1// SPDX-License-Identifier: GPL-2.0-only
2/* drivers/video/backlight/ili9320.c
3 *
4 * ILI9320 LCD controller driver core.
5 *
6 * Copyright 2007 Simtec Electronics
7 *	http://armlinux.simtec.co.uk/
8 *	Ben Dooks <ben@simtec.co.uk>
9*/
10
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/fb.h>
14#include <linux/init.h>
15#include <linux/lcd.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18
19#include <linux/spi/spi.h>
20
21#include <video/ili9320.h>
22
23#include "ili9320.h"
24
25
26static inline int ili9320_write_spi(struct ili9320 *ili,
27				    unsigned int reg,
28				    unsigned int value)
29{
30	struct ili9320_spi *spi = &ili->access.spi;
31	unsigned char *addr = spi->buffer_addr;
32	unsigned char *data = spi->buffer_data;
33
34	/* spi message consits of:
35	 * first byte: ID and operation
36	 */
37
38	addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
39	addr[1] = reg >> 8;
40	addr[2] = reg;
41
42	/* second message is the data to transfer */
43
44	data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
45	data[1] = value >> 8;
46	data[2] = value;
47
48	return spi_sync(spi->dev, &spi->message);
49}
50
51int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
52{
53	dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
54	return ili->write(ili, reg, value);
55}
56EXPORT_SYMBOL_GPL(ili9320_write);
57
58int ili9320_write_regs(struct ili9320 *ili,
59		       const struct ili9320_reg *values,
60		       int nr_values)
61{
62	int index;
63	int ret;
64
65	for (index = 0; index < nr_values; index++, values++) {
66		ret = ili9320_write(ili, values->address, values->value);
67		if (ret != 0)
68			return ret;
69	}
70
71	return 0;
72}
73EXPORT_SYMBOL_GPL(ili9320_write_regs);
74
75static void ili9320_reset(struct ili9320 *lcd)
76{
77	struct ili9320_platdata *cfg = lcd->platdata;
78
79	cfg->reset(1);
80	mdelay(50);
81
82	cfg->reset(0);
83	mdelay(50);
84
85	cfg->reset(1);
86	mdelay(100);
87}
88
89static inline int ili9320_init_chip(struct ili9320 *lcd)
90{
91	int ret;
92
93	ili9320_reset(lcd);
94
95	ret = lcd->client->init(lcd, lcd->platdata);
96	if (ret != 0) {
97		dev_err(lcd->dev, "failed to initialise display\n");
98		return ret;
99	}
100
101	lcd->initialised = 1;
102	return 0;
103}
104
105static inline int ili9320_power_on(struct ili9320 *lcd)
106{
107	if (!lcd->initialised)
108		ili9320_init_chip(lcd);
109
110	lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
111	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
112
113	return 0;
114}
115
116static inline int ili9320_power_off(struct ili9320 *lcd)
117{
118	lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
119	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
120
121	return 0;
122}
123
124#define POWER_IS_ON(pwr)	((pwr) <= FB_BLANK_NORMAL)
125
126static int ili9320_power(struct ili9320 *lcd, int power)
127{
128	int ret = 0;
129
130	dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
131
132	if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
133		ret = ili9320_power_on(lcd);
134	else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
135		ret = ili9320_power_off(lcd);
136
137	if (ret == 0)
138		lcd->power = power;
139	else
140		dev_warn(lcd->dev, "failed to set power mode %d\n", power);
141
142	return ret;
143}
144
145static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
146{
147	return lcd_get_data(lcd);
148}
149
150static int ili9320_set_power(struct lcd_device *ld, int power)
151{
152	struct ili9320 *lcd = to_our_lcd(ld);
153
154	return ili9320_power(lcd, power);
155}
156
157static int ili9320_get_power(struct lcd_device *ld)
158{
159	struct ili9320 *lcd = to_our_lcd(ld);
160
161	return lcd->power;
162}
163
164static struct lcd_ops ili9320_ops = {
165	.get_power	= ili9320_get_power,
166	.set_power	= ili9320_set_power,
167};
168
169static void ili9320_setup_spi(struct ili9320 *ili,
170					struct spi_device *dev)
171{
172	struct ili9320_spi *spi = &ili->access.spi;
173
174	ili->write = ili9320_write_spi;
175	spi->dev = dev;
176
177	/* fill the two messages we are going to use to send the data
178	 * with, the first the address followed by the data. The datasheet
179	 * says they should be done as two distinct cycles of the SPI CS line.
