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_HSUSB	0x00000020
31 #define UGCTRL2_USB0SEL_OTG	0x00000030
32 #define UGCTRL2_VBUSSEL		0x00000400
33 
34 /* R-Car D3 only: USB General status register (UGSTS) */
35 #define UGSTS_LOCK		0x00000100
36 
37 static void usbhs_write32(struct usbhs_priv *priv, u32 reg, u32 data)
38 {
39 	iowrite32(data, priv->base + reg);
40 }
41 
42 static u32 usbhs_read32(struct usbhs_priv *priv, u32 reg)
43 {
44 	return ioread32(priv->base + reg);
45 }
46 
47 static int usbhs_rcar3_power_ctrl(struct platform_device *pdev,
48 				void __iomem *base, int enable)
49 {
50 	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
51 
52 	usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 | UGCTRL2_USB0SEL_OTG |
53 		      UGCTRL2_VBUSSEL);
54 
55 	if (enable) {
56 		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
57 		/* The controller on R-Car Gen3 needs to wait up to 45 usec */
58 		udelay(45);
59 	} else {
60 		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
61 	}
62 
63 	return 0;
64 }
65 
66 /* R-Car D3 needs to release UGCTRL.PLLRESET */
67 static int usbhs_rcar3_power_and_pll_ctrl(struct platform_device *pdev,
68 					  void __iomem *base, int enable)
69 {
70 	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
71 	u32 val;
72 	int timeout = 1000;
73 
74 	if (enable) {
75 		usbhs_write32(priv, UGCTRL, 0);	/* release PLLRESET */
76 		usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 |
77 			      UGCTRL2_USB0SEL_HSUSB);
78 
79 		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
80 		do {
81 			val = usbhs_read32(priv, UGSTS);
82 			udelay(1);
83 		} while (!(val & UGSTS_LOCK) && timeout--);
84 		usbhs_write32(priv, UGCTRL, UGCTRL_CONNECT);
85 	} else {
86 		usbhs_write32(priv, UGCTRL, 0);
87 		usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
88 		usbhs_write32(priv, UGCTRL, UGCTRL_PLLRESET);
89 	}
90 
91 	return 0;
92 }
93 
94 static int usbhs_rcar3_get_id(struct platform_device *pdev)
95 {
96 	return USBHS_GADGET;
97 }
98 
99 const struct renesas_usbhs_platform_callback usbhs_rcar3_ops = {
100 	.power_ctrl = usbhs_rcar3_power_ctrl,
101 	.get_id = usbhs_rcar3_get_id,
102 };
103 
104 const struct renesas_usbhs_platform_callback usbhs_rcar3_with_pll_ops = {
105 	.power_ctrl = usbhs_rcar3_power_and_pll_ctrl,
106 	.get_id = usbhs_rcar3_get_id,
107 };
108