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/module.h>
18 #include <linux/gpio.h>
19 #include <linux/lcd.h>
20 #include <linux/slab.h>
21 #include <linux/regulator/consumer.h>
22
23 #include <linux/spi/spi.h>
24 #include <linux/spi/l4f00242t03.h>
25
26 struct l4f00242t03_priv {
27 struct spi_device *spi;
28 struct lcd_device *ld;
29 int lcd_state;
30 struct regulator *io_reg;
31 struct regulator *core_reg;
32 };
33
34
l4f00242t03_reset(unsigned int gpio)35 static void l4f00242t03_reset(unsigned int gpio)
36 {
37 pr_debug("l4f00242t03_reset.\n");
38 gpio_set_value(gpio, 1);
39 mdelay(100);
40 gpio_set_value(gpio, 0);
41 mdelay(10); /* tRES >= 100us */
42 gpio_set_value(gpio, 1);
43 mdelay(20);
44 }
45
46 #define param(x) ((x) | 0x100)
47
l4f00242t03_lcd_init(struct spi_device * spi)48 static void l4f00242t03_lcd_init(struct spi_device *spi)
49 {
50 struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
51 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
52 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) };
53
54 dev_dbg(&spi->dev, "initializing LCD\n");
55
56 regulator_set_voltage(priv->io_reg, 1800000, 1800000);
57 regulator_enable(priv->io_reg);
58
59 regulator_set_voltage(priv->core_reg, 2800000, 2800000);
60 regulator_enable(priv->core_reg);
61
62 l4f00242t03_reset(pdata->reset_gpio);
63
64 gpio_set_value(pdata->data_enable_gpio, 1);
65 msleep(60);
66 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16));
67 }
68
l4f00242t03_lcd_powerdown(struct spi_device * spi)69 static void l4f00242t03_lcd_powerdown(struct spi_device *spi)
70 {
71 struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
72 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
73
74 dev_dbg(&spi->dev, "Powering down LCD\n");
75
76 gpio_set_value(pdata->data_enable_gpio, 0);
77
78 regulator_disable(priv->io_reg);
79 regulator_disable(priv->core_reg);
80 }
81
l4f00242t03_lcd_power_get(struct lcd_device * ld)82 static int l4f00242t03_lcd_power_get(struct lcd_device *ld)
83 {
84 struct l4f00242t03_priv *priv = lcd_get_data(ld);
85
86 return priv->lcd_state;
87 }
88
l4f00242t03_lcd_power_set(struct lcd_device * ld,int power)89 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
90 {
91 struct l4f00242t03_priv *priv = lcd_get_data(ld);
92 struct spi_device *spi = priv->spi;
93
94 const u16 slpout = 0x11;
95 const u16 dison = 0x29;
96
97 const u16 slpin = 0x10;
98 const u16 disoff = 0x28;
99
100 if (power <= FB_BLANK_NORMAL) {
101 if (priv->lcd_state <= FB_BLANK_NORMAL) {
102 /* Do nothing, the LCD is running */
103 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
104 dev_dbg(&spi->dev, "Resuming LCD\n");
105
106 spi_write(spi, (const u8 *)&slpout, sizeof(u16));
107 msleep(60);
108 spi_write(spi, (const u8 *)&dison, sizeof(u16));
109 } else {
110 /* priv->lcd_state == FB_BLANK_POWERDOWN */
111 l4f00242t03_lcd_init(spi);
112 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
113 l4f00242t03_lcd_power_set(priv->ld, power);
114 }
115 } else if (power < FB_BLANK_POWERDOWN) {
116 if (priv->lcd_state <= FB_BLANK_NORMAL) {
117 /* Send the display in standby */
118 dev_dbg(&spi->dev, "Standby the LCD\n");
119
120 spi_write(spi, (const u8 *)&disoff, sizeof(u16));
121 msleep(60);
122 spi_write(spi, (const u8 *)&slpin, sizeof(u16));
123 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
124 /* Do nothing, the LCD is already in standby */
125 } else {
126 /* priv->lcd_state == FB_BLANK_POWERDOWN */
127 l4f00242t03_lcd_init(spi);
128 priv->lcd_state = FB_BLANK_UNBLANK;
129 l4f00242t03_lcd_power_set(ld, power);
130 }
131 } else {
132 /* power == FB_BLANK_POWERDOWN */
133 if (priv->lcd_state != FB_BLANK_POWERDOWN) {
134 /* Clear the screen before shutting down */
135 spi_write(spi, (const u8 *)&disoff, sizeof(u16));
136 msleep(60);
137 l4f00242t03_lcd_powerdown(spi);
138 }
139 }
140
141 priv->lcd_state = power;
142
143 return 0;
144 }
145