180	 */
181
182	spi->xfer[0].tx_buf = spi->buffer_addr;
183	spi->xfer[1].tx_buf = spi->buffer_data;
184	spi->xfer[0].len = 3;
185	spi->xfer[1].len = 3;
186	spi->xfer[0].bits_per_word = 8;
187	spi->xfer[1].bits_per_word = 8;
188	spi->xfer[0].cs_change = 1;
189
190	spi_message_init(&spi->message);
191	spi_message_add_tail(&spi->xfer[0], &spi->message);
192	spi_message_add_tail(&spi->xfer[1], &spi->message);
193}
194
195int ili9320_probe_spi(struct spi_device *spi,
196				struct ili9320_client *client)
197{
198	struct ili9320_platdata *cfg = dev_get_platdata(&spi->dev);
199	struct device *dev = &spi->dev;
200	struct ili9320 *ili;
201	struct lcd_device *lcd;
202	int ret = 0;
203
204	/* verify we where given some information */
205
206	if (cfg == NULL) {
207		dev_err(dev, "no platform data supplied\n");
208		return -EINVAL;
209	}
210
211	if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
212		dev_err(dev, "invalid platform data supplied\n");
213		return -EINVAL;
214	}
215
216	/* allocate and initialse our state */
217
218	ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
219	if (ili == NULL)
220		return -ENOMEM;
221
222	ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
223
224	ili->dev = dev;
225	ili->client = client;
226	ili->power = FB_BLANK_POWERDOWN;
227	ili->platdata = cfg;
228
229	spi_set_drvdata(spi, ili);
230
231	ili9320_setup_spi(ili, spi);
232
233	lcd = devm_lcd_device_register(&spi->dev, "ili9320", dev, ili,
234					&ili9320_ops);
235	if (IS_ERR(lcd)) {
236		dev_err(dev, "failed to register lcd device\n");
237		return PTR_ERR(lcd);
238	}
239
240	ili->lcd = lcd;
241
242	dev_info(dev, "initialising %s\n", client->name);
243
244	ret = ili9320_power(ili, FB_BLANK_UNBLANK);
245	if (ret != 0) {
246		dev_err(dev, "failed to set lcd power state\n");
247		return ret;
248	}
249
250	return 0;
251}
252EXPORT_SYMBOL_GPL(ili9320_probe_spi);
253
254void ili9320_remove(struct ili9320 *ili)
255{
256	ili9320_power(ili, FB_BLANK_POWERDOWN);
257}
258EXPORT_SYMBOL_GPL(ili9320_remove);
259
260#ifdef CONFIG_PM_SLEEP
261int ili9320_suspend(struct ili9320 *lcd)
262{
263	int ret;
264
265	ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
266
267	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
268		ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
269			      ILI9320_POWER1_SLP |
270			      ILI9320_POWER1_DSTB);
271		lcd->initialised = 0;
272	}
273
274	return ret;
275}
276EXPORT_SYMBOL_GPL(ili9320_suspend);
277
278int ili9320_resume(struct ili9320 *lcd)
279{
280	dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
281
282	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
283		ili9320_write(lcd, ILI9320_POWER1, 0x00);
284
285	return ili9320_power(lcd, FB_BLANK_UNBLANK);
286}
287EXPORT_SYMBOL_GPL(ili9320_resume);
288#endif
289
290/* Power down all displays on reboot, poweroff or halt */
291void ili9320_shutdown(struct ili9320 *lcd)
292{
293	ili9320_power(lcd, FB_BLANK_POWERDOWN);
294}
295EXPORT_SYMBOL_GPL(ili9320_shutdown);
296
297MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
298MODULE_DESCRIPTION("ILI9320 LCD Driver");
299MODULE_LICENSE("GPL v2");
300