drivers/usb/renesas_usbhs/rcar3.c

   1 /*
   2  * Renesas USB driver R-Car Gen. 3 initialization and power control
   3  *
   4  * Copyright (C) 2016 Renesas Electronics Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <linux/delay.h>
  13 #include <linux/io.h>
  14 #include "common.h"
  15 #include "rcar3.h"
  16
  17 #define LPSTS           0x102
  18 #define UGCTRL2         0x184   /* 32-bit register */
  19
  20 /* Low Power Status register (LPSTS) */
  21 #define LPSTS_SUSPM     0x4000
  22
  23 /* USB General control register 2 (UGCTRL2), bit[31:6] should be 0 */
  24 #define UGCTRL2_RESERVED_3      0x00000001      /* bit[3:0] should be B'0001 */
  25 #define UGCTRL2_USB0SEL_OTG     0x00000030
  26
  27 static void usbhs_write32(struct usbhs_priv *priv, u32 reg, u32 data)
  28 {
  29         iowrite32(data, priv->base + reg);
  30 }
  31
  32 static int usbhs_rcar3_power_ctrl(struct platform_device *pdev,
  33                                 void __iomem *base, int enable)
  34 {
  35         struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
  36
  37         usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 | UGCTRL2_USB0SEL_OTG);
  38
  39         if (enable) {
  40                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
  41                 /* The controller on R-Car Gen3 needs to wait up to 45 usec */
  42                 udelay(45);
  43         } else {
  44                 usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
  45         }
  46
  47         return 0;
  48 }
  49
  50 static int usbhs_rcar3_get_id(struct platform_device *pdev)
  51 {
  52         return USBHS_GADGET;
  53 }
  54
  55 const struct renesas_usbhs_platform_callback usbhs_rcar3_ops = {
  56         .power_ctrl = usbhs_rcar3_power_ctrl,
  57         .get_id = usbhs_rcar3_get_id,
  58 };