cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

fb_uc1701.c (4184B)

      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * FB driver for the UC1701 LCD Controller
      4 *
      5 * The display is monochrome and the video memory is RGB565.
      6 * Any pixel value except 0 turns the pixel on.
      7 *
      8 * Copyright (C) 2014 Juergen Holzmann
      9 */
     10
     11#include <linux/module.h>
     12#include <linux/kernel.h>
     13#include <linux/init.h>
     14#include <linux/gpio/consumer.h>
     15#include <linux/spi/spi.h>
     16#include <linux/delay.h>
     17
     18#include "fbtft.h"
     19
     20#define DRVNAME	"fb_uc1701"
     21#define WIDTH	  102
     22#define HEIGHT	 64
     23#define PAGES	  (HEIGHT / 8)
     24
     25/* 1: Display on/off */
     26#define LCD_DISPLAY_ENABLE    0xAE
     27/* 2: display start line set */
     28#define LCD_START_LINE	0x40
     29/* 3: Page address set (lower 4 bits select one of the pages) */
     30#define LCD_PAGE_ADDRESS      0xB0
     31/* 4: column address */
     32#define LCD_COL_ADDRESS       0x10
     33/* 8: select orientation */
     34#define LCD_BOTTOMVIEW	0xA0
     35/* 9: inverted display */
     36#define LCD_DISPLAY_INVERT    0xA6
     37/* 10: show memory content or switch all pixels on */
     38#define LCD_ALL_PIXEL	 0xA4
     39/* 11: lcd bias set */
     40#define LCD_BIAS	      0xA2
     41/* 14: Reset Controller */
     42#define LCD_RESET_CMD	 0xE2
     43/* 15: output mode select (turns display upside-down) */
     44#define LCD_SCAN_DIR	  0xC0
     45/* 16: power control set */
     46#define LCD_POWER_CONTROL     0x28
     47/* 17: voltage regulator resistor ratio set */
     48#define LCD_VOLTAGE	   0x20
     49/* 18: Volume mode set */
     50#define LCD_VOLUME_MODE       0x81
     51/* 22: NOP command */
     52#define LCD_NO_OP	     0xE3
     53/* 25: advanced program control */
     54#define LCD_ADV_PROG_CTRL     0xFA
     55/* 25: advanced program control2 */
     56#define LCD_ADV_PROG_CTRL2    0x10
     57#define LCD_TEMPCOMP_HIGH     0x80
     58/* column offset for normal orientation */
     59#define SHIFT_ADDR_NORMAL     0
     60/* column offset for bottom view orientation */
     61#define SHIFT_ADDR_TOPVIEW    30
     62
     63static int init_display(struct fbtft_par *par)
     64{
     65	par->fbtftops.reset(par);
     66
     67	/* softreset of LCD */
     68	write_reg(par, LCD_RESET_CMD);
     69	mdelay(10);
     70
     71	/* set startpoint */
     72	write_reg(par, LCD_START_LINE);
     73
     74	/* select orientation BOTTOMVIEW */
     75	write_reg(par, LCD_BOTTOMVIEW | 1);
     76
     77	/* output mode select (turns display upside-down) */
     78	write_reg(par, LCD_SCAN_DIR | 0x00);
     79
     80	/* Normal Pixel mode */
     81	write_reg(par, LCD_ALL_PIXEL | 0);
     82
     83	/* positive display */
     84	write_reg(par, LCD_DISPLAY_INVERT | 0);
     85
     86	/* bias 1/9 */
     87	write_reg(par, LCD_BIAS | 0);
     88
     89	/* power control mode: all features on */
     90	write_reg(par, LCD_POWER_CONTROL | 0x07);
     91
     92	/* set voltage regulator R/R */
     93	write_reg(par, LCD_VOLTAGE | 0x07);
     94
     95	/* volume mode set */
     96	write_reg(par, LCD_VOLUME_MODE);
     97	write_reg(par, 0x09);
     98	write_reg(par, LCD_NO_OP);
     99
    100	/* advanced program control */
    101	write_reg(par, LCD_ADV_PROG_CTRL);
    102	write_reg(par, LCD_ADV_PROG_CTRL2 | LCD_TEMPCOMP_HIGH);
    103
    104	/* enable display */
    105	write_reg(par, LCD_DISPLAY_ENABLE | 1);
    106
    107	return 0;
    108}
    109
    110static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
    111{
    112	/* goto address */
    113	write_reg(par, LCD_PAGE_ADDRESS);
    114	write_reg(par, 0x00);
    115	write_reg(par, LCD_COL_ADDRESS);
    116}
    117
    118static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
    119{
    120	u16 *vmem16 = (u16 *)par->info->screen_buffer;
    121	u8 *buf;
    122	int x, y, i;
    123	int ret = 0;
    124
    125	for (y = 0; y < PAGES; y++) {
    126		buf = par->txbuf.buf;
    127		for (x = 0; x < WIDTH; x++) {
    128			*buf = 0x00;
    129			for (i = 0; i < 8; i++)
    130				*buf |= (vmem16[((y * 8 * WIDTH) +
    131						 (i * WIDTH)) + x] ?
    132					 1 : 0) << i;
    133			buf++;
    134		}
    135
    136		write_reg(par, LCD_PAGE_ADDRESS | (u8)y);
    137		write_reg(par, 0x00);
    138		write_reg(par, LCD_COL_ADDRESS);
    139		gpiod_set_value(par->gpio.dc, 1);
    140		ret = par->fbtftops.write(par, par->txbuf.buf, WIDTH);
    141		gpiod_set_value(par->gpio.dc, 0);
    142	}
    143
    144	if (ret < 0)
    145		dev_err(par->info->device, "write failed and returned: %d\n",
    146			ret);
    147
    148	return ret;
    149}
    150
    151static struct fbtft_display display = {
    152	.regwidth = 8,
    153	.width = WIDTH,
    154	.height = HEIGHT,
    155	.fbtftops = {
    156		.init_display = init_display,
    157		.set_addr_win = set_addr_win,
    158		.write_vmem = write_vmem,
    159	},
    160	.backlight = 1,
    161};
    162
    163FBTFT_REGISTER_DRIVER(DRVNAME, "UltraChip,uc1701", &display);
    164
    165MODULE_ALIAS("spi:" DRVNAME);
    166MODULE_ALIAS("spi:uc1701");
    167
    168MODULE_DESCRIPTION("FB driver for the UC1701 LCD Controller");
    169MODULE_AUTHOR("Juergen Holzmann");
    170MODULE_LICENSE("GPL");