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	strscpy(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_MAPLE,
208};
209
210static 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
257static 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
266static const struct i2c_device_id lp3952_id[] = {
267	{LP3952_NAME, 0},
268	{}
269};
270MODULE_DEVICE_TABLE(i2c, lp3952_id);
271
272static 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
281module_i2c_driver(lp3952_i2c_driver);
282
283MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
284MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
285MODULE_LICENSE("GPL v2");