// SPDX-License-Identifier: GPL-2.0+
/*
* FB driver for the HX8347D LCD Controller
*
* Copyright (C) 2013 Christian Vogelgsang
*
* Based on driver code found here: https://github.com/watterott/r61505u-Adapter
*/
#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)
{
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)
{
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, u32 *curves)
{
unsigned long mask[] = {
0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x7f, 0x7f, 0x1f, 0x1f,
0x1f, 0x1f, 0x1f, 0x0f,
};
int i, j;
int acc = 0;
/* 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");