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/workqueue.h>
 20#include <linux/slab.h>
 21
 22#include <linux/mfd/da9052/reg.h>
 23#include <linux/mfd/da9052/da9052.h>
 24#include <linux/mfd/da9052/pdata.h>
 25
 26#define DA9052_OPENDRAIN_OUTPUT	2
 27#define DA9052_SET_HIGH_LVL_OUTPUT	(1 << 3)
 28#define DA9052_MASK_UPPER_NIBBLE	0xF0
 29#define DA9052_MASK_LOWER_NIBBLE	0x0F
 30#define DA9052_NIBBLE_SHIFT		4
 31#define DA9052_MAX_BRIGHTNESS		0x5f
 32
 33struct da9052_led {
 34	struct led_classdev cdev;
 35	struct work_struct work;
 36	struct da9052 *da9052;
 37	unsigned char led_index;
 38	unsigned char id;
 39	int brightness;
 40};
 41
 42static unsigned char led_reg[] = {
 43	DA9052_LED_CONT_4_REG,
 44	DA9052_LED_CONT_5_REG,
 45};
 46
 47static int da9052_set_led_brightness(struct da9052_led *led)
 48{
 49	u8 val;
 50	int error;
 51
 52	val = (led->brightness & 0x7f) | DA9052_LED_CONT_DIM;
 53
 54	error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
 55	if (error < 0)
 56		dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
 57			error);
 58	return error;
 59}
 60
 61static void da9052_led_work(struct work_struct *work)
 62{
 63	struct da9052_led *led = container_of(work, struct da9052_led, work);
 64
 65	da9052_set_led_brightness(led);
 66}
 67
 68static void da9052_led_set(struct led_classdev *led_cdev,
 69			   enum led_brightness value)
 70{
 71	struct da9052_led *led;
 72
 73	led = container_of(led_cdev, struct da9052_led, cdev);
 74	led->brightness = value;
 75	schedule_work(&led->work);
 76}
 77
 78static int da9052_configure_leds(struct da9052 *da9052)
 79{
 80	int error;
 81	unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
 82				       | DA9052_SET_HIGH_LVL_OUTPUT;
 83
 84	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
 85				  DA9052_MASK_LOWER_NIBBLE,
 86				  register_value);
 87
 88	if (error < 0) {
 89		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
 90			error);
 91		return error;
 92	}
 93
 94	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
 95				  DA9052_MASK_UPPER_NIBBLE,
 96				  register_value << DA9052_NIBBLE_SHIFT);
 97	if (error < 0)
 98		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
 99			error);
100
101	return error;
102}
103
104static int da9052_led_probe(struct platform_device *pdev)
105{
106	struct da9052_pdata *pdata;
107	struct da9052 *da9052;
108	struct led_platform_data *pled;
109	struct da9052_led *led = NULL;
110	int error = -ENODEV;
111	int i;
112
113	da9052 = dev_get_drvdata(pdev->dev.parent);
114	pdata = dev_get_platdata(da9052->dev);
115	if (pdata == NULL) {
116		dev_err(&pdev->dev, "No platform data\n");
117		goto err;
118	}
119
120	pled = pdata->pled;
121	if (pled == NULL) {
122		dev_err(&pdev->dev, "No platform data for LED\n");
123		goto err;
124	}
125
126	led = devm_kzalloc(&pdev->dev,
127			   sizeof(struct da9052_led) * pled->num_leds,
128			   GFP_KERNEL);
129	if (led == NULL) {
130		dev_err(&pdev->dev, "Failed to alloc memory\n");
131		error = -ENOMEM;
132		goto err;
133	}
134
135	for (i = 0; i < pled->num_leds; i++) {
136		led[i].cdev.name = pled->leds[i].name;
137		led[i].cdev.brightness_set = da9052_led_set;
138		led[i].cdev.brightness = LED_OFF;
139		led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
140		led[i].brightness = LED_OFF;
141		led[i].led_index = pled->leds[i].flags;
142		led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
143		INIT_WORK(&led[i].work, da9052_led_work);
144
145		error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
146		if (error) {
147			dev_err(&pdev->dev, "Failed to register led %d\n",
148				led[i].led_index);
149			goto err_register;
150		}
151
152		error = da9052_set_led_brightness(&led[i]);
153		if (error) {
154			dev_err(&pdev->dev, "Unable to init led %d\n",
155				led[i].led_index);
156			continue;
157		}
158	}
159	error = da9052_configure_leds(led->da9052);
160	if (error) {
161		dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
162		goto err_register;
163	}
164
165	platform_set_drvdata(pdev, led);
166
167	return 0;
168
169err_register:
170	for (i = i - 1; i >= 0; i--) {
171		led_classdev_unregister(&led[i].cdev);
172		cancel_work_sync(&led[i].work);
173	}
174err:
175	return error;
176}
177
178static int da9052_led_remove(struct platform_device *pdev)
179{
180	struct da9052_led *led = platform_get_drvdata(pdev);
181	struct da9052_pdata *pdata;
182	struct da9052 *da9052;
183	struct led_platform_data *pled;
184	int i;
185
186	da9052 = dev_get_drvdata(pdev->dev.parent);
187	pdata = dev_get_platdata(da9052->dev);
188	pled = pdata->pled;
189
190	for (i = 0; i < pled->num_leds; i++) {
191		led[i].brightness = 0;
192		da9052_set_led_brightness(&led[i]);
193		led_classdev_unregister(&led[i].cdev);
194		cancel_work_sync(&led[i].work);
195	}
196
197	return 0;
198}
199
200static struct platform_driver da9052_led_driver = {
201	.driver		= {
202		.name	= "da9052-leds",
203		.owner	= THIS_MODULE,
204	},
205	.probe		= da9052_led_probe,
206	.remove		= da9052_led_remove,
207};
208
209module_platform_driver(da9052_led_driver);
210
211MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
212MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
213MODULE_LICENSE("GPL");