summaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-sgm3140.c
blob: f4f831570f11c442b8b4c9887fc482c6c15678f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2020 Luca Weiss <luca@z3ntu.xyz>

#include <linux/gpio/consumer.h>
#include <linux/led-class-flash.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <linux/platform_device.h>

#include <media/v4l2-flash-led-class.h>

#define FLASH_TIMEOUT_DEFAULT		250000U /* 250ms */
#define FLASH_MAX_TIMEOUT_DEFAULT	300000U /* 300ms */

struct sgm3140 {
	struct led_classdev_flash fled_cdev;
	struct v4l2_flash *v4l2_flash;

	struct timer_list powerdown_timer;

	struct gpio_desc *flash_gpio;
	struct gpio_desc *enable_gpio;
	struct regulator *vin_regulator;

	bool enabled;

	/* current timeout in us */
	u32 timeout;
	/* maximum timeout in us */
	u32 max_timeout;
};

static struct sgm3140 *flcdev_to_sgm3140(struct led_classdev_flash *flcdev)
{
	return container_of(flcdev, struct sgm3140, fled_cdev);
}

static int sgm3140_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
{
	struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
	int ret;

	if (priv->enabled == state)
		return 0;

	if (state) {
		ret = regulator_enable(priv->vin_regulator);
		if (ret) {
			dev_err(fled_cdev->led_cdev.dev,
				"failed to enable regulator: %d\n", ret);
			return ret;
		}
		gpiod_set_value_cansleep(priv->flash_gpio, 1);
		gpiod_set_value_cansleep(priv->enable_gpio, 1);
		mod_timer(&priv->powerdown_timer,
			  jiffies + usecs_to_jiffies(priv->timeout));
	} else {
		del_timer_sync(&priv->powerdown_timer);
		gpiod_set_value_cansleep(priv->enable_gpio, 0);
		gpiod_set_value_cansleep(priv->flash_gpio, 0);
		ret = regulator_disable(priv->vin_regulator);
		if (ret) {
			dev_err(fled_cdev->led_cdev.dev,
				"failed to disable regulator: %d\n", ret);
			return ret;
		}
	}

	priv->enabled = state;

	return 0;
}

static int sgm3140_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
{
	struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);

	*state = timer_pending(&priv->powerdown_timer);

	return 0;
}

static int sgm3140_timeout_set(struct led_classdev_flash *fled_cdev,
			       u32 timeout)
{
	struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);

	priv->timeout = timeout;

	return 0;
}

static const struct led_flash_ops sgm3140_flash_ops = {
	.strobe_set = sgm3140_strobe_set,
	.strobe_get = sgm3140_strobe_get,
	.timeout_set = sgm3140_timeout_set,
};

static int sgm3140_brightness_set(struct led_classdev *led_cdev,
				  enum led_brightness brightness)
{
	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
	struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
	bool enable = brightness == LED_ON;
	int ret;

	if (priv->enabled == enable)
		return 0;

	if (enable) {
		ret = regulator_enable(priv->vin_regulator);
		if (ret) {
			dev_err(led_cdev->dev,
				"failed to enable regulator: %d\n", ret);
			return ret;
		}
		gpiod_set_value_cansleep(priv->enable_gpio, 1);
	} else {
		gpiod_set_value_cansleep(priv->enable_gpio, 0);
		ret = regulator_disable(priv->vin_regulator);
		if (ret) {
			dev_err(led_cdev->dev,
				"failed to disable regulator: %d\n", ret);
			return ret;
		}
	}

	priv->enabled = enable;

	return 0;
}

static void sgm3140_powerdown_timer(struct timer_list *t)
{
	struct sgm3140 *priv = from_timer(priv, t, powerdown_timer);

	gpiod_set_value(priv->enable_gpio, 0);
	gpiod_set_value(priv->flash_gpio, 0);
	regulator_disable(priv->vin_regulator);

	priv->enabled = false;
}

static void sgm3140_init_flash_timeout(struct sgm3140 *priv)
{
	struct led_classdev_flash *fled_cdev = &priv->fled_cdev;
	struct led_flash_setting *s;

	/* Init flash timeout setting */
	s = &fled_cdev->timeout;
	s->min = 1;
	s->max = priv->max_timeout;
	s->step = 1;
	s->val = FLASH_TIMEOUT_DEFAULT;
}

#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv,
					struct v4l2_flash_config *v4l2_sd_cfg)
{
	struct led_classdev *led_cdev = &priv->fled_cdev.led_cdev;
	struct led_flash_setting *s;

	strscpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name,
		sizeof(v4l2_sd_cfg->dev_name));

