kernel/drivers/scsi/ufs/ti-j721e-ufs.c
2024-07-22 17:22:30 +08:00

97 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
//
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#define TI_UFS_SS_CTRL 0x4
#define TI_UFS_SS_RST_N_PCS BIT(0)
#define TI_UFS_SS_CLK_26MHZ BIT(4)
static int ti_j721e_ufs_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
unsigned long clk_rate;
void __iomem *regbase;
struct clk *clk;
u32 reg = 0;
int ret;
regbase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(regbase))
return PTR_ERR(regbase);
pm_runtime_enable(dev);
ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
goto disable_pm;
/* Select MPHY refclk frequency */
clk = devm_clk_get(dev, NULL);
if (IS_ERR(clk)) {
ret = PTR_ERR(clk);
dev_err(dev, "Cannot claim MPHY clock.\n");
goto clk_err;
}
clk_rate = clk_get_rate(clk);
if (clk_rate == 26000000)
reg |= TI_UFS_SS_CLK_26MHZ;
devm_clk_put(dev, clk);
/* Take UFS slave device out of reset */
reg |= TI_UFS_SS_RST_N_PCS;
writel(reg, regbase + TI_UFS_SS_CTRL);
ret = of_platform_populate(pdev->dev.of_node, NULL, NULL,
dev);
if (ret) {
dev_err(dev, "failed to populate child nodes %d\n", ret);
goto clk_err;
}
return ret;
clk_err:
pm_runtime_put_sync(dev);
disable_pm:
pm_runtime_disable(dev);
return ret;
}
static int ti_j721e_ufs_remove(struct platform_device *pdev)
{
of_platform_depopulate(&pdev->dev);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
static const struct of_device_id ti_j721e_ufs_of_match[] = {
{
.compatible = "ti,j721e-ufs",
},
{ },
};
static struct platform_driver ti_j721e_ufs_driver = {
.probe = ti_j721e_ufs_probe,
.remove = ti_j721e_ufs_remove,
.driver = {
.name = "ti-j721e-ufs",
.of_match_table = ti_j721e_ufs_of_match,
},
};
module_platform_driver(ti_j721e_ufs_driver);
MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
MODULE_DESCRIPTION("TI UFS host controller glue driver");
MODULE_LICENSE("GPL v2");