drivers/staging/fbtft/fb_watterott.c - kernel/quantenna - Git at Google

 /*
  * FB driver for the Watterott LCD Controller
  *
  * Copyright (C) 2013 Noralf Tronnes
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>

 #include "fbtft.h"

 #define DRVNAME			"fb_watterott"
 #define WIDTH			320
 #define HEIGHT			240
 #define FPS			5
 #define TXBUFLEN		1024
 #define DEFAULT_BRIGHTNESS	50

 #define CMD_VERSION		0x01
 #define CMD_LCD_LED		0x10
 #define CMD_LCD_RESET		0x11
 #define CMD_LCD_ORIENTATION	0x20
 #define CMD_LCD_DRAWIMAGE	0x27
 #define COLOR_RGB323		8
 #define COLOR_RGB332		9
 #define COLOR_RGB233		10
 #define COLOR_RGB565		16

 static short mode = 565;
 module_param(mode, short, 0);
 MODULE_PARM_DESC(mode, "RGB color transfer mode: 332, 565 (default)");

 static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
 {
 	va_list args;
 	int i, ret;
 	u8 *buf = par->buf;

 	va_start(args, len);
 	for (i = 0; i < len; i++)
 		*buf++ = (u8)va_arg(args, unsigned int);
 	va_end(args);

 	fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par,
 		par->info->device, u8, par->buf, len, "%s: ", __func__);

 	ret = par->fbtftops.write(par, par->buf, len);
 	if (ret < 0) {
 		dev_err(par->info->device,
 			"write() failed and returned %d\n", ret);
 		return;
 	}
 }

 static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
 {
 	unsigned start_line, end_line;
 	u16 *vmem16 = (u16 *)(par->info->screen_buffer + offset);
 	u16 *pos = par->txbuf.buf + 1;
 	u16 *buf16 = par->txbuf.buf + 10;
 	int i, j;
 	int ret = 0;

 	start_line = offset / par->info->fix.line_length;
 	end_line = start_line + (len / par->info->fix.line_length) - 1;

 	/* Set command header. pos: x, y, w, h */
 	((u8 *)par->txbuf.buf)[0] = CMD_LCD_DRAWIMAGE;
 	pos[0] = 0;
 	pos[2] = cpu_to_be16(par->info->var.xres);
 	pos[3] = cpu_to_be16(1);
 	((u8 *)par->txbuf.buf)[9] = COLOR_RGB565;

 	for (i = start_line; i <= end_line; i++) {
 		pos[1] = cpu_to_be16(i);
 		for (j = 0; j < par->info->var.xres; j++)
 			buf16[j] = cpu_to_be16(*vmem16++);
 		ret = par->fbtftops.write(par,
 			par->txbuf.buf, 10 + par->info->fix.line_length);
 		if (ret < 0)
 			return ret;
 		udelay(300);
 	}

 	return 0;
 }

 #define RGB565toRGB323(c) (((c&0xE000)>>8) | ((c&0600)>>6) | ((c&0x001C)>>2))
 #define RGB565toRGB332(c) (((c&0xE000)>>8) | ((c&0700)>>6) | ((c&0x0018)>>3))
 #define RGB565toRGB233(c) (((c&0xC000)>>8) | ((c&0700)>>5) | ((c&0x001C)>>2))

 static int write_vmem_8bit(struct fbtft_par *par, size_t offset, size_t len)
 {
 	unsigned start_line, end_line;
 	u16 *vmem16 = (u16 *)(par->info->screen_buffer + offset);
 	u16 *pos = par->txbuf.buf + 1;
 	u8 *buf8 = par->txbuf.buf + 10;
 	int i, j;
 	int ret = 0;

 	start_line = offset / par->info->fix.line_length;
 	end_line = start_line + (len / par->info->fix.line_length) - 1;

 	/* Set command header. pos: x, y, w, h */
 	((u8 *)par->txbuf.buf)[0] = CMD_LCD_DRAWIMAGE;
 	pos[0] = 0;
 	pos[2] = cpu_to_be16(par->info->var.xres);
 	pos[3] = cpu_to_be16(1);
 	((u8 *)par->txbuf.buf)[9] = COLOR_RGB332;

 	for (i = start_line; i <= end_line; i++) {
 		pos[1] = cpu_to_be16(i);
 		for (j = 0; j < par->info->var.xres; j++) {
 			buf8[j] = RGB565toRGB332(*vmem16);
 			vmem16++;
 		}
 		ret = par->fbtftops.write(par,
 			par->txbuf.buf, 10 + par->info->var.xres);
 		if (ret < 0)
 			return ret;
 		udelay(700);
 	}

 	return 0;
 }

 static unsigned firmware_version(struct fbtft_par *par)
 {
 	u8 rxbuf[4] = {0, };

 	write_reg(par, CMD_VERSION);
 	par->fbtftops.read(par, rxbuf, 4);
 	if (rxbuf[1] != '.')
 		return 0;

 	return (rxbuf[0] - '0') << 8 | (rxbuf[2] - '0') << 4 | (rxbuf[3] - '0');
 }

 static int init_display(struct fbtft_par *par)
 {
 	int ret;
 	unsigned version;
 	u8 save_mode;

