tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2011 Google, Inc.
3 *
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 */
14
15#include <linux/kernel.h>
16#include <linux/usb.h>
17#include <linux/io.h>
18#include <linux/usb/otg.h>
19#include <linux/usb/ulpi.h>
20
21#define ULPI_VIEW_WAKEUP (1 << 31)
22#define ULPI_VIEW_RUN (1 << 30)
23#define ULPI_VIEW_WRITE (1 << 29)
24#define ULPI_VIEW_READ (0 << 29)
25#define ULPI_VIEW_ADDR(x) (((x) & 0xff) << 16)
26#define ULPI_VIEW_DATA_READ(x) (((x) >> 8) & 0xff)
27#define ULPI_VIEW_DATA_WRITE(x) ((x) & 0xff)
28
29static int ulpi_viewport_wait(void __iomem *view, u32 mask)
30{
31 unsigned long usec = 2000;
32
33 while (usec--) {
34 if (!(readl(view) & mask))
35 return 0;
36
37 udelay(1);
38 };
39
40 return -ETIMEDOUT;
41}
42
43static int ulpi_viewport_read(struct usb_phy *otg, u32 reg)
44{
45 int ret;
46 void __iomem *view = otg->io_priv;
47
48 writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
49 ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
50 if (ret)
51 return ret;
52
53 writel(ULPI_VIEW_RUN | ULPI_VIEW_READ | ULPI_VIEW_ADDR(reg), view);
54 ret = ulpi_viewport_wait(view, ULPI_VIEW_RUN);
55 if (ret)
56 return ret;
57
58 return ULPI_VIEW_DATA_READ(readl(view));
59}
60
61static int ulpi_viewport_write(struct usb_phy *otg, u32 val, u32 reg)
62{
63 int ret;
64 void __iomem *view = otg->io_priv;
65
66 writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
67 ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
68 if (ret)
69 return ret;
70
71 writel(ULPI_VIEW_RUN | ULPI_VIEW_WRITE | ULPI_VIEW_DATA_WRITE(val) |
72 ULPI_VIEW_ADDR(reg), view);
73
74 return ulpi_viewport_wait(view, ULPI_VIEW_RUN);
75}
76
77struct usb_phy_io_ops ulpi_viewport_access_ops = {
78 .read = ulpi_viewport_read,
79 .write = ulpi_viewport_write,
80};