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
lp3952_register_write(struct i2c_client * client,u8 reg,u8 val)23 static 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
lp3952_on_off(struct lp3952_led_array * priv,enum lp3952_leds led_id,bool on)36 static 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 */
lp3952_set_brightness(struct led_classdev * cdev,enum led_brightness value)58 static 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
lp3952_get_label(struct device * dev,const char * label,char * dest)95 static 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
lp3952_register_led_classdev(struct lp3952_led_array * priv)108 static 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
lp3952_set_pattern_gen_cmd(struct lp3952_led_array * priv,u8 cmd_index,u8 r,u8 g,u8 b,enum lp3952_tt tt,enum lp3952_cet cet)146 static 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
lp3952_configure(struct lp3952_led_array * priv)177 static 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
203 static 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
lp3952_probe(struct i2c_client * client)210 static int lp3952_probe(struct i2c_client *client)
211 {
212 int status;
213 struct lp3952_led_array *priv;
214
215 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
216 if (!priv)
217 return -ENOMEM;
218
219 priv->client = client;
220
221 priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",
222 GPIOD_OUT_HIGH);
223 if (IS_ERR(priv->enable_gpio)) {
224 status = PTR_ERR(priv->enable_gpio);
225 dev_err(&client->dev, "Failed to enable gpio: %d\n", status);
226 return status;
227 }
228
229 priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);
230 if (IS_ERR(priv->regmap)) {
231 int err = PTR_ERR(priv->regmap);
232
233 dev_err(&client->dev, "Failed to allocate register map: %d\n",
234 err);
235 return err;
236 }
237
238 i2c_set_clientdata(client, priv);
239
240 status = lp3952_configure(priv);
241 if (status) {
242 dev_err(&client->dev, "Probe failed. Device not found (%d)\n",
243 status);
244 return status;
245 }
246
247 status = lp3952_register_led_classdev(priv);
248 if (status) {
249 dev_err(&client->dev, "Unable to register led_classdev: %d\n",
250 status);
251 return status;
252 }
253
254 return 0;
255 }
256
lp3952_remove(struct i2c_client * client)257 static void lp3952_remove(struct i2c_client *client)
258 {
259 struct lp3952_led_array *priv;
260
261 priv = i2c_get_clientdata(client);
262 lp3952_on_off(priv, LP3952_LED_ALL, false);
263 gpiod_set_value(priv->enable_gpio, 0);
264 }
265
266 static const struct i2c_device_id lp3952_id[] = {
267 {LP3952_NAME, 0},
268 {}
269 };
270 MODULE_DEVICE_TABLE(i2c, lp3952_id);
271
272 static struct i2c_driver lp3952_i2c_driver = {
273 .driver = {
274 .name = LP3952_NAME,
275 },
276 .probe = lp3952_probe,
277 .remove = lp3952_remove,
278 .id_table = lp3952_id,
279 };
280
281 module_i2c_driver(lp3952_i2c_driver);
282
283 MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
284 MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
285 MODULE_LICENSE("GPL v2");
286