 	/* enable SPI interface by having CS and MOSI low during reset */
 	save_mode = par->spi->mode;
 	par->spi->mode |= SPI_CS_HIGH;
 	ret = spi_setup(par->spi); /* set CS inactive low */
 	if (ret) {
 		dev_err(par->info->device, "Could not set SPI_CS_HIGH\n");
 		return ret;
 	}
 	write_reg(par, 0x00); /* make sure mode is set */

 	mdelay(50);
 	par->fbtftops.reset(par);
 	mdelay(1000);
 	par->spi->mode = save_mode;
 	ret = spi_setup(par->spi);
 	if (ret) {
 		dev_err(par->info->device, "Could not restore SPI mode\n");
 		return ret;
 	}
 	write_reg(par, 0x00);

 	version = firmware_version(par);
 	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "Firmware version: %x.%02x\n",
 						version >> 8, version & 0xFF);

 	if (mode == 332)
 		par->fbtftops.write_vmem = write_vmem_8bit;
 	return 0;
 }

 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
 {
 	/* not used on this controller */
 }

 static int set_var(struct fbtft_par *par)
 {
 	u8 rotate;

 	/* this controller rotates clock wise */
 	switch (par->info->var.rotate) {
 	case 90:
 		rotate = 27;
 		break;
 	case 180:
 		rotate = 18;
 		break;
 	case 270:
 		rotate = 9;
 		break;
 	default:
 		rotate = 0;
 	}
 	write_reg(par, CMD_LCD_ORIENTATION, rotate);

 	return 0;
 }

 static int verify_gpios(struct fbtft_par *par)
 {
 	if (par->gpio.reset < 0) {
 		dev_err(par->info->device, "Missing 'reset' gpio. Aborting.\n");
 		return -EINVAL;
 	}
 	return 0;
 }

 #ifdef CONFIG_FB_BACKLIGHT
 static int backlight_chip_update_status(struct backlight_device *bd)
 {
 	struct fbtft_par *par = bl_get_data(bd);
 	int brightness = bd->props.brightness;

 	fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 		"%s: brightness=%d, power=%d, fb_blank=%d\n",
 		__func__, bd->props.brightness, bd->props.power,
 		bd->props.fb_blank);

 	if (bd->props.power != FB_BLANK_UNBLANK)
 		brightness = 0;

 	if (bd->props.fb_blank != FB_BLANK_UNBLANK)
 		brightness = 0;

 	write_reg(par, CMD_LCD_LED, brightness);

 	return 0;
 }

 static const struct backlight_ops bl_ops = {
 	.update_status = backlight_chip_update_status,
 };

 static void register_chip_backlight(struct fbtft_par *par)
 {
 	struct backlight_device *bd;
 	struct backlight_properties bl_props = { 0, };

 	bl_props.type = BACKLIGHT_RAW;
 	bl_props.power = FB_BLANK_POWERDOWN;
 	bl_props.max_brightness = 100;
 	bl_props.brightness = DEFAULT_BRIGHTNESS;

 	bd = backlight_device_register(dev_driver_string(par->info->device),
 				par->info->device, par, &bl_ops, &bl_props);
 	if (IS_ERR(bd)) {
 		dev_err(par->info->device,
 			"cannot register backlight device (%ld)\n",
 			PTR_ERR(bd));
 		return;
 	}
 	par->info->bl_dev = bd;

 	if (!par->fbtftops.unregister_backlight)
 		par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 }
 #else
 #define register_chip_backlight NULL
 #endif

 static struct fbtft_display display = {
 	.regwidth = 8,
 	.buswidth = 8,
 	.width = WIDTH,
 	.height = HEIGHT,
 	.fps = FPS,
 	.txbuflen = TXBUFLEN,
 	.fbtftops = {
 		.write_register = write_reg8_bus8,
 		.write_vmem = write_vmem,
 		.init_display = init_display,
 		.set_addr_win = set_addr_win,
 		.set_var = set_var,
 		.verify_gpios = verify_gpios,
 		.register_backlight = register_chip_backlight,
 	},
 };

 FBTFT_REGISTER_DRIVER(DRVNAME, "watterott,openlcd", &display);

 MODULE_ALIAS("spi:" DRVNAME);

