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
29static 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
54int 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}
59EXPORT_SYMBOL_GPL(ili9320_write);
60
61int 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}
76EXPORT_SYMBOL_GPL(ili9320_write_regs);
77
78static 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
92static 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
108static 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
119static 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
129static 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
148static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
149{
150	return lcd_get_data(lcd);
151}
152
153static 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
160static int ili9320_get_power(struct lcd_device *ld)
161{
162	struct ili9320 *lcd = to_our_lcd(ld);
163
164	return lcd->power;
165}
166
167static struct lcd_ops ili9320_ops = {
168	.get_power	= ili9320_get_power,
169	.set_power	= ili9320_set_power,
170};
171
172static 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
198int 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		return -ENOMEM;
224
225	ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
226
227	ili->dev = dev;
228	ili->client = client;
229	ili->power = FB_BLANK_POWERDOWN;
230	ili->platdata = cfg;
231
232	spi_set_drvdata(spi, ili);
233
234	ili9320_setup_spi(ili, spi);
235
236	lcd = devm_lcd_device_register(&spi->dev, "ili9320", dev, ili,
237					&ili9320_ops);
238	if (IS_ERR(lcd)) {
239		dev_err(dev, "failed to register lcd device\n");
240		return PTR_ERR(lcd);
241	}
242
243	ili->lcd = lcd;
244
245	dev_info(dev, "initialising %s\n", client->name);
246
247	ret = ili9320_power(ili, FB_BLANK_UNBLANK);
248	if (ret != 0) {
249		dev_err(dev, "failed to set lcd power state\n");
250		return ret;
251	}
252
253	return 0;
254}
255EXPORT_SYMBOL_GPL(ili9320_probe_spi);
256
257int ili9320_remove(struct ili9320 *ili)
258{
259	ili9320_power(ili, FB_BLANK_POWERDOWN);
260	return 0;
261}
262EXPORT_SYMBOL_GPL(ili9320_remove);
263
264#ifdef CONFIG_PM_SLEEP
265int ili9320_suspend(struct ili9320 *lcd)
266{
267	int ret;
268
269	ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
270
271	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
272		ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
273			      ILI9320_POWER1_SLP |
274			      ILI9320_POWER1_DSTB);
275		lcd->initialised = 0;
276	}
277
278	return ret;
279}
280EXPORT_SYMBOL_GPL(ili9320_suspend);
281
282int ili9320_resume(struct ili9320 *lcd)
283{
284	dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
285
286	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
287		ili9320_write(lcd, ILI9320_POWER1, 0x00);
288
289	return ili9320_power(lcd, FB_BLANK_UNBLANK);
290}
291EXPORT_SYMBOL_GPL(ili9320_resume);
292#endif
293
294/* Power down all displays on reboot, poweroff or halt */
295void ili9320_shutdown(struct ili9320 *lcd)
296{
297	ili9320_power(lcd, FB_BLANK_POWERDOWN);
298}
299EXPORT_SYMBOL_GPL(ili9320_shutdown);
300
301MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
302MODULE_DESCRIPTION("ILI9320 LCD Driver");
303MODULE_LICENSE("GPL v2");
304