diff options
Diffstat (limited to 'drivers/staging/fbtft/fb_sh1106.c')
| -rw-r--r-- | drivers/staging/fbtft/fb_sh1106.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/staging/fbtft/fb_sh1106.c b/drivers/staging/fbtft/fb_sh1106.c new file mode 100644 index 0000000..89c27a4 --- /dev/null +++ b/drivers/staging/fbtft/fb_sh1106.c @@ -0,0 +1,195 @@ +/* + * FB driver for the SH1106 OLED Controller + * Based on the SSD1306 driver by Noralf Tronnes + * + * Copyright (C) 2017 Heiner Kallweit + * + * 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. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/gpio.h> +#include <linux/delay.h> + +#include "fbtft.h" + +#define DRVNAME "fb_sh1106" +#define WIDTH 128 +#define HEIGHT 64 + +/* Init sequence based on the Adafruit SSD1306 Arduino library */ +static int init_display(struct fbtft_par *par) +{ + if (!par->info->var.xres || par->info->var.xres > WIDTH || + !par->info->var.yres || par->info->var.yres > HEIGHT || + par->info->var.yres % 8) { + dev_err(par->info->device, "Invalid screen size\n"); + return -EINVAL; + } + + if (par->info->var.rotate) { + dev_err(par->info->device, "Display rotation not supported\n"); + return -EINVAL; + } + + par->fbtftops.reset(par); + + /* Set Display OFF */ + write_reg(par, 0xAE); + + /* Set Display Clock Divide Ratio/ Oscillator Frequency */ + write_reg(par, 0xD5, 0x80); + + /* Set Multiplex Ratio */ + write_reg(par, 0xA8, par->info->var.yres - 1); + + /* Set Display Offset */ + write_reg(par, 0xD3, 0x00); + + /* Set Display Start Line */ + write_reg(par, 0x40 | 0x0); + + /* Set Segment Re-map */ + /* column address 127 is mapped to SEG0 */ + write_reg(par, 0xA0 | 0x1); + + /* Set COM Output Scan Direction */ + /* remapped mode. Scan from COM[N-1] to COM0 */ + write_reg(par, 0xC8); + + /* Set COM Pins Hardware Configuration */ + if (par->info->var.yres == 64) + /* A[4]=1b, Alternative COM pin configuration */ + write_reg(par, 0xDA, 0x12); + else if (par->info->var.yres == 48) + /* A[4]=1b, Alternative COM pin configuration */ + write_reg(par, 0xDA, 0x12); + else + /* A[4]=0b, Sequential COM pin configuration */ + write_reg(par, 0xDA, 0x02); + + /* Set Pre-charge Period */ + write_reg(par, 0xD9, 0xF1); + + /* Set VCOMH Deselect Level */ + write_reg(par, 0xDB, 0x40); + + /* Set Display ON */ + write_reg(par, 0xAF); + + msleep(150); + + return 0; +} + +static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) +{ +} + +static int blank(struct fbtft_par *par, bool on) +{ + fbtft_par_dbg(DEBUG_BLANK, par, "%s(blank=%s)\n", + __func__, on ? "true" : "false"); + + write_reg(par, on ? 0xAE : 0xAF); + + return 0; +} + +/* Gamma is used to control Contrast */ +static int set_gamma(struct fbtft_par *par, u32 *curves) +{ + /* apply mask */ + curves[0] &= 0xFF; + + /* Set Contrast Control for BANK0 */ + write_reg(par, 0x81, curves[0]); + + return 0; +} + +static int write_vmem(struct fbtft_par *par, size_t offset, size_t len) +{ + u16 *vmem16 = (u16 *)par->info->screen_buffer; + u32 xres = par->info->var.xres; + int page, page_start, page_end, x, i, ret; + u8 *buf = par->txbuf.buf; + + /* offset refers to vmem with 2 bytes element size */ + page_start = offset / (8 * 2 * xres); + page_end = DIV_ROUND_UP(offset + len, 8 * 2 * xres); + + for (page = page_start; page < page_end; page++) { + /* set page and set column to 2 because of vidmem width 132 */ + write_reg(par, 0xb0 | page, 0x00 | 2, 0x10 | 0); + + memset(buf, 0, xres); + for (x = 0; x < xres; x++) + for (i = 0; i < 8; i++) + if (vmem16[(page * 8 + i) * xres + x]) + buf[x] |= BIT(i); + + /* Write data */ + ret = fbtft_write_buf_dc(par, buf, xres, 1); + if (ret < 0) + return ret; + } + + return 0; +} + +static void write_register(struct fbtft_par *par, int len, ...) +{ + va_list args; + int i; + + va_start(args, len); + + for (i = 0; i < len; i++) + par->buf[i] = va_arg(args, unsigned int); + + /* keep DC low for all command bytes to transfer */ + fbtft_write_buf_dc(par, par->buf, len, 0); + + va_end(args); +} + +static struct fbtft_display display = { + .regwidth = 8, + .width = WIDTH, + .height = HEIGHT, + .txbuflen = WIDTH, + .gamma_num = 1, + .gamma_len = 1, + /* set default contrast to 0xcd = 80% */ + .gamma = "cd", + .fbtftops = { + .write_vmem = write_vmem, + .write_register = write_register, + .init_display = init_display, + .set_addr_win = set_addr_win, + .blank = blank, + .set_gamma = set_gamma, + }, +}; + +FBTFT_REGISTER_DRIVER(DRVNAME, "sinowealth,sh1106", &display); + +MODULE_ALIAS("spi:" DRVNAME); +MODULE_ALIAS("platform:" DRVNAME); +MODULE_ALIAS("spi:sh1106"); +MODULE_ALIAS("platform:sh1106"); + +MODULE_DESCRIPTION("SH1106 OLED Driver"); +MODULE_AUTHOR("Heiner Kallweit"); +MODULE_LICENSE("GPL"); |
