/*
 * cs5535-mfd.c - core MFD driver for CS5535/CS5536 southbridges
 *
 * The CS5535 and CS5536 has an ISA bridge on the PCI bus that is
 * used for accessing GPIOs, MFGPTs, ACPI, etc.  Each subdevice has
 * an IO range that's specified in a single BAR.  The BAR order is
 * hardcoded in the CS553x specifications.
 *
 * Copyright (c) 2010  Andres Salomon <dilinger@queued.net>
 *
 * 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.
 *
 * This program is distributed in the hope that 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <asm/olpc.h>

#define DRV_NAME "cs5535-mfd"

enum cs5535_mfd_bars {
        SMB_BAR = 0,
        GPIO_BAR = 1,
        MFGPT_BAR = 2,
        PMS_BAR = 4,
        ACPI_BAR = 5,
        NR_BARS,
};

static int cs5535_mfd_res_enable(struct platform_device *pdev)
{
        struct resource *res;

        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
        if (!res) {
                dev_err(&pdev->dev, "can't fetch device resource info\n");
                return -EIO;
        }

        if (!request_region(res->start, resource_size(res), DRV_NAME)) {
                dev_err(&pdev->dev, "can't request region\n");
                return -EIO;
        }

        return 0;
}

static int cs5535_mfd_res_disable(struct platform_device *pdev)
{
        struct resource *res;

        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
        if (!res) {
                dev_err(&pdev->dev, "can't fetch device resource info\n");
                return -EIO;
        }

        release_region(res->start, resource_size(res));
        return 0;
}

static struct resource cs5535_mfd_resources[NR_BARS];

static struct mfd_cell cs5535_mfd_cells[] = {
        {
                .id = SMB_BAR,
                .name = "cs5535-smb",
                .num_resources = 1,
                .resources = &cs5535_mfd_resources[SMB_BAR],
        },
        {
                .id = GPIO_BAR,
                .name = "cs5535-gpio",
                .num_resources = 1,
                .resources = &cs5535_mfd_resources[GPIO_BAR],
        },
        {
                .id = MFGPT_BAR,
                .name = "cs5535-mfgpt",
                .num_resources = 1,
                .resources = &cs5535_mfd_resources[MFGPT_BAR],
        },
        {
                .id = PMS_BAR,
                .name = "cs5535-pms",
                .num_resources = 1,
                .resources = &cs5535_mfd_resources[PMS_BAR],

                .enable = cs5535_mfd_res_enable,
                .disable = cs5535_mfd_res_disable,
        },
        {
                .id = ACPI_BAR,
                .name = "cs5535-acpi",
                .num_resources = 1,
                .resources = &cs5535_mfd_resources[ACPI_BAR],

                .enable = cs5535_mfd_res_enable,
                .disable = cs5535_mfd_res_disable,
        },
};

#ifdef CONFIG_OLPC
static void cs5535_clone_olpc_cells(void)
{
        static const char *acpi_clones[] = {
                "olpc-xo1-pm-acpi",
                "olpc-xo1-sci-acpi"
        };

        if (!machine_is_olpc())
                return;

        mfd_clone_cell("cs5535-acpi", acpi_clones, ARRAY_SIZE(acpi_clones));
}
#else
static void cs5535_clone_olpc_cells(void) { }
#endif

static int cs5535_mfd_probe(struct pci_dev *pdev,
                const struct pci_device_id *id)
{
        int err, i;

        err = pci_enable_device(pdev);
        if (err)
                return err;

        /* fill in IO range for each cell; subdrivers handle the region */
        for (i = 0; i < ARRAY_SIZE(cs5535_mfd_cells); i++) {
                int bar = cs5535_mfd_cells[i].id;
                struct resource *r = &cs5535_mfd_resources[bar];

                r->flags = IORESOURCE_IO;
                r->start = pci_resource_start(pdev, bar);
                r->end = pci_resource_end(pdev, bar);

                /* id is used for temporarily storing BAR; unset it now */
                cs5535_mfd_cells[i].id = 0;
        }

        err = mfd_add_devices(&pdev->dev, -1, cs5535_mfd_cells,
                              ARRAY_SIZE(cs5535_mfd_cells), NULL, 0, NULL);
        if (err) {
                dev_err(&pdev->dev, "MFD add devices failed: %d\n", err);
                goto err_disable;
        }
        cs5535_clone_olpc_cells();

        dev_info(&pdev->dev, "%zu devices registered.\n",
                        ARRAY_SIZE(cs5535_mfd_cells));

        return 0;

err_disable:
        pci_disable_device(pdev);
        return err;
}

static void cs5535_mfd_remove(struct pci_dev *pdev)
{
        mfd_remove_devices(&pdev->dev);
        pci_disable_device(pdev);
}

static const struct pci_device_id cs5535_mfd_pci_tbl[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA) },
        { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) },
        { 0, }
};
MODULE_DEVICE_TABLE(pci, cs5535_mfd_pci_tbl);

static struct pci_driver cs5535_mfd_driver = {
        .name = DRV_NAME,
        .id_table = cs5535_mfd_pci_tbl,
        .probe = cs5535_mfd_probe,
        .remove = cs5535_mfd_remove,
};

module_pci_driver(cs5535_mfd_driver);

MODULE_AUTHOR("Andres Salomon <dilinger@queued.net>");
MODULE_DESCRIPTION("MFD driver for CS5535/CS5536 southbridge's ISA PCI device");
MODULE_LICENSE("GPL");