Staging: vt6656: code cleanup, fixed comments style at the end of headers
[linux-2.6.git] / drivers / video / backlight / ili9320.c
blob5118a9f029aba5a872c231239d9f86c52738b73c
1 /* drivers/video/backlight/ili9320.c
3 * ILI9320 LCD controller driver core.
5 * Copyright 2007 Simtec Electronics
6 * http://armlinux.simtec.co.uk/
7 * Ben Dooks <ben@simtec.co.uk>
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.
14 #include <linux/delay.h>
15 #include <linux/err.h>
16 #include <linux/fb.h>
17 #include <linux/init.h>
18 #include <linux/lcd.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
22 #include <linux/spi/spi.h>
24 #include <video/ili9320.h>
26 #include "ili9320.h"
29 static inline int ili9320_write_spi(struct ili9320 *ili,
30 unsigned int reg,
31 unsigned int value)
33 struct ili9320_spi *spi = &ili->access.spi;
34 unsigned char *addr = spi->buffer_addr;
35 unsigned char *data = spi->buffer_data;
37 /* spi message consits of:
38 * first byte: ID and operation
41 addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
42 addr[1] = reg >> 8;
43 addr[2] = reg;
45 /* second message is the data to transfer */
47 data[0] = spi->id | ILI9320_SPI_DATA | ILI9320_SPI_WRITE;
48 data[1] = value >> 8;
49 data[2] = value;
51 return spi_sync(spi->dev, &spi->message);
54 int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
56 dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
57 return ili->write(ili, reg, value);
60 EXPORT_SYMBOL_GPL(ili9320_write);
62 int ili9320_write_regs(struct ili9320 *ili,
63 struct ili9320_reg *values,
64 int nr_values)
66 int index;
67 int ret;
69 for (index = 0; index < nr_values; index++, values++) {
70 ret = ili9320_write(ili, values->address, values->value);
71 if (ret != 0)
72 return ret;
75 return 0;
78 EXPORT_SYMBOL_GPL(ili9320_write_regs);
80 static void ili9320_reset(struct ili9320 *lcd)
82 struct ili9320_platdata *cfg = lcd->platdata;
84 cfg->reset(1);
85 mdelay(50);
87 cfg->reset(0);
88 mdelay(50);
90 cfg->reset(1);
91 mdelay(100);
94 static inline int ili9320_init_chip(struct ili9320 *lcd)
96 int ret;
98 ili9320_reset(lcd);
100 ret = lcd->client->init(lcd, lcd->platdata);
101 if (ret != 0) {
102 dev_err(lcd->dev, "failed to initialise display\n");
103 return ret;
106 lcd->initialised = 1;
107 return 0;
110 static inline int ili9320_power_on(struct ili9320 *lcd)
112 if (!lcd->initialised)
113 ili9320_init_chip(lcd);
115 lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
116 ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
118 return 0;
121 static inline int ili9320_power_off(struct ili9320 *lcd)
123 lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
124 ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
126 return 0;
129 #define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL)
131 static int ili9320_power(struct ili9320 *lcd, int power)
133 int ret = 0;
135 dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
137 if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
138 ret = ili9320_power_on(lcd);
139 else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
140 ret = ili9320_power_off(lcd);
142 if (ret == 0)
143 lcd->power = power;
144 else
145 dev_warn(lcd->dev, "failed to set power mode %d\n", power);
147 return ret;
150 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
152 return lcd_get_data(lcd);
155 static int ili9320_set_power(struct lcd_device *ld, int power)
157 struct ili9320 *lcd = to_our_lcd(ld);
159 return ili9320_power(lcd, power);
162 static int ili9320_get_power(struct lcd_device *ld)
164 struct ili9320 *lcd = to_our_lcd(ld);
166 return lcd->power;
169 static struct lcd_ops ili9320_ops = {
170 .get_power = ili9320_get_power,
171 .set_power = ili9320_set_power,
174 static void __devinit ili9320_setup_spi(struct ili9320 *ili,
175 struct spi_device *dev)
177 struct ili9320_spi *spi = &ili->access.spi;
179 ili->write = ili9320_write_spi;
180 spi->dev = dev;
182 /* fill the two messages we are going to use to send the data
183 * with, the first the address followed by the data. The datasheet
184 * says they should be done as two distinct cycles of the SPI CS line.