146 static struct lcd_ops l4f_ops = {
147 .set_power = l4f00242t03_lcd_power_set,
148 .get_power = l4f00242t03_lcd_power_get,
149 };
150
l4f00242t03_probe(struct spi_device * spi)151 static int __devinit l4f00242t03_probe(struct spi_device *spi)
152 {
153 struct l4f00242t03_priv *priv;
154 struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
155 int ret;
156
157 if (pdata == NULL) {
158 dev_err(&spi->dev, "Uninitialized platform data.\n");
159 return -EINVAL;
160 }
161
162 priv = kzalloc(sizeof(struct l4f00242t03_priv), GFP_KERNEL);
163
164 if (priv == NULL) {
165 dev_err(&spi->dev, "No memory for this device.\n");
166 return -ENOMEM;
167 }
168
169 dev_set_drvdata(&spi->dev, priv);
170 spi->bits_per_word = 9;
171 spi_setup(spi);
172
173 priv->spi = spi;
174
175 ret = gpio_request_one(pdata->reset_gpio, GPIOF_OUT_INIT_HIGH,
176 "lcd l4f00242t03 reset");
177 if (ret) {
178 dev_err(&spi->dev,
179 "Unable to get the lcd l4f00242t03 reset gpio.\n");
180 goto err;
181 }
182
183 ret = gpio_request_one(pdata->data_enable_gpio, GPIOF_OUT_INIT_LOW,
184 "lcd l4f00242t03 data enable");
185 if (ret) {
186 dev_err(&spi->dev,
187 "Unable to get the lcd l4f00242t03 data en gpio.\n");
188 goto err2;
189 }
190
191 priv->io_reg = regulator_get(&spi->dev, "vdd");
192 if (IS_ERR(priv->io_reg)) {
193 ret = PTR_ERR(priv->io_reg);
194 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n",
195 __func__);
196 goto err3;
197 }
198
199 priv->core_reg = regulator_get(&spi->dev, "vcore");
200 if (IS_ERR(priv->core_reg)) {
201 ret = PTR_ERR(priv->core_reg);
202 dev_err(&spi->dev, "%s: Unable to get the core regulator\n",
203 __func__);
204 goto err4;
205 }
206
207 priv->ld = lcd_device_register("l4f00242t03",
208 &spi->dev, priv, &l4f_ops);
209 if (IS_ERR(priv->ld)) {
210 ret = PTR_ERR(priv->ld);
211 goto err5;
212 }
213
214 /* Init the LCD */
215 l4f00242t03_lcd_init(spi);
216 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
217 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK);
218
219 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");
220
221 return 0;
222
223 err5:
224 regulator_put(priv->core_reg);
225 err4:
226 regulator_put(priv->io_reg);
227 err3:
228 gpio_free(pdata->data_enable_gpio);
229 err2:
230 gpio_free(pdata->reset_gpio);
231 err:
232 kfree(priv);
233
234 return ret;
235 }
236
l4f00242t03_remove(struct spi_device * spi)237 static int __devexit l4f00242t03_remove(struct spi_device *spi)
238 {
239 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
240 struct l4f00242t03_pdata *pdata = priv->spi->dev.platform_data;
241
242 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
243 lcd_device_unregister(priv->ld);
244
245 dev_set_drvdata(&spi->dev, NULL);
246
247 gpio_free(pdata->data_enable_gpio);
248 gpio_free(pdata->reset_gpio);
249
250 regulator_put(priv->io_reg);
251 regulator_put(priv->core_reg);
252
253 kfree(priv);
254
255 return 0;
256 }
257
l4f00242t03_shutdown(struct spi_device * spi)258 static void l4f00242t03_shutdown(struct spi_device *spi)
259 {
260 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
261
262 if (priv)
263 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
264
265 }
266
267 static struct spi_driver l4f00242t03_driver = {
268 .driver = {
269 .name = "l4f00242t03",
270 .owner = THIS_MODULE,
271 },
272 .probe = l4f00242t03_probe,
273 .remove = __devexit_p(l4f00242t03_remove),
274 .shutdown = l4f00242t03_shutdown,
275 };
276
l4f00242t03_init(void)277 static __init int l4f00242t03_init(void)
278 {
279 return spi_register_driver(&l4f00242t03_driver);
280 }
281
l4f00242t03_exit(void)282 static __exit void l4f00242t03_exit(void)
283 {
284 spi_unregister_driver(&l4f00242t03_driver);
285 }
286
287 module_init(l4f00242t03_init);
288 module_exit(l4f00242t03_exit);
289
290 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
291 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");
292 MODULE_LICENSE("GPL v2");
293