Release 4.11 drivers/mtd/nand/socrates_nand.c

/*
 * drivers/mtd/nand/socrates_nand.c
 *
 *  Copyright © 2008 Ilya Yanok, Emcraft Systems
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/io.h>


#define FPGA_NAND_CMD_MASK		(0x7 << 28)

#define FPGA_NAND_CMD_COMMAND		(0x0 << 28)

#define FPGA_NAND_CMD_ADDR		(0x1 << 28)

#define FPGA_NAND_CMD_READ		(0x2 << 28)

#define FPGA_NAND_CMD_WRITE		(0x3 << 28)

#define FPGA_NAND_BUSY			(0x1 << 15)

#define FPGA_NAND_ENABLE		(0x1 << 31)

#define FPGA_NAND_DATA_SHIFT		16


struct socrates_nand_host {
	
struct nand_chip	nand_chip;
	
void __iomem		*io_base;
	
struct device		*dev;
};

/**
 * socrates_nand_write_buf -  write buffer to chip
 * @mtd:        MTD device structure
 * @buf:        data buffer
 * @len:        number of bytes to write
 */


static void socrates_nand_write_buf(struct mtd_info *mtd,
		const uint8_t *buf, int len)
{
	int i;
	struct nand_chip *this = mtd_to_nand(mtd);
	struct socrates_nand_host *host = nand_get_controller_data(this);

	for (i = 0; i < len; i++) {
		out_be32(host->io_base, FPGA_NAND_ENABLE |
				FPGA_NAND_CMD_WRITE |
				(buf[i] << FPGA_NAND_DATA_SHIFT));
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
71
92.21%
1
33.33%
Boris Brezillon
6
7.79%
2
66.67%
Total
77
100.00%
3
100.00%

/**
 * socrates_nand_read_buf -  read chip data into buffer
 * @mtd:        MTD device structure
 * @buf:        buffer to store date
 * @len:        number of bytes to read
 */


static void socrates_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
	int i;
	struct nand_chip *this = mtd_to_nand(mtd);
	struct socrates_nand_host *host = nand_get_controller_data(this);
	uint32_t val;

	val = FPGA_NAND_ENABLE | FPGA_NAND_CMD_READ;

	out_be32(host->io_base, val);
	for (i = 0; i < len; i++) {
		buf[i] = (in_be32(host->io_base) >>
				FPGA_NAND_DATA_SHIFT) & 0xff;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
86
93.48%
1
33.33%
Boris Brezillon
6
6.52%
2
66.67%
Total
92
100.00%
3
100.00%

/**
 * socrates_nand_read_byte -  read one byte from the chip
 * @mtd:        MTD device structure
 */


static uint8_t socrates_nand_read_byte(struct mtd_info *mtd)
{
	uint8_t byte;
	socrates_nand_read_buf(mtd, &byte, sizeof(byte));
	return byte;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
30
100.00%
1
100.00%
Total
30
100.00%
1
100.00%

/**
 * socrates_nand_read_word -  read one word from the chip
 * @mtd:        MTD device structure
 */


static uint16_t socrates_nand_read_word(struct mtd_info *mtd)
{
	uint16_t word;
	socrates_nand_read_buf(mtd, (uint8_t *)&word, sizeof(word));
	return word;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
34
100.00%
1
100.00%
Total
34
100.00%
1
100.00%

/*
 * Hardware specific access to control-lines
 */


static void socrates_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
		unsigned int ctrl)
{
	struct nand_chip *nand_chip = mtd_to_nand(mtd);
	struct socrates_nand_host *host = nand_get_controller_data(nand_chip);
	uint32_t val;

	if (cmd == NAND_CMD_NONE)
		return;

	if (ctrl & NAND_CLE)
		val = FPGA_NAND_CMD_COMMAND;
	else
		val = FPGA_NAND_CMD_ADDR;

	if (ctrl & NAND_NCE)
		val |= FPGA_NAND_ENABLE;

	val |= (cmd & 0xff) << FPGA_NAND_DATA_SHIFT;

	out_be32(host->io_base, val);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
86
93.48%
1
33.33%
Boris Brezillon
6
6.52%
2
66.67%
Total
92
100.00%
3
100.00%

/*
 * Read the Device Ready pin.
 */


static int socrates_nand_device_ready(struct mtd_info *mtd)
{
	struct nand_chip *nand_chip = mtd_to_nand(mtd);
	struct socrates_nand_host *host = nand_get_controller_data(nand_chip);

	if (in_be32(host->io_base) & FPGA_NAND_BUSY)
		return 0; /* busy */
	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
43
87.76%
1
33.33%
Boris Brezillon
6
12.24%
2
66.67%
Total
49
100.00%
3
100.00%

