1/*
  2 * LED Driver for Dialog DA9052 PMICs.
  3 *
  4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
  5 *
  6 * Author: David Dajun Chen <dchen@diasemi.com>
  7 *
  8 *  This program is free software; you can redistribute  it and/or modify it
  9 *  under  the terms of  the GNU General  Public License as published by the
 10 *  Free Software Foundation;  either version 2 of the  License, or (at your
 11 *  option) any later version.
 12 *
 13 */
 14
 15#include <linux/module.h>
 16#include <linux/kernel.h>
 17#include <linux/platform_device.h>
 18#include <linux/leds.h>
 19#include <linux/slab.h>
 20
 21#include <linux/mfd/da9052/reg.h>
 22#include <linux/mfd/da9052/da9052.h>
 23#include <linux/mfd/da9052/pdata.h>
 24
 25#define DA9052_OPENDRAIN_OUTPUT	2
 26#define DA9052_SET_HIGH_LVL_OUTPUT	(1 << 3)
 27#define DA9052_MASK_UPPER_NIBBLE	0xF0
 28#define DA9052_MASK_LOWER_NIBBLE	0x0F
 29#define DA9052_NIBBLE_SHIFT		4
 30#define DA9052_MAX_BRIGHTNESS		0x5f
 31
 32struct da9052_led {
 33	struct led_classdev cdev;
 34	struct da9052 *da9052;
 35	unsigned char led_index;
 36	unsigned char id;
 37};
 38
 39static unsigned char led_reg[] = {
 40	DA9052_LED_CONT_4_REG,
 41	DA9052_LED_CONT_5_REG,
 42};
 43
 44static int da9052_set_led_brightness(struct da9052_led *led,
 45				     enum led_brightness brightness)
 46{
 47	u8 val;
 48	int error;
 49
 50	val = (brightness & 0x7f) | DA9052_LED_CONT_DIM;
 51
 52	error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
 53	if (error < 0)
 54		dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
 55			error);
 56	return error;
 57}
 58
 59static int da9052_led_set(struct led_classdev *led_cdev,
 60			   enum led_brightness value)
 61{
 62	struct da9052_led *led =
 63			container_of(led_cdev, struct da9052_led, cdev);
 64
 65	return da9052_set_led_brightness(led, value);
 66}
 67
 68static int da9052_configure_leds(struct da9052 *da9052)
 69{
 70	int error;
 71	unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
 72				       | DA9052_SET_HIGH_LVL_OUTPUT;
 73
 74	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
 75				  DA9052_MASK_LOWER_NIBBLE,
 76				  register_value);
 77
 78	if (error < 0) {
 79		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
 80			error);
 81		return error;
 82	}
 83
 84	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
 85				  DA9052_MASK_UPPER_NIBBLE,
 86				  register_value << DA9052_NIBBLE_SHIFT);
 87	if (error < 0)
 88		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
 89			error);
 90
 91	return error;
 92}
 93
 94static int da9052_led_probe(struct platform_device *pdev)
 95{
 96	struct da9052_pdata *pdata;
 97	struct da9052 *da9052;
 98	struct led_platform_data *pled;
 99	struct da9052_led *led = NULL;
100	int error = -ENODEV;
101	int i;
102
103	da9052 = dev_get_drvdata(pdev->dev.parent);
104	pdata = dev_get_platdata(da9052->dev);
105	if (pdata == NULL) {
106		dev_err(&pdev->dev, "No platform data\n");
107		goto err;
108	}
109
110	pled = pdata->pled;
111	if (pled == NULL) {
112		dev_err(&pdev->dev, "No platform data for LED\n");
113		goto err;
114	}
115
116	led = devm_kzalloc(&pdev->dev,
117			   sizeof(struct da9052_led) * pled->num_leds,
118			   GFP_KERNEL);
119	if (!led) {
120		error = -ENOMEM;
121		goto err;
122	}
123
124	for (i = 0; i < pled->num_leds; i++) {
125		led[i].cdev.name = pled->leds[i].name;
126		led[i].cdev.brightness_set_blocking = da9052_led_set;
127		led[i].cdev.brightness = LED_OFF;
128		led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
129		led[i].led_index = pled->leds[i].flags;
130		led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
131
132		error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
133		if (error) {
134			dev_err(&pdev->dev, "Failed to register led %d\n",
135				led[i].led_index);
136			goto err_register;
137		}
138
139		error = da9052_set_led_brightness(&led[i],
140						  led[i].cdev.brightness);
141		if (error) {
142			dev_err(&pdev->dev, "Unable to init led %d\n",
143				led[i].led_index);
144			continue;
145		}
146	}
147	error = da9052_configure_leds(led->da9052);
148	if (error) {
149		dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
150		goto err_register;
151	}
152
153	platform_set_drvdata(pdev, led);
154
155	return 0;
156
157err_register:
158	for (i = i - 1; i >= 0; i--)
159		led_classdev_unregister(&led[i].cdev);
160err:
161	return error;
162}
163
164static int da9052_led_remove(struct platform_device *pdev)
165{
166	struct da9052_led *led = platform_get_drvdata(pdev);
167	struct da9052_pdata *pdata;
168	struct da9052 *da9052;
169	struct led_platform_data *pled;
170	int i;
171
172	da9052 = dev_get_drvdata(pdev->dev.parent);
173	pdata = dev_get_platdata(da9052->dev);
174	pled = pdata->pled;
175
176	for (i = 0; i < pled->num_leds; i++) {
177		da9052_set_led_brightness(&led[i], LED_OFF);
178		led_classdev_unregister(&led[i].cdev);
179	}
180
181	return 0;
182}
183
184static struct platform_driver da9052_led_driver = {
185	.driver		= {
186		.name	= "da9052-leds",
187	},
188	.probe		= da9052_led_probe,
189	.remove		= da9052_led_remove,
190};
191
192module_platform_driver(da9052_led_driver);
193
194MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
195MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
196MODULE_LICENSE("GPL");