linux-imx

/*

 * Register map access API - MMIO support

 *

 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms and conditions of the GNU General Public License,

 * version 2, as published by the Free Software Foundation.

 *

 * This program is distributed in the hope it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

 * more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

​

#include <linux/clk.h>

#include <linux/err.h>

#include <linux/io.h>

#include <linux/module.h>

#include <linux/regmap.h>

#include <linux/slab.h>

​

#include "internal.h"

​

struct regmap_mmio_context {

    void __iomem *regs;

    unsigned val_bytes;

​

    bool attached_clk;

    struct clk *clk;

​

    void (*reg_write)(struct regmap_mmio_context *ctx,

              unsigned int reg, unsigned int val);

    unsigned int (*reg_read)(struct regmap_mmio_context *ctx,

                     unsigned int reg);

};

​

static int regmap_mmio_regbits_check(size_t reg_bits)

{

    switch (reg_bits) {

    case 8:

    case 16:

    case 32:

#ifdef CONFIG_64BIT

    case 64:

#endif

        return 0;

    default:

        return -EINVAL;

    }

}

​

static int regmap_mmio_get_min_stride(size_t val_bits)

{

    int min_stride;

​

    switch (val_bits) {

    case 8:

        /* The core treats 0 as 1 */

        min_stride = 0;

        return 0;

    case 16:

        min_stride = 2;

        break;

    case 32:

        min_stride = 4;

        break;

#ifdef CONFIG_64BIT

    case 64:

        min_stride = 8;

        break;

#endif

    default:

        return -EINVAL;

    }

​

    return min_stride;

}

​

static void regmap_mmio_write8(struct regmap_mmio_context *ctx,

                unsigned int reg,

                unsigned int val)

{

    writeb(val, ctx->regs + reg);

}

​

static void regmap_mmio_write16le(struct regmap_mmio_context *ctx,

                  unsigned int reg,

                  unsigned int val)