1. 根目录:
2. arch
3. arm
4. mach-omap2
5. gpmc-nand.c

/*
 * gpmc-nand.c
 *
 * Copyright (C) 2009 Texas Instruments
 * Vimal Singh <vimalsingh@ti.com>
 *
 * 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/kernel.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/mtd/nand.h>

#include <asm/mach/flash.h>

#include <plat/cpu.h>
#include <plat/nand.h>
#include <plat/board.h>
#include <plat/gpmc.h>

static struct resource gpmc_nand_resource = {
	.flags		= IORESOURCE_MEM,
};

static struct platform_device gpmc_nand_device = {
	.name		= "omap2-nand",
	.id		= 0,
	.num_resources	= 1,
	.resource	= &gpmc_nand_resource,
};

static int omap2_nand_gpmc_retime(struct omap_nand_platform_data *gpmc_nand_data)
{
	struct gpmc_timings t;
	int err;

	if (!gpmc_nand_data->gpmc_t)
		return 0;

	memset(&t, 0, sizeof(t));
	t.sync_clk = gpmc_nand_data->gpmc_t->sync_clk;
	t.cs_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_on);
	t.adv_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->adv_on);

	/* Read */
	t.adv_rd_off = gpmc_round_ns_to_ticks(
				gpmc_nand_data->gpmc_t->adv_rd_off);
	t.oe_on  = t.adv_on;
	t.access = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->access);
	t.oe_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->oe_off);
	t.cs_rd_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_rd_off);
	t.rd_cycle  = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->rd_cycle);

	/* Write */
	t.adv_wr_off = gpmc_round_ns_to_ticks(
				gpmc_nand_data->gpmc_t->adv_wr_off);
	t.we_on  = t.oe_on;
	if (cpu_is_omap34xx()) {
	    t.wr_data_mux_bus =	gpmc_round_ns_to_ticks(
				gpmc_nand_data->gpmc_t->wr_data_mux_bus);
	    t.wr_access = gpmc_round_ns_to_ticks(
				gpmc_nand_data->gpmc_t->wr_access);
	}
	t.we_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->we_off);
	t.cs_wr_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_wr_off);
	t.wr_cycle  = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->wr_cycle);

	/* Configure GPMC */
	if (gpmc_nand_data->devsize == NAND_BUSWIDTH_16)
		gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_DEV_SIZE, 1);
	else
		gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_DEV_SIZE, 0);
	gpmc_cs_configure(gpmc_nand_data->cs,
			GPMC_CONFIG_DEV_TYPE, GPMC_DEVICETYPE_NAND);
	err = gpmc_cs_set_timings(gpmc_nand_data->cs, &t);
	if (err)
		return err;

	return 0;
}

int __init gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data)
{
	int err	= 0;
	struct device *dev = &gpmc_nand_device.dev;

	gpmc_nand_device.dev.platform_data = gpmc_nand_data;

	err = gpmc_cs_request(gpmc_nand_data->cs, NAND_IO_SIZE,
				&gpmc_nand_data->phys_base);
	if (err < 0) {
		dev_err(dev, "Cannot request GPMC CS\n");
		return err;
	}

	 /* Set timings in GPMC */
	err = omap2_nand_gpmc_retime(gpmc_nand_data);
	if (err < 0) {
		dev_err(dev, "Unable to set gpmc timings: %d\n", err);
		return err;
	}

	/* Enable RD PIN Monitoring Reg */
	if (gpmc_nand_data->dev_ready) {
		gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_RDY_BSY, 1);
	}

	err = platform_device_register(&gpmc_nand_device);
	if (err < 0) {
		dev_err(dev, "Unable to register NAND device\n");
		goto out_free_cs;
	}

	return 0;

out_free_cs:
	gpmc_cs_free(gpmc_nand_data->cs);

	return err;
}