1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Renesas USB driver R-Car Gen. 3 initialization and power control
  4 *
  5 * Copyright (C) 2016 Renesas Electronics Corporation
  6 */
  7
  8#include <linux/delay.h>
  9#include <linux/io.h>
 10#include "common.h"
 11#include "rcar3.h"
 12
 13#define LPSTS		0x102
 14#define UGCTRL		0x180	/* 32-bit register */
 15#define UGCTRL2		0x184	/* 32-bit register */
 16#define UGSTS		0x188	/* 32-bit register */
 17
 18/* Low Power Status register (LPSTS) */
 19#define LPSTS_SUSPM	0x4000
 20
 21/* R-Car D3 only: USB General control register (UGCTRL) */
 22#define UGCTRL_PLLRESET		0x00000001
 23#define UGCTRL_CONNECT		0x00000004
 24
 25/*
 26 * USB General control register 2 (UGCTRL2)
 27 * Remarks: bit[31:11] and bit[9:6] should be 0
 28 */
 29#define UGCTRL2_RESERVED_3	0x00000001	/* bit[3:0] should be B'0001 */
 30#define UGCTRL2_USB0SEL_EHCI	0x00000010
 31#define UGCTRL2_USB0SEL_HSUSB	0x00000020
 32#define UGCTRL2_USB0SEL_OTG	0x00000030
 33#define UGCTRL2_VBUSSEL		0x00000400
 34
 35/* R-Car D3 only: USB General status register (UGSTS) */
 36#define UGSTS_LOCK		0x00000100
 37
 38static void usbhs_write32(struct usbhs_priv *priv, u32 reg, u32 data)
 39{
 40	iowrite32(data, priv->base + reg);
 41}
 42
 43static u32 usbhs_read32(struct usbhs_priv *priv, u32 reg)
 44{
 45	return ioread32(priv->base + reg);
 46}
 47
 48static void usbhs_rcar3_set_ugctrl2(struct usbhs_priv *priv, u32 val)
 49{
 50	usbhs_write32(priv, UGCTRL2, val | UGCTRL2_RESERVED_3);
 51}
 52
 53static void usbhs_rcar3_set_usbsel(struct usbhs_priv *priv, bool ehci)
 54{
 55	if (ehci)
 56		usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_EHCI);
 57	else
 58		usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_HSUSB);
 59}
 60
 61static int usbhs_rcar3_power_ctrl(struct platform_device *pdev,
 62				void __iomem *base, int enable)
 63{
 64	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
 65
 66	usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_OTG | UGCTRL2_VBUSSEL);
 67
 68	if (enable) {
 69		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
 70		/* The controller on R-Car Gen3 needs to wait up to 45 usec */
 71		udelay(45);
 72	} else {
 73		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
 74	}
 75
 76	return 0;
 77}
 78
 79/* R-Car D3 needs to release UGCTRL.PLLRESET */
 80static int usbhs_rcar3_power_and_pll_ctrl(struct platform_device *pdev,
 81					  void __iomem *base, int enable)
 82{
 83	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
 84	u32 val;
 85	int timeout = 1000;
 86	bool is_host = false;
 87
 88	if (enable) {
 89		usbhs_write32(priv, UGCTRL, 0);	/* release PLLRESET */
 90		if (priv->edev)
 91			is_host = extcon_get_state(priv->edev, EXTCON_USB_HOST);
 92
 93		usbhs_rcar3_set_usbsel(priv, is_host);
 94
 95		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
 96		do {
 97			val = usbhs_read32(priv, UGSTS);
 98			udelay(1);
 99		} while (!(val & UGSTS_LOCK) && timeout--);
100		usbhs_write32(priv, UGCTRL, UGCTRL_CONNECT);
101	} else {
102		usbhs_write32(priv, UGCTRL, 0);
103		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
104		usbhs_write32(priv, UGCTRL, UGCTRL_PLLRESET);
105	}
106
107	return 0;
108}
109
110static int usbhs_rcar3_get_id(struct platform_device *pdev)
111{
112	return USBHS_GADGET;
113}
114
115static int usbhs_rcar3_notifier(struct notifier_block *nb, unsigned long event,
116				void *data)
117{
118	struct usbhs_priv *priv = container_of(nb, struct usbhs_priv, nb);
119
120	usbhs_rcar3_set_usbsel(priv, !!event);
121
122	return NOTIFY_DONE;
123}
124
125const struct renesas_usbhs_platform_callback usbhs_rcar3_ops = {
126	.power_ctrl = usbhs_rcar3_power_ctrl,
127	.get_id = usbhs_rcar3_get_id,
128};
129
130const struct renesas_usbhs_platform_callback usbhs_rcar3_with_pll_ops = {
131	.power_ctrl = usbhs_rcar3_power_and_pll_ctrl,
132	.get_id = usbhs_rcar3_get_id,
133	.notifier = usbhs_rcar3_notifier,
134};