get_clientdata(client);
 218
 219         mutex_destroy(&ledbar->lock);
 220
 221         return 0;
 222 }
 223
 224 static const struct i2c_device_id ubnt_ledbar_id[] = {
 225         { "ubnt-ledbar", 0 },
 226         { }
 227 };
 228 MODULE_DEVICE_TABLE(i2c, ubnt_ledbar_id);
 229
 230 static const struct of_device_id of_ubnt_ledbar_match[] = {
 231         { .compatible = "ubnt,ledbar", },
 232         {},
 233 };
 234 MODULE_DEVICE_TABLE(of, of_ubnt_ledbar_match);
 235
 236 static struct i2c_driver ubnt_ledbar_driver = {
 237         .driver = {
 238                 .name   = "ubnt-ledbar",
 239                 .of_match_table = of_ubnt_ledbar_match,
 240         },
 241         .probe          = ubnt_ledbar_probe,
 242         .remove         = ubnt_ledbar_remove,
 243         .id_table       = ubnt_ledbar_id,
 244 };
 245 module_i2c_driver(ubnt_ledbar_driver);
 246
 247 MODULE_DESCRIPTION("Ubiquiti LEDBAR driver");
 248 MODULE_AUTHOR("David Bauer <mail@david-bauer.net>");
 249 MODULE_LICENSE("GPL v2");