drivers/staging/fbtft/fb_sh1106.c

Source file repositories/reference/linux-study-clean/drivers/staging/fbtft/fb_sh1106.c

File Facts

System
Linux kernel
Corpus path
drivers/staging/fbtft/fb_sh1106.c
Extension
.c
Size
4043 bytes
Lines
178
Domain
Driver Families
Bucket
drivers/staging
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0+
/*
 * FB driver for the SH1106 OLED Controller
 * Based on the SSD1306 driver by Noralf Tronnes
 *
 * Copyright (C) 2017 Heiner Kallweit
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.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)
{

Annotation

Implementation Notes