From cccb6d3c149603b9c15d3c460dff317455df1766 Mon Sep 17 00:00:00 2001
From: Ben Dooks <ben-linux@fluff.org>
Date: Wed, 23 Jul 2008 21:31:37 -0700
Subject: fb: add support for the ILI9320 video display controller

Provide support for the ILI9320 display controller chip which is found in
many LCD displays.  Included with this is support for an example LCD using
this chip, the VGG2432A4.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 drivers/video/backlight/ili9320.c | 330 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 330 insertions(+)
 create mode 100644 drivers/video/backlight/ili9320.c

(limited to 'drivers/video/backlight/ili9320.c')

diff --git a/drivers/video/backlight/ili9320.c b/drivers/video/backlight/ili9320.c
new file mode 100644
index 0000000..ba89b41
--- /dev/null
+++ b/drivers/video/backlight/ili9320.c
@@ -0,0 +1,330 @@
+/* drivers/video/backlight/ili9320.c
+ *
+ * ILI9320 LCD controller driver core.
+ *
+ * Copyright 2007 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/lcd.h>
+#include <linux/module.h>
+
+#include <linux/spi/spi.h>
+
+#include <video/ili9320.h>
+
+#include "ili9320.h"
+
+
+static inline int ili9320_write_spi(struct ili9320 *ili,
+				    unsigned int reg,
+				    unsigned int value)
+{
+	struct ili9320_spi *spi = &ili->access.spi;
+	unsigned char *addr = spi->buffer_addr;
+	unsigned char *data = spi->buffer_data;
+
+	/* spi message consits of:
+	 * first byte: ID and operation
+	 */
+
+	addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
+	addr[1] = reg >> 8;
+	addr[2] = reg;
+
+	/* second message is the data to transfer */
+
+	data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
+ 	data[1] = value >> 8;
+	data[2] = value;
+
+	return spi_sync(spi->dev, &spi->message);
+}
+
+int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
+{
+	dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
+	return ili->write(ili, reg, value);
+}
+
+EXPORT_SYMBOL_GPL(ili9320_write);
+
+int ili9320_write_regs(struct ili9320 *ili,
+		       struct ili9320_reg *values,
+		       int nr_values)
+{
+	int index;
+	int ret;
+
+	for (index = 0; index < nr_values; index++, values++) {
+		ret = ili9320_write(ili, values->address, values->value);
+		if (ret != 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(ili9320_write_regs);
+
+static void ili9320_reset(struct ili9320 *lcd)
+{
+	struct ili9320_platdata *cfg = lcd->platdata;
+
+	cfg->reset(1);
+	mdelay(50);
+
+	cfg->reset(0);
+	mdelay(50);
+
+	cfg->reset(1);
+	mdelay(100);
+}
+
+static inline int ili9320_init_chip(struct ili9320 *lcd)
+{
+	int ret;
+
+	ili9320_reset(lcd);
+
+	ret = lcd->client->init(lcd, lcd->platdata);
+	if (ret != 0) {
+		dev_err(lcd->dev, "failed to initialise display\n");
+		return ret;
+	}
+
+	lcd->initialised = 1;
+	return 0;
+}
+
+static inline int ili9320_power_on(struct ili9320 *lcd)
+{
+	if (!lcd->initialised)
+		ili9320_init_chip(lcd);
+
+	lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
+	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
+
+	return 0;
+}
+
+static inline int ili9320_power_off(struct ili9320 *lcd)
+{
+	lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
+	ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
+
+	return 0;
+}
+
+#define POWER_IS_ON(pwr)	((pwr) <= FB_BLANK_NORMAL)
+
+static int ili9320_power(struct ili9320 *lcd, int power)
+{
+	int ret = 0;
+
+	dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
+
+	if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
+		ret = ili9320_power_on(lcd);
+	else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
+		ret = ili9320_power_off(lcd);
+
+	if (ret == 0)
+		lcd->power = power;
+	else
+		dev_warn(lcd->dev, "failed to set power mode %d\n", power);
+
+	return ret;
+}
+
+static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
+{
+	return lcd_get_data(lcd);
+}
+
+static int ili9320_set_power(struct lcd_device *ld, int power)
+{
+	struct ili9320 *lcd = to_our_lcd(ld);
+
+	return ili9320_power(lcd, power);
+}
+