 MODULE_DESCRIPTION("FB driver for the Watterott LCD Controller");
 MODULE_AUTHOR("Noralf Tronnes");
 MODULE_LICENSE("GPL");
	/*
	* FB driver for the Watterott LCD Controller
	*
	* Copyright (C) 2013 Noralf Tronnes
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/gpio.h>
	#include <linux/delay.h>

	#include "fbtft.h"

	#define DRVNAME "fb_watterott"
	#define WIDTH 320
	#define HEIGHT 240
	#define FPS 5
	#define TXBUFLEN 1024
	#define DEFAULT_BRIGHTNESS 50

	#define CMD_VERSION 0x01
	#define CMD_LCD_LED 0x10
	#define CMD_LCD_RESET 0x11
	#define CMD_LCD_ORIENTATION 0x20
	#define CMD_LCD_DRAWIMAGE 0x27
	#define COLOR_RGB323 8
	#define COLOR_RGB332 9
	#define COLOR_RGB233 10
	#define COLOR_RGB565 16

	static short mode = 565;
	module_param(mode, short, 0);
	MODULE_PARM_DESC(mode, "RGB color transfer mode: 332, 565 (default)");

	static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
	{
	va_list args;
	int i, ret;
	u8 *buf = par->buf;

	va_start(args, len);
	for (i = 0; i < len; i++)
	*buf++ = (u8)va_arg(args, unsigned int);
	va_end(args);

	fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par,
	par->info->device, u8, par->buf, len, "%s: ", __func__);

	ret = par->fbtftops.write(par, par->buf, len);
	if (ret < 0) {
	dev_err(par->info->device,
	"write() failed and returned %d\n", ret);
	return;
	}
	}

	static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
	{
	unsigned start_line, end_line;
	u16 vmem16 = (u16 )(par->info->screen_buffer + offset);
	u16 *pos = par->txbuf.buf + 1;
	u16 *buf16 = par->txbuf.buf + 10;
	int i, j;
	int ret = 0;

	start_line = offset / par->info->fix.line_length;
	end_line = start_line + (len / par->info->fix.line_length) - 1;

	/* Set command header. pos: x, y, w, h */
	((u8 *)par->txbuf.buf)[0] = CMD_LCD_DRAWIMAGE;
	pos[0] = 0;
	pos[2] = cpu_to_be16(par->info->var.xres);
	pos[3] = cpu_to_be16(1);
	((u8 *)par->txbuf.buf)[9] = COLOR_RGB565;

	for (i = start_line; i <= end_line; i++) {
	pos[1] = cpu_to_be16(i);
	for (j = 0; j < par->info->var.xres; j++)
	buf16[j] = cpu_to_be16(*vmem16++);
	ret = par->fbtftops.write(par,
	par->txbuf.buf, 10 + par->info->fix.line_length);
	if (ret < 0)
	return ret;
	udelay(300);
	}

	return 0;
	}

	#define RGB565toRGB323(c) (((c&0xE000)>>8) \| ((c&0600)>>6) \| ((c&0x001C)>>2))
	#define RGB565toRGB332(c) (((c&0xE000)>>8) \| ((c&0700)>>6) \| ((c&0x0018)>>3))
	#define RGB565toRGB233(c) (((c&0xC000)>>8) \| ((c&0700)>>5) \| ((c&0x001C)>>2))

	static int write_vmem_8bit(struct fbtft_par *par, size_t offset, size_t len)
	{
	unsigned start_line, end_line;
	u16 vmem16 = (u16 )(par->info->screen_buffer + offset);
	u16 *pos = par->txbuf.buf + 1;
	u8 *buf8 = par->txbuf.buf + 10;
	int i, j;
	int ret = 0;

	start_line = offset / par->info->fix.line_length;
	end_line = start_line + (len / par->info->fix.line_length) - 1;

	/* Set command header. pos: x, y, w, h */
	((u8 *)par->txbuf.buf)[0] = CMD_LCD_DRAWIMAGE;
	pos[0] = 0;
	pos[2] = cpu_to_be16(par->info->var.xres);
	pos[3] = cpu_to_be16(1);
	((u8 *)par->txbuf.buf)[9] = COLOR_RGB332;

	for (i = start_line; i <= end_line; i++) {
	pos[1] = cpu_to_be16(i);
	for (j = 0; j < par->info->var.xres; j++) {
	buf8[j] = RGB565toRGB332(*vmem16);
	vmem16++;
	}
	ret = par->fbtftops.write(par,
	par->txbuf.buf, 10 + par->info->var.xres);
	if (ret < 0)
	return ret;
	udelay(700);
	}

	return 0;
	}

	static unsigned firmware_version(struct fbtft_par *par)
	{
	u8 rxbuf[4] = {0, };

	write_reg(par, CMD_VERSION);
	par->fbtftops.read(par, rxbuf, 4);
	if (rxbuf[1] != '.')
	return 0;

	return (rxbuf[0] - '0') << 8 \| (rxbuf[2] - '0') << 4 \| (rxbuf[3] - '0');
	}

	static int init_display(struct fbtft_par *par)
	{
	int ret;
	unsigned version;
	u8 save_mode;

