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
   8 #include <linux/delay.h>
   9 #include <linux/io.h>
  10 #include "common.h"
  11 #include "rcar3.h"
  12
  13 #define LPSTS           0x102
  14 #define UGCTRL          0x180   /* 32-bit register */
  15 #define UGCTRL2         0x184   /* 32-bit register */
  16 #define UGSTS           0x188   /* 32-bit register */
  17
  18 /* Low Power Status register (LPSTS) */
  19 #define LPSTS_SUSPM     0x4000
  20
  21 /* R-Car D3 only: USB General control register (UGCTRL) */
  22 #define UGCTRL_PLLRESET         0x00000001
  23 #define UGCTRL_CONNECT          0x00000004
  24
  25 /*
  26  * USB General control register 2 (UGCTRL2)
  27  * Remarks: bit[31:11] and bit[9:6] should be 0
  28  */
  29 #define UGCTRL2_RESERVED_3      0x00000001      /* bit[3:0] should be B'0001 */
  30 #define UGCTRL2_USB0SEL_EHCI    0x00000010
  31 #define UGCTRL2_USB0SEL_HSUSB   0x00000020
  32 #define UGCTRL2_USB0SEL_OTG     0x00000030
  33 #define UGCTRL2_VBUSSEL         0x00000400
  34
  35 /* R-Car D3 only: USB General status register (UGSTS) */
  36 #define UGSTS_LOCK              0x00000100
  37
  38 static void usbhs_write32(struct usbhs_priv *priv, u32 reg, u32 data)
  39 {
  40         iowrite32(data, priv->base + reg);
  41 }
  42
  43 static u32 usbhs_read32(struct usbhs_priv *priv, u32 reg)
  44 {
  45         return ioread32(priv->base + reg);
  46 }
  47
  48 static void usbhs_rcar3_set_ugctrl2(struct usbhs_priv *priv, u32 val)
  49 {
  50         usbhs_write32(priv, UGCTRL2, val | UGCTRL2_RESERVED_3);
  51 }
  52
  53 static void usbhs_rcar3_set_usbsel(struct usbhs_priv *priv, bool ehci)
  54 {
  55         if (ehci)
  56                 usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_EHCI);
  57         else
  58                 usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_HSUSB);
  59 }
  60
  61 static int usbhs_rcar3_power_ctrl(struct platform_device *pdev,
  62                                 void __iomem *base, int enable)
  63 {
  64         struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
  65
  66         usbhs_rcar3_set_ugctrl2(priv, UGCTRL2_USB0SEL_OTG | UGCTRL2_VBUSSEL);
  67
  68         if (enable) {
  69                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
  70                 /* The controller on R-Car Gen3 needs to wait up to 45 usec */
  71                 udelay(45);
  72         } else {
  73                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
  74         }
  75
  76         return 0;
  77 }
  78
  79 /* R-Car D3 needs to release UGCTRL.PLLRESET */
  80 static int usbhs_rcar3_power_and_pll_ctrl(struct platform_device *pdev,
  81                                           void __iomem *base, int enable)
  82 {
  83         struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
  84         u32 val;
  85         int timeout = 1000;
  86         bool is_host = false;
  87
  88         if (enable) {
  89                 usbhs_write32(priv, UGCTRL, 0); /* release PLLRESET */
  90                 if (priv->edev)
  91                         is_host = extcon_get_state(priv->edev, EXTCON_USB_HOST);
  92
  93                 usbhs_rcar3_set_usbsel(priv, is_host);
  94
  95                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
  96                 do {
  97                         val = usbhs_read32(priv, UGSTS);
  98                         udelay(1);
  99                 } while (!(val & UGSTS_LOCK) && timeout--);
 100                 usbhs_write32(priv, UGCTRL, UGCTRL_CONNECT);
 101         } else {
 102                 usbhs_write32(priv, UGCTRL, 0);
 103                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
 104                 usbhs_write32(priv, UGCTRL, UGCTRL_PLLRESET);
 105         }
 106
 107         return 0;
 108 }
 109
 110 static int usbhs_rcar3_get_id(struct platform_device *pdev)
 111 {
 112         return USBHS_GADGET;
 113 }
 114
 115 static int usbhs_rcar3_notifier(struct notifier_block *nb, unsigned long event,
 116                                 void *data)
 117 {
 118         struct usbhs_priv *priv = container_of(nb, struct usbhs_priv, nb);
 119
 120         usbhs_rcar3_set_usbsel(priv, !!event);
 121
 122         return NOTIFY_DONE;
 123 }
 124
 125 const struct renesas_usbhs_platform_callback usbhs_rcar3_ops = {
 126         .power_ctrl = usbhs_rcar3_power_ctrl,
 127         .get_id = usbhs_rcar3_get_id,
 128 };
 129
 130 const struct renesas_usbhs_platform_callback usbhs_rcar3_with_pll_ops = {
 131         .power_ctrl = usbhs_rcar3_power_and_pll_ctrl,
 132         .get_id = usbhs_rcar3_get_id,
 133         .notifier = usbhs_rcar3_notifier,
 134 };