1 /* drivers/video/backlight/ili9320.c
2  *
3  * ILI9320 LCD controller driver core.
4  *
5  * Copyright 2007 Simtec Electronics
6  *	http://armlinux.simtec.co.uk/
7  *	Ben Dooks <ben@simtec.co.uk>
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/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>
21 
22 #include <linux/spi/spi.h>
23 
24 #include <video/ili9320.h>
25 
26 #include "ili9320.h"
27 
28 
29 static inline int ili9320_write_spi(struct ili9320 *ili,
30 				    unsigned int reg,
31 				    unsigned int value)
32 {
33 	struct ili9320_spi *spi = &ili->access.spi;
34 	unsigned char *addr = spi->buffer_addr;
35 	unsigned char *data = spi->buffer_data;
36 
37 	/* spi message consits of:
38 	 * first byte: ID and operation
39 	 */
40 
41 	addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
42 	addr[1] = reg >> 8;
43 	addr[2] = reg;
44 
45 	/* second message is the data to transfer */
46 
47 	data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
48 	data[1] = value >> 8;
49 	data[2] = value;
50 
51 	return spi_sync(spi->dev, &spi->message);
52 }
53 
54 int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
55 {
56 	dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
57 	return ili->write(ili, reg, value);
58 }
59 EXPORT_SYMBOL_GPL(ili9320_write);
60 
61 int ili9320_write_regs(struct ili9320 *ili,
62 		       const struct ili9320_reg *values,
63 		       int nr_values)
64 {
65 	int index;
66 	int ret;
67 
68 	for (index = 0; index < nr_values; index++, values++) {
69 		ret = ili9320_write(ili, values->address, values->value);
70 		if (ret != 0)
71 			return ret;
72 	}
73 
74 	return 0;
75 }
76 EXPORT_SYMBOL_GPL(ili9320_write_regs);
77 
78 static void ili9320_reset(struct ili9320 *lcd)
79 {
80 	struct ili9320_platdata *cfg = lcd->platdata;
81 
82 	cfg->reset(1);
83 	mdelay(50);
84 
85 	cfg->reset(0);
86 	mdelay(50);
87 
88 	cfg->reset(1);
89 	mdelay(100);
90 }
91 
92 static inline int ili9320_init_chip(struct ili9320 *lcd)
93 {
94 	int ret;
95 
96 	ili9320_reset(lcd);
97 
98 	ret = lcd->client->init(lcd, lcd->platdata);
99 	if (ret != 0) {
100 		dev_err(lcd->dev, "failed to initialise display\n");
101 		return ret;
102 	}
103 
104 	lcd->initialised = 1;
105 	return 0;
106 }
107 
108 static inline int ili9320_power_on(struct ili9320 *lcd)
109 {
110 	if (!lcd->initialised)
111 		ili9320_init_chip(lcd);
112 
113 	lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
114 	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
115 
116 	return 0;
117 }
118 
119 static inline int ili9320_power_off(struct ili9320 *lcd)
120 {
121 	lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
122 	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
123 
124 	return 0;
125 }
126 
127 #define POWER_IS_ON(pwr)	((pwr) <= FB_BLANK_NORMAL)
128 
129 static int ili9320_power(struct ili9320 *lcd, int power)
130 {
131 	int ret = 0;
132 
133 	dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
134 
135 	if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
136 		ret = ili9320_power_on(lcd);
137 	else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
138 		ret = ili9320_power_off(lcd);
139 
140 	if (ret == 0)
141 		lcd->power = power;
142 	else
143 		dev_warn(lcd->dev, "failed to set power mode %d\n", power);
144 
145 	return ret;
146 }
147 
148 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
149 {
150 	return lcd_get_data(lcd);
151 }
152 
153 static int ili9320_set_power(struct lcd_device *ld, int power)
154 {
155 	struct ili9320 *lcd = to_our_lcd(ld);
156 
157 	return ili9320_power(lcd, power);
158 }
159 
160 static int ili9320_get_power(struct lcd_device *ld)
161 {
162 	struct ili9320 *lcd = to_our_lcd(ld);
163 
164 	return lcd->power;
165 }
166 
167 static struct lcd_ops ili9320_ops = {
168 	.get_power	= ili9320_get_power,
169 	.set_power	= ili9320_set_power,
170 };
171 
172 static void ili9320_setup_spi(struct ili9320 *ili,
173 					struct spi_device *dev)
174 {
175 	struct ili9320_spi *spi = &ili->access.spi;
176 
177 	ili->write = ili9320_write_spi;
178 	spi->dev = dev;
179 
180 	/* fill the two messages we are going to use to send the data
181 	 * with, the first the address followed by the data. The datasheet
182 	 * says they should be done as two distinct cycles of the SPI CS line.
