drivers/media/i2c/s5c73m3/s5c73m3-spi.c

Source file repositories/reference/linux-study-clean/drivers/media/i2c/s5c73m3/s5c73m3-spi.c

File Facts

System
Linux kernel
Corpus path
drivers/media/i2c/s5c73m3/s5c73m3-spi.c
Extension
.c
Size
3153 bytes
Lines
148
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-only
/*
 * Samsung LSI S5C73M3 8M pixel camera driver
 *
 * Copyright (C) 2012, Samsung Electronics, Co., Ltd.
 * Sylwester Nawrocki <s.nawrocki@samsung.com>
 * Andrzej Hajda <a.hajda@samsung.com>
 */

#include <linux/sizes.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/media.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>

#include "s5c73m3.h"

#define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI"

static const struct of_device_id s5c73m3_spi_ids[] = {
	{ .compatible = "samsung,s5c73m3" },
	{ }
};
MODULE_DEVICE_TABLE(of, s5c73m3_spi_ids);

enum spi_direction {
	SPI_DIR_RX,
	SPI_DIR_TX
};

static int spi_xmit(struct spi_device *spi_dev, void *addr, const int len,
							enum spi_direction dir)
{
	struct spi_message msg;
	int r;
	struct spi_transfer xfer = {
		.len	= len,
	};

	if (dir == SPI_DIR_TX)
		xfer.tx_buf = addr;
	else
		xfer.rx_buf = addr;

	if (spi_dev == NULL) {
		pr_err("SPI device is uninitialized\n");
		return -ENODEV;
	}

	spi_message_init(&msg);
	spi_message_add_tail(&xfer, &msg);

	r = spi_sync(spi_dev, &msg);
	if (r < 0)
		dev_err(&spi_dev->dev, "%s spi_sync failed %d\n", __func__, r);

	return r;
}

int s5c73m3_spi_write(struct s5c73m3 *state, const void *addr,
		      const unsigned int len, const unsigned int tx_size)
{
	struct spi_device *spi_dev = state->spi_dev;
	u32 count = len / tx_size;
	u32 extra = len % tx_size;
	unsigned int i, j = 0;
	u8 padding[32];
	int r = 0;

	memset(padding, 0, sizeof(padding));

	for (i = 0; i < count; i++) {
		r = spi_xmit(spi_dev, (void *)addr + j, tx_size, SPI_DIR_TX);
		if (r < 0)
			return r;
		j += tx_size;
	}

	if (extra > 0) {
		r = spi_xmit(spi_dev, (void *)addr + j, extra, SPI_DIR_TX);
		if (r < 0)
			return r;
	}

	return spi_xmit(spi_dev, padding, sizeof(padding), SPI_DIR_TX);
}

int s5c73m3_spi_read(struct s5c73m3 *state, void *addr,

Annotation

Implementation Notes