staging: fbtft: add fb_hx8347d driver

This commit adds the fb_hx8347d 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

@@ -25,3 +25,9 @@ config FB_TFT_HX8340BN
 	depends on FB_TFT
 	help
 	  Generic Framebuffer support for HX8340BN
+
+config FB_TFT_HX8347D
+	tristate "FB driver for the HX8347D LCD Controller"
+	depends on FB_TFT
+	help
+	  Generic Framebuffer support for HX8347D

drivers/staging/fbtft/Makefile

@@ -6,3 +6,4 @@ fbtft-y                          += fbtft-core.o fbtft-sysfs.o fbtft-bus.o fbtft
 obj-$(CONFIG_FB_TFT_AGM1264K_FL) += fb_agm1264k-fl.o
 obj-$(CONFIG_FB_TFT_BD663474)    += fb_bd663474.o
 obj-$(CONFIG_FB_TFT_HX8340BN)    += fb_hx8340bn.o
+obj-$(CONFIG_FB_TFT_HX8347D)     += fb_hx8347d.o

drivers/staging/fbtft/fb_hx8347d.c

+/*
+ * FB driver for the HX8347D LCD Controller
+ *
+ * Copyright (C) 2013 Christian Vogelgsang
+ *
+ * Based on driver code found here: https://github.com/watterott/r61505u-Adapter
+ *
+ * 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/delay.h>
+
+#include "fbtft.h"
+
+#define DRVNAME		"fb_hx8347d"
+#define WIDTH		320
+#define HEIGHT		240
+#define DEFAULT_GAMMA	"0 0 0 0 0 0 0 0 0 0 0 0 0 0\n" \
+			"0 0 0 0 0 0 0 0 0 0 0 0 0 0"
+
+
+static int init_display(struct fbtft_par *par)
+{
+	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+	par->fbtftops.reset(par);
+
+	/* driving ability */
+	write_reg(par, 0xEA, 0x00);
+	write_reg(par, 0xEB, 0x20);
+	write_reg(par, 0xEC, 0x0C);
+	write_reg(par, 0xED, 0xC4);
+	write_reg(par, 0xE8, 0x40);
+	write_reg(par, 0xE9, 0x38);
+	write_reg(par, 0xF1, 0x01);
+	write_reg(par, 0xF2, 0x10);
+	write_reg(par, 0x27, 0xA3);
+
+	/* power voltage */
+	write_reg(par, 0x1B, 0x1B);
+	write_reg(par, 0x1A, 0x01);
+	write_reg(par, 0x24, 0x2F);
+	write_reg(par, 0x25, 0x57);
+
+	/* VCOM offset */
+	write_reg(par, 0x23, 0x8D); /* for flicker adjust */
+
+	/* power on */
+	write_reg(par, 0x18, 0x36);
+	write_reg(par, 0x19, 0x01); /* start osc */
+	write_reg(par, 0x01, 0x00); /* wakeup */
+	write_reg(par, 0x1F, 0x88);
+	mdelay(5);
+	write_reg(par, 0x1F, 0x80);
+	mdelay(5);
+	write_reg(par, 0x1F, 0x90);
+	mdelay(5);
+	write_reg(par, 0x1F, 0xD0);
+	mdelay(5);
+
+	/* color selection */
+	write_reg(par, 0x17, 0x05); /* 65k */
+
+	/*panel characteristic */
+	write_reg(par, 0x36, 0x00);
+
+	/*display on */
+	write_reg(par, 0x28, 0x38);
+	mdelay(40);
+	write_reg(par, 0x28, 0x3C);
+
+	/* orientation */
+	write_reg(par, 0x16, 0x60 | (par->bgr << 3));
+
+	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);
+
+	write_reg(par, 0x02, (xs >> 8) & 0xFF);
+	write_reg(par, 0x03, xs & 0xFF);
+	write_reg(par, 0x04, (xe >> 8) & 0xFF);
+	write_reg(par, 0x05, xe & 0xFF);
+	write_reg(par, 0x06, (ys >> 8) & 0xFF);
+	write_reg(par, 0x07, ys & 0xFF);
+	write_reg(par, 0x08, (ye >> 8) & 0xFF);
+	write_reg(par, 0x09, ye & 0xFF);
+	write_reg(par, 0x22);
+}
+
+/*
+  Gamma string format:
+    VRP0 VRP1 VRP2 VRP3 VRP4 VRP5 PRP0 PRP1 PKP0 PKP1 PKP2 PKP3 PKP4 CGM
+    VRN0 VRN1 VRN2 VRN3 VRN4 VRN5 PRN0 PRN1 PKN0 PKN1 PKN2 PKN3 PKN4 CGM
+*/
+#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,
+		0b1111111, 0b1111111,
+		0b11111, 0b11111, 0b11111, 0b11111, 0b11111,
+		0b1111};
+	int i, j;
+	int acc = 0;
+
+	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
+
+	/* apply mask */
+	for (i = 0; i < par->gamma.num_curves; i++)
+		for (j = 0; j < par->gamma.num_values; j++) {
+			acc += CURVE(i, j);
+			CURVE(i, j) &= mask[j];
+		}
+
+	if (acc == 0) /* skip if all values are zero */
+		return 0;
+
+	for (i = 0; i < par->gamma.num_curves; i++) {
+		write_reg(par, 0x40 + (i * 0x10), CURVE(i, 0));
+		write_reg(par, 0x41 + (i * 0x10), CURVE(i, 1));
+		write_reg(par, 0x42 + (i * 0x10), CURVE(i, 2));
+		write_reg(par, 0x43 + (i * 0x10), CURVE(i, 3));
+		write_reg(par, 0x44 + (i * 0x10), CURVE(i, 4));
+		write_reg(par, 0x45 + (i * 0x10), CURVE(i, 5));
+		write_reg(par, 0x46 + (i * 0x10), CURVE(i, 6));
+		write_reg(par, 0x47 + (i * 0x10), CURVE(i, 7));
+		write_reg(par, 0x48 + (i * 0x10), CURVE(i, 8));
+		write_reg(par, 0x49 + (i * 0x10), CURVE(i, 9));
+		write_reg(par, 0x4A + (i * 0x10), CURVE(i, 10));
+		write_reg(par, 0x4B + (i * 0x10), CURVE(i, 11));
+		write_reg(par, 0x4C + (i * 0x10), CURVE(i, 12));
+	}
+	write_reg(par, 0x5D, (CURVE(1, 0) << 4) | CURVE(0, 0));
+
+	return 0;
+}
+#undef CURVE
+
+
+static struct fbtft_display display = {
+	.regwidth = 8,
+	.width = WIDTH,
+	.height = HEIGHT,
+	.gamma_num = 2,
+	.gamma_len = 14,
+	.gamma = DEFAULT_GAMMA,
+	.fbtftops = {
+		.init_display = init_display,
+		.set_addr_win = set_addr_win,
+		.set_gamma = set_gamma,
+	},
+};
+FBTFT_REGISTER_DRIVER(DRVNAME, "himax,hx8347d", &display);
+
+MODULE_ALIAS("spi:" DRVNAME);
+MODULE_ALIAS("platform:" DRVNAME);
+MODULE_ALIAS("spi:hx8347d");
+MODULE_ALIAS("platform:hx8347d");
+
+MODULE_DESCRIPTION("FB driver for the HX8347D LCD Controller");
+MODULE_AUTHOR("Christian Vogelgsang");
+MODULE_LICENSE("GPL");