[MTD] [NAND] Add support for NAND on the Socrates board (1b578193) · Commits · e / devices / android_kernel_teracube_mt6765

drivers/mtd/nand/Kconfig

+6 −0

Original line number	Diff line number	Diff line
		@@ -440,4 +440,10 @@ config MTD_NAND_TXX9NDFMC
		help
		This enables the NAND flash controller on the TXx9 SoCs.

		config MTD_NAND_SOCRATES
		tristate "Support for NAND on Socrates board"
		depends on MTD_NAND && SOCRATES
		help
		Enables support for NAND Flash chips wired onto Socrates board.

		endif # MTD_NAND

drivers/mtd/nand/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@ obj-$(CONFIG_MTD_NAND_FSL_ELBC) += fsl_elbc_nand.o
		obj-$(CONFIG_MTD_NAND_FSL_UPM) += fsl_upm.o
		obj-$(CONFIG_MTD_NAND_SH_FLCTL) += sh_flctl.o
		obj-$(CONFIG_MTD_NAND_MXC) += mxc_nand.o
		obj-$(CONFIG_MTD_NAND_SOCRATES) += socrates_nand.o
		obj-$(CONFIG_MTD_NAND_TXX9NDFMC) += txx9ndfmc.o

		nand-objs := nand_base.o nand_bbt.o

drivers/mtd/nand/socrates_nand.c

0 → 100644

+325 −0

Original line number	Diff line number	Diff line
		/*
		* 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_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;
		struct mtd_info mtd;
		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->priv;
		struct socrates_nand_host *host = this->priv;

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

		/**
		* 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->priv;
		struct socrates_nand_host *host = this->priv;
		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;
		}
		}

		/**
		* 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;
		}

		/**
		* 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;
		}

		/**
		* socrates_nand_verify_buf - Verify chip data against buffer
		* @mtd: MTD device structure
		* @buf: buffer containing the data to compare
		* @len: number of bytes to compare
		*/
		static int socrates_nand_verify_buf(struct mtd_info mtd, const u8 buf,
		int len)
		{
		int i;

		for (i = 0; i < len; i++) {
		if (buf[i] != socrates_nand_read_byte(mtd))
		return -EFAULT;
		}
		return 0;
		}

		/*
		* 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->priv;
		struct socrates_nand_host *host = nand_chip->priv;
		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);
		}

		/*
		* Read the Device Ready pin.
		*/
		static int socrates_nand_device_ready(struct mtd_info *mtd)
		{
		struct nand_chip *nand_chip = mtd->priv;
		struct socrates_nand_host *host = nand_chip->priv;

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

		#ifdef CONFIG_MTD_PARTITIONS
		static const char *part_probes[] = { "cmdlinepart", NULL };
		#endif

		/*
		* Probe for the NAND device.
		*/
		static int __devinit socrates_nand_probe(struct of_device *ofdev,
		const struct of_device_id *ofid)
		{
		struct socrates_nand_host *host;
		struct mtd_info *mtd;
		struct nand_chip *nand_chip;
		int res;

		#ifdef CONFIG_MTD_PARTITIONS
		struct mtd_partition *partitions = NULL;
		int num_partitions = 0;
		#endif

		/* Allocate memory for the device structure (and zero it) */
		host = kzalloc(sizeof(struct socrates_nand_host), GFP_KERNEL);
		if (!host) {
		printk(KERN_ERR
		"socrates_nand: failed to allocate device structure.\n");
		return -ENOMEM;
		}

		host->io_base = of_iomap(ofdev->node, 0);
		if (host->io_base == NULL) {
		printk(KERN_ERR "socrates_nand: ioremap failed\n");
		kfree(host);
		return -EIO;
		}

		mtd = &host->mtd;
		nand_chip = &host->nand_chip;
		host->dev = &ofdev->dev;

		nand_chip->priv = host; /* link the private data structures */
		mtd->priv = nand_chip;
		mtd->name = "socrates_nand";
		mtd->owner = THIS_MODULE;
		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->verify_buf = socrates_nand_verify_buf;
		nand_chip->dev_ready = socrates_nand_device_ready;

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

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

		dev_set_drvdata(&ofdev->dev, host);

		/* first scan to find the device and get the page size */
		if (nand_scan_ident(mtd, 1)) {
		res = -ENXIO;
		goto out;
		}

		/* second phase scan */
		if (nand_scan_tail(mtd)) {
		res = -ENXIO;
		goto out;
		}

		#ifdef CONFIG_MTD_PARTITIONS
		#ifdef CONFIG_MTD_CMDLINE_PARTS
		num_partitions = parse_mtd_partitions(mtd, part_probes,
		&partitions, 0);
		if (num_partitions < 0) {
		res = num_partitions;
		goto release;
		}
		#endif

		#ifdef CONFIG_MTD_OF_PARTS
		if (num_partitions == 0) {
		num_partitions = of_mtd_parse_partitions(&ofdev->dev,
		ofdev->node,
		&partitions);
		if (num_partitions < 0) {
		res = num_partitions;
		goto release;
		}
		}
		#endif
		if (partitions && (num_partitions > 0))
		res = add_mtd_partitions(mtd, partitions, num_partitions);
		else
		#endif
		res = add_mtd_device(mtd);

		if (!res)
		return res;

		#ifdef CONFIG_MTD_PARTITIONS
		release:
		#endif
		nand_release(mtd);

		out:
		dev_set_drvdata(&ofdev->dev, NULL);
		iounmap(host->io_base);
		kfree(host);
		return res;
		}

		/*
		* Remove a NAND device.
		*/
		static int __devexit socrates_nand_remove(struct of_device *ofdev)
		{
		struct socrates_nand_host *host = dev_get_drvdata(&ofdev->dev);
		struct mtd_info *mtd = &host->mtd;

		nand_release(mtd);

		dev_set_drvdata(&ofdev->dev, NULL);
		iounmap(host->io_base);
		kfree(host);

		return 0;
		}

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

		MODULE_DEVICE_TABLE(of, socrates_nand_match);

		static struct of_platform_driver socrates_nand_driver = {
		.name = "socrates_nand",
		.match_table = socrates_nand_match,
		.probe = socrates_nand_probe,
		.remove = __devexit_p(socrates_nand_remove),
		};

		static int __init socrates_nand_init(void)
		{
		return of_register_platform_driver(&socrates_nand_driver);
		}

		static void __exit socrates_nand_exit(void)
		{
		of_unregister_platform_driver(&socrates_nand_driver);
		}

		module_init(socrates_nand_init);
		module_exit(socrates_nand_exit);

		MODULE_LICENSE("GPL");
		MODULE_AUTHOR("Ilya Yanok");
		MODULE_DESCRIPTION("NAND driver for Socrates board");