video/backlight/ili9320.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /* drivers/video/backlight/ili9320.c
0003  *
0004  * ILI9320 LCD controller driver core.
0005  *
0006  * Copyright 2007 Simtec Electronics
0007  *  http://armlinux.simtec.co.uk/
0008  *  Ben Dooks <ben@simtec.co.uk>
0009 */
0010
0011 #include <linux/delay.h>
0012 #include <linux/err.h>
0013 #include <linux/fb.h>
0014 #include <linux/init.h>
0015 #include <linux/lcd.h>
0016 #include <linux/module.h>
0017 #include <linux/slab.h>
0018
0019 #include <linux/spi/spi.h>
0020
0021 #include <video/ili9320.h>
0022
0023 #include "ili9320.h"
0024
0025
0026 static inline int ili9320_write_spi(struct ili9320 *ili,
0027                     unsigned int reg,
0028                     unsigned int value)
0029 {
0030     struct ili9320_spi *spi = &ili->access.spi;
0031     unsigned char *addr = spi->buffer_addr;
0032     unsigned char *data = spi->buffer_data;
0033
0034     /* spi message consits of:
0035      * first byte: ID and operation
0036      */
0037
0038     addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
0039     addr[1] = reg >> 8;
0040     addr[2] = reg;
0041
0042     /* second message is the data to transfer */
0043
0044     data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
0045     data[1] = value >> 8;
0046     data[2] = value;
0047
0048     return spi_sync(spi->dev, &spi->message);
0049 }
0050
0051 int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
0052 {
0053     dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
0054     return ili->write(ili, reg, value);
0055 }
0056 EXPORT_SYMBOL_GPL(ili9320_write);
0057
0058 int ili9320_write_regs(struct ili9320 *ili,
0059                const struct ili9320_reg *values,
0060                int nr_values)
0061 {
0062     int index;
0063     int ret;
0064
0065     for (index = 0; index < nr_values; index++, values++) {
0066         ret = ili9320_write(ili, values->address, values->value);
0067         if (ret != 0)
0068             return ret;
0069     }
0070
0071     return 0;
0072 }
0073 EXPORT_SYMBOL_GPL(ili9320_write_regs);
0074
0075 static void ili9320_reset(struct ili9320 *lcd)
0076 {
0077     struct ili9320_platdata *cfg = lcd->platdata;
0078
0079     cfg->reset(1);
0080     mdelay(50);
0081
0082     cfg->reset(0);
0083     mdelay(50);
0084
0085     cfg->reset(1);
0086     mdelay(100);
0087 }
0088
0089 static inline int ili9320_init_chip(struct ili9320 *lcd)
0090 {
0091     int ret;
0092
0093     ili9320_reset(lcd);
0094
0095     ret = lcd->client->init(lcd, lcd->platdata);
0096     if (ret != 0) {
0097         dev_err(lcd->dev, "failed to initialise display\n");
0098         return ret;
0099     }
0100
0101     lcd->initialised = 1;
0102     return 0;
0103 }
0104
0105 static inline int ili9320_power_on(struct ili9320 *lcd)
0106 {
0107     if (!lcd->initialised)
0108         ili9320_init_chip(lcd);
0109
0110     lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
0111     ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
0112
0113     return 0;
0114 }
0115
0116 static inline int ili9320_power_off(struct ili9320 *lcd)
0117 {
0118     lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
0119     ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
0120
0121     return 0;
0122 }
0123
0124 #define POWER_IS_ON(pwr)    ((pwr) <= FB_BLANK_NORMAL)
0125
0126 static int ili9320_power(struct ili9320 *lcd, int power)
0127 {
0128     int ret = 0;
0129
0130     dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
0131
0132     if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
0133         ret = ili9320_power_on(lcd);
0134     else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
0135         ret = ili9320_power_off(lcd);
0136
0137     if (ret == 0)
0138         lcd->power = power;
0139     else
0140         dev_warn(lcd->dev, "failed to set power mode %d\n", power);
0141
0142     return ret;
0143 }
0144
0145 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
0146 {
0147     return lcd_get_data(lcd);
0148 }
0149
0150 static int ili9320_set_power(struct lcd_device *ld, int power)
0151 {
0152     struct ili9320 *lcd = to_our_lcd(ld);
0153
0154     return ili9320_power(lcd, power);
0155 }
0156
0157 static int ili9320_get_power(struct lcd_device *ld)
0158 {
0159     struct ili9320 *lcd = to_our_lcd(ld);
0160
0161     return lcd->power;
0162 }
0163
0164 static struct lcd_ops ili9320_ops = {
0165     .get_power  = ili9320_get_power,
0166     .set_power  = ili9320_set_power,
0167 };
0168
0169 static void ili9320_setup_spi(struct ili9320 *ili,
0170                     struct spi_device *dev)
0171 {
0172     struct ili9320_spi *spi = &ili->access.spi;
0173
0174     ili->write = ili9320_write_spi;
0175     spi->dev = dev;
0176
0177     /* fill the two messages we are going to use to send the data
0178      * with, the first the address followed by the data. The datasheet
0179      * says they should be done as two distinct cycles of the SPI CS line.
