i2c-designware-pcidrv.c

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/*
 * Synopsys DesignWare I2C adapter driver (master only).
 *
 * Based on the TI DAVINCI I2C adapter driver.
 *
 * Copyright (C) 2006 Texas Instruments.
 * Copyright (C) 2007 MontaVista Software Inc.
 * Copyright (C) 2009 Provigent Ltd.
 * Copyright (C) 2011 Intel corporation.
 *
 * ----------------------------------------------------------------------------
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include "i2c-designware-core.h"

#define DRIVER_NAME "i2c-designware-pci"

enum dw_pci_ctl_id_t {
    moorestown_0,
    moorestown_1,
    moorestown_2,

    medfield_0,
    medfield_1,
    medfield_2,
    medfield_3,
    medfield_4,
    medfield_5,
};

struct dw_pci_controller {
    u32 bus_num;
    u32 bus_cfg;
    u32 tx_fifo_depth;
    u32 rx_fifo_depth;
    u32 clk_khz;
};

#define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |          \
                DW_IC_CON_SLAVE_DISABLE |   \
                DW_IC_CON_RESTART_EN)

static struct  dw_pci_controller  dw_pci_controllers[] = {
    [moorestown_0] = {
        .bus_num     = 0,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [moorestown_1] = {
        .bus_num     = 1,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [moorestown_2] = {
        .bus_num     = 2,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_0] = {
        .bus_num     = 0,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_1] = {
        .bus_num     = 1,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_2] = {
        .bus_num     = 2,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_3] = {
        .bus_num     = 3,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_STD,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_4] = {
        .bus_num     = 4,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
    [medfield_5] = {
        .bus_num     = 5,
        .bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
        .tx_fifo_depth = 32,
        .rx_fifo_depth = 32,
        .clk_khz      = 25000,
    },
};
static struct i2c_algorithm i2c_dw_algo = {
    .master_xfer    = i2c_dw_xfer,
    .functionality  = i2c_dw_func,
};

static int i2c_dw_pci_suspend(struct device *dev)
{
    struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
    struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
    int err;


    i2c_dw_disable(i2c);

    err = pci_save_state(pdev);
    if (err) {
        dev_err(&pdev->dev, "pci_save_state failed\n");
        return err;
    }

    err = pci_set_power_state(pdev, PCI_D3hot);
    if (err) {
        dev_err(&pdev->dev, "pci_set_power_state failed\n");
        return err;
    }

    return 0;
}

static int i2c_dw_pci_resume(struct device *dev)
{
    struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
    struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
    int err;
    u32 enabled;

    enabled = i2c_dw_is_enabled(i2c);
    if (enabled)
        return 0;

    err = pci_set_power_state(pdev, PCI_D0);
    if (err) {
        dev_err(&pdev->dev, "pci_set_power_state() failed\n");
        return err;
    }

    pci_restore_state(pdev);

    i2c_dw_init(i2c);
    return 0;
}

static int i2c_dw_pci_runtime_idle(struct device *dev)
{
    int err = pm_schedule_suspend(dev, 500);
    dev_dbg(dev, "runtime_idle called\n");

    if (err != 0)
        return 0;
    return -EBUSY;
}

static const struct dev_pm_ops i2c_dw_pm_ops = {
    .resume         = i2c_dw_pci_resume,
    .suspend        = i2c_dw_pci_suspend,
    SET_RUNTIME_PM_OPS(i2c_dw_pci_suspend, i2c_dw_pci_resume,
               i2c_dw_pci_runtime_idle)
};

static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
{
    return dev->controller->clk_khz;
}

static int __devinit i2c_dw_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
    struct dw_i2c_dev *dev;
    struct i2c_adapter *adap;
    unsigned long start, len;
    void __iomem *base;
    int r;
    struct  dw_pci_controller *controller;

    if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
        printk(KERN_ERR "dw_i2c_pci_probe: invalid driver data %ld\n",
            id->driver_data);
        return -EINVAL;
    }

    controller = &dw_pci_controllers[id->driver_data];

    r = pci_enable_device(pdev);
    if (r) {
        dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
            r);
        goto exit;
    }

