drivers/usb/ulpi/omap-ulpi-viewport.c

   1 /*
   2  * OMAP ulpi viewport support
   3  * Based on drivers/usb/ulpi/ulpi-viewport.c
   4  *
   5  * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com
   6  * Author: Govindraj R <govindraj.raja@ti.com>
   7  *
   8  * This program is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2  of
  10  * the License as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <common.h>
  22 #include <asm/io.h>
  23 #include <usb/ulpi.h>
  24
  25 #define OMAP_ULPI_WR_OPSEL      (2 << 22)
  26 #define OMAP_ULPI_RD_OPSEL      (3 << 22)
  27 #define OMAP_ULPI_START         (1 << 31)
  28
  29 /*
  30  * Wait for having ulpi in done state
  31  */
  32 static int ulpi_wait(struct ulpi_viewport *ulpi_vp, u32 mask)
  33 {
  34         int timeout = CONFIG_USB_ULPI_TIMEOUT;
  35
  36         while (--timeout) {
  37                 if (!(readl(ulpi_vp->viewport_addr) & mask))
  38                         return 0;
  39
  40                 udelay(1);
  41         }
  42
  43         return ULPI_ERROR;
  44 }
  45
  46 /*
  47  * Issue a ULPI read/write request
  48  */
  49 static int ulpi_request(struct ulpi_viewport *ulpi_vp, u32 value)
  50 {
  51         int err;
  52
  53         writel(value, ulpi_vp->viewport_addr);
  54
  55         err = ulpi_wait(ulpi_vp, OMAP_ULPI_START);
  56         if (err)
  57                 debug("ULPI request timed out\n");
  58
  59         return err;
  60 }
  61
  62 int ulpi_write(struct ulpi_viewport *ulpi_vp, u8 *reg, u32 value)
  63 {
  64         u32 val = OMAP_ULPI_START | (((ulpi_vp->port_num + 1) & 0xf) << 24) |
  65                         OMAP_ULPI_WR_OPSEL | ((u32)reg << 16) | (value & 0xff);
  66
  67         return ulpi_request(ulpi_vp, val);
  68 }
  69
  70 u32 ulpi_read(struct ulpi_viewport *ulpi_vp, u8 *reg)
  71 {
  72         int err;
  73         u32 val = OMAP_ULPI_START | (((ulpi_vp->port_num + 1) & 0xf) << 24) |
  74                          OMAP_ULPI_RD_OPSEL | ((u32)reg << 16);
  75
  76         err = ulpi_request(ulpi_vp, val);
  77         if (err)
  78                 return err;
  79
  80         return readl(ulpi_vp->viewport_addr) & 0xff;
  81 }