+static int ili9320_get_power(struct lcd_device *ld)
+{
+	struct ili9320 *lcd = to_our_lcd(ld);
+
+	return lcd->power;
+}
+
+static struct lcd_ops ili9320_ops = {
+	.get_power	= ili9320_get_power,
+	.set_power	= ili9320_set_power,
+};
+
+static void __devinit ili9320_setup_spi(struct ili9320 *ili,
+					struct spi_device *dev)
+{
+	struct ili9320_spi *spi = &ili->access.spi;
+
+	ili->write = ili9320_write_spi;
+	spi->dev = dev;
+
+	/* fill the two messages we are going to use to send the data
+	 * with, the first the address followed by the data. The datasheet
+	 * says they should be done as two distinct cycles of the SPI CS line.
+	 */
+
+	spi->xfer[0].tx_buf = spi->buffer_addr;
+	spi->xfer[1].tx_buf = spi->buffer_data;
+	spi->xfer[0].len = 3;
+	spi->xfer[1].len = 3;
+	spi->xfer[0].bits_per_word = 8;
+	spi->xfer[1].bits_per_word = 8;
+	spi->xfer[0].cs_change = 1;
+
+	spi_message_init(&spi->message);
+	spi_message_add_tail(&spi->xfer[0], &spi->message);
+	spi_message_add_tail(&spi->xfer[1], &spi->message);
+}
+
+int __devinit ili9320_probe_spi(struct spi_device *spi,
+				struct ili9320_client *client)
+{
+	struct ili9320_platdata *cfg = spi->dev.platform_data;
+	struct device *dev = &spi->dev;
+	struct ili9320 *ili;
+	struct lcd_device *lcd;
+	int ret = 0;
+
+	/* verify we where given some information */
+
+	if (cfg == NULL) {
+		dev_err(dev, "no platform data supplied\n");
+		return -EINVAL;
+	}
+
+	if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
+		dev_err(dev, "invalid platform data supplied\n");
+		return -EINVAL;
+	}
+
+	/* allocate and initialse our state */
+
+	ili = kzalloc(sizeof(struct ili9320), GFP_KERNEL);
+	if (ili == NULL) {
+		dev_err(dev, "no memory for device\n");
+		return -ENOMEM;
+	}
+
+	ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
+
+	ili->dev = dev;
+	ili->client = client;
+	ili->power = FB_BLANK_POWERDOWN;
+	ili->platdata = cfg;
+
+	dev_set_drvdata(&spi->dev, ili);
+
+	ili9320_setup_spi(ili, spi);
+
+	lcd = lcd_device_register("ili9320", dev, ili, &ili9320_ops);
+	if (IS_ERR(lcd)) {
+		dev_err(dev, "failed to register lcd device\n");
+		ret = PTR_ERR(lcd);
+		goto err_free;
+	}
+
+	ili->lcd = lcd;
+
+	dev_info(dev, "initialising %s\n", client->name);
+
+	ret = ili9320_power(ili, FB_BLANK_UNBLANK);
+	if (ret != 0) {
+		dev_err(dev, "failed to set lcd power state\n");
+		goto err_unregister;
+	}
+
+	return 0;
+
+ err_unregister:
+	lcd_device_unregister(lcd);
+
+ err_free:
+	kfree(ili);
+
+	return ret;
+}
+
+EXPORT_SYMBOL_GPL(ili9320_probe_spi);
+
+int __devexit ili9320_remove(struct ili9320 *ili)
+{
+	ili9320_power(ili, FB_BLANK_POWERDOWN);
+
+	lcd_device_unregister(ili->lcd);
+	kfree(ili);
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(ili9320_remove);
+
+#ifdef CONFIG_PM
+int ili9320_suspend(struct ili9320 *lcd, pm_message_t state)
+{
+	int ret;
+
+	dev_dbg(lcd->dev, "%s: event %d\n", __func__, state.event);
+
+	if (state.event == PM_EVENT_SUSPEND) {
+		ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
+
+		if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
+			ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
+				      ILI9320_POWER1_SLP |
+				      ILI9320_POWER1_DSTB);
+			lcd->initialised = 0;
+		}
+
+		return ret;
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(ili9320_suspend);
+
+int ili9320_resume(struct ili9320 *lcd)
+{
+	dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
+
+	if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
+		ili9320_write(lcd, ILI9320_POWER1, 0x00);
+	}
+
+	return ili9320_power(lcd, FB_BLANK_UNBLANK);
+}
+
+EXPORT_SYMBOL_GPL(ili9320_resume);
+#endif
+
+/* Power down all displays on reboot, poweroff or halt */
+void ili9320_shutdown(struct ili9320 *lcd)
+{
+	ili9320_power(lcd, FB_BLANK_POWERDOWN);
+}
+
+EXPORT_SYMBOL_GPL(ili9320_shutdown);
+
+MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
+MODULE_DESCRIPTION("ILI9320 LCD Driver");
+MODULE_LICENSE("GPL v2");
-- 
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