/*
 * Universal Flash Storage Host controller Platform bus based glue driver
 *
 * This code is based on drivers/scsi/ufs/ufshcd-pltfrm.c
 * Copyright (C) 2011-2013 Samsung India Software Operations
 *
 * Authors:
 *      Santosh Yaraganavi <santosh.sy@samsung.com>
 *      Vinayak Holikatti <h.vinayak@samsung.com>
 *
 * 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.
 * See the COPYING file in the top-level directory or visit
 * <http://www.gnu.org/licenses/gpl-2.0.html>
 *
 * 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.
 *
 * This program is provided "AS IS" and "WITH ALL FAULTS" and
 * without warranty of any kind. You are solely responsible for
 * determining the appropriateness of using and distributing
 * the program and assume all risks associated with your exercise
 * of rights with respect to the program, including but not limited
 * to infringement of third party rights, the risks and costs of
 * program errors, damage to or loss of data, programs or equipment,
 * and unavailability or interruption of operations. Under no
 * circumstances will the contributor of this Program be liable for
 * any damages of any kind arising from your use or distribution of
 * this program.
 */

#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>

#include "ufshcd.h"
#include "ufshcd-pltfrm.h"

#define UFSHCD_DEFAULT_LANES_PER_DIRECTION              2

static int ufshcd_parse_clock_info(struct ufs_hba *hba)
{
        int ret = 0;
        int cnt;
        int i;
        struct device *dev = hba->dev;
        struct device_node *np = dev->of_node;
        char *name;
        u32 *clkfreq = NULL;
        struct ufs_clk_info *clki;
        int len = 0;
        size_t sz = 0;

        if (!np)
                goto out;

        INIT_LIST_HEAD(&hba->clk_list_head);

        cnt = of_property_count_strings(np, "clock-names");
        if (!cnt || (cnt == -EINVAL)) {
                dev_info(dev, "%s: Unable to find clocks, assuming enabled\n",
                                __func__);
        } else if (cnt < 0) {
                dev_err(dev, "%s: count clock strings failed, err %d\n",
                                __func__, cnt);
                ret = cnt;
        }

        if (cnt <= 0)
                goto out;

        if (!of_get_property(np, "freq-table-hz", &len)) {
                dev_info(dev, "freq-table-hz property not specified\n");
                goto out;
        }

        if (len <= 0)
                goto out;

        sz = len / sizeof(*clkfreq);
        if (sz != 2 * cnt) {
                dev_err(dev, "%s len mismatch\n", "freq-table-hz");
                ret = -EINVAL;
                goto out;
        }

        clkfreq = devm_kzalloc(dev, sz * sizeof(*clkfreq),
                        GFP_KERNEL);
        if (!clkfreq) {
                ret = -ENOMEM;
                goto out;
        }

        ret = of_property_read_u32_array(np, "freq-table-hz",
                        clkfreq, sz);
        if (ret && (ret != -EINVAL)) {
                dev_err(dev, "%s: error reading array %d\n",
                                "freq-table-hz", ret);
                return ret;
        }

        for (i = 0; i < sz; i += 2) {
                ret = of_property_read_string_index(np,
                                "clock-names", i/2, (const char **)&name);
                if (ret)
                        goto out;

                clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL);
                if (!clki) {
                        ret = -ENOMEM;
                        goto out;
                }

                clki->min_freq = clkfreq[i];
                clki->max_freq = clkfreq[i+1];
                clki->name = kstrdup(name, GFP_KERNEL);
                dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
                                clki->min_freq, clki->max_freq, clki->name);
                list_add_tail(&clki->list, &hba->clk_list_head);
        }
out:
        return ret;
}

#define MAX_PROP_SIZE 32
static int ufshcd_populate_vreg(struct device *dev, const char *name,
                struct ufs_vreg **out_vreg)
{
        int ret = 0;
        char prop_name[MAX_PROP_SIZE];
        struct ufs_vreg *vreg = NULL;
        struct device_node *np = dev->of_node;

        if (!np) {
                dev_err(dev, "%s: non DT initialization\n", __func__);
                goto out;
        }

        snprintf(prop_name, MAX_PROP_SIZE, "%s-supply", name);
        if (!of_parse_phandle(np, prop_name, 0)) {
                dev_info(dev, "%s: Unable to find %s regulator, assuming enabled\n",
                                __func__, prop_name);
                goto out;
        }

        vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
        if (!vreg)
                return -ENOMEM;

        vreg->name = kstrdup(name, GFP_KERNEL);

        /* if fixed regulator no need further initialization */
        snprintf(prop_name, MAX_PROP_SIZE, "%s-fixed-regulator", name);
        if (of_property_read_bool(np, prop_name))
                goto out;

        snprintf(prop_name, MAX_PROP_SIZE, "%s-max-microamp", name);
        ret = of_property_read_u32(np, prop_name, &vreg->max_uA);
        if (ret) {
                dev_err(dev, "%s: unable to find %s err %d\n",
                                __func__, prop_name, ret);
                goto out_free;
        }

        vreg->min_uA = 0;
        if (!strcmp(name, "vcc")) {
                if (of_property_read_bool(np, "vcc-supply-1p8")) {
                        vreg->min_uV = UFS_VREG_VCC_1P8_MIN_UV;
                        vreg->max_uV = UFS_VREG_VCC_1P8_MAX_UV;
                } else {
                        vreg->min_uV = UFS_VREG_VCC_MIN_UV;
                        vreg->max_uV = UFS_VREG_VCC_MAX_UV;
                }
        } else if (!strcmp(name, "vccq")) {
                vreg->min_uV = UFS_VREG_VCCQ_MIN_UV;
                vreg->max_uV = UFS_VREG_VCCQ_MAX_UV;
        } else if (!strcmp(name, "vccq2")) {
                vreg->min_uV = UFS_VREG_VCCQ2_MIN_UV;
                vreg->max_uV = UFS_VREG_VCCQ2_MAX_UV;
        }

        goto out;

out_free:
        devm_kfree(dev, vreg);
        vreg = NULL;
out:
        if (!ret)
                *out_vreg = vreg;
        return ret;
}