	/* enable SPI interface by having CS and MOSI low during reset */
	save_mode = par->spi->mode;
	par->spi->mode \|= SPI_CS_HIGH;
	ret = spi_setup(par->spi); /* set CS inactive low */
	if (ret) {
	dev_err(par->info->device, "Could not set SPI_CS_HIGH\n");
	return ret;
	}
	write_reg(par, 0x00); /* make sure mode is set */

	mdelay(50);
	par->fbtftops.reset(par);
	mdelay(1000);
	par->spi->mode = save_mode;
	ret = spi_setup(par->spi);
	if (ret) {
	dev_err(par->info->device, "Could not restore SPI mode\n");
	return ret;
	}
	write_reg(par, 0x00);

	version = firmware_version(par);
	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "Firmware version: %x.%02x\n",
	version >> 8, version & 0xFF);

	if (mode == 332)
	par->fbtftops.write_vmem = write_vmem_8bit;
	return 0;
	}

	static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
	{
	/* not used on this controller */
	}

	static int set_var(struct fbtft_par *par)
	{
	u8 rotate;

	/* this controller rotates clock wise */
	switch (par->info->var.rotate) {
	case 90:
	rotate = 27;
	break;
	case 180:
	rotate = 18;
	break;
	case 270:
	rotate = 9;
	break;
	default:
	rotate = 0;
	}
	write_reg(par, CMD_LCD_ORIENTATION, rotate);

	return 0;
	}

	static int verify_gpios(struct fbtft_par *par)
	{
	if (par->gpio.reset < 0) {
	dev_err(par->info->device, "Missing 'reset' gpio. Aborting.\n");
	return -EINVAL;
	}
	return 0;
	}

	#ifdef CONFIG_FB_BACKLIGHT
	static int backlight_chip_update_status(struct backlight_device *bd)
	{
	struct fbtft_par *par = bl_get_data(bd);
	int brightness = bd->props.brightness;

	fbtft_par_dbg(DEBUG_BACKLIGHT, par,
	"%s: brightness=%d, power=%d, fb_blank=%d\n",
	__func__, bd->props.brightness, bd->props.power,
	bd->props.fb_blank);

	if (bd->props.power != FB_BLANK_UNBLANK)
	brightness = 0;

	if (bd->props.fb_blank != FB_BLANK_UNBLANK)
	brightness = 0;

	write_reg(par, CMD_LCD_LED, brightness);

	return 0;
	}

	static const struct backlight_ops bl_ops = {
	.update_status = backlight_chip_update_status,
	};

	static void register_chip_backlight(struct fbtft_par *par)
	{
	struct backlight_device *bd;
	struct backlight_properties bl_props = { 0, };

	bl_props.type = BACKLIGHT_RAW;
	bl_props.power = FB_BLANK_POWERDOWN;
	bl_props.max_brightness = 100;
	bl_props.brightness = DEFAULT_BRIGHTNESS;

	bd = backlight_device_register(dev_driver_string(par->info->device),
	par->info->device, par, &bl_ops, &bl_props);
	if (IS_ERR(bd)) {
	dev_err(par->info->device,
	"cannot register backlight device (%ld)\n",
	PTR_ERR(bd));
	return;
	}
	par->info->bl_dev = bd;

	if (!par->fbtftops.unregister_backlight)
	par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
	}
	#else
	#define register_chip_backlight NULL
	#endif

	static struct fbtft_display display = {
	.regwidth = 8,
	.buswidth = 8,
	.width = WIDTH,
	.height = HEIGHT,
	.fps = FPS,
	.txbuflen = TXBUFLEN,
	.fbtftops = {
	.write_register = write_reg8_bus8,
	.write_vmem = write_vmem,
	.init_display = init_display,
	.set_addr_win = set_addr_win,
	.set_var = set_var,
	.verify_gpios = verify_gpios,
	.register_backlight = register_chip_backlight,
	},
	};

	FBTFT_REGISTER_DRIVER(DRVNAME, "watterott,openlcd", &display);

	MODULE_ALIAS("spi:" DRVNAME);

	MODULE_DESCRIPTION("FB driver for the Watterott LCD Controller");
	MODULE_AUTHOR("Noralf Tronnes");
	MODULE_LICENSE("GPL");