1// SPDX-License-Identifier: GPL-2.0
2//
3// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
4//
5
6#include <linux/clk.h>
7#include <linux/io.h>
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/of_platform.h>
11#include <linux/platform_device.h>
12#include <linux/pm_runtime.h>
13
14#define TI_UFS_SS_CTRL 0x4
15#define TI_UFS_SS_RST_N_PCS BIT(0)
16#define TI_UFS_SS_CLK_26MHZ BIT(4)
17
18static int ti_j721e_ufs_probe(struct platform_device *pdev)
19{
20 struct device *dev = &pdev->dev;
21 unsigned long clk_rate;
22 void __iomem *regbase;
23 struct clk *clk;
24 u32 reg = 0;
25 int ret;
26
27 regbase = devm_platform_ioremap_resource(pdev, index: 0);
28 if (IS_ERR(ptr: regbase))
29 return PTR_ERR(ptr: regbase);
30
31 pm_runtime_enable(dev);
32 ret = pm_runtime_resume_and_get(dev);
33 if (ret < 0)
34 goto disable_pm;
35
36 /* Select MPHY refclk frequency */
37 clk = devm_clk_get(dev, NULL);
38 if (IS_ERR(ptr: clk)) {
39 ret = PTR_ERR(ptr: clk);
40 dev_err(dev, "Cannot claim MPHY clock.\n");
41 goto clk_err;
42 }
43 clk_rate = clk_get_rate(clk);
44 if (clk_rate == 26000000)
45 reg |= TI_UFS_SS_CLK_26MHZ;
46 devm_clk_put(dev, clk);
47
48 /* Take UFS slave device out of reset */
49 reg |= TI_UFS_SS_RST_N_PCS;
50 writel(val: reg, addr: regbase + TI_UFS_SS_CTRL);
51
52 ret = of_platform_populate(root: pdev->dev.of_node, NULL, NULL,
53 parent: dev);
54 if (ret) {
55 dev_err(dev, "failed to populate child nodes %d\n", ret);
56 goto clk_err;
57 }
58
59 return ret;
60
61clk_err:
62 pm_runtime_put_sync(dev);
63disable_pm:
64 pm_runtime_disable(dev);
65 return ret;
66}
67
68static void ti_j721e_ufs_remove(struct platform_device *pdev)
69{
70 of_platform_depopulate(parent: &pdev->dev);
71 pm_runtime_put_sync(dev: &pdev->dev);
72 pm_runtime_disable(dev: &pdev->dev);
73}
74
75static const struct of_device_id ti_j721e_ufs_of_match[] = {
76 {
77 .compatible = "ti,j721e-ufs",
78 },
79 { },
80};
81
82MODULE_DEVICE_TABLE(of, ti_j721e_ufs_of_match);
83
84static struct platform_driver ti_j721e_ufs_driver = {
85 .probe = ti_j721e_ufs_probe,
86 .remove_new = ti_j721e_ufs_remove,
87 .driver = {
88 .name = "ti-j721e-ufs",
89 .of_match_table = ti_j721e_ufs_of_match,
90 },
91};
92module_platform_driver(ti_j721e_ufs_driver);
93
94MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
95MODULE_DESCRIPTION("TI UFS host controller glue driver");
96MODULE_LICENSE("GPL v2");
97

source code of linux/drivers/ufs/host/ti-j721e-ufs.c