/**
 * ufshcd_parse_regulator_info - get regulator info from device tree
 * @hba: per adapter instance
 *
 * Get regulator info from device tree for vcc, vccq, vccq2 power supplies.
 * If any of the supplies are not defined it is assumed that they are always-on
 * and hence return zero. If the property is defined but parsing is failed
 * then return corresponding error.
 */
static int ufshcd_parse_regulator_info(struct ufs_hba *hba)
{
        int err;
        struct device *dev = hba->dev;
        struct ufs_vreg_info *info = &hba->vreg_info;

        err = ufshcd_populate_vreg(dev, "vdd-hba", &info->vdd_hba);
        if (err)
                goto out;

        err = ufshcd_populate_vreg(dev, "vcc", &info->vcc);
        if (err)
                goto out;

        err = ufshcd_populate_vreg(dev, "vccq", &info->vccq);
        if (err)
                goto out;

        err = ufshcd_populate_vreg(dev, "vccq2", &info->vccq2);
out:
        return err;
}

#ifdef CONFIG_PM
/**
 * ufshcd_pltfrm_suspend - suspend power management function
 * @dev: pointer to device handle
 *
 * Returns 0 if successful
 * Returns non-zero otherwise
 */
int ufshcd_pltfrm_suspend(struct device *dev)
{
        return ufshcd_system_suspend(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_suspend);

/**
 * ufshcd_pltfrm_resume - resume power management function
 * @dev: pointer to device handle
 *
 * Returns 0 if successful
 * Returns non-zero otherwise
 */
int ufshcd_pltfrm_resume(struct device *dev)
{
        return ufshcd_system_resume(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_resume);

int ufshcd_pltfrm_runtime_suspend(struct device *dev)
{
        return ufshcd_runtime_suspend(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_suspend);

int ufshcd_pltfrm_runtime_resume(struct device *dev)
{
        return ufshcd_runtime_resume(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_resume);

int ufshcd_pltfrm_runtime_idle(struct device *dev)
{
        return ufshcd_runtime_idle(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_idle);

#endif /* CONFIG_PM */

void ufshcd_pltfrm_shutdown(struct platform_device *pdev)
{
        ufshcd_shutdown((struct ufs_hba *)platform_get_drvdata(pdev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_shutdown);

static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
{
        struct device *dev = hba->dev;
        int ret;

        ret = of_property_read_u32(dev->of_node, "lanes-per-direction",
                &hba->lanes_per_direction);
        if (ret) {
                dev_dbg(hba->dev,
                        "%s: failed to read lanes-per-direction, ret=%d\n",
                        __func__, ret);
                hba->lanes_per_direction = UFSHCD_DEFAULT_LANES_PER_DIRECTION;
        }
}

/**
 * ufshcd_pltfrm_init - probe routine of the driver
 * @pdev: pointer to Platform device handle
 * @vops: pointer to variant ops
 *
 * Returns 0 on success, non-zero value on failure
 */
int ufshcd_pltfrm_init(struct platform_device *pdev,
                       struct ufs_hba_variant_ops *vops)
{
        struct ufs_hba *hba;
        void __iomem *mmio_base;
        struct resource *mem_res;
        int irq, err;
        struct device *dev = &pdev->dev;

        mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        mmio_base = devm_ioremap_resource(dev, mem_res);
        if (IS_ERR(*(void **)&mmio_base)) {
                err = PTR_ERR(*(void **)&mmio_base);
                goto out;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                dev_err(dev, "IRQ resource not available\n");
                err = -ENODEV;
                goto out;
        }

        err = ufshcd_alloc_host(dev, &hba);
        if (err) {
                dev_err(&pdev->dev, "Allocation failed\n");
                goto out;
        }

        hba->vops = vops;

        err = ufshcd_parse_clock_info(hba);
        if (err) {
                dev_err(&pdev->dev, "%s: clock parse failed %d\n",
                                __func__, err);
                goto dealloc_host;
        }
        err = ufshcd_parse_regulator_info(hba);
        if (err) {
                dev_err(&pdev->dev, "%s: regulator init failed %d\n",
                                __func__, err);
                goto dealloc_host;
        }

        pm_runtime_set_active(&pdev->dev);
        pm_runtime_enable(&pdev->dev);

        ufshcd_init_lanes_per_dir(hba);

        err = ufshcd_init(hba, mmio_base, irq);
        if (err) {
                dev_err(dev, "Initialization failed\n");
                goto out_disable_rpm;
        }

        platform_set_drvdata(pdev, hba);

        return 0;

out_disable_rpm:
        pm_runtime_disable(&pdev->dev);
        pm_runtime_set_suspended(&pdev->dev);
dealloc_host:
        ufshcd_dealloc_host(hba);
out:
        return err;
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_init);

MODULE_AUTHOR("Santosh Yaragnavi <santosh.sy@samsung.com>");
MODULE_AUTHOR("Vinayak Holikatti <h.vinayak@samsung.com>");
MODULE_DESCRIPTION("UFS host controller Platform bus based glue driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(UFSHCD_DRIVER_VERSION);