c440eee1a7
This switches the fbtft driver to use GPIO descriptors rather than numerical gpios: Utilize the GPIO library's intrinsic handling of OF GPIOs and polarity. If the line is flagged active low, gpiolib will deal with this. Remove gpios from platform device structure. Neither assign statically numbers to gpios in platform device nor allow gpios to be parsed as module parameters. Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
161 lines
3.5 KiB
C
161 lines
3.5 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* FB driver for the TLS8204 LCD Controller
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*
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* The display is monochrome and the video memory is RGB565.
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* Any pixel value except 0 turns the pixel on.
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*
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* Copyright (C) 2013 Noralf Tronnes
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* Copyright (C) 2014 Michael Hope (adapted for the TLS8204)
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/gpio/consumer.h>
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#include <linux/spi/spi.h>
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#include <linux/delay.h>
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#include "fbtft.h"
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#define DRVNAME "fb_tls8204"
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#define WIDTH 84
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#define HEIGHT 48
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#define TXBUFLEN WIDTH
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/* gamma is used to control contrast in this driver */
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#define DEFAULT_GAMMA "40"
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static unsigned int bs = 4;
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module_param(bs, uint, 0000);
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MODULE_PARM_DESC(bs, "BS[2:0] Bias voltage level: 0-7 (default: 4)");
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static int init_display(struct fbtft_par *par)
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{
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par->fbtftops.reset(par);
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/* Enter extended command mode */
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write_reg(par, 0x21); /* 5:1 1
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* 2:0 PD - Powerdown control: chip is active
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* 1:0 V - Entry mode: horizontal addressing
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* 0:1 H - Extended instruction set control:
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* extended
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*/
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/* H=1 Bias system */
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write_reg(par, 0x10 | (bs & 0x7));
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/* 4:1 1
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* 3:0 0
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* 2:x BS2 - Bias System
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* 1:x BS1
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* 0:x BS0
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*/
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/* Set the address of the first display line. */
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write_reg(par, 0x04 | (64 >> 6));
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write_reg(par, 0x40 | (64 & 0x3F));
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/* Enter H=0 standard command mode */
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write_reg(par, 0x20);
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/* H=0 Display control */
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write_reg(par, 0x08 | 4);
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/* 3:1 1
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* 2:1 D - DE: 10=normal mode
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* 1:0 0
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* 0:0 E
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*/
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return 0;
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}
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static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
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{
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/* H=0 Set X address of RAM */
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write_reg(par, 0x80); /* 7:1 1
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* 6-0: X[6:0] - 0x00
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*/
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/* H=0 Set Y address of RAM */
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write_reg(par, 0x40); /* 7:0 0
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* 6:1 1
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* 2-0: Y[2:0] - 0x0
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*/
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}
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static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
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{
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u16 *vmem16 = (u16 *)par->info->screen_buffer;
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int x, y, i;
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int ret = 0;
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for (y = 0; y < HEIGHT / 8; y++) {
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u8 *buf = par->txbuf.buf;
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/* The display is 102x68 but the LCD is 84x48.
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* Set the write pointer at the start of each row.
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*/
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gpiod_set_value(par->gpio.dc, 0);
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write_reg(par, 0x80 | 0);
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write_reg(par, 0x40 | y);
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for (x = 0; x < WIDTH; x++) {
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u8 ch = 0;
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for (i = 0; i < 8 * WIDTH; i += WIDTH) {
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ch >>= 1;
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if (vmem16[(y * 8 * WIDTH) + i + x])
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ch |= 0x80;
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}
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*buf++ = ch;
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}
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/* Write the row */
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gpiod_set_value(par->gpio.dc, 1);
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ret = par->fbtftops.write(par, par->txbuf.buf, WIDTH);
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if (ret < 0) {
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dev_err(par->info->device,
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"write failed and returned: %d\n", ret);
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break;
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}
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}
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return ret;
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}
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static int set_gamma(struct fbtft_par *par, u32 *curves)
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{
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/* apply mask */
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curves[0] &= 0x7F;
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write_reg(par, 0x21); /* turn on extended instruction set */
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write_reg(par, 0x80 | curves[0]);
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write_reg(par, 0x20); /* turn off extended instruction set */
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return 0;
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}
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static struct fbtft_display display = {
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.regwidth = 8,
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.width = WIDTH,
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.height = HEIGHT,
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.txbuflen = TXBUFLEN,
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.gamma_num = 1,
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.gamma_len = 1,
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.gamma = DEFAULT_GAMMA,
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.fbtftops = {
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.init_display = init_display,
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.set_addr_win = set_addr_win,
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.write_vmem = write_vmem,
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.set_gamma = set_gamma,
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},
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.backlight = 1,
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};
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FBTFT_REGISTER_DRIVER(DRVNAME, "teralane,tls8204", &display);
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MODULE_ALIAS("spi:" DRVNAME);
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MODULE_ALIAS("spi:tls8204");
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MODULE_DESCRIPTION("FB driver for the TLS8204 LCD Controller");
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MODULE_AUTHOR("Michael Hope");
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MODULE_LICENSE("GPL");
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