187 spi->xfer[0].tx_buf = spi->buffer_addr;
188 spi->xfer[1].tx_buf = spi->buffer_data;
189 spi->xfer[0].len = 3;
190 spi->xfer[1].len = 3;
191 spi->xfer[0].bits_per_word = 8;
192 spi->xfer[1].bits_per_word = 8;
193 spi->xfer[0].cs_change = 1;
195 spi_message_init(&spi->message);
196 spi_message_add_tail(&spi->xfer[0], &spi->message);
197 spi_message_add_tail(&spi->xfer[1], &spi->message);
200 int __devinit ili9320_probe_spi(struct spi_device *spi,
201 struct ili9320_client *client)
203 struct ili9320_platdata *cfg = spi->dev.platform_data;
204 struct device *dev = &spi->dev;
205 struct ili9320 *ili;
206 struct lcd_device *lcd;
207 int ret = 0;
209 /* verify we where given some information */
211 if (cfg == NULL) {
212 dev_err(dev, "no platform data supplied\n");
213 return -EINVAL;
216 if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
217 dev_err(dev, "invalid platform data supplied\n");
218 return -EINVAL;
221 /* allocate and initialse our state */
223 ili = kzalloc(sizeof(struct ili9320), GFP_KERNEL);
224 if (ili == NULL) {
225 dev_err(dev, "no memory for device\n");
226 return -ENOMEM;
229 ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
231 ili->dev = dev;
232 ili->client = client;
233 ili->power = FB_BLANK_POWERDOWN;
234 ili->platdata = cfg;
236 dev_set_drvdata(&spi->dev, ili);
238 ili9320_setup_spi(ili, spi);
240 lcd = lcd_device_register("ili9320", dev, ili, &ili9320_ops);
241 if (IS_ERR(lcd)) {
242 dev_err(dev, "failed to register lcd device\n");
243 ret = PTR_ERR(lcd);
244 goto err_free;
247 ili->lcd = lcd;
249 dev_info(dev, "initialising %s\n", client->name);
251 ret = ili9320_power(ili, FB_BLANK_UNBLANK);
252 if (ret != 0) {
253 dev_err(dev, "failed to set lcd power state\n");
254 goto err_unregister;
257 return 0;
259 err_unregister:
260 lcd_device_unregister(lcd);
262 err_free:
263 kfree(ili);
265 return ret;
268 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
270 int __devexit ili9320_remove(struct ili9320 *ili)
272 ili9320_power(ili, FB_BLANK_POWERDOWN);
274 lcd_device_unregister(ili->lcd);
275 kfree(ili);
277 return 0;
280 EXPORT_SYMBOL_GPL(ili9320_remove);
282 #ifdef CONFIG_PM
283 int ili9320_suspend(struct ili9320 *lcd, pm_message_t state)
285 int ret;
287 dev_dbg(lcd->dev, "%s: event %d\n", __func__, state.event);
289 if (state.event == PM_EVENT_SUSPEND) {
290 ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
292 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
293 ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
294 ILI9320_POWER1_SLP |
295 ILI9320_POWER1_DSTB);
296 lcd->initialised = 0;
299 return ret;
302 return 0;
305 EXPORT_SYMBOL_GPL(ili9320_suspend);
307 int ili9320_resume(struct ili9320 *lcd)
309 dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
311 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
312 ili9320_write(lcd, ILI9320_POWER1, 0x00);
315 return ili9320_power(lcd, FB_BLANK_UNBLANK);
318 EXPORT_SYMBOL_GPL(ili9320_resume);
319 #endif
321 /* Power down all displays on reboot, poweroff or halt */
322 void ili9320_shutdown(struct ili9320 *lcd)
324 ili9320_power(lcd, FB_BLANK_POWERDOWN);
327 EXPORT_SYMBOL_GPL(ili9320_shutdown);
329 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
330 MODULE_DESCRIPTION("ILI9320 LCD Driver");
331 MODULE_LICENSE("GPL v2");