ili9320.c

  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
 25static 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
 50int 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}
 55EXPORT_SYMBOL_GPL(ili9320_write);
 56
 57int 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}
 72EXPORT_SYMBOL_GPL(ili9320_write_regs);
 73
 74static 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
 88static 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
104static 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
115static 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
125static 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
144static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
145{
146	return lcd_get_data(lcd);
147}
148
149static 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
156static int ili9320_get_power(struct lcd_device *ld)
157{
158	struct ili9320 *lcd = to_our_lcd(ld);
159
160	return lcd->power;
161}
162
163static const struct lcd_ops ili9320_ops = {
164	.get_power	= ili9320_get_power,
165	.set_power	= ili9320_set_power,
166};
167
168static 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
194int 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}
251EXPORT_SYMBOL_GPL(ili9320_probe_spi);
252
253void ili9320_remove(struct ili9320 *ili)
254{
255	ili9320_power(ili, LCD_POWER_OFF);
256}
257EXPORT_SYMBOL_GPL(ili9320_remove);
258
259#ifdef CONFIG_PM_SLEEP
260int 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}
275EXPORT_SYMBOL_GPL(ili9320_suspend);
276
277int 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}
286EXPORT_SYMBOL_GPL(ili9320_resume);
287#endif
288
289/* Power down all displays on reboot, poweroff or halt */
290void ili9320_shutdown(struct ili9320 *lcd)
291{
292	ili9320_power(lcd, LCD_POWER_OFF);
293}
294EXPORT_SYMBOL_GPL(ili9320_shutdown);
295
296MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
297MODULE_DESCRIPTION("ILI9320 LCD Driver");
298MODULE_LICENSE("GPL v2");