aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-lp8788.c
blob: 9b9525ccca1573999288ced7ef88e841e300d4b3 (plain) (blame)
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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * TI LP8788 MFD - keyled driver
 *
 * Copyright 2012 Texas Instruments
 *
 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/mutex.h>
#include <linux/mfd/lp8788.h>
#include <linux/mfd/lp8788-isink.h>

#define MAX_BRIGHTNESS			LP8788_ISINK_MAX_PWM
#define DEFAULT_LED_NAME		"keyboard-backlight"

struct lp8788_led {
	struct lp8788 *lp;
	struct mutex lock;
	struct led_classdev led_dev;
	enum lp8788_isink_number isink_num;
	int on;
};

struct lp8788_led_config {
	enum lp8788_isink_scale scale;
	enum lp8788_isink_number num;
	int iout;
};

static struct lp8788_led_config default_led_config = {
	.scale = LP8788_ISINK_SCALE_100mA,
	.num   = LP8788_ISINK_3,
	.iout  = 0,
};

static int lp8788_led_init_device(struct lp8788_led *led,
				struct lp8788_led_platform_data *pdata)
{
	struct lp8788_led_config *cfg = &default_led_config;
	u8 addr, mask, val;
	int ret;

	if (pdata) {
		cfg->scale = pdata->scale;
		cfg->num = pdata->num;
		cfg->iout = pdata->iout_code;
	}

	led->isink_num = cfg->num;

	/* scale configuration */
	addr = LP8788_ISINK_CTRL;
	mask = 1 << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
	val = cfg->scale << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
	ret = lp8788_update_bits(led->lp, addr, mask, val);
	if (ret)
		return ret;

	/* current configuration */
	addr = lp8788_iout_addr[cfg->num];
	mask = lp8788_iout_mask[cfg->num];
	val = cfg->iout;

	return lp8788_update_bits(led->lp, addr, mask, val);
}

static int lp8788_led_enable(struct lp8788_led *led,
			enum lp8788_isink_number num, int on)
{
	int ret;

	u8 mask = 1 << num;
	u8 val = on << num;

	ret = lp8788_update_bits(led->lp, LP8788_ISINK_CTRL, mask, val);
	if (ret == 0)
		led->on = on;

	return ret;
}

static int lp8788_brightness_set(struct led_classdev *led_cdev,
				enum led_brightness val)
{
	struct lp8788_led *led =
			container_of(led_cdev, struct lp8788_led, led_dev);

	enum lp8788_isink_number num = led->isink_num;
	int enable, ret;

	mutex_lock(&led->lock);

	switch (num) {
	case LP8788_ISINK_1:
	case LP8788_ISINK_2:
	case LP8788_ISINK_3:
		ret = lp8788_write_byte(led->lp, lp8788_pwm_addr[num], val);
		if (ret < 0)
			goto unlock;
		break;
	default:
		mutex_unlock(&led->lock);
		return -EINVAL;
	}

	enable = (val > 0) ? 1 : 0;
	if (enable != led->on)
		ret = lp8788_led_enable(led, num, enable);
unlock:
	mutex_unlock(&led->lock);
	return ret;
}

static int lp8788_led_probe(struct platform_device *pdev)
{
	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
	struct lp8788_led_platform_data *led_pdata;
	struct lp8788_led *led;
	struct device *dev = &pdev->dev;
	int ret;

	led = devm_kzalloc(dev, sizeof(struct lp8788_led), GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	led->lp = lp;
	led->led_dev.max_brightness = MAX_BRIGHTNESS;
	led->led_dev.brightness_set_blocking = lp8788_brightness_set;

	led_pdata = lp->pdata ? lp->pdata->led_pdata : NULL;

	if (!led_pdata || !led_pdata->name)
		led->led_dev.name = DEFAULT_LED_NAME;
	else
		led->led_dev.name = led_pdata->name;

	mutex_init(&led->lock);

	ret = lp8788_led_init_device(led, led_pdata);
	if (ret) {
		dev_err(dev, "led init device err: %d\n", ret);
		return ret;
	}

	ret = devm_led_classdev_register(dev, &led->led_dev);
	if (ret) {
		dev_err(dev, "led register err: %d\n", ret);
		return ret;
	}

	return 0;
}

static struct platform_driver lp8788_led_driver = {
	.probe = lp8788_led_probe,
	.driver = {
		.name = LP8788_DEV_KEYLED,
	},
};
module_platform_driver(lp8788_led_driver);

MODULE_DESCRIPTION("Texas Instruments LP8788 Keyboard LED Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lp8788-keyled");