    /* Determine the address of the I2C area */
    start = pci_resource_start(pdev, 0);
    len = pci_resource_len(pdev, 0);
    if (!start || len == 0) {
        dev_err(&pdev->dev, "base address not set\n");
        r = -ENODEV;
        goto exit;
    }

    r = pci_request_region(pdev, 0, DRIVER_NAME);
    if (r) {
        dev_err(&pdev->dev, "failed to request I2C region "
            "0x%lx-0x%lx\n", start,
            (unsigned long)pci_resource_end(pdev, 0));
        goto exit;
    }

    base = ioremap_nocache(start, len);
    if (!base) {
        dev_err(&pdev->dev, "I/O memory remapping failed\n");
        r = -ENOMEM;
        goto err_release_region;
    }


    dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
    if (!dev) {
        r = -ENOMEM;
        goto err_release_region;
    }

    init_completion(&dev->cmd_complete);
    mutex_init(&dev->lock);
    dev->clk = NULL;
    dev->controller = controller;
    dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
    dev->base = base;
    dev->dev = get_device(&pdev->dev);
    dev->functionality =
        I2C_FUNC_I2C |
        I2C_FUNC_SMBUS_BYTE |
        I2C_FUNC_SMBUS_BYTE_DATA |
        I2C_FUNC_SMBUS_WORD_DATA |
        I2C_FUNC_SMBUS_I2C_BLOCK;
    dev->master_cfg =  controller->bus_cfg;

    pci_set_drvdata(pdev, dev);

    dev->tx_fifo_depth = controller->tx_fifo_depth;
    dev->rx_fifo_depth = controller->rx_fifo_depth;
    r = i2c_dw_init(dev);
    if (r)
        goto err_iounmap;

    adap = &dev->adapter;
    i2c_set_adapdata(adap, dev);
    adap->owner = THIS_MODULE;
    adap->class = 0;
    adap->algo = &i2c_dw_algo;
    adap->dev.parent = &pdev->dev;
    adap->nr = controller->bus_num;
    snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci-%d",
        adap->nr);

    r = request_irq(pdev->irq, i2c_dw_isr, IRQF_SHARED, adap->name, dev);
    if (r) {
        dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
        goto err_iounmap;
    }

    i2c_dw_disable_int(dev);
    i2c_dw_clear_int(dev);
    r = i2c_add_numbered_adapter(adap);
    if (r) {
        dev_err(&pdev->dev, "failure adding adapter\n");
        goto err_free_irq;
    }

    pm_runtime_put_noidle(&pdev->dev);
    pm_runtime_allow(&pdev->dev);

    return 0;

err_free_irq:
    free_irq(pdev->irq, dev);
err_iounmap:
    iounmap(dev->base);
    pci_set_drvdata(pdev, NULL);
    put_device(&pdev->dev);
    kfree(dev);
err_release_region:
    pci_release_region(pdev, 0);
exit:
    return r;
}

static void __devexit i2c_dw_pci_remove(struct pci_dev *pdev)
{
    struct dw_i2c_dev *dev = pci_get_drvdata(pdev);

    i2c_dw_disable(dev);
    pm_runtime_forbid(&pdev->dev);
    pm_runtime_get_noresume(&pdev->dev);

    pci_set_drvdata(pdev, NULL);
    i2c_del_adapter(&dev->adapter);
    put_device(&pdev->dev);

    free_irq(dev->irq, dev);
    kfree(dev);
    pci_release_region(pdev, 0);
}

/* work with hotplug and coldplug */
MODULE_ALIAS("i2c_designware-pci");

static DEFINE_PCI_DEVICE_TABLE(i2_designware_pci_ids) = {
    /* Moorestown */
    { PCI_VDEVICE(INTEL, 0x0802), moorestown_0 },
    { PCI_VDEVICE(INTEL, 0x0803), moorestown_1 },
    { PCI_VDEVICE(INTEL, 0x0804), moorestown_2 },
    /* Medfield */
    { PCI_VDEVICE(INTEL, 0x0817), medfield_3,},
    { PCI_VDEVICE(INTEL, 0x0818), medfield_4 },
    { PCI_VDEVICE(INTEL, 0x0819), medfield_5 },
    { PCI_VDEVICE(INTEL, 0x082C), medfield_0 },
    { PCI_VDEVICE(INTEL, 0x082D), medfield_1 },
    { PCI_VDEVICE(INTEL, 0x082E), medfield_2 },
    { 0,}
};
MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);

static struct pci_driver dw_i2c_driver = {
    .name       = DRIVER_NAME,
    .id_table   = i2_designware_pci_ids,
    .probe      = i2c_dw_pci_probe,
    .remove     = __devexit_p(i2c_dw_pci_remove),
    .driver         = {
        .pm     = &i2c_dw_pm_ops,
    },
};

module_pci_driver(dw_i2c_driver);

MODULE_AUTHOR("Baruch Siach <[email protected]>");
MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
MODULE_LICENSE("GPL");