staging: fbtft: add fb_s6d1121 driver

This commit adds the fb_s6d1121 driver from the fbtft project at
https://github.com/notro/fbtft.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Noralf Tronnes <notro@tronnes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fbtft/Kconfig

@@ -91,3 +91,9 @@ config FB_TFT_S6D02A1
 	depends on FB_TFT
 	help
 	  Generic Framebuffer support for S6D02A1
+
+config FB_TFT_S6D1121
+	tristate "FB driver for the S6D1211 LCD Controller"
+	depends on FB_TFT
+	help
+	  Generic Framebuffer support for S6D1121

drivers/staging/fbtft/Makefile

@@ -17,3 +17,4 @@ obj-$(CONFIG_FB_TFT_ILI9486)     += fb_ili9486.o
 obj-$(CONFIG_FB_TFT_PCD8544)     += fb_pcd8544.o
 obj-$(CONFIG_FB_TFT_RA8875)      += fb_ra8875.o
 obj-$(CONFIG_FB_TFT_S6D02A1)     += fb_s6d02a1.o
+obj-$(CONFIG_FB_TFT_S6D1121)     += fb_s6d1121.o

drivers/staging/fbtft/fb_s6d1121.c

+/*
+ * FB driver for the S6D1121 LCD Controller
+ *
+ * Copyright (C) 2013 Roman Rolinsky
+ *
+ * Based on fb_ili9325.c by Noralf Tronnes
+ * Based on ili9325.c by Jeroen Domburg
+ * Init code from UTFT library by Henning Karlsen
+ *
+ * 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_s6d1121"
+#define WIDTH		240
+#define HEIGHT		320
+#define BPP		16
+#define FPS		20
+#define DEFAULT_GAMMA	"26 09 24 2C 1F 23 24 25 22 26 25 23 0D 00\n" \
+			"1C 1A 13 1D 0B 11 12 10 13 15 36 19 00 0D"
+
+static int init_display(struct fbtft_par *par)
+{
+	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+	par->fbtftops.reset(par);
+
+	if (par->gpio.cs != -1)
+		gpio_set_value(par->gpio.cs, 0);  /* Activate chip */
+
+	/* Initialization sequence from Lib_UTFT */
+
+	write_reg(par, 0x0011, 0x2004);
+	write_reg(par, 0x0013, 0xCC00);
+	write_reg(par, 0x0015, 0x2600);
+	write_reg(par, 0x0014, 0x252A);
+	write_reg(par, 0x0012, 0x0033);
+	write_reg(par, 0x0013, 0xCC04);
+	write_reg(par, 0x0013, 0xCC06);
+	write_reg(par, 0x0013, 0xCC4F);
+	write_reg(par, 0x0013, 0x674F);
+	write_reg(par, 0x0011, 0x2003);
+	write_reg(par, 0x0016, 0x0007);
+	write_reg(par, 0x0002, 0x0013);
+	write_reg(par, 0x0003, 0x0003);
+	write_reg(par, 0x0001, 0x0127);
+	write_reg(par, 0x0008, 0x0303);
+	write_reg(par, 0x000A, 0x000B);
+	write_reg(par, 0x000B, 0x0003);
+	write_reg(par, 0x000C, 0x0000);
+	write_reg(par, 0x0041, 0x0000);
+	write_reg(par, 0x0050, 0x0000);
+	write_reg(par, 0x0060, 0x0005);
+	write_reg(par, 0x0070, 0x000B);
+	write_reg(par, 0x0071, 0x0000);
+	write_reg(par, 0x0078, 0x0000);
+	write_reg(par, 0x007A, 0x0000);
+	write_reg(par, 0x0079, 0x0007);
+	write_reg(par, 0x0007, 0x0051);
+	write_reg(par, 0x0007, 0x0053);
+	write_reg(par, 0x0079, 0x0000);
+
+	write_reg(par, 0x0022); /* Write Data to GRAM */
+
+	return 0;
+}
+
+static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
+{
+	fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par,
+		"%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", __func__, xs, ys, xe, ye);
+	switch (par->info->var.rotate) {
+	/* R20h = Horizontal GRAM Start Address */
+	/* R21h = Vertical GRAM Start Address */
+	case 0:
+		write_reg(par, 0x0020, xs);
+		write_reg(par, 0x0021, ys);
+		break;
+	case 180:
+		write_reg(par, 0x0020, WIDTH - 1 - xs);