183 	 */
184 
185 	spi->xfer[0].tx_buf = spi->buffer_addr;
186 	spi->xfer[1].tx_buf = spi->buffer_data;
187 	spi->xfer[0].len = 3;
188 	spi->xfer[1].len = 3;
189 	spi->xfer[0].bits_per_word = 8;
190 	spi->xfer[1].bits_per_word = 8;
191 	spi->xfer[0].cs_change = 1;
192 
193 	spi_message_init(&spi->message);
194 	spi_message_add_tail(&spi->xfer[0], &spi->message);
195 	spi_message_add_tail(&spi->xfer[1], &spi->message);
196 }
197 
198 int ili9320_probe_spi(struct spi_device *spi,
199 				struct ili9320_client *client)
200 {
201 	struct ili9320_platdata *cfg = dev_get_platdata(&spi->dev);
202 	struct device *dev = &spi->dev;
203 	struct ili9320 *ili;
204 	struct lcd_device *lcd;
205 	int ret = 0;
206 
207 	/* verify we where given some information */
208 
209 	if (cfg == NULL) {
210 		dev_err(dev, "no platform data supplied\n");
211 		return -EINVAL;
212 	}
213 
214 	if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
215 		dev_err(dev, "invalid platform data supplied\n");
216 		return -EINVAL;
217 	}
218 
219 	/* allocate and initialse our state */
220 
221 	ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
222 	if (ili == NULL) {
223 		dev_err(dev, "no memory for device\n");
224 		return -ENOMEM;
225 	}
226 
227 	ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
228 
229 	ili->dev = dev;
230 	ili->client = client;
231 	ili->power = FB_BLANK_POWERDOWN;
232 	ili->platdata = cfg;
233 
234 	spi_set_drvdata(spi, ili);
235 
236 	ili9320_setup_spi(ili, spi);
237 
238 	lcd = devm_lcd_device_register(&spi->dev, "ili9320", dev, ili,
239 					&ili9320_ops);
240 	if (IS_ERR(lcd)) {
241 		dev_err(dev, "failed to register lcd device\n");
242 		return PTR_ERR(lcd);
243 	}
244 
245 	ili->lcd = lcd;
246 
247 	dev_info(dev, "initialising %s\n", client->name);
248 
249 	ret = ili9320_power(ili, FB_BLANK_UNBLANK);
250 	if (ret != 0) {
251 		dev_err(dev, "failed to set lcd power state\n");
252 		return ret;
253 	}
254 
255 	return 0;
256 }
257 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
258 
259 int ili9320_remove(struct ili9320 *ili)
260 {
261 	ili9320_power(ili, FB_BLANK_POWERDOWN);
262 	return 0;
263 }
264 EXPORT_SYMBOL_GPL(ili9320_remove);
265 
266 #ifdef CONFIG_PM_SLEEP
267 int ili9320_suspend(struct ili9320 *lcd)
268 {
269 	int ret;
270 
271 	ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
272 
273 	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
274 		ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
275 			      ILI9320_POWER1_SLP |
276 			      ILI9320_POWER1_DSTB);
277 		lcd->initialised = 0;
278 	}
279 
280 	return ret;
281 }
282 EXPORT_SYMBOL_GPL(ili9320_suspend);
283 
284 int ili9320_resume(struct ili9320 *lcd)
285 {
286 	dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
287 
288 	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
289 		ili9320_write(lcd, ILI9320_POWER1, 0x00);
290 
291 	return ili9320_power(lcd, FB_BLANK_UNBLANK);
292 }
293 EXPORT_SYMBOL_GPL(ili9320_resume);
294 #endif
295 
296 /* Power down all displays on reboot, poweroff or halt */
297 void ili9320_shutdown(struct ili9320 *lcd)
298 {
299 	ili9320_power(lcd, FB_BLANK_POWERDOWN);
300 }
301 EXPORT_SYMBOL_GPL(ili9320_shutdown);
302 
303 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
304 MODULE_DESCRIPTION("ILI9320 LCD Driver");
305 MODULE_LICENSE("GPL v2");
306