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