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Release 4.7 drivers/staging/fbtft/fb_ssd1305.c

/*
 * FB driver for the SSD1305 OLED Controller
 *
 * based on SSD1306 driver by 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.
 */

#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_ssd1305"


#define WIDTH 128

#define HEIGHT 64

/*
 * write_reg() caveat:
 *
 *    This doesn't work because D/C has to be LOW for both values:
 *      write_reg(par, val1, val2);
 *
 *    Do it like this:
 *      write_reg(par, val1);
 *      write_reg(par, val2);
 */

/* Init sequence taken from the Adafruit SSD1306 Arduino library */

static int init_display(struct fbtft_par *par) { par->fbtftops.reset(par); if (par->gamma.curves[0] == 0) { mutex_lock(&par->gamma.lock); if (par->info->var.yres == 64) par->gamma.curves[0] = 0xCF; else par->gamma.curves[0] = 0x8F; mutex_unlock(&par->gamma.lock); } /* Set Display OFF */ write_reg(par, 0xAE); /* Set Display Clock Divide Ratio/ Oscillator Frequency */ write_reg(par, 0xD5); write_reg(par, 0x80); /* Set Multiplex Ratio */ write_reg(par, 0xA8); if (par->info->var.yres == 64) write_reg(par, 0x3F); else write_reg(par, 0x1F); /* Set Display Offset */ write_reg(par, 0xD3); write_reg(par, 0x0); /* Set Display Start Line */ write_reg(par, 0x40 | 0x0); /* Charge Pump Setting */ write_reg(par, 0x8D); /* A[2] = 1b, Enable charge pump during display on */ write_reg(par, 0x14); /* Set Memory Addressing Mode */ write_reg(par, 0x20); /* Vertical addressing mode */ write_reg(par, 0x01); /* * Set Segment Re-map * column address 127 is mapped to SEG0 */ write_reg(par, 0xA0 | ((par->info->var.rotate == 180) ? 0x0 : 0x1)); /* * Set COM Output Scan Direction * remapped mode. Scan from COM[N-1] to COM0 */ write_reg(par, ((par->info->var.rotate == 180) ? 0xC8 : 0xC0)); /* Set COM Pins Hardware Configuration */ write_reg(par, 0xDA); if (par->info->var.yres == 64) { /* A[4]=1b, Alternative COM pin configuration */ write_reg(par, 0x12); } else { /* A[4]=0b, Sequential COM pin configuration */ write_reg(par, 0x02); } /* Set Pre-charge Period */ write_reg(par, 0xD9); write_reg(par, 0xF1); /* * Entire Display ON * Resume to RAM content display. Output follows RAM content */ write_reg(par, 0xA4); /* * Set Normal Display * 0 in RAM: OFF in display panel * 1 in RAM: ON in display panel */ write_reg(par, 0xA6); /* Set Display ON */ write_reg(par, 0xAF); return 0; }

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static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) { /* Set Lower Column Start Address for Page Addressing Mode */ write_reg(par, 0x00 | ((par->info->var.rotate == 180) ? 0x0 : 0x4)); /* Set Higher Column Start Address for Page Addressing Mode */ write_reg(par, 0x10 | 0x0); /* Set Display Start Line */ write_reg(par, 0x40 | 0x0); }

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static int blank(struct fbtft_par *par, bool on) { if (on) write_reg(par, 0xAE); else write_reg(par, 0xAF); return 0; }

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/* Gamma is used to control Contrast */
static int set_gamma(struct fbtft_par *par, unsigned long *curves) { curves[0] &= 0xFF; /* Set Contrast Control for BANK0 */ write_reg(par, 0x81); write_reg(par, curves[0]); return 0; }

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static int write_vmem(struct fbtft_par *par, size_t offset, size_t len) { u16 *vmem16 = (u16 *)par->info->screen_buffer; u8 *buf = par->txbuf.buf; int x, y, i; int ret; for (x = 0; x < par->info->var.xres; x++) { for (y = 0; y < par->info->var.yres / 8; y++) { *buf = 0x00; for (i = 0; i < 8; i++) *buf |= (vmem16[(y * 8 + i) * par->info->var.xres + x] ? 1 : 0) << i; buf++; } } /* Write data */ gpio_set_value(par->gpio.dc, 1); ret = par->fbtftops.write(par, par->txbuf.buf, par->info->var.xres * par->info->var.yres / 8); if (ret < 0) dev_err(par->info->device, "write failed and returned: %d\n", ret); return ret; }

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static struct fbtft_display display = { .regwidth = 8, .width = WIDTH, .height = HEIGHT, .txbuflen = WIDTH * HEIGHT / 8, .gamma_num = 1, .gamma_len = 1, .gamma = "00", .fbtftops = { .write_vmem = write_vmem, .init_display = init_display, .set_addr_win = set_addr_win, .blank = blank, .set_gamma = set_gamma, }, }; FBTFT_REGISTER_DRIVER(DRVNAME, "solomon,ssd1305", &display); MODULE_ALIAS("spi:" DRVNAME); MODULE_ALIAS("platform:" DRVNAME); MODULE_ALIAS("spi:ssd1305"); MODULE_ALIAS("platform:ssd1305"); MODULE_DESCRIPTION("SSD1305 OLED Driver"); MODULE_AUTHOR("Alexey Mednyy"); MODULE_LICENSE("GPL");

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alexey mednyyalexey mednyy861100.00%1100.00%
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