drivers/usb/otg/ulpi.c

   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/slab.h>
  28 #include <linux/usb.h>
  29 #include <linux/usb/otg.h>
  30 #include <linux/usb/ulpi.h>
  31
  32 #define ULPI_ID(vendor, product) (((vendor) << 16) | (product))
  33
  34 #define TR_FLAG(flags, a, b)    (((flags) & a) ? b : 0)
  35
  36 /* ULPI hardcoded IDs, used for probing */
  37 static unsigned int ulpi_ids[] = {
  38         ULPI_ID(0x04cc, 0x1504),        /* NXP ISP1504 */
  39 };
  40
  41 static int ulpi_set_flags(struct otg_transceiver *otg)
  42 {
  43         unsigned int flags = 0;
  44
  45         if (otg->flags & USB_OTG_PULLUP_ID)
  46                 flags |= ULPI_OTG_CTRL_ID_PULLUP;
  47
  48         if (otg->flags & USB_OTG_PULLDOWN_DM)
  49                 flags |= ULPI_OTG_CTRL_DM_PULLDOWN;
  50
  51         if (otg->flags & USB_OTG_PULLDOWN_DP)
  52                 flags |= ULPI_OTG_CTRL_DP_PULLDOWN;
  53
  54         if (otg->flags & USB_OTG_EXT_VBUS_INDICATOR)
  55                 flags |= ULPI_OTG_CTRL_EXTVBUSIND;
  56
  57         return otg_io_write(otg, flags, ULPI_OTG_CTRL);
  58 }
  59
  60 static int ulpi_init(struct otg_transceiver *otg)
  61 {
  62         int i, vid, pid, ret;
  63         u32 ulpi_id = 0;
  64
  65         for (i = 0; i < 4; i++) {
  66                 ret = otg_io_read(otg, ULPI_PRODUCT_ID_HIGH - i);
  67                 if (ret < 0)
  68                         return ret;
  69                 ulpi_id = (ulpi_id << 8) | ret;
  70         }
  71         vid = ulpi_id & 0xffff;
  72         pid = ulpi_id >> 16;
  73
  74         pr_info("ULPI transceiver vendor/product ID 0x%04x/0x%04x\n", vid, pid);
  75
  76         for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++)
  77                 if (ulpi_ids[i] == ULPI_ID(vid, pid))
  78                         return ulpi_set_flags(otg);
  79
  80         pr_err("ULPI ID does not match any known transceiver.\n");
  81         return -ENODEV;
  82 }
  83
  84 static int ulpi_set_vbus(struct otg_transceiver *otg, bool on)
  85 {
  86         unsigned int flags = otg_io_read(otg, ULPI_OTG_CTRL);
  87
  88         flags &= ~(ULPI_OTG_CTRL_DRVVBUS | ULPI_OTG_CTRL_DRVVBUS_EXT);
  89
  90         if (on) {
  91                 if (otg->flags & USB_OTG_DRV_VBUS)
  92                         flags |= ULPI_OTG_CTRL_DRVVBUS;
  93
  94                 if (otg->flags & USB_OTG_DRV_VBUS_EXT)
  95                         flags |= ULPI_OTG_CTRL_DRVVBUS_EXT;
  96         }
  97
  98         return otg_io_write(otg, flags, ULPI_OTG_CTRL);
  99 }
 100
 101 struct otg_transceiver *
 102 otg_ulpi_create(struct otg_io_access_ops *ops,
 103                 unsigned int flags)
 104 {
 105         struct otg_transceiver *otg;
 106
 107         otg = kzalloc(sizeof(*otg), GFP_KERNEL);
 108         if (!otg)
 109                 return NULL;
 110
 111         otg->label      = "ULPI";
 112         otg->flags      = flags;
 113         otg->io_ops     = ops;
 114         otg->init       = ulpi_init;
 115         otg->set_vbus   = ulpi_set_vbus;
 116
 117         return otg;
 118 }
 119 EXPORT_SYMBOL_GPL(otg_ulpi_create);
 120