drivers/media/pci/solo6x10/solo6x10-gpio.c

Source file repositories/reference/linux-study-clean/drivers/media/pci/solo6x10/solo6x10-gpio.c

File Facts

System
Linux kernel
Corpus path
drivers/media/pci/solo6x10/solo6x10-gpio.c
Extension
.c
Size
4305 bytes
Lines
184
Domain
Driver Families
Bucket
drivers/media
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-or-later
/*
 * Copyright (C) 2010-2013 Bluecherry, LLC <https://www.bluecherrydvr.com>
 *
 * Original author:
 * Ben Collins <bcollins@ubuntu.com>
 *
 * Additional work by:
 * John Brooks <john.brooks@bluecherry.net>
 */

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/uaccess.h>

#include "solo6x10.h"

static void solo_gpio_mode(struct solo_dev *solo_dev,
			   unsigned int port_mask, unsigned int mode)
{
	int port;
	unsigned int ret;

	ret = solo_reg_read(solo_dev, SOLO_GPIO_CONFIG_0);

	/* To set gpio */
	for (port = 0; port < 16; port++) {
		if (!((1 << port) & port_mask))
			continue;

		ret &= (~(3 << (port << 1)));
		ret |= ((mode & 3) << (port << 1));
	}

	solo_reg_write(solo_dev, SOLO_GPIO_CONFIG_0, ret);

	/* To set extended gpio - sensor */
	ret = solo_reg_read(solo_dev, SOLO_GPIO_CONFIG_1);

	for (port = 0; port < 16; port++) {
		if (!((1UL << (port + 16)) & port_mask))
			continue;

		if (!mode)
			ret &= ~(1UL << port);
		else
			ret |= 1UL << port;
	}

	/* Enable GPIO[31:16] */
	ret |= 0xffff0000;

	solo_reg_write(solo_dev, SOLO_GPIO_CONFIG_1, ret);
}

static void solo_gpio_set(struct solo_dev *solo_dev, unsigned int value)
{
	solo_reg_write(solo_dev, SOLO_GPIO_DATA_OUT,
		       solo_reg_read(solo_dev, SOLO_GPIO_DATA_OUT) | value);
}

static void solo_gpio_clear(struct solo_dev *solo_dev, unsigned int value)
{
	solo_reg_write(solo_dev, SOLO_GPIO_DATA_OUT,
		       solo_reg_read(solo_dev, SOLO_GPIO_DATA_OUT) & ~value);
}

static void solo_gpio_config(struct solo_dev *solo_dev)
{
	/* Video reset */
	solo_gpio_mode(solo_dev, 0x30, 1);
	solo_gpio_clear(solo_dev, 0x30);
	udelay(100);
	solo_gpio_set(solo_dev, 0x30);
	udelay(100);

	/* Warning: Don't touch the next line unless you're sure of what
	 * you're doing: first four gpio [0-3] are used for video. */
	solo_gpio_mode(solo_dev, 0x0f, 2);

	/* We use bit 8-15 of SOLO_GPIO_CONFIG_0 for relay purposes */
	solo_gpio_mode(solo_dev, 0xff00, 1);

	/* Initially set relay status to 0 */
	solo_gpio_clear(solo_dev, 0xff00);

	/* Set input pins direction */
	solo_gpio_mode(solo_dev, 0xffff0000, 0);
}

Annotation

Implementation Notes