aboutsummaryrefslogtreecommitdiff
path: root/drivers/video/backlight/ili9320.c
blob: f8be90c5dedcbd772f8d0ad3a6c685da8eb6b9b4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
/* drivers/video/backlight/ili9320.c
 *
 * ILI9320 LCD controller driver core.
 *
 * Copyright 2007 Simtec Electronics
 *	http://armlinux.simtec.co.uk/
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
*/

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/lcd.h>
#include <linux/module.h>
#include <linux/slab.h>

#include <linux/spi/spi.h>

#include <video/ili9320.h>

#include "ili9320.h"


static inline int ili9320_write_spi(struct ili9320 *ili,
				    unsigned int reg,
				    unsigned int value)
{
	struct ili9320_spi *spi = &ili->access.spi;
	unsigned char *addr = spi->buffer_addr;
	unsigned char *data = spi->buffer_data;

	/* spi message consits of:
	 * first byte: ID and operation
	 */

	addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
	addr[1] = reg >> 8;
	addr[2] = reg;

	/* second message is the data to transfer */

	data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
	data[1] = value >> 8;
	data[2] = value;

	return spi_sync(spi->dev, &spi->message);
}

int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
{
	dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
	return ili->write(ili, reg, value);
}
EXPORT_SYMBOL_GPL(ili9320_write);

int ili9320_write_regs(struct ili9320 *ili,
		       const struct ili9320_reg *values,
		       int nr_values)
{
	int index;
	int ret;

	for (index = 0; index < nr_values; index++, values++) {
		ret = ili9320_write(ili, values->address, values->value);
		if (ret != 0)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(ili9320_write_regs);

static void ili9320_reset(struct ili9320 *lcd)
{
	struct ili9320_platdata *cfg = lcd->platdata;

	cfg->reset(1);
	mdelay(50);

	cfg->reset(0);
	mdelay(50);

	cfg->reset(1);
	mdelay(100);
}

static inline int ili9320_init_chip(struct ili9320 *lcd)
{
	int ret;

	ili9320_reset(lcd);

	ret = lcd->client->init(lcd, lcd->platdata);
	if (ret != 0) {
		dev_err(lcd->dev, "failed to initialise display\n");
		return ret;
	}

	lcd->initialised = 1;
	return 0;
}

static inline int ili9320_power_on(struct ili9320 *lcd)
{
	if (!lcd->initialised)
		ili9320_init_chip(lcd);

	lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);

	return 0;
}

static inline int ili9320_power_off(struct ili9320 *lcd)
{
	lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);

	return 0;
}

#define POWER_IS_ON(pwr)	((pwr) <= FB_BLANK_NORMAL)

static int ili9320_power(struct ili9320 *lcd, int power)
{
	int ret = 0;

	dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);

	if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
		ret = ili9320_power_on(lcd);
	else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
		ret = ili9320_power_off(lcd);

	if (ret == 0)
		lcd->power = power;
	else
		dev_warn(lcd->dev, "failed to set power mode %d\n", power);

	return ret;
}

static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
{
	return lcd_get_data(lcd);
}

static int ili9320_set_power(struct lcd_device *ld, int power)
{
	struct ili9320 *lcd = to_our_lcd(ld);

	return ili9320_power(lcd, power);
}

static int ili9320_get_power(struct lcd_device *ld)
{
	struct ili9320 *lcd = to_our_lcd(ld);

	return lcd->power;
}

static struct lcd_ops ili9320_ops = {
	.get_power	= ili9320_get_power,
	.set_power	= ili9320_set_power,
};

static void ili9320_setup_spi(struct ili9320 *ili,
					struct spi_device *dev)
{
	struct ili9320_spi *spi = &ili->access.spi;

	ili->write = ili9320_write_spi;
	spi->dev = dev;

	/* fill the two messages we are going to use to send the data
	 * with, the first the address followed by the data. The datasheet
	 * says they should be done as two distinct cycles of the SPI CS line.
	 */

	spi->xfer[0].tx_buf = spi->buffer_addr;
	spi->xfer[1].tx_buf = spi->buffer_data;
	spi->xfer[0].len = 3;
	spi->xfer[1].len = 3;
	spi->xfer[0].bits_per_word = 8;
	spi->xfer[1].bits_per_word = 8;
	spi->xfer[0].cs_change = 1;

	spi_message_init(&spi->message);
	spi_message_add_tail(&spi->xfer[0], &spi->message);
	spi_message_add_tail(&spi->xfer[1], &spi->message);
}

int ili9320_probe_spi(struct spi_device *spi,
				struct ili9320_client *client)
{
	struct ili9320_platdata *cfg = spi->dev.platform_data;
	struct device *dev = &spi->dev;
	struct ili9320 *ili;
	struct lcd_device *lcd;
	int ret = 0;

	/* verify we where given some information */

	if (cfg == NULL) {
		dev_err(dev, "no platform data supplied\n");
		return -EINVAL;
	}

	if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
		dev_err(dev, "invalid platform data supplied\n");
		return -EINVAL;
	}

	/* allocate and initialse our state */

	ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
	if (ili == NULL) {
		dev_err(dev, "no memory for device\n");
		return -ENOMEM;
	}

	ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);

	ili->dev = dev;
	ili->client = client;
	ili->power = FB_BLANK_POWERDOWN;
	ili->platdata = cfg;

	spi_set_drvdata(spi, ili);

	ili9320_setup_spi(ili, spi);

	lcd = lcd_device_register("ili9320", dev, ili, &ili9320_ops);
	if (IS_ERR(lcd)) {
		dev_err(dev, "failed to register lcd device\n");
		return PTR_ERR(lcd);
	}

	ili->lcd = lcd;

	dev_info(dev, "initialising %s\n", client->name);

	ret = ili9320_power(ili, FB_BLANK_UNBLANK);
	if (ret != 0) {
		dev_err(dev, "failed to set lcd power state\n");
		goto err_unregister;
	}

	return 0;

 err_unregister:
	lcd_device_unregister(lcd);

	return ret;
}
EXPORT_SYMBOL_GPL(ili9320_probe_spi);

int ili9320_remove(struct ili9320 *ili)
{
	ili9320_power(ili, FB_BLANK_POWERDOWN);

	lcd_device_unregister(ili->lcd);

	return 0;
}
EXPORT_SYMBOL_GPL(ili9320_remove);

#ifdef CONFIG_PM_SLEEP
int ili9320_suspend(struct ili9320 *lcd)
{
	int ret;

	ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);

	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
		ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
			      ILI9320_POWER1_SLP |
			      ILI9320_POWER1_DSTB);
		lcd->initialised = 0;
	}

	return ret;
}
EXPORT_SYMBOL_GPL(ili9320_suspend);

int ili9320_resume(struct ili9320 *lcd)
{
	dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);

	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
		ili9320_write(lcd, ILI9320_POWER1, 0x00);

	return ili9320_power(lcd, FB_BLANK_UNBLANK);
}
EXPORT_SYMBOL_GPL(ili9320_resume);
#endif

/* Power down all displays on reboot, poweroff or halt */
void ili9320_shutdown(struct ili9320 *lcd)
{
	ili9320_power(lcd, FB_BLANK_POWERDOWN);
}
EXPORT_SYMBOL_GPL(ili9320_shutdown);

MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
MODULE_DESCRIPTION("ILI9320 LCD Driver");
MODULE_LICENSE("GPL v2");