arch/arm/mach-s3c64xx/setup-usb-phy.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright (C) 2011 Samsung Electronics Co.Ltd
   4 // Author: Joonyoung Shim <jy0922.shim@samsung.com>
   5
   6 #include <linux/clk.h>
   7 #include <linux/delay.h>
   8 #include <linux/err.h>
   9 #include <linux/io.h>
  10 #include <linux/platform_device.h>
  11 #include <mach/map.h>
  12 #include <plat/cpu.h>
  13 #include <plat/usb-phy.h>
  14
  15 #include "regs-sys.h"
  16 #include "regs-usb-hsotg-phy.h"
  17
  18 enum samsung_usb_phy_type {
  19         USB_PHY_TYPE_DEVICE,
  20         USB_PHY_TYPE_HOST,
  21 };
  22
  23 static int s3c_usb_otgphy_init(struct platform_device *pdev)
  24 {
  25         struct clk *xusbxti;
  26         u32 phyclk;
  27
  28         writel(readl(S3C64XX_OTHERS) | S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);
  29
  30         /* set clock frequency for PLL */
  31         phyclk = readl(S3C_PHYCLK) & ~S3C_PHYCLK_CLKSEL_MASK;
  32
  33         xusbxti = clk_get(&pdev->dev, "xusbxti");
  34         if (xusbxti && !IS_ERR(xusbxti)) {
  35                 switch (clk_get_rate(xusbxti)) {
  36                 case 12 * MHZ:
  37                         phyclk |= S3C_PHYCLK_CLKSEL_12M;
  38                         break;
  39                 case 24 * MHZ:
  40                         phyclk |= S3C_PHYCLK_CLKSEL_24M;
  41                         break;
  42                 default:
  43                 case 48 * MHZ:
  44                         /* default reference clock */
  45                         break;
  46                 }
  47                 clk_put(xusbxti);
  48         }
  49
  50         /* TODO: select external clock/oscillator */
  51         writel(phyclk | S3C_PHYCLK_CLK_FORCE, S3C_PHYCLK);
  52
  53         /* set to normal OTG PHY */
  54         writel((readl(S3C_PHYPWR) & ~S3C_PHYPWR_NORMAL_MASK), S3C_PHYPWR);
  55         mdelay(1);
  56
  57         /* reset OTG PHY and Link */
  58         writel(S3C_RSTCON_PHY | S3C_RSTCON_HCLK | S3C_RSTCON_PHYCLK,
  59                         S3C_RSTCON);
  60         udelay(20);     /* at-least 10uS */
  61         writel(0, S3C_RSTCON);
  62
  63         return 0;
  64 }
  65
  66 static int s3c_usb_otgphy_exit(struct platform_device *pdev)
  67 {
  68         writel((readl(S3C_PHYPWR) | S3C_PHYPWR_ANALOG_POWERDOWN |
  69                                 S3C_PHYPWR_OTG_DISABLE), S3C_PHYPWR);
  70
  71         writel(readl(S3C64XX_OTHERS) & ~S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);
  72
  73         return 0;
  74 }
  75
  76 int s3c_usb_phy_init(struct platform_device *pdev, int type)
  77 {
  78         if (type == USB_PHY_TYPE_DEVICE)
  79                 return s3c_usb_otgphy_init(pdev);
  80
  81         return -EINVAL;
  82 }
  83
  84 int s3c_usb_phy_exit(struct platform_device *pdev, int type)
  85 {
  86         if (type == USB_PHY_TYPE_DEVICE)
  87                 return s3c_usb_otgphy_exit(pdev);
  88
  89         return -EINVAL;
  90 }