linux/drivers/scsi/ufs/cdns-pltfrm.c

149 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Platform UFS Host driver for Cadence controller
*
* Copyright (C) 2018 Cadence Design Systems, Inc.
*
* Authors:
* Jan Kotas <jank@cadence.com>
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/time.h>
#include "ufshcd-pltfrm.h"
#define CDNS_UFS_REG_HCLKDIV 0xFC
/**
* Sets HCLKDIV register value based on the core_clk
* @hba: host controller instance
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_set_hclkdiv(struct ufs_hba *hba)
{
struct ufs_clk_info *clki;
struct list_head *head = &hba->clk_list_head;
unsigned long core_clk_rate = 0;
u32 core_clk_div = 0;
if (list_empty(head))
return 0;
list_for_each_entry(clki, head, list) {
if (IS_ERR_OR_NULL(clki->clk))
continue;
if (!strcmp(clki->name, "core_clk"))
core_clk_rate = clk_get_rate(clki->clk);
}
if (!core_clk_rate) {
dev_err(hba->dev, "%s: unable to find core_clk rate\n",
__func__);
return -EINVAL;
}
core_clk_div = core_clk_rate / USEC_PER_SEC;
ufshcd_writel(hba, core_clk_div, CDNS_UFS_REG_HCLKDIV);
/**
* Make sure the register was updated,
* UniPro layer will not work with an incorrect value.
*/
mb();
return 0;
}
/**
* Sets clocks used by the controller
* @hba: host controller instance
* @on: if true, enable clocks, otherwise disable
* @status: notify stage (pre, post change)
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_setup_clocks(struct ufs_hba *hba, bool on,
enum ufs_notify_change_status status)
{
if ((!on) || (status == PRE_CHANGE))
return 0;
return cdns_ufs_set_hclkdiv(hba);
}
static struct ufs_hba_variant_ops cdns_pltfm_hba_vops = {
.name = "cdns-ufs-pltfm",
.setup_clocks = cdns_ufs_setup_clocks,
};
/**
* cdns_ufs_pltfrm_probe - probe routine of the driver
* @pdev: pointer to platform device handle
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_pltfrm_probe(struct platform_device *pdev)
{
int err;
struct device *dev = &pdev->dev;
/* Perform generic probe */
err = ufshcd_pltfrm_init(pdev, &cdns_pltfm_hba_vops);
if (err)
dev_err(dev, "ufshcd_pltfrm_init() failed %d\n", err);
return err;
}
/**
* cdns_ufs_pltfrm_remove - removes the ufs driver
* @pdev: pointer to platform device handle
*
* Always returns 0
*/
static int cdns_ufs_pltfrm_remove(struct platform_device *pdev)
{
struct ufs_hba *hba = platform_get_drvdata(pdev);
ufshcd_remove(hba);
return 0;
}
static const struct of_device_id cdns_ufs_of_match[] = {
{ .compatible = "cdns,ufshc" },
{},
};
MODULE_DEVICE_TABLE(of, cdns_ufs_of_match);
static const struct dev_pm_ops cdns_ufs_dev_pm_ops = {
.suspend = ufshcd_pltfrm_suspend,
.resume = ufshcd_pltfrm_resume,
.runtime_suspend = ufshcd_pltfrm_runtime_suspend,
.runtime_resume = ufshcd_pltfrm_runtime_resume,
.runtime_idle = ufshcd_pltfrm_runtime_idle,
};
static struct platform_driver cdns_ufs_pltfrm_driver = {
.probe = cdns_ufs_pltfrm_probe,
.remove = cdns_ufs_pltfrm_remove,
.driver = {
.name = "cdns-ufshcd",
.pm = &cdns_ufs_dev_pm_ops,
.of_match_table = cdns_ufs_of_match,
},
};
module_platform_driver(cdns_ufs_pltfrm_driver);
MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
MODULE_DESCRIPTION("Cadence UFS host controller platform driver");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(UFSHCD_DRIVER_VERSION);