[linux-block.git] / drivers / leds / leds-dac124s085.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2008
 * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
 *
 * LED driver for the DAC124S085 SPI DAC
 */

#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>

struct dac124s085_led {
	struct led_classdev	ldev;
	struct spi_device	*spi;
	int			id;
	char			name[sizeof("dac124s085-3")];

	struct mutex		mutex;
};

struct dac124s085 {
	struct dac124s085_led leds[4];
};

#define REG_WRITE		(0 << 12)
#define REG_WRITE_UPDATE	(1 << 12)
#define ALL_WRITE_UPDATE	(2 << 12)
#define POWER_DOWN_OUTPUT	(3 << 12)

static int dac124s085_set_brightness(struct led_classdev *ldev,
				      enum led_brightness brightness)
{
	struct dac124s085_led *led = container_of(ldev, struct dac124s085_led,
						  ldev);
	u16 word;
	int ret;

	mutex_lock(&led->mutex);
	word = cpu_to_le16(((led->id) << 14) | REG_WRITE_UPDATE |
			   (brightness & 0xfff));
	ret = spi_write(led->spi, (const u8 *)&word, sizeof(word));
	mutex_unlock(&led->mutex);

	return ret;
}

static int dac124s085_probe(struct spi_device *spi)
{
	struct dac124s085	*dac;
	struct dac124s085_led	*led;
	int i, ret;

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

	spi->bits_per_word = 16;

	for (i = 0; i < ARRAY_SIZE(dac->leds); i++) {
		led		= dac->leds + i;
		led->id		= i;
		led->spi	= spi;
		snprintf(led->name, sizeof(led->name), "dac124s085-%d", i);
		mutex_init(&led->mutex);
		led->ldev.name = led->name;
		led->ldev.brightness = LED_OFF;
		led->ldev.max_brightness = 0xfff;
		led->ldev.brightness_set_blocking = dac124s085_set_brightness;
		ret = led_classdev_register(&spi->dev, &led->ldev);
		if (ret < 0)
			goto eledcr;
	}

	spi_set_drvdata(spi, dac);

	return 0;

eledcr:
	while (i--)
		led_classdev_unregister(&dac->leds[i].ldev);

	return ret;
}

static void dac124s085_remove(struct spi_device *spi)
{
	struct dac124s085	*dac = spi_get_drvdata(spi);
	int i;

	for (i = 0; i < ARRAY_SIZE(dac->leds); i++)
		led_classdev_unregister(&dac->leds[i].ldev);
}

static struct spi_driver dac124s085_driver = {
	.probe		= dac124s085_probe,
	.remove		= dac124s085_remove,
	.driver = {
		.name	= "dac124s085",
	},
};

module_spi_driver(dac124s085_driver);

MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
MODULE_DESCRIPTION("DAC124S085 LED driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("spi:dac124s085");
Commit	Line	Data
36edc939	1	// SPDX-License-Identifier: GPL-2.0-only
ac2dd0f1 GL	2	/*
	3	* Copyright 2008
	4	* Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
	5	*
ac2dd0f1 GL	6	* LED driver for the DAC124S085 SPI DAC
	7	*/
	8
ac2dd0f1 GL	9	#include <linux/leds.h>
	10	#include <linux/module.h>
	11	#include <linux/mutex.h>
	12	#include <linux/slab.h>
ac2dd0f1 GL	13	#include <linux/spi/spi.h>
	14
	15	struct dac124s085_led {
	16	struct led_classdev ldev;
	17	struct spi_device *spi;
	18	int id;
ac2dd0f1 GL	19	char name[sizeof("dac124s085-3")];
	20
	21	struct mutex mutex;
ac2dd0f1 GL	22	};
	23
	24	struct dac124s085 {
	25	struct dac124s085_led leds[4];
	26	};
	27
	28	#define REG_WRITE (0 << 12)
	29	#define REG_WRITE_UPDATE (1 << 12)
	30	#define ALL_WRITE_UPDATE (2 << 12)
	31	#define POWER_DOWN_OUTPUT (3 << 12)
	32
8ec108c0 AL	33	static int dac124s085_set_brightness(struct led_classdev *ldev,
8ec108c0 AL	34	enum led_brightness brightness)
ac2dd0f1	35	{
8ec108c0 AL	36	struct dac124s085_led *led = container_of(ldev, struct dac124s085_led,
8ec108c0 AL	37	ldev);
ac2dd0f1	38	u16 word;
8ec108c0	39	int ret;
ac2dd0f1 GL	40
	41	mutex_lock(&led->mutex);
	42	word = cpu_to_le16(((led->id) << 14) \| REG_WRITE_UPDATE \|
8ec108c0 AL	43	(brightness & 0xfff));
8ec108c0 AL	44	ret = spi_write(led->spi, (const u8 *)&word, sizeof(word));
ac2dd0f1	45	mutex_unlock(&led->mutex);
ac2dd0f1	46
8ec108c0	47	return ret;
ac2dd0f1 GL	48	}
	49
	50	static int dac124s085_probe(struct spi_device *spi)
	51	{
	52	struct dac124s085 *dac;
	53	struct dac124s085_led *led;
	54	int i, ret;
	55
e5860312	56	dac = devm_kzalloc(&spi->dev, sizeof(*dac), GFP_KERNEL);
ac2dd0f1 GL	57	if (!dac)
	58	return -ENOMEM;
	59
	60	spi->bits_per_word = 16;
	61
	62	for (i = 0; i < ARRAY_SIZE(dac->leds); i++) {
	63	led = dac->leds + i;
	64	led->id = i;
ac2dd0f1 GL	65	led->spi = spi;
ac2dd0f1 GL	66	snprintf(led->name, sizeof(led->name), "dac124s085-%d", i);
ac2dd0f1 GL	67	mutex_init(&led->mutex);
	68	led->ldev.name = led->name;
	69	led->ldev.brightness = LED_OFF;
	70	led->ldev.max_brightness = 0xfff;
8ec108c0	71	led->ldev.brightness_set_blocking = dac124s085_set_brightness;
ac2dd0f1 GL	72	ret = led_classdev_register(&spi->dev, &led->ldev);
	73	if (ret < 0)
	74	goto eledcr;
	75	}
	76
	77	spi_set_drvdata(spi, dac);
	78
	79	return 0;
	80
	81	eledcr:
	82	while (i--)
	83	led_classdev_unregister(&dac->leds[i].ldev);
	84
ac2dd0f1 GL	85	return ret;
	86	}
	87
a0386bba	88	static void dac124s085_remove(struct spi_device *spi)
ac2dd0f1 GL	89	{
	90	struct dac124s085 *dac = spi_get_drvdata(spi);
	91	int i;
	92
8ec108c0	93	for (i = 0; i < ARRAY_SIZE(dac->leds); i++)
ac2dd0f1	94	led_classdev_unregister(&dac->leds[i].ldev);
ac2dd0f1 GL	95	}
	96
	97	static struct spi_driver dac124s085_driver = {
	98	.probe = dac124s085_probe,
	99	.remove = dac124s085_remove,
	100	.driver = {
	101	.name = "dac124s085",
ac2dd0f1 GL	102	},
	103	};
	104
19b95576	105	module_spi_driver(dac124s085_driver);
ac2dd0f1 GL	106
	107	MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
	108	MODULE_DESCRIPTION("DAC124S085 LED driver");
	109	MODULE_LICENSE("GPL v2");
e0626e38	110	MODULE_ALIAS("spi:dac124s085");