1 /*
2 * LED driver for TI lp3952 controller
3 *
4 * Copyright (C) 2016, DAQRI, LLC.
5 * Author: Tony Makkiel <tony.makkiel@daqri.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13 #include <linux/acpi.h>
14 #include <linux/delay.h>
15 #include <linux/gpio.h>
16 #include <linux/i2c.h>
17 #include <linux/io.h>
18 #include <linux/kernel.h>
19 #include <linux/leds.h>
20 #include <linux/leds-lp3952.h>
21 #include <linux/module.h>
22 #include <linux/notifier.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm.h>
25 #include <linux/reboot.h>
26 #include <linux/regmap.h>
27
lp3952_register_write(struct i2c_client * client,u8 reg,u8 val)28 static int lp3952_register_write(struct i2c_client *client, u8 reg, u8 val)
29 {
30 int ret;
31 struct lp3952_led_array *priv = i2c_get_clientdata(client);
32
33 ret = regmap_write(priv->regmap, reg, val);
34
35 if (ret)
36 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
37 __func__, reg, val, ret);
38 return ret;
39 }
40
lp3952_on_off(struct lp3952_led_array * priv,enum lp3952_leds led_id,bool on)41 static void lp3952_on_off(struct lp3952_led_array *priv,
42 enum lp3952_leds led_id, bool on)
43 {
44 int ret, val;
45
46 dev_dbg(&priv->client->dev, "%s LED %d to %d\n", __func__, led_id, on);
47
48 val = 1 << led_id;
49 if (led_id == LP3952_LED_ALL)
50 val = LP3952_LED_MASK_ALL;
51
52 ret = regmap_update_bits(priv->regmap, LP3952_REG_LED_CTRL, val,
53 on ? val : 0);
54 if (ret)
55 dev_err(&priv->client->dev, "%s, Error %d\n", __func__, ret);
56 }
57
58 /*
59 * Using Imax to control brightness. There are 4 possible
60 * setting 25, 50, 75 and 100 % of Imax. Possible values are
61 * values 0-4. 0 meaning turn off.
62 */
lp3952_set_brightness(struct led_classdev * cdev,enum led_brightness value)63 static int lp3952_set_brightness(struct led_classdev *cdev,
64 enum led_brightness value)
65 {
66 unsigned int reg, shift_val;
67 struct lp3952_ctrl_hdl *led = container_of(cdev,
68 struct lp3952_ctrl_hdl,
69 cdev);
70 struct lp3952_led_array *priv = (struct lp3952_led_array *)led->priv;
71
72 dev_dbg(cdev->dev, "Brightness request: %d on %d\n", value,
73 led->channel);
74
75 if (value == LED_OFF) {
76 lp3952_on_off(priv, led->channel, false);
77 return 0;
78 }
79
80 if (led->channel > LP3952_RED_1) {
81 dev_err(cdev->dev, " %s Invalid LED requested", __func__);
82 return -EINVAL;
83 }
84
85 if (led->channel >= LP3952_BLUE_1) {
86 reg = LP3952_REG_RGB1_MAX_I_CTRL;
87 shift_val = (led->channel - LP3952_BLUE_1) * 2;
88 } else {
89 reg = LP3952_REG_RGB2_MAX_I_CTRL;
90 shift_val = led->channel * 2;
91 }
92
93 /* Enable the LED in case it is not enabled already */
94 lp3952_on_off(priv, led->channel, true);
95
96 return regmap_update_bits(priv->regmap, reg, 3 << shift_val,
97 --value << shift_val);
98 }
99
lp3952_get_label(struct device * dev,const char * label,char * dest)100 static int lp3952_get_label(struct device *dev, const char *label, char *dest)
101 {
102 int ret;
103 const char *str;
104
105 ret = device_property_read_string(dev, label, &str);
106 if (!ret)
107 strncpy(dest, str, LP3952_LABEL_MAX_LEN);
108
109 return ret;
110 }
111
lp3952_register_led_classdev(struct lp3952_led_array * priv)112 static int lp3952_register_led_classdev(struct lp3952_led_array *priv)
113 {
114 int i, acpi_ret, ret = -ENODEV;
115 static const char *led_name_hdl[LP3952_LED_ALL] = {
116 "blue2",
117 "green2",
118 "red2",
119 "blue1",
120 "green1",
121 "red1"
122 };
123
124 for (i = 0; i < LP3952_LED_ALL; i++) {
125 acpi_ret = lp3952_get_label(&priv->client->dev, led_name_hdl[i],
126 priv->leds[i].name);
127 if (acpi_ret)
128 continue;
129
130 priv->leds[i].cdev.name = priv->leds[i].name;
131 priv->leds[i].cdev.brightness = LED_OFF;
132 priv->leds[i].cdev.max_brightness = LP3952_BRIGHT_MAX;
133 priv->leds[i].cdev.brightness_set_blocking =
134 lp3952_set_brightness;
135 priv->leds[i].channel = i;
136 priv->leds[i].priv = priv;
137
138 ret = devm_led_classdev_register(&priv->client->dev,
139 &priv->leds[i].cdev);
140 if (ret < 0) {
141 dev_err(&priv->client->dev,
142 "couldn't register LED %s\n",
