drivers/usb/renesas_usbhs/rcar3.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Renesas USB driver R-Car Gen. 3 initialization and power control
   4  *
   5  * Copyright (C) 2016 Renesas Electronics Corporation
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/io.h>
  15 #include "common.h"
  16 #include "rcar3.h"
  17
  18 #define LPSTS           0x102
  19 #define UGCTRL          0x180   /* 32-bit register */
  20 #define UGCTRL2         0x184   /* 32-bit register */
  21 #define UGSTS           0x188   /* 32-bit register */
  22
  23 /* Low Power Status register (LPSTS) */
  24 #define LPSTS_SUSPM     0x4000
  25
  26 /* R-Car D3 only: USB General control register (UGCTRL) */
  27 #define UGCTRL_PLLRESET         0x00000001
  28 #define UGCTRL_CONNECT          0x00000004
  29
  30 /*
  31  * USB General control register 2 (UGCTRL2)
  32  * Remarks: bit[31:11] and bit[9:6] should be 0
  33  */
  34 #define UGCTRL2_RESERVED_3      0x00000001      /* bit[3:0] should be B'0001 */
  35 #define UGCTRL2_USB0SEL_HSUSB   0x00000020
  36 #define UGCTRL2_USB0SEL_OTG     0x00000030
  37 #define UGCTRL2_VBUSSEL         0x00000400
  38
  39 /* R-Car D3 only: USB General status register (UGSTS) */
  40 #define UGSTS_LOCK              0x00000100
  41
  42 static void usbhs_write32(struct usbhs_priv *priv, u32 reg, u32 data)
  43 {
  44         iowrite32(data, priv->base + reg);
  45 }
  46
  47 static u32 usbhs_read32(struct usbhs_priv *priv, u32 reg)
  48 {
  49         return ioread32(priv->base + reg);
  50 }
  51
  52 static int usbhs_rcar3_power_ctrl(struct platform_device *pdev,
  53                                 void __iomem *base, int enable)
  54 {
  55         struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
  56
  57         usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 | UGCTRL2_USB0SEL_OTG |
  58                       UGCTRL2_VBUSSEL);
  59
  60         if (enable) {
  61                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
  62                 /* The controller on R-Car Gen3 needs to wait up to 45 usec */
  63                 udelay(45);
  64         } else {
  65                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
  66         }
  67
  68         return 0;
  69 }
  70
  71 /* R-Car D3 needs to release UGCTRL.PLLRESET */
  72 static int usbhs_rcar3_power_and_pll_ctrl(struct platform_device *pdev,
  73                                           void __iomem *base, int enable)
  74 {
  75         struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
  76         u32 val;
  77         int timeout = 1000;
  78
  79         if (enable) {
  80                 usbhs_write32(priv, UGCTRL, 0); /* release PLLRESET */
  81                 usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 |
  82                               UGCTRL2_USB0SEL_HSUSB);
  83
  84                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
  85                 do {
  86                         val = usbhs_read32(priv, UGSTS);
  87                         udelay(1);
  88                 } while (!(val & UGSTS_LOCK) && timeout--);
  89                 usbhs_write32(priv, UGCTRL, UGCTRL_CONNECT);
  90         } else {
  91                 usbhs_write32(priv, UGCTRL, 0);
  92                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
  93                 usbhs_write32(priv, UGCTRL, UGCTRL_PLLRESET);
  94         }
  95
  96         return 0;
  97 }
  98
  99 static int usbhs_rcar3_get_id(struct platform_device *pdev)
 100 {
 101         return USBHS_GADGET;
 102 }
 103
 104 const struct renesas_usbhs_platform_callback usbhs_rcar3_ops = {
 105         .power_ctrl = usbhs_rcar3_power_ctrl,
 106         .get_id = usbhs_rcar3_get_id,
 107 };
 108
 109 const struct renesas_usbhs_platform_callback usbhs_rcar3_with_pll_ops = {
 110         .power_ctrl = usbhs_rcar3_power_and_pll_ctrl,
 111         .get_id = usbhs_rcar3_get_id,
 112 };