drivers/staging/wilc1000/linux_wlan_spi.c

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/cdev.h>
#include <linux/uaccess.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/of_gpio.h>

#include "linux_wlan_spi.h"
#include "wilc_wfi_netdevice.h"
#include "linux_wlan_common.h"
#include "wilc_wlan_if.h"

#define USE_SPI_DMA     0       /* johnny add */

static const struct wilc1000_ops wilc1000_spi_ops;

static int wilc_bus_probe(struct spi_device *spi)
{
	int ret, gpio;
	struct wilc *wilc;

	gpio = of_get_gpio(spi->dev.of_node, 0);
	if (gpio < 0)
		gpio = GPIO_NUM;

	ret = wilc_netdev_init(&wilc, NULL, HIF_SPI, GPIO_NUM, &wilc_hif_spi);
	if (ret)
		return ret;

	spi_set_drvdata(spi, wilc);
	wilc->dev = &spi->dev;

	return 0;
}

static int wilc_bus_remove(struct spi_device *spi)
{
	wilc_netdev_cleanup(spi_get_drvdata(spi));
	return 0;
}

static const struct of_device_id wilc1000_of_match[] = {
	{ .compatible = "atmel,wilc_spi", },
	{}
};
MODULE_DEVICE_TABLE(of, wilc1000_of_match);

struct spi_driver wilc1000_spi_driver = {
	.driver = {
		.name = MODALIAS,
		.of_match_table = wilc1000_of_match,
	},
	.probe =  wilc_bus_probe,
	.remove = wilc_bus_remove,
};
module_spi_driver(wilc1000_spi_driver);
MODULE_LICENSE("GPL");

int wilc_spi_init(void)
{
	return 1;
}

int wilc_spi_write(u8 *b, u32 len)
{
	struct spi_device *spi = to_spi_device(wilc_dev->dev);
	int ret;
	struct spi_message msg;

	if (len > 0 && b != NULL) {
		struct spi_transfer tr = {
			.tx_buf = b,
			.len = len,
			.delay_usecs = 0,
		};
		char *r_buffer = kzalloc(len, GFP_KERNEL);
		if (!r_buffer)
			return -ENOMEM;

		tr.rx_buf = r_buffer;
		PRINT_D(BUS_DBG, "Request writing %d bytes\n", len);

		memset(&msg, 0, sizeof(msg));
		spi_message_init(&msg);
/* [[johnny add */
		msg.spi = spi;
		msg.is_dma_mapped = USE_SPI_DMA;
/* ]] */
		spi_message_add_tail(&tr, &msg);

		ret = spi_sync(spi, &msg);
		if (ret < 0) {
			PRINT_ER("SPI transaction failed\n");
		}

		kfree(r_buffer);
	} else {
		PRINT_ER("can't write data with the following length: %d\n", len);
		PRINT_ER("FAILED due to NULL buffer or ZERO length check the following length: %d\n", len);
		ret = -1;
	}

	/* change return value to match WILC interface */
	(ret < 0) ? (ret = 0) : (ret = 1);


	return ret;
}

int wilc_spi_read(u8 *rb, u32 rlen)
{
	struct spi_device *spi = to_spi_device(wilc_dev->dev);
	int ret;

	if (rlen > 0) {
		struct spi_message msg;
		struct spi_transfer tr = {
			.rx_buf = rb,
			.len = rlen,
			.delay_usecs = 0,

		};
		char *t_buffer = kzalloc(rlen, GFP_KERNEL);
		if (!t_buffer)
			return -ENOMEM;

		tr.tx_buf = t_buffer;

		memset(&msg, 0, sizeof(msg));
		spi_message_init(&msg);
/* [[ johnny add */
		msg.spi = spi;
		msg.is_dma_mapped = USE_SPI_DMA;
/* ]] */
		spi_message_add_tail(&tr, &msg);

		ret = spi_sync(spi, &msg);
		if (ret < 0) {
			PRINT_ER("SPI transaction failed\n");
		}
		kfree(t_buffer);
	} else {
		PRINT_ER("can't read data with the following length: %u\n", rlen);
		ret = -1;
	}
	/* change return value to match WILC interface */
	(ret < 0) ? (ret = 0) : (ret = 1);

	return ret;
}

int wilc_spi_write_read(u8 *wb, u8 *rb, u32 rlen)
{
	struct spi_device *spi = to_spi_device(wilc_dev->dev);
	int ret;

	if (rlen > 0) {
		struct spi_message msg;
		struct spi_transfer tr = {
			.rx_buf = rb,
			.tx_buf = wb,
			.len = rlen,
			.bits_per_word = 8,
			.delay_usecs = 0,

		};

		memset(&msg, 0, sizeof(msg));
		spi_message_init(&msg);
		msg.spi = spi;
		msg.is_dma_mapped = USE_SPI_DMA;

		spi_message_add_tail(&tr, &msg);
		ret = spi_sync(spi, &msg);
		if (ret < 0) {
			PRINT_ER("SPI transaction failed\n");
		}
	} else {
		PRINT_ER("can't read data with the following length: %u\n", rlen);
		ret = -1;
	}
	/* change return value to match WILC interface */
	(ret < 0) ? (ret = 0) : (ret = 1);

	return ret;
}