--- /dev/null
+/*
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#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,
+ "%s: write() failed and returned %d\n", __func__, 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_base + offset);
+ u16 *pos = par->txbuf.buf + 1;
+ u16 *buf16 = par->txbuf.buf + 10;
+ int i, j;
+ int ret = 0;
+
+ fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s()\n", __func__);
+
+ 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_base + offset);
+ u16 *pos = par->txbuf.buf + 1;
+ u8 *buf8 = par->txbuf.buf + 10;
+ int i, j;
+ int ret = 0;
+
+ fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s()\n", __func__);
+
+ 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;
+
+ fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+ /* enable SPI interface by having CS and MOSI low during reset */
+ save_mode = par->spi->mode;
+ par->spi->mode |= SPI_CS_HIGH;
+ ret = par->spi->master->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 = par->spi->master->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;
+
+ fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+ /* 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 void register_chip_backlight(struct fbtft_par *par)
+{
+ struct backlight_device *bd;
+ struct backlight_properties bl_props = { 0, };
+ struct backlight_ops *bl_ops;
+
+ fbtft_par_dbg(DEBUG_BACKLIGHT, par, "%s()\n", __func__);
+
+ bl_ops = devm_kzalloc(par->info->device, sizeof(struct backlight_ops),
+ GFP_KERNEL);
+ if (!bl_ops) {
+ dev_err(par->info->device,
+ "%s: could not allocate memory for backlight operations.\n",
+ __func__);
+ return;
+ }
+
+ bl_ops->update_status = backlight_chip_update_status;
+ 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");