	/* Init flash intensity setting */
	s = &v4l2_sd_cfg->intensity;
	s->min = 0;
	s->max = 1;
	s->step = 1;
	s->val = 1;
}

#else
static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv,
					struct v4l2_flash_config *v4l2_sd_cfg)
{
}
#endif

static int sgm3140_probe(struct platform_device *pdev)
{
	struct sgm3140 *priv;
	struct led_classdev *led_cdev;
	struct led_classdev_flash *fled_cdev;
	struct led_init_data init_data = {};
	struct fwnode_handle *child_node;
	struct v4l2_flash_config v4l2_sd_cfg = {};
	int ret;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->flash_gpio = devm_gpiod_get(&pdev->dev, "flash", GPIOD_OUT_LOW);
	ret = PTR_ERR_OR_ZERO(priv->flash_gpio);
	if (ret)
		return dev_err_probe(&pdev->dev, ret,
				     "Failed to request flash gpio\n");

	priv->enable_gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
	ret = PTR_ERR_OR_ZERO(priv->enable_gpio);
	if (ret)
		return dev_err_probe(&pdev->dev, ret,
				     "Failed to request enable gpio\n");

	priv->vin_regulator = devm_regulator_get(&pdev->dev, "vin");
	ret = PTR_ERR_OR_ZERO(priv->vin_regulator);
	if (ret)
		return dev_err_probe(&pdev->dev, ret,
				     "Failed to request regulator\n");

	child_node = fwnode_get_next_available_child_node(pdev->dev.fwnode,
							  NULL);
	if (!child_node) {
		dev_err(&pdev->dev,
			"No fwnode child node found for connected LED.\n");
		return -EINVAL;
	}

	ret = fwnode_property_read_u32(child_node, "flash-max-timeout-us",
				       &priv->max_timeout);
	if (ret) {
		priv->max_timeout = FLASH_MAX_TIMEOUT_DEFAULT;
		dev_warn(&pdev->dev,
			 "flash-max-timeout-us property missing\n");
	}

	/*
	 * Set default timeout to FLASH_DEFAULT_TIMEOUT except if max_timeout
	 * from DT is lower.
	 */
	priv->timeout = min(priv->max_timeout, FLASH_TIMEOUT_DEFAULT);

	timer_setup(&priv->powerdown_timer, sgm3140_powerdown_timer, 0);

	fled_cdev = &priv->fled_cdev;
	led_cdev = &fled_cdev->led_cdev;

	fled_cdev->ops = &sgm3140_flash_ops;

	led_cdev->brightness_set_blocking = sgm3140_brightness_set;
	led_cdev->max_brightness = LED_ON;
	led_cdev->flags |= LED_DEV_CAP_FLASH;

	sgm3140_init_flash_timeout(priv);

	init_data.fwnode = child_node;

	platform_set_drvdata(pdev, priv);

	/* Register in the LED subsystem */
	ret = devm_led_classdev_flash_register_ext(&pdev->dev,
						   fled_cdev, &init_data);
	if (ret) {
		dev_err(&pdev->dev, "Failed to register flash device: %d\n",
			ret);
		goto err;
	}

	sgm3140_init_v4l2_flash_config(priv, &v4l2_sd_cfg);

	/* Create V4L2 Flash subdev */
	priv->v4l2_flash = v4l2_flash_init(&pdev->dev,
					   child_node,
					   fled_cdev, NULL,
					   &v4l2_sd_cfg);
	if (IS_ERR(priv->v4l2_flash)) {
		ret = PTR_ERR(priv->v4l2_flash);
		goto err;
	}

	return ret;

err:
	fwnode_handle_put(child_node);
	return ret;
}

static int sgm3140_remove(struct platform_device *pdev)
{
	struct sgm3140 *priv = platform_get_drvdata(pdev);

	del_timer_sync(&priv->powerdown_timer);

	v4l2_flash_release(priv->v4l2_flash);

	return 0;
}

static const struct of_device_id sgm3140_dt_match[] = {
	{ .compatible = "sgmicro,sgm3140" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sgm3140_dt_match);

static struct platform_driver sgm3140_driver = {
	.probe	= sgm3140_probe,
	.remove	= sgm3140_remove,
	.driver	= {
		.name	= "sgm3140",
		.of_match_table = sgm3140_dt_match,
	},
};

module_platform_driver(sgm3140_driver);

MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xyz>");
MODULE_DESCRIPTION("SG Micro SGM3140 charge pump LED driver");
MODULE_LICENSE("GPL v2");