tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Generic ULPI USB transceiver support
3 *
4 * Copyright (C) 2009 Daniel Mack <daniel@caiaq.de>
5 *
6 * Based on sources from
7 *
8 * Sascha Hauer <s.hauer@pengutronix.de>
9 * Freescale Semiconductors
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26#include <linux/kernel.h>
27#include <linux/usb.h>
28#include <linux/usb/otg.h>
29#include <linux/usb/ulpi.h>
30
31/* ULPI register addresses */
32#define ULPI_VID_LOW 0x00 /* Vendor ID low */
33#define ULPI_VID_HIGH 0x01 /* Vendor ID high */
34#define ULPI_PID_LOW 0x02 /* Product ID low */
35#define ULPI_PID_HIGH 0x03 /* Product ID high */
36#define ULPI_ITFCTL 0x07 /* Interface Control */
37#define ULPI_OTGCTL 0x0A /* OTG Control */
38
39/* add to above register address to access Set/Clear functions */
40#define ULPI_REG_SET 0x01
41#define ULPI_REG_CLEAR 0x02
42
43/* ULPI OTG Control Register bits */
44#define ID_PULL_UP (1 << 0) /* enable ID Pull Up */
45#define DP_PULL_DOWN (1 << 1) /* enable DP Pull Down */
46#define DM_PULL_DOWN (1 << 2) /* enable DM Pull Down */
47#define DISCHRG_VBUS (1 << 3) /* Discharge Vbus */
48#define CHRG_VBUS (1 << 4) /* Charge Vbus */
49#define DRV_VBUS (1 << 5) /* Drive Vbus */
50#define DRV_VBUS_EXT (1 << 6) /* Drive Vbus external */
51#define USE_EXT_VBUS_IND (1 << 7) /* Use ext. Vbus indicator */
52
53#define ULPI_ID(vendor, product) (((vendor) << 16) | (product))
54
55#define TR_FLAG(flags, a, b) (((flags) & a) ? b : 0)
56
57/* ULPI hardcoded IDs, used for probing */
58static unsigned int ulpi_ids[] = {
59 ULPI_ID(0x04cc, 0x1504), /* NXP ISP1504 */
60};
61
62static int ulpi_set_flags(struct otg_transceiver *otg)
63{
64 unsigned int flags = 0;
65
66 if (otg->flags & USB_OTG_PULLUP_ID)
67 flags |= ID_PULL_UP;
68
69 if (otg->flags & USB_OTG_PULLDOWN_DM)
70 flags |= DM_PULL_DOWN;
71
72 if (otg->flags & USB_OTG_PULLDOWN_DP)
73 flags |= DP_PULL_DOWN;
74
75 if (otg->flags & USB_OTG_EXT_VBUS_INDICATOR)
76 flags |= USE_EXT_VBUS_IND;
77
78 return otg_io_write(otg, flags, ULPI_OTGCTL + ULPI_REG_SET);
79}
80
81static int ulpi_init(struct otg_transceiver *otg)
82{
83 int i, vid, pid;
84
85 vid = (otg_io_read(otg, ULPI_VID_HIGH) << 8) |
86 otg_io_read(otg, ULPI_VID_LOW);
87 pid = (otg_io_read(otg, ULPI_PID_HIGH) << 8) |
88 otg_io_read(otg, ULPI_PID_LOW);
89
90 pr_info("ULPI transceiver vendor/product ID 0x%04x/0x%04x\n", vid, pid);
91
92 for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++)
93 if (ulpi_ids[i] == ULPI_ID(vid, pid))
94 return ulpi_set_flags(otg);
95
96 pr_err("ULPI ID does not match any known transceiver.\n");
97 return -ENODEV;
98}
99
100static int ulpi_set_vbus(struct otg_transceiver *otg, bool on)
101{
102 unsigned int flags = otg_io_read(otg, ULPI_OTGCTL);
103
104 flags &= ~(DRV_VBUS | DRV_VBUS_EXT);
105
106 if (on) {
107 if (otg->flags & USB_OTG_DRV_VBUS)
108 flags |= DRV_VBUS;
109
110 if (otg->flags & USB_OTG_DRV_VBUS_EXT)
111 flags |= DRV_VBUS_EXT;
112 }
113
114 return otg_io_write(otg, flags, ULPI_OTGCTL + ULPI_REG_SET);
115}
116
117struct otg_transceiver *
118otg_ulpi_create(struct otg_io_access_ops *ops,
119 unsigned int flags)
120{
121 struct otg_transceiver *otg;
122
123 otg = kzalloc(sizeof(*otg), GFP_KERNEL);
124 if (!otg)
125 return NULL;
126
127 otg->label = "ULPI";
128 otg->flags = flags;
129 otg->io_ops = ops;
130 otg->init = ulpi_init;
131 otg->set_vbus = ulpi_set_vbus;
132
133 return otg;
134}
135EXPORT_SYMBOL_GPL(otg_ulpi_create);
136