diff options
Diffstat (limited to 'drivers/usb/otg/ulpi_viewport.c')
-rw-r--r-- | drivers/usb/otg/ulpi_viewport.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/usb/otg/ulpi_viewport.c b/drivers/usb/otg/ulpi_viewport.c new file mode 100644 index 000000000000..e9a37f90994f --- /dev/null +++ b/drivers/usb/otg/ulpi_viewport.c | |||
@@ -0,0 +1,80 @@ | |||
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 | |||
29 | static 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 | |||
43 | static int ulpi_viewport_read(struct otg_transceiver *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 | |||
61 | static int ulpi_viewport_write(struct otg_transceiver *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 | |||
77 | struct otg_io_access_ops ulpi_viewport_access_ops = { | ||
78 | .read = ulpi_viewport_read, | ||
79 | .write = ulpi_viewport_write, | ||
80 | }; | ||