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 void 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
 98static const struct of_device_id keystone_usbphy_ids[] = {
 99	{ .compatible = "ti,keystone-usbphy" },
100	{ }
101};
102MODULE_DEVICE_TABLE(of, keystone_usbphy_ids);
103
104static struct platform_driver keystone_usbphy_driver = {
105	.probe          = keystone_usbphy_probe,
106	.remove_new     = keystone_usbphy_remove,
107	.driver         = {
108		.name   = "keystone-usbphy",
109		.of_match_table = keystone_usbphy_ids,
110	},
111};
112
113module_platform_driver(keystone_usbphy_driver);
114
115MODULE_ALIAS("platform:keystone-usbphy");
116MODULE_AUTHOR("Texas Instruments Inc.");
117MODULE_DESCRIPTION("Keystone USB phy driver");
118MODULE_LICENSE("GPL v2");