drivers/usb/musb/am35x.c

   1 /*
   2  * am35x.c - TI's AM35x platform specific usb wrapper functions.
   3  *
   4  * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
   5  *
   6  * Based on drivers/usb/musb/da8xx.c
   7  *
   8  * Copyright (c) 2010 Texas Instruments Incorporated
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24 #include <common.h>
  25
  26 #include "am35x.h"
  27
  28 /* MUSB platform configuration */
  29 struct musb_config musb_cfg = {
  30         .regs           = (struct musb_regs *)AM35X_USB_OTG_CORE_BASE,
  31         .timeout        = AM35X_USB_OTG_TIMEOUT,
  32         .musb_speed     = 0,
  33 };
  34
  35 /*
  36  * Enable the USB phy
  37  */
  38 static u8 phy_on(void)
  39 {
  40         u32 devconf2;
  41         u32 timeout;
  42
  43         devconf2 = readl(&am35x_scm_general_regs->devconf2);
  44
  45         devconf2 &= ~(DEVCONF2_RESET | DEVCONF2_PHYPWRDN | DEVCONF2_OTGPWRDN |
  46                       DEVCONF2_OTGMODE | DEVCONF2_REFFREQ |
  47                       DEVCONF2_PHY_GPIOMODE);
  48         devconf2 |= DEVCONF2_SESENDEN | DEVCONF2_VBDTCTEN | DEVCONF2_PHY_PLLON |
  49                     DEVCONF2_REFFREQ_13MHZ | DEVCONF2_DATPOL;
  50
  51         writel(devconf2, &am35x_scm_general_regs->devconf2);
  52
  53         /* wait until the USB phy is turned on */
  54         timeout = musb_cfg.timeout;
  55         while (timeout--)
  56                 if (readl(&am35x_scm_general_regs->devconf2) & DEVCONF2_PHYCKGD)
  57                         return 1;
  58
  59         /* USB phy was not turned on */
  60         return 0;
  61 }
  62
  63 /*
  64  * Disable the USB phy
  65  */
  66 static void phy_off(void)
  67 {
  68         u32 devconf2;
  69
  70         /*
  71          * Power down the on-chip PHY.
  72          */
  73         devconf2 = readl(&am35x_scm_general_regs->devconf2);
  74
  75         devconf2 &= ~DEVCONF2_PHY_PLLON;
  76         devconf2 |= DEVCONF2_PHYPWRDN | DEVCONF2_OTGPWRDN;
  77         writel(devconf2, &am35x_scm_general_regs->devconf2);
  78 }
  79
  80 /*
  81  * This function performs platform specific initialization for usb0.
  82  */
  83 int musb_platform_init(void)
  84 {
  85         u32 revision;
  86         u32 sw_reset;
  87
  88         /* global usb reset */
  89         sw_reset = readl(&am35x_scm_general_regs->ip_sw_reset);
  90         sw_reset |= (1 << 0);
  91         writel(sw_reset, &am35x_scm_general_regs->ip_sw_reset);
  92         sw_reset &= ~(1 << 0);
  93         writel(sw_reset, &am35x_scm_general_regs->ip_sw_reset);
  94
  95         /* reset the controller */
  96         writel(0x1, &am35x_usb_regs->control);
  97         udelay(5000);
  98
  99         /* start the on-chip usb phy and its pll */
 100         if (phy_on() == 0)
 101                 return -1;
 102
 103         /* Returns zero if e.g. not clocked */
 104         revision = readl(&am35x_usb_regs->revision);
 105         if (revision == 0)
 106                 return -1;
 107
 108         return 0;
 109 }
 110
 111 /*
 112  * This function performs platform specific deinitialization for usb0.
 113  */
 114 void musb_platform_deinit(void)
 115 {
 116         /* Turn off the phy */
 117         phy_off();
 118 }
 119
 120 /*
 121  * This function reads data from endpoint fifo for AM35x
 122  * which supports only 32bit read operation.
 123  *
 124  * ep           - endpoint number
 125  * length       - number of bytes to read from FIFO
 126  * fifo_data    - pointer to data buffer into which data is read
 127  */
 128 __attribute__((weak))
 129 void read_fifo(u8 ep, u32 length, void *fifo_data)
 130 {
 131         u8  *data = (u8 *)fifo_data;
 132         u32 val;
 133         int i;
 134
 135         /* select the endpoint index */
 136         writeb(ep, &musbr->index);
 137
 138         if (length > 4) {
 139                 for (i = 0; i < (length >> 2); i++) {
 140                         val = readl(&musbr->fifox[ep]);
 141                         memcpy(data, &val, 4);
 142                         data += 4;
 143                 }
 144                 length %= 4;
 145         }
 146         if (length > 0) {
 147                 val = readl(&musbr->fifox[ep]);
 148                 memcpy(data, &val, length);
 149         }
 150 }