/*
 * Probe for the NAND device.
 */


static int socrates_nand_probe(struct platform_device *ofdev)
{
	struct socrates_nand_host *host;
	struct mtd_info *mtd;
	struct nand_chip *nand_chip;
	int res;

	/* Allocate memory for the device structure (and zero it) */
	host = devm_kzalloc(&ofdev->dev, sizeof(*host), GFP_KERNEL);
	if (!host)
		return -ENOMEM;

	host->io_base = of_iomap(ofdev->dev.of_node, 0);
	if (host->io_base == NULL) {
		dev_err(&ofdev->dev, "ioremap failed\n");
		return -EIO;
	}

	nand_chip = &host->nand_chip;
	mtd = nand_to_mtd(nand_chip);
	host->dev = &ofdev->dev;

	/* link the private data structures */
	nand_set_controller_data(nand_chip, host);
	nand_set_flash_node(nand_chip, ofdev->dev.of_node);
	mtd->name = "socrates_nand";
	mtd->dev.parent = &ofdev->dev;

	/*should never be accessed directly */
	nand_chip->IO_ADDR_R = (void *)0xdeadbeef;
	nand_chip->IO_ADDR_W = (void *)0xdeadbeef;

	nand_chip->cmd_ctrl = socrates_nand_cmd_ctrl;
	nand_chip->read_byte = socrates_nand_read_byte;
	nand_chip->read_word = socrates_nand_read_word;
	nand_chip->write_buf = socrates_nand_write_buf;
	nand_chip->read_buf = socrates_nand_read_buf;
	nand_chip->dev_ready = socrates_nand_device_ready;

	nand_chip->ecc.mode = NAND_ECC_SOFT;	/* enable ECC */
	nand_chip->ecc.algo = NAND_ECC_HAMMING;

	/* TODO: I have no idea what real delay is. */
	nand_chip->chip_delay = 20;		/* 20us command delay time */

	dev_set_drvdata(&ofdev->dev, host);

	res = nand_scan(mtd, 1);
	if (res)
		goto out;

	res = mtd_device_register(mtd, NULL, 0);
	if (!res)
		return res;

	nand_release(mtd);

out:
	iounmap(host->io_base);
	return res;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
242
80.94%
1
8.33%
Sachin Kamat
15
5.02%
2
16.67%
Brian Norris
12
4.01%
1
8.33%
Boris Brezillon
11
3.68%
2
16.67%
Rafał Miłecki
8
2.68%
1
8.33%
Masahiro Yamada
4
1.34%
1
8.33%
Anatolij Gustschin
3
1.00%
1
8.33%
Dmitry Baryshkov
3
1.00%
2
16.67%
Grant C. Likely
1
0.33%
1
8.33%
Total
299
100.00%
12
100.00%

/*
 * Remove a NAND device.
 */


static int socrates_nand_remove(struct platform_device *ofdev)
{
	struct socrates_nand_host *host = dev_get_drvdata(&ofdev->dev);
	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);

	nand_release(mtd);

	iounmap(host->io_base);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
47
90.38%
1
33.33%
Boris Brezillon
4
7.69%
1
33.33%
Grant C. Likely
1
1.92%
1
33.33%
Total
52
100.00%
3
100.00%


static const struct of_device_id socrates_nand_match[] =
{
	{
		.compatible   = "abb,socrates-nand",
        },
	{},
};

MODULE_DEVICE_TABLE(of, socrates_nand_match);


static struct platform_driver socrates_nand_driver = {
	.driver = {
		.name = "socrates_nand",
		.of_match_table = socrates_nand_match,
        },
	.probe		= socrates_nand_probe,
	.remove		= socrates_nand_remove,
};


module_platform_driver(socrates_nand_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ilya Yanok");
MODULE_DESCRIPTION("NAND driver for Socrates board");
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Wolfgang Grandegger
787
88.83%
1
5.56%
Boris Brezillon
39
4.40%
3
16.67%
Sachin Kamat
15
1.69%
2
11.11%
Brian Norris
12
1.35%
1
5.56%
Grant C. Likely
9
1.02%
3
16.67%
Rafał Miłecki
8
0.90%
1
5.56%
Masahiro Yamada
4
0.45%
1
5.56%
Dmitry Baryshkov
3
0.34%
2
11.11%
Rob Herring
3
0.34%
1
5.56%
Anatolij Gustschin
3
0.34%
1
5.56%
Axel Lin
2
0.23%
1
5.56%
Márton Németh
1
0.11%
1
5.56%
Total
886
100.00%
18
100.00%
Directory: drivers/mtd/nand

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.