LXR linux/drivers/usb/phy/phy-keystone.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * phy-keystone - USB PHY, talking to dwc3 controller in Keystone.
   4 *
   5 * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com
   6 *
   7 * Author: WingMan Kwok <w-kwok2@ti.com>
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/platform_device.h>
  12#include <linux/usb/usb_phy_generic.h>
  13#include <linux/io.h>
  14#include <linux/of.h>
  15
  16#include "phy-generic.h"
  17
  18/* USB PHY control register offsets */
  19#define USB_PHY_CTL_UTMI                0x0000
  20#define USB_PHY_CTL_PIPE                0x0004
  21#define USB_PHY_CTL_PARAM_1             0x0008
  22#define USB_PHY_CTL_PARAM_2             0x000c
  23#define USB_PHY_CTL_CLOCK               0x0010
  24#define USB_PHY_CTL_PLL                 0x0014
  25
  26#define PHY_REF_SSP_EN                  BIT(29)
  27
  28struct keystone_usbphy {
  29        struct usb_phy_generic  usb_phy_gen;
  30        void __iomem                    *phy_ctrl;
  31};
  32
  33static inline u32 keystone_usbphy_readl(void __iomem *base, u32 offset)
  34{
  35        return readl(base + offset);
  36}
  37
  38static inline void keystone_usbphy_writel(void __iomem *base,
  39                                          u32 offset, u32 value)
  40{
  41        writel(value, base + offset);
  42}
  43
  44static int keystone_usbphy_init(struct usb_phy *phy)
  45{
  46        struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev);
  47        u32 val;
  48
  49        val  = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK);
  50        keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK,
  51                                val | PHY_REF_SSP_EN);
  52        return 0;
  53}
  54
  55static void keystone_usbphy_shutdown(struct usb_phy *phy)
  56{
  57        struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev);
  58        u32 val;
  59
  60        val  = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK);
  61        keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK,
  62                                val &= ~PHY_REF_SSP_EN);
  63}
  64
  65static int keystone_usbphy_probe(struct platform_device *pdev)
  66{
  67        struct device           *dev = &pdev->dev;
  68        struct keystone_usbphy  *k_phy;
  69        int ret;
  70
  71        k_phy = devm_kzalloc(dev, sizeof(*k_phy), GFP_KERNEL);
  72        if (!k_phy)
  73                return -ENOMEM;
  74
  75        k_phy->phy_ctrl = devm_platform_ioremap_resource(pdev, 0);
  76        if (IS_ERR(k_phy->phy_ctrl))
  77                return PTR_ERR(k_phy->phy_ctrl);
  78
  79        ret = usb_phy_gen_create_phy(dev, &k_phy->usb_phy_gen);
  80        if (ret)
  81                return ret;
  82
  83        k_phy->usb_phy_gen.phy.init = keystone_usbphy_init;
  84        k_phy->usb_phy_gen.phy.shutdown = keystone_usbphy_shutdown;
  85
  86        platform_set_drvdata(pdev, k_phy);
  87
  88        return usb_add_phy_dev(&k_phy->usb_phy_gen.phy);
  89}
  90
  91static int keystone_usbphy_remove(struct platform_device *pdev)
  92{
  93        struct keystone_usbphy *k_phy = platform_get_drvdata(pdev);
  94
  95        usb_remove_phy(&k_phy->usb_phy_gen.phy);
  96
  97        return 0;
  98}
  99
 100static const struct of_device_id keystone_usbphy_ids[] = {
 101        { .compatible = "ti,keystone-usbphy" },
 102        { }
 103};
 104MODULE_DEVICE_TABLE(of, keystone_usbphy_ids);
 105
 106static struct platform_driver keystone_usbphy_driver = {
 107        .probe          = keystone_usbphy_probe,
 108        .remove         = keystone_usbphy_remove,
 109        .driver         = {
 110                .name   = "keystone-usbphy",
 111                .of_match_table = keystone_usbphy_ids,
 112        },
 113};
 114
 115module_platform_driver(keystone_usbphy_driver);
 116
 117MODULE_ALIAS("platform:keystone-usbphy");
 118MODULE_AUTHOR("Texas Instruments Inc.");
 119MODULE_DESCRIPTION("Keystone USB phy driver");
 120MODULE_LICENSE("GPL v2");
 121