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: spi->dev, message: &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(ld_dev: lcd);
148}
149
150static int ili9320_set_power(struct lcd_device *ld, int power)
151{
152 struct ili9320 *lcd = to_our_lcd(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(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(m: &spi->message);
191 spi_message_add_tail(t: &spi->xfer[0], m: &spi->message);
192 spi_message_add_tail(t: &spi->xfer[1], m: &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(dev: &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(dev: &spi->dev, size: 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, data: ili);
230
231 ili9320_setup_spi(ili, dev: spi);
232
233 lcd = devm_lcd_device_register(dev: &spi->dev, name: "ili9320", parent: dev, devdata: ili,
234 ops: &ili9320_ops);
235 if (IS_ERR(ptr: lcd)) {
236 dev_err(dev, "failed to register lcd device\n");
237 return PTR_ERR(ptr: lcd);
238 }
239
240 ili->lcd = lcd;
241
242 dev_info(dev, "initialising %s\n", client->name);
243
244 ret = ili9320_power(lcd: ili, power: 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(lcd: ili, power: 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, power: 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, power: 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, power: 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

source code of linux/drivers/video/backlight/ili9320.c