0180      */
0181
0182     spi->xfer[0].tx_buf = spi->buffer_addr;
0183     spi->xfer[1].tx_buf = spi->buffer_data;
0184     spi->xfer[0].len = 3;
0185     spi->xfer[1].len = 3;
0186     spi->xfer[0].bits_per_word = 8;
0187     spi->xfer[1].bits_per_word = 8;
0188     spi->xfer[0].cs_change = 1;
0189
0190     spi_message_init(&spi->message);
0191     spi_message_add_tail(&spi->xfer[0], &spi->message);
0192     spi_message_add_tail(&spi->xfer[1], &spi->message);
0193 }
0194
0195 int ili9320_probe_spi(struct spi_device *spi,
0196                 struct ili9320_client *client)
0197 {
0198     struct ili9320_platdata *cfg = dev_get_platdata(&spi->dev);
0199     struct device *dev = &spi->dev;
0200     struct ili9320 *ili;
0201     struct lcd_device *lcd;
0202     int ret = 0;
0203
0204     /* verify we where given some information */
0205
0206     if (cfg == NULL) {
0207         dev_err(dev, "no platform data supplied\n");
0208         return -EINVAL;
0209     }
0210
0211     if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
0212         dev_err(dev, "invalid platform data supplied\n");
0213         return -EINVAL;
0214     }
0215
0216     /* allocate and initialse our state */
0217
0218     ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
0219     if (ili == NULL)
0220         return -ENOMEM;
0221
0222     ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
0223
0224     ili->dev = dev;
0225     ili->client = client;
0226     ili->power = FB_BLANK_POWERDOWN;
0227     ili->platdata = cfg;
0228
0229     spi_set_drvdata(spi, ili);
0230
0231     ili9320_setup_spi(ili, spi);
0232
0233     lcd = devm_lcd_device_register(&spi->dev, "ili9320", dev, ili,
0234                     &ili9320_ops);
0235     if (IS_ERR(lcd)) {
0236         dev_err(dev, "failed to register lcd device\n");
0237         return PTR_ERR(lcd);
0238     }
0239
0240     ili->lcd = lcd;
0241
0242     dev_info(dev, "initialising %s\n", client->name);
0243
0244     ret = ili9320_power(ili, FB_BLANK_UNBLANK);
0245     if (ret != 0) {
0246         dev_err(dev, "failed to set lcd power state\n");
0247         return ret;
0248     }
0249
0250     return 0;
0251 }
0252 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
0253
0254 void ili9320_remove(struct ili9320 *ili)
0255 {
0256     ili9320_power(ili, FB_BLANK_POWERDOWN);
0257 }
0258 EXPORT_SYMBOL_GPL(ili9320_remove);
0259
0260 #ifdef CONFIG_PM_SLEEP
0261 int ili9320_suspend(struct ili9320 *lcd)
0262 {
0263     int ret;
0264
0265     ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
0266
0267     if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
0268         ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
0269                   ILI9320_POWER1_SLP |
0270                   ILI9320_POWER1_DSTB);
0271         lcd->initialised = 0;
0272     }
0273
0274     return ret;
0275 }
0276 EXPORT_SYMBOL_GPL(ili9320_suspend);
0277
0278 int ili9320_resume(struct ili9320 *lcd)
0279 {
0280     dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
0281
0282     if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
0283         ili9320_write(lcd, ILI9320_POWER1, 0x00);
0284
0285     return ili9320_power(lcd, FB_BLANK_UNBLANK);
0286 }
0287 EXPORT_SYMBOL_GPL(ili9320_resume);
0288 #endif
0289
0290 /* Power down all displays on reboot, poweroff or halt */
0291 void ili9320_shutdown(struct ili9320 *lcd)
0292 {
0293     ili9320_power(lcd, FB_BLANK_POWERDOWN);
0294 }
0295 EXPORT_SYMBOL_GPL(ili9320_shutdown);
0296
0297 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
0298 MODULE_DESCRIPTION("ILI9320 LCD Driver");
0299 MODULE_LICENSE("GPL v2");