xref: /openbmc/linux/drivers/video/backlight/l4f00242t03.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 
25 struct 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 
34 static 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 
47 static 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 
70 static 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 <= FB_BLANK_NORMAL) {
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 
108 static struct lcd_ops l4f_ops = {
109 	.set_power	= l4f00242t03_lcd_power_set,
110 	.get_power	= NULL,
111 };
112 
113 static 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 
196 err5:
197 	if (priv->core_reg)
198 		regulator_put(priv->core_reg);
199 err4:
200 	if (priv->io_reg)
201 		regulator_put(priv->io_reg);
202 err3:
203 	gpio_free(pdata->data_enable_gpio);
204 err2:
205 	gpio_free(pdata->reset_gpio);
206 err:
207 	kfree(priv);
208 
209 	return ret;
210 }
211 
212 static 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 
233 static 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 
242 static __init int l4f00242t03_init(void)
243 {
244 	return spi_register_driver(&l4f00242t03_driver);
245 }
246 
247 static __exit void l4f00242t03_exit(void)
248 {
249 	spi_unregister_driver(&l4f00242t03_driver);
250 }
251 
252 module_init(l4f00242t03_init);
253 module_exit(l4f00242t03_exit);
254 
255 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
256 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");
257 MODULE_LICENSE("GPL v2");
258