Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * ulpi.c - DesignWare USB3 Controller's ULPI PHY interface
4 *
5 * Copyright (C) 2015 Intel Corporation
6 *
7 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
8 */
9
10#include <linux/delay.h>
11#include <linux/time64.h>
12#include <linux/ulpi/regs.h>
13#include <linux/ulpi/driver.h>
14
15#include "core.h"
16#include "io.h"
17
18#define USB_VENDOR_MICROCHIP 0x0424
19
20#define DWC3_ULPI_ADDR(a) \
21 ((a >= ULPI_EXT_VENDOR_SPECIFIC) ? \
22 DWC3_GUSB2PHYACC_ADDR(ULPI_ACCESS_EXTENDED) | \
23 DWC3_GUSB2PHYACC_EXTEND_ADDR(a) : DWC3_GUSB2PHYACC_ADDR(a))
24
25#define DWC3_ULPI_BASE_DELAY DIV_ROUND_UP(NSEC_PER_SEC, 60000000L)
26
27static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read)
28{
29 unsigned long ns = 5L * DWC3_ULPI_BASE_DELAY;
30 unsigned int count = 10000;
31 u32 reg;
32
33 if (addr >= ULPI_EXT_VENDOR_SPECIFIC)
34 ns += DWC3_ULPI_BASE_DELAY;
35
36 if (read)
37 ns += DWC3_ULPI_BASE_DELAY;
38
39 reg = dwc3_readl(dwc, DWC3_GUSB2PHYCFG(0));
40 if (reg & DWC3_GUSB2PHYCFG_SUSPHY)
41 usleep_range(1000, 1200);
42
43 while (count--) {
44 ndelay(ns);
45 reg = dwc3_readl(dwc, DWC3_GUSB2PHYACC(0));
46 if (reg & DWC3_GUSB2PHYACC_DONE)
47 return 0;
48 cpu_relax();
49 }
50
51 return -ETIMEDOUT;
52}
53
54static int dwc3_ulpi_read(struct device *dev, u8 addr)
55{
56 struct dwc3 *dwc = dev_get_drvdata(dev);
57 u32 reg;
58 int ret;
59
60 reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr);
61 dwc3_writel(dwc, DWC3_GUSB2PHYACC(0), reg);
62
63 ret = dwc3_ulpi_busyloop(dwc, addr, true);
64 if (ret)
65 return ret;
66
67 reg = dwc3_readl(dwc, DWC3_GUSB2PHYACC(0));
68
69 return DWC3_GUSB2PHYACC_DATA(reg);
70}
71
72static int dwc3_ulpi_write(struct device *dev, u8 addr, u8 val)
73{
74 struct dwc3 *dwc = dev_get_drvdata(dev);
75 u32 reg;
76
77 reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr);
78 reg |= DWC3_GUSB2PHYACC_WRITE | val;
79 dwc3_writel(dwc, DWC3_GUSB2PHYACC(0), reg);
80
81 return dwc3_ulpi_busyloop(dwc, addr, false);
82}
83
84static const struct ulpi_ops dwc3_ulpi_ops = {
85 .read = dwc3_ulpi_read,
86 .write = dwc3_ulpi_write,
87};
88
89static void dwc3_ulpi_detect_config(struct dwc3 *dwc)
90{
91 struct ulpi *ulpi = dwc->ulpi;
92
93 switch (ulpi->id.vendor) {
94 case USB_VENDOR_MICROCHIP:
95 switch (ulpi->id.product) {
96 case 0x0009:
97 /* Microchip USB3340 ULPI PHY */
98 dwc->enable_usb2_transceiver_delay = true;
99 break;
100 default:
101 break;
102 }
103 break;
104 default:
105 break;
106 }
107}
108
109int dwc3_ulpi_init(struct dwc3 *dwc)
110{
111 /* Register the interface */
112 dwc->ulpi = ulpi_register_interface(dwc->dev, &dwc3_ulpi_ops);
113 if (IS_ERR(dwc->ulpi)) {
114 dev_err(dwc->dev, "failed to register ULPI interface");
115 return PTR_ERR(dwc->ulpi);
116 }
117
118 dwc3_ulpi_detect_config(dwc);
119
120 return 0;
121}
122
123void dwc3_ulpi_exit(struct dwc3 *dwc)
124{
125 if (dwc->ulpi) {
126 ulpi_unregister_interface(dwc->ulpi);
127 dwc->ulpi = NULL;
128 }
129}