1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2016 Linaro Ltd.
4 */
5
6#include <linux/device.h>
7#include <linux/usb/chipidea.h>
8#include <linux/ulpi/interface.h>
9
10#include "ci.h"
11
12#define ULPI_WAKEUP		BIT(31)
13#define ULPI_RUN		BIT(30)
14#define ULPI_WRITE		BIT(29)
15#define ULPI_SYNC_STATE		BIT(27)
16#define ULPI_ADDR(n)		((n) << 16)
17#define ULPI_DATA(n)		(n)
18
19static int ci_ulpi_wait(struct ci_hdrc *ci, u32 mask)
20{
21	unsigned long usec = 10000;
22
23	while (usec--) {
24		if (!hw_read(ci, OP_ULPI_VIEWPORT, mask))
25			return 0;
26
27		udelay(1);
28	}
29
30	return -ETIMEDOUT;
31}
32
33static int ci_ulpi_read(struct device *dev, u8 addr)
34{
35	struct ci_hdrc *ci = dev_get_drvdata(dev);
36	int ret;
37
38	hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP);
39	ret = ci_ulpi_wait(ci, ULPI_WAKEUP);
40	if (ret)
41		return ret;
42
43	hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_RUN | ULPI_ADDR(addr));
44	ret = ci_ulpi_wait(ci, ULPI_RUN);
45	if (ret)
46		return ret;
47
48	return hw_read(ci, OP_ULPI_VIEWPORT, GENMASK(15, 8)) >> 8;
49}
50
51static int ci_ulpi_write(struct device *dev, u8 addr, u8 val)
52{
53	struct ci_hdrc *ci = dev_get_drvdata(dev);
54	int ret;
55
56	hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP);
57	ret = ci_ulpi_wait(ci, ULPI_WAKEUP);
58	if (ret)
59		return ret;
60
61	hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff,
62		 ULPI_RUN | ULPI_WRITE | ULPI_ADDR(addr) | val);
63	return ci_ulpi_wait(ci, ULPI_RUN);
64}
65
66int ci_ulpi_init(struct ci_hdrc *ci)
67{
68	if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI)
69		return 0;
70
71	/*
72	 * Set PORTSC correctly so we can read/write ULPI registers for
73	 * identification purposes
74	 */
75	hw_phymode_configure(ci);
76
77	ci->ulpi_ops.read = ci_ulpi_read;
78	ci->ulpi_ops.write = ci_ulpi_write;
79	ci->ulpi = ulpi_register_interface(ci->dev, &ci->ulpi_ops);
80	if (IS_ERR(ci->ulpi))
81		dev_err(ci->dev, "failed to register ULPI interface");
82
83	return PTR_ERR_OR_ZERO(ci->ulpi);
84}
85
86void ci_ulpi_exit(struct ci_hdrc *ci)
87{
88	if (ci->ulpi) {
89		ulpi_unregister_interface(ci->ulpi);
90		ci->ulpi = NULL;
91	}
92}
93
94int ci_ulpi_resume(struct ci_hdrc *ci)
95{
96	int cnt = 100000;
97
98	if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI)
99		return 0;
100
101	while (cnt-- > 0) {
102		if (hw_read(ci, OP_ULPI_VIEWPORT, ULPI_SYNC_STATE))
103			return 0;
104		udelay(1);
105	}
106
107	return -ETIMEDOUT;
108}
109