+		write_reg(par, 0x0021, HEIGHT - 1 - ys);
+		break;
+	case 270:
+		write_reg(par, 0x0020, WIDTH - 1 - ys);
+		write_reg(par, 0x0021, xs);
+		break;
+	case 90:
+		write_reg(par, 0x0020, ys);
+		write_reg(par, 0x0021, HEIGHT - 1 - xs);
+		break;
+	}
+	write_reg(par, 0x0022); /* Write Data to GRAM */
+}
+
+static int set_var(struct fbtft_par *par)
+{
+	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+	switch (par->info->var.rotate) {
+	/* AM: GRAM update direction */
+	case 0:
+		write_reg(par, 0x03, 0x0003 | (par->bgr << 12));
+		break;
+	case 180:
+		write_reg(par, 0x03, 0x0000 | (par->bgr << 12));
+		break;
+	case 270:
+		write_reg(par, 0x03, 0x000A | (par->bgr << 12));
+		break;
+	case 90:
+		write_reg(par, 0x03, 0x0009 | (par->bgr << 12));
+		break;
+	}
+
+	return 0;
+}
+
+/*
+  Gamma string format:
+    PKP0 PKP1 PKP2 PKP3 PKP4 PKP5 PKP6 PKP7 PKP8 PKP9 PKP10 PKP11 VRP0 VRP1
+    PKN0 PKN1 PKN2 PKN3 PKN4 PKN5 PKN6 PKN7 PRN8 PRN9 PRN10 PRN11 VRN0 VRN1
+*/
+#define CURVE(num, idx)  curves[num*par->gamma.num_values + idx]
+static int set_gamma(struct fbtft_par *par, unsigned long *curves)
+{
+	unsigned long mask[] = {
+		0b111111, 0b111111, 0b111111, 0b111111, 0b111111, 0b111111, 
+		0b111111, 0b111111, 0b111111, 0b111111, 0b111111, 0b111111,
+		0b11111, 0b11111,
+		0b111111, 0b111111, 0b111111, 0b111111, 0b111111, 0b111111,
+		0b111111, 0b111111, 0b111111, 0b111111, 0b111111, 0b111111,
+		0b11111, 0b11111 };
+	int i, j;
+
+	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+	/* apply mask */
+	for (i = 0; i < 2; i++)
+		for (j = 0; j < 14; j++)
+			CURVE(i, j) &= mask[i*par->gamma.num_values + j];
+
+	write_reg(par, 0x0030, CURVE(0, 1) << 8 | CURVE(0, 0));
+	write_reg(par, 0x0031, CURVE(0, 3) << 8 | CURVE(0, 2));
+	write_reg(par, 0x0032, CURVE(0, 5) << 8 | CURVE(0, 3));
+	write_reg(par, 0x0033, CURVE(0, 7) << 8 | CURVE(0, 6));
+	write_reg(par, 0x0034, CURVE(0, 9) << 8 | CURVE(0, 8));
+	write_reg(par, 0x0035, CURVE(0, 11) << 8 | CURVE(0, 10));
+
+	write_reg(par, 0x0036, CURVE(1, 1) << 8 | CURVE(1, 0));
+	write_reg(par, 0x0037, CURVE(1, 3) << 8 | CURVE(1, 2));
+	write_reg(par, 0x0038, CURVE(1, 5) << 8 | CURVE(1, 4));
+	write_reg(par, 0x0039, CURVE(1, 7) << 8 | CURVE(1, 6));
+	write_reg(par, 0x003A, CURVE(1, 9) << 8 | CURVE(1, 8));
+	write_reg(par, 0x003B, CURVE(1, 11) << 8 | CURVE(1, 10));
+
+	write_reg(par, 0x003C, CURVE(0, 13) << 8 | CURVE(0, 12));
+	write_reg(par, 0x003D, CURVE(1, 13) << 8 | CURVE(1, 12));
+
+	return 0;
+}
+#undef CURVE
+
+
+static struct fbtft_display display = {
+	.regwidth = 16,
+	.width = WIDTH,
+	.height = HEIGHT,
+	.bpp = BPP,
+	.fps = FPS,
+	.gamma_num = 2,
+	.gamma_len = 14,
+	.gamma = DEFAULT_GAMMA,
+	.fbtftops = {
+		.init_display = init_display,
+		.set_addr_win = set_addr_win,
+		.set_var = set_var,
+		.set_gamma = set_gamma,
+	},
+};
+FBTFT_REGISTER_DRIVER(DRVNAME, "samsung,s6d1121", &display);
+
+MODULE_ALIAS("spi:" DRVNAME);
+MODULE_ALIAS("platform:" DRVNAME);
+MODULE_ALIAS("spi:s6d1121");
+MODULE_ALIAS("platform:s6d1121");
+
+MODULE_DESCRIPTION("FB driver for the S6D1121 LCD Controller");
+MODULE_AUTHOR("Roman Rolinsky");
+MODULE_LICENSE("GPL");