• Home
  • History
  • Annotate
  • Line#
  • Navigate
  • Raw
  • Download
  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/video/backlight/
1/*
2 * l4f00242t03.c -- support for Epson L4F00242T03 LCD
3 *
4 * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved.
5 *
6 * Copyright (c) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com>
7 * 	Inspired by Marek Vasut work in l4f00242t03.c
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/device.h>
15#include <linux/kernel.h>
16#include <linux/delay.h>
17#include <linux/gpio.h>
18#include <linux/lcd.h>
19#include <linux/slab.h>
20#include <linux/regulator/consumer.h>
21
22#include <linux/spi/spi.h>
23#include <linux/spi/l4f00242t03.h>
24
25struct l4f00242t03_priv {
26	struct spi_device	*spi;
27	struct lcd_device	*ld;
28	int lcd_on:1;
29	struct regulator *io_reg;
30	struct regulator *core_reg;
31};
32
33
34static void l4f00242t03_reset(unsigned int gpio)
35{
36	pr_debug("l4f00242t03_reset.\n");
37	gpio_set_value(gpio, 1);
38	mdelay(100);
39	gpio_set_value(gpio, 0);
40	mdelay(10);	/* tRES >= 100us */
41	gpio_set_value(gpio, 1);
42	mdelay(20);
43}
44
45#define param(x) ((x) | 0x100)
46
47static void l4f00242t03_lcd_init(struct spi_device *spi)
48{
49	struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
50	struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
51	const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) };
52
53	dev_dbg(&spi->dev, "initializing LCD\n");
54
55	if (priv->io_reg) {
56		regulator_set_voltage(priv->io_reg, 1800000, 1800000);
57		regulator_enable(priv->io_reg);
58	}
59
60	if (priv->core_reg) {
61		regulator_set_voltage(priv->core_reg, 2800000, 2800000);
62		regulator_enable(priv->core_reg);
63	}
64
65	gpio_set_value(pdata->data_enable_gpio, 1);
66	msleep(60);
67	spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16));
68}
69
70static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
71{
72	struct l4f00242t03_priv *priv = lcd_get_data(ld);
73	struct spi_device *spi = priv->spi;
74
75	const u16 slpout = 0x11;
76	const u16 dison = 0x29;
77
78	const u16 slpin = 0x10;
79	const u16 disoff = 0x28;
80
81	if (power) {
82		if (priv->lcd_on)
83			return 0;
84
85		dev_dbg(&spi->dev, "turning on LCD\n");
86
87		spi_write(spi, (const u8 *)&slpout, sizeof(u16));
88		msleep(60);
89		spi_write(spi, (const u8 *)&dison, sizeof(u16));
90
91		priv->lcd_on = 1;
92	} else {
93		if (!priv->lcd_on)
94			return 0;
95
96		dev_dbg(&spi->dev, "turning off LCD\n");
97
98		spi_write(spi, (const u8 *)&disoff, sizeof(u16));
99		msleep(60);
100		spi_write(spi, (const u8 *)&slpin, sizeof(u16));
101
102		priv->lcd_on = 0;
103	}
104
105	return 0;
106}
107
108static struct lcd_ops l4f_ops = {
109	.set_power	= l4f00242t03_lcd_power_set,
110	.get_power	= NULL,
111};
112
113static int __devinit l4f00242t03_probe(struct spi_device *spi)
114{
115	struct l4f00242t03_priv *priv;
116	struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
117	int ret;
118
119	if (pdata == NULL) {
120		dev_err(&spi->dev, "Uninitialized platform data.\n");
121		return -EINVAL;
122	}
123
124	priv = kzalloc(sizeof(struct l4f00242t03_priv), GFP_KERNEL);
125
126	if (priv == NULL) {
127		dev_err(&spi->dev, "No memory for this device.\n");
128		return -ENOMEM;
129	}
130
131	dev_set_drvdata(&spi->dev, priv);
132	spi->bits_per_word = 9;
133	spi_setup(spi);
134
135	priv->spi = spi;
136
137	ret = gpio_request(pdata->reset_gpio, "lcd l4f00242t03 reset");
138	if (ret) {
139		dev_err(&spi->dev,
140			"Unable to get the lcd l4f00242t03 reset gpio.\n");
141		goto err;
142	}
143
144	ret = gpio_direction_output(pdata->reset_gpio, 1);
145	if (ret)
146		goto err2;
147
148	ret = gpio_request(pdata->data_enable_gpio,
149				"lcd l4f00242t03 data enable");
150	if (ret) {
151		dev_err(&spi->dev,
152			"Unable to get the lcd l4f00242t03 data en gpio.\n");
153		goto err2;
154	}
155
156	ret = gpio_direction_output(pdata->data_enable_gpio, 0);
157	if (ret)
158		goto err3;
159
160	if (pdata->io_supply) {
161		priv->io_reg = regulator_get(NULL, pdata->io_supply);
162
163		if (IS_ERR(priv->io_reg)) {
164			pr_err("%s: Unable to get the IO regulator\n",
165								__func__);
166			goto err3;
167		}
168	}
169
170	if (pdata->core_supply) {
171		priv->core_reg = regulator_get(NULL, pdata->core_supply);
172
173		if (IS_ERR(priv->core_reg)) {
174			pr_err("%s: Unable to get the core regulator\n",
175								__func__);
176			goto err4;
177		}
178	}
179
180	priv->ld = lcd_device_register("l4f00242t03",
181					&spi->dev, priv, &l4f_ops);
182	if (IS_ERR(priv->ld)) {
183		ret = PTR_ERR(priv->ld);
184		goto err5;
185	}
186
187	/* Init the LCD */
188	l4f00242t03_reset(pdata->reset_gpio);
189	l4f00242t03_lcd_init(spi);
190	l4f00242t03_lcd_power_set(priv->ld, 1);
191
192	dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");
193
194	return 0;
195
196err5:
197	if (priv->core_reg)
198		regulator_put(priv->core_reg);
199err4:
200	if (priv->io_reg)
201		regulator_put(priv->io_reg);
202err3:
203	gpio_free(pdata->data_enable_gpio);
204err2:
205	gpio_free(pdata->reset_gpio);
206err:
207	kfree(priv);
208
209	return ret;
210}
211
212static int __devexit l4f00242t03_remove(struct spi_device *spi)
213{
214	struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
215	struct l4f00242t03_pdata *pdata = priv->spi->dev.platform_data;
216
217	l4f00242t03_lcd_power_set(priv->ld, 0);
218	lcd_device_unregister(priv->ld);
219
220	gpio_free(pdata->data_enable_gpio);
221	gpio_free(pdata->reset_gpio);
222
223	if (priv->io_reg)
224		regulator_put(priv->io_reg);
225	if (priv->core_reg)
226		regulator_put(priv->core_reg);
227
228	kfree(priv);
229
230	return 0;
231}
232
233static struct spi_driver l4f00242t03_driver = {
234	.driver = {
235		.name	= "l4f00242t03",
236		.owner	= THIS_MODULE,
237	},
238	.probe		= l4f00242t03_probe,
239	.remove		= __devexit_p(l4f00242t03_remove),
240};
241
242static __init int l4f00242t03_init(void)
243{
244	return spi_register_driver(&l4f00242t03_driver);
245}
246
247static __exit void l4f00242t03_exit(void)
248{
249	spi_unregister_driver(&l4f00242t03_driver);
250}
251
252module_init(l4f00242t03_init);
253module_exit(l4f00242t03_exit);
254
255MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
256MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");
257MODULE_LICENSE("GPL v2");
258