drivers/usb/musb/da8xx.c

   1 /*
   2  * da8xx.c - TI's DA8xx platform specific usb wrapper functions.
   3  *
   4  * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
   5  *
   6  * Based on drivers/usb/musb/davinci.c
   7  *
   8  * Copyright (C) 2009 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 "musb_core.h"
  27 #include <asm/arch/da8xx-usb.h>
  28
  29 /* MUSB platform configuration */
  30 struct musb_config musb_cfg = {
  31         .regs           = (struct musb_regs *)DA8XX_USB_OTG_CORE_BASE,
  32         .timeout        = DA8XX_USB_OTG_TIMEOUT,
  33         .musb_speed     = 0,
  34 };
  35
  36 /*
  37  * This function enables VBUS by driving the GPIO Bank4 Pin 15 high.
  38  */
  39 static void enable_vbus(void)
  40 {
  41         u32 value;
  42
  43         /* configure GPIO bank4 pin 15 in output direction */
  44         value = readl(&davinci_gpio_bank45->dir);
  45         writel((value & (~DA8XX_USB_VBUS_GPIO)), &davinci_gpio_bank45->dir);
  46
  47         /* set GPIO bank4 pin 15 high to drive VBUS */
  48         value = readl(&davinci_gpio_bank45->set_data);
  49         writel((value | DA8XX_USB_VBUS_GPIO), &davinci_gpio_bank45->set_data);
  50 }
  51
  52 /*
  53  * Enable the usb0 phy. This initialization procedure is explained in
  54  * the DA8xx USB user guide document.
  55  */
  56 static u8 phy_on(void)
  57 {
  58         u32 timeout;
  59         u32 cfgchip2;
  60
  61         cfgchip2 = readl(&davinci_syscfg_regs->cfgchip2);
  62
  63         cfgchip2 &= ~(CFGCHIP2_RESET | CFGCHIP2_PHYPWRDN | CFGCHIP2_OTGPWRDN |
  64                       CFGCHIP2_OTGMODE | CFGCHIP2_REFFREQ);
  65         cfgchip2 |= CFGCHIP2_SESENDEN | CFGCHIP2_VBDTCTEN | CFGCHIP2_PHY_PLLON |
  66                     CFGCHIP2_REFFREQ_24MHZ;
  67
  68         writel(cfgchip2, &davinci_syscfg_regs->cfgchip2);
  69
  70         /* wait until the usb phy pll locks */
  71         timeout = musb_cfg.timeout;
  72         while (timeout--)
  73                 if (readl(&davinci_syscfg_regs->cfgchip2) & CFGCHIP2_PHYCLKGD)
  74                         return 1;
  75
  76         /* USB phy was not turned on */
  77         return 0;
  78 }
  79
  80 /*
  81  * Disable the usb phy
  82  */
  83 static void phy_off(void)
  84 {
  85         u32 cfgchip2;
  86
  87         /*
  88          * Power down the on-chip PHY.
  89          */
  90         cfgchip2 = readl(&davinci_syscfg_regs->cfgchip2);
  91         cfgchip2 &= ~CFGCHIP2_PHY_PLLON;
  92         cfgchip2 |= CFGCHIP2_PHYPWRDN | CFGCHIP2_OTGPWRDN;
  93         writel(cfgchip2, &davinci_syscfg_regs->cfgchip2);
  94 }
  95
  96 /*
  97  * This function performs DA8xx platform specific initialization for usb0.
  98  */
  99 int musb_platform_init(void)
 100 {
 101         u32  revision;
 102
 103         /* enable psc for usb2.0 */
 104         lpsc_on(33);
 105
 106         /* enable usb vbus */
 107         enable_vbus();
 108
 109         /* reset the controller */
 110         writel(0x1, &da8xx_usb_regs->control);
 111         udelay(5000);
 112
 113         /* start the on-chip usb phy and its pll */
 114         if (phy_on() == 0)
 115                 return -1;
 116
 117         /* Returns zero if e.g. not clocked */
 118         revision = readl(&da8xx_usb_regs->revision);
 119         if (revision == 0)
 120                 return -1;
 121
 122         /* Disable all interrupts */
 123         writel((DA8XX_USB_USBINT_MASK | DA8XX_USB_TXINT_MASK |
 124                 DA8XX_USB_RXINT_MASK), &da8xx_usb_regs->intmsk_set);
 125         return 0;
 126 }
 127
 128 /*
 129  * This function performs DA8xx platform specific deinitialization for usb0.
 130  */
 131 void musb_platform_deinit(void)
 132 {
 133         /* Turn of the phy */
 134         phy_off();
 135
 136         /* flush any interrupts */
 137         writel((DA8XX_USB_USBINT_MASK | DA8XX_USB_TXINT_MASK |
 138                 DA8XX_USB_RXINT_MASK), &da8xx_usb_regs->intmsk_clr);
 139         writel(0, &da8xx_usb_regs->eoi);
 140 }