2 * FB driver for the HX8347D LCD Controller
4 * Copyright (C) 2013 Christian Vogelgsang
6 * Based on driver code found here: https://github.com/watterott/r61505u-Adapter
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
26 #define DRVNAME "fb_hx8347d"
29 #define DEFAULT_GAMMA "0 0 0 0 0 0 0 0 0 0 0 0 0 0\n" \
30 "0 0 0 0 0 0 0 0 0 0 0 0 0 0"
32 static int init_display(struct fbtft_par *par)
34 par->fbtftops.reset(par);
37 write_reg(par, 0xEA, 0x00);
38 write_reg(par, 0xEB, 0x20);
39 write_reg(par, 0xEC, 0x0C);
40 write_reg(par, 0xED, 0xC4);
41 write_reg(par, 0xE8, 0x40);
42 write_reg(par, 0xE9, 0x38);
43 write_reg(par, 0xF1, 0x01);
44 write_reg(par, 0xF2, 0x10);
45 write_reg(par, 0x27, 0xA3);
48 write_reg(par, 0x1B, 0x1B);
49 write_reg(par, 0x1A, 0x01);
50 write_reg(par, 0x24, 0x2F);
51 write_reg(par, 0x25, 0x57);
54 write_reg(par, 0x23, 0x8D); /* for flicker adjust */
57 write_reg(par, 0x18, 0x36);
58 write_reg(par, 0x19, 0x01); /* start osc */
59 write_reg(par, 0x01, 0x00); /* wakeup */
60 write_reg(par, 0x1F, 0x88);
62 write_reg(par, 0x1F, 0x80);
64 write_reg(par, 0x1F, 0x90);
66 write_reg(par, 0x1F, 0xD0);
70 write_reg(par, 0x17, 0x05); /* 65k */
72 /*panel characteristic */
73 write_reg(par, 0x36, 0x00);
76 write_reg(par, 0x28, 0x38);
78 write_reg(par, 0x28, 0x3C);
81 write_reg(par, 0x16, 0x60 | (par->bgr << 3));
86 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
88 write_reg(par, 0x02, (xs >> 8) & 0xFF);
89 write_reg(par, 0x03, xs & 0xFF);
90 write_reg(par, 0x04, (xe >> 8) & 0xFF);
91 write_reg(par, 0x05, xe & 0xFF);
92 write_reg(par, 0x06, (ys >> 8) & 0xFF);
93 write_reg(par, 0x07, ys & 0xFF);
94 write_reg(par, 0x08, (ye >> 8) & 0xFF);
95 write_reg(par, 0x09, ye & 0xFF);
100 * Gamma string format:
101 * VRP0 VRP1 VRP2 VRP3 VRP4 VRP5 PRP0 PRP1 PKP0 PKP1 PKP2 PKP3 PKP4 CGM
102 * VRN0 VRN1 VRN2 VRN3 VRN4 VRN5 PRN0 PRN1 PKN0 PKN1 PKN2 PKN3 PKN4 CGM
104 #define CURVE(num, idx) curves[num * par->gamma.num_values + idx]
105 static int set_gamma(struct fbtft_par *par, unsigned long *curves)
107 unsigned long mask[] = {
108 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x7f, 0x7f, 0x1f, 0x1f,
109 0x1f, 0x1f, 0x1f, 0x0f,
115 for (i = 0; i < par->gamma.num_curves; i++)
116 for (j = 0; j < par->gamma.num_values; j++) {
118 CURVE(i, j) &= mask[j];
121 if (acc == 0) /* skip if all values are zero */
124 for (i = 0; i < par->gamma.num_curves; i++) {
125 write_reg(par, 0x40 + (i * 0x10), CURVE(i, 0));
126 write_reg(par, 0x41 + (i * 0x10), CURVE(i, 1));
127 write_reg(par, 0x42 + (i * 0x10), CURVE(i, 2));
128 write_reg(par, 0x43 + (i * 0x10), CURVE(i, 3));
129 write_reg(par, 0x44 + (i * 0x10), CURVE(i, 4));
130 write_reg(par, 0x45 + (i * 0x10), CURVE(i, 5));
131 write_reg(par, 0x46 + (i * 0x10), CURVE(i, 6));
132 write_reg(par, 0x47 + (i * 0x10), CURVE(i, 7));
133 write_reg(par, 0x48 + (i * 0x10), CURVE(i, 8));
134 write_reg(par, 0x49 + (i * 0x10), CURVE(i, 9));
135 write_reg(par, 0x4A + (i * 0x10), CURVE(i, 10));
136 write_reg(par, 0x4B + (i * 0x10), CURVE(i, 11));
137 write_reg(par, 0x4C + (i * 0x10), CURVE(i, 12));
139 write_reg(par, 0x5D, (CURVE(1, 0) << 4) | CURVE(0, 0));
146 static struct fbtft_display display = {
152 .gamma = DEFAULT_GAMMA,
154 .init_display = init_display,
155 .set_addr_win = set_addr_win,
156 .set_gamma = set_gamma,
160 FBTFT_REGISTER_DRIVER(DRVNAME, "himax,hx8347d", &display);
162 MODULE_ALIAS("spi:" DRVNAME);
163 MODULE_ALIAS("platform:" DRVNAME);
164 MODULE_ALIAS("spi:hx8347d");
165 MODULE_ALIAS("platform:hx8347d");
167 MODULE_DESCRIPTION("FB driver for the HX8347D LCD Controller");
168 MODULE_AUTHOR("Christian Vogelgsang");
169 MODULE_LICENSE("GPL");