From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/staging/fbtft/fb_pcd8544.c | 189 +++++++++++++++++++++++++++++++++++++ 1 file changed, 189 insertions(+) create mode 100644 drivers/staging/fbtft/fb_pcd8544.c (limited to 'drivers/staging/fbtft/fb_pcd8544.c') diff --git a/drivers/staging/fbtft/fb_pcd8544.c b/drivers/staging/fbtft/fb_pcd8544.c new file mode 100644 index 000000000..15da0ec77 --- /dev/null +++ b/drivers/staging/fbtft/fb_pcd8544.c @@ -0,0 +1,189 @@ +/* + * FB driver for the PCD8544 LCD Controller + * + * The display is monochrome and the video memory is RGB565. + * Any pixel value except 0 turns the pixel on. + * + * Copyright (C) 2013 Noralf Tronnes + * + * 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 +#include +#include +#include +#include +#include + +#include "fbtft.h" + +#define DRVNAME "fb_pcd8544" +#define WIDTH 84 +#define HEIGHT 48 +#define TXBUFLEN (84*6) +#define DEFAULT_GAMMA "40" /* gamma controls the contrast in this driver */ + +static unsigned tc; +module_param(tc, uint, 0); +MODULE_PARM_DESC(tc, "TC[1:0] Temperature coefficient: 0-3 (default: 0)"); + +static unsigned bs = 4; +module_param(bs, uint, 0); +MODULE_PARM_DESC(bs, "BS[2:0] Bias voltage level: 0-7 (default: 4)"); + + +static int init_display(struct fbtft_par *par) +{ + fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); + + par->fbtftops.reset(par); + + /* Function set + * + * 5:1 1 + * 2:0 PD - Powerdown control: chip is active + * 1:0 V - Entry mode: horizontal addressing + * 0:1 H - Extended instruction set control: extended + */ + write_reg(par, 0x21); + + /* H=1 Temperature control + * + * 2:1 1 + * 1:x TC1 - Temperature Coefficient: 0x10 + * 0:x TC0 + */ + write_reg(par, 0x04 | (tc & 0x3)); + + /* H=1 Bias system + * + * 4:1 1 + * 3:0 0 + * 2:x BS2 - Bias System + * 1:x BS1 + * 0:x BS0 + */ + write_reg(par, 0x10 | (bs & 0x7)); + + /* Function set + * + * 5:1 1 + * 2:0 PD - Powerdown control: chip is active + * 1:1 V - Entry mode: vertical addressing + * 0:0 H - Extended instruction set control: basic + */ + write_reg(par, 0x22); + + /* H=0 Display control + * + * 3:1 1 + * 2:1 D - DE: 10=normal mode + * 1:0 0 + * 0:0 E + */ + write_reg(par, 0x08 | 4); + + 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); + + /* H=0 Set X address of RAM + * + * 7:1 1 + * 6-0: X[6:0] - 0x00 + */ + write_reg(par, 0x80); + + /* H=0 Set Y address of RAM + * + * 7:0 0 + * 6:1 1 + * 2-0: Y[2:0] - 0x0 + */ + write_reg(par, 0x40); +} + +static int write_vmem(struct fbtft_par *par, size_t offset, size_t len) +{ + u16 *vmem16 = (u16 *)par->info->screen_base; + u8 *buf = par->txbuf.buf; + int x, y, i; + int ret = 0; + + fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s()\n", __func__); + + for (x = 0; x < 84; x++) { + for (y = 0; y < 6; y++) { + *buf = 0x00; + for (i = 0; i < 8; i++) + *buf |= (vmem16[(y*8+i)*84+x] ? 1 : 0) << i; + buf++; + } + } + + /* Write data */ + gpio_set_value(par->gpio.dc, 1); + ret = par->fbtftops.write(par, par->txbuf.buf, 6*84); + if (ret < 0) + dev_err(par->info->device, "write failed and returned: %d\n", + ret); + + return ret; +} + +static int set_gamma(struct fbtft_par *par, unsigned long *curves) +{ + fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); + + /* apply mask */ + curves[0] &= 0x7F; + + write_reg(par, 0x23); /* turn on extended instruction set */ + write_reg(par, 0x80 | curves[0]); + write_reg(par, 0x22); /* turn off extended instruction set */ + + return 0; +} + + +static struct fbtft_display display = { + .regwidth = 8, + .width = WIDTH, + .height = HEIGHT, + .txbuflen = TXBUFLEN, + .gamma_num = 1, + .gamma_len = 1, + .gamma = DEFAULT_GAMMA, + .fbtftops = { + .init_display = init_display, + .set_addr_win = set_addr_win, + .write_vmem = write_vmem, + .set_gamma = set_gamma, + }, + .backlight = 1, +}; +FBTFT_REGISTER_DRIVER(DRVNAME, "philips,pdc8544", &display); + +MODULE_ALIAS("spi:" DRVNAME); +MODULE_ALIAS("spi:pdc8544"); + +MODULE_DESCRIPTION("FB driver for the PCD8544 LCD Controller"); +MODULE_AUTHOR("Noralf Tronnes"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3-54-g00ecf