143 priv->leds[i].cdev.name);
144 break;
145 }
146 }
147 return ret;
148 }
149
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)150 static int lp3952_set_pattern_gen_cmd(struct lp3952_led_array *priv,
151 u8 cmd_index, u8 r, u8 g, u8 b,
152 enum lp3952_tt tt, enum lp3952_cet cet)
153 {
154 int ret;
155 struct ptrn_gen_cmd line = {
156 {
157 {
158 .r = r,
159 .g = g,
160 .b = b,
161 .cet = cet,
162 .tt = tt
163 }
164 }
165 };
166
167 if (cmd_index >= LP3952_CMD_REG_COUNT)
168 return -EINVAL;
169
170 ret = lp3952_register_write(priv->client,
171 LP3952_REG_CMD_0 + cmd_index * 2,
172 line.bytes.msb);
173 if (ret)
174 return ret;
175
176 return lp3952_register_write(priv->client,
177 LP3952_REG_CMD_0 + cmd_index * 2 + 1,
178 line.bytes.lsb);
179 }
180
lp3952_configure(struct lp3952_led_array * priv)181 static int lp3952_configure(struct lp3952_led_array *priv)
182 {
183 int ret;
184
185 /* Disable any LEDs on from any previous conf. */
186 ret = lp3952_register_write(priv->client, LP3952_REG_LED_CTRL, 0);
187 if (ret)
188 return ret;
189
190 /* enable rgb patter, loop */
191 ret = lp3952_register_write(priv->client, LP3952_REG_PAT_GEN_CTRL,
192 LP3952_PATRN_LOOP | LP3952_PATRN_GEN_EN);
193 if (ret)
194 return ret;
195
196 /* Update Bit 6 (Active mode), Select both Led sets, Bit [1:0] */
197 ret = lp3952_register_write(priv->client, LP3952_REG_ENABLES,
198 LP3952_ACTIVE_MODE | LP3952_INT_B00ST_LDR);
199 if (ret)
200 return ret;
201
202 /* Set Cmd1 for RGB intensity,cmd and transition time */
203 return lp3952_set_pattern_gen_cmd(priv, 0, I46, I71, I100, TT0,
204 CET197);
205 }
206
207 static const struct regmap_config lp3952_regmap = {
208 .reg_bits = 8,
209 .val_bits = 8,
210 .max_register = REG_MAX,
211 .cache_type = REGCACHE_RBTREE,
212 };
213
lp3952_probe(struct i2c_client * client,const struct i2c_device_id * id)214 static int lp3952_probe(struct i2c_client *client,
215 const struct i2c_device_id *id)
216 {
217 int status;
218 struct lp3952_led_array *priv;
219
220 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
221 if (!priv)
222 return -ENOMEM;
223
224 priv->client = client;
225
226 priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",
227 GPIOD_OUT_HIGH);
228 if (IS_ERR(priv->enable_gpio)) {
229 status = PTR_ERR(priv->enable_gpio);
230 dev_err(&client->dev, "Failed to enable gpio: %d\n", status);
231 return status;
232 }
233
234 priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);
235 if (IS_ERR(priv->regmap)) {
236 int err = PTR_ERR(priv->regmap);
237
238 dev_err(&client->dev, "Failed to allocate register map: %d\n",
239 err);
240 return err;
241 }
242
243 i2c_set_clientdata(client, priv);
244
245 status = lp3952_configure(priv);
246 if (status) {
247 dev_err(&client->dev, "Probe failed. Device not found (%d)\n",
248 status);
249 return status;
250 }
251
252 status = lp3952_register_led_classdev(priv);
253 if (status) {
254 dev_err(&client->dev, "Unable to register led_classdev: %d\n",
255 status);
256 return status;
257 }
258
259 return 0;
260 }
261
lp3952_remove(struct i2c_client * client)262 static int lp3952_remove(struct i2c_client *client)
263 {
264 struct lp3952_led_array *priv;
265
266 priv = i2c_get_clientdata(client);
267 lp3952_on_off(priv, LP3952_LED_ALL, false);
268 gpiod_set_value(priv->enable_gpio, 0);
269
270 return 0;
271 }
272
273 static const struct i2c_device_id lp3952_id[] = {
274 {LP3952_NAME, 0},
275 {}
276 };
277
278 #ifdef CONFIG_ACPI
279 static const struct acpi_device_id lp3952_acpi_match[] = {
280 {"TXNW3952", 0},
281 {}
282 };
283
284 MODULE_DEVICE_TABLE(acpi, lp3952_acpi_match);
285 #endif
286
287 static struct i2c_driver lp3952_i2c_driver = {
288 .driver = {
289 .name = LP3952_NAME,
290 .acpi_match_table = ACPI_PTR(lp3952_acpi_match),
291 },
292 .probe = lp3952_probe,
293 .remove = lp3952_remove,
294 .id_table = lp3952_id,
295 };
296
297 module_i2c_driver(lp3952_i2c_driver);
298
299 MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
300 MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
301 MODULE_LICENSE("GPL v2");
302