target/linux/generic/backport-4.14/030-v4.17-0001-usb-dwc2-add-support-for-host-mode-external-vbus-sup.patch

   1 From 531ef5ebea96394ddb7f554d4d88e017dde30a59 Mon Sep 17 00:00:00 2001
   2 From: Amelie Delaunay <amelie.delaunay@st.com>
   3 Date: Tue, 13 Feb 2018 09:28:12 +0100
   4 Subject: [PATCH] usb: dwc2: add support for host mode external vbus supply
   5
   6 This patch adds a way to enable an external vbus supply in host mode,
   7 when dwc2 drvvbus signal is not used.
   8
   9 This patch is very similar to the one done in U-Boot dwc2 driver [1]. It
  10 also adds dynamic vbus supply management depending on the role and state
  11 of the core.
  12
  13 [1] https://lists.denx.de/pipermail/u-boot/2017-March/283434.html
  14
  15 Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
  16 Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
  17 ---
  18  drivers/usb/dwc2/core.h |  2 ++
  19  drivers/usb/dwc2/hcd.c  | 26 ++++++++++++++++++++++++++
  20  2 files changed, 28 insertions(+)
  21
  22 --- a/drivers/usb/dwc2/core.h
  23 +++ b/drivers/usb/dwc2/core.h
  24 @@ -777,6 +777,7 @@ struct dwc2_hregs_backup {
  25   * @plat:               The platform specific configuration data. This can be
  26   *                      removed once all SoCs support usb transceiver.
  27   * @supplies:           Definition of USB power supplies
  28 + * @vbus_supply:        Regulator supplying vbus.
  29   * @phyif:              PHY interface width
  30   * @lock:              Spinlock that protects all the driver data structures
  31   * @priv:              Stores a pointer to the struct usb_hcd
  32 @@ -914,6 +915,7 @@ struct dwc2_hsotg {
  33         struct usb_phy *uphy;
  34         struct dwc2_hsotg_plat *plat;
  35         struct regulator_bulk_data supplies[DWC2_NUM_SUPPLIES];
  36 +       struct regulator *vbus_supply;
  37         u32 phyif;
  38
  39         spinlock_t lock;
  40 --- a/drivers/usb/dwc2/hcd.c
  41 +++ b/drivers/usb/dwc2/hcd.c
  42 @@ -359,6 +359,23 @@ static void dwc2_gusbcfg_init(struct dwc
  43         dwc2_writel(usbcfg, hsotg->regs + GUSBCFG);
  44  }
  45
  46 +static int dwc2_vbus_supply_init(struct dwc2_hsotg *hsotg)
  47 +{
  48 +       hsotg->vbus_supply = devm_regulator_get_optional(hsotg->dev, "vbus");
  49 +       if (IS_ERR(hsotg->vbus_supply))
  50 +               return 0;
  51 +
  52 +       return regulator_enable(hsotg->vbus_supply);
  53 +}
  54 +
  55 +static int dwc2_vbus_supply_exit(struct dwc2_hsotg *hsotg)
  56 +{
  57 +       if (hsotg->vbus_supply)
  58 +               return regulator_disable(hsotg->vbus_supply);
  59 +
  60 +       return 0;
  61 +}
  62 +
  63  /**
  64   * dwc2_enable_host_interrupts() - Enables the Host mode interrupts
  65   *
  66 @@ -3346,6 +3363,7 @@ static void dwc2_conn_id_status_change(s
  67
  68         /* B-Device connector (Device Mode) */
  69         if (gotgctl & GOTGCTL_CONID_B) {
  70 +               dwc2_vbus_supply_exit(hsotg);
  71                 /* Wait for switch to device mode */
  72                 dev_dbg(hsotg->dev, "connId B\n");
  73                 if (hsotg->bus_suspended) {
  74 @@ -4455,6 +4473,9 @@ static int _dwc2_hcd_start(struct usb_hc
  75         }
  76
  77         spin_unlock_irqrestore(&hsotg->lock, flags);
  78 +
  79 +       dwc2_vbus_supply_init(hsotg);
  80 +
  81         return 0;
  82  }
  83
  84 @@ -4482,6 +4503,8 @@ static void _dwc2_hcd_stop(struct usb_hc
  85         clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
  86         spin_unlock_irqrestore(&hsotg->lock, flags);
  87
  88 +       dwc2_vbus_supply_exit(hsotg);
  89 +
  90         usleep_range(1000, 3000);
  91  }
  92
  93 @@ -4518,6 +4541,7 @@ static int _dwc2_hcd_suspend(struct usb_
  94                 hprt0 |= HPRT0_SUSP;
  95                 hprt0 &= ~HPRT0_PWR;
  96                 dwc2_writel(hprt0, hsotg->regs + HPRT0);
  97 +               dwc2_vbus_supply_exit(hsotg);
  98         }
  99
 100         /* Enter hibernation */
 101 @@ -4598,6 +4622,8 @@ static int _dwc2_hcd_resume(struct usb_h
 102                 spin_unlock_irqrestore(&hsotg->lock, flags);
 103                 dwc2_port_resume(hsotg);
 104         } else {
 105 +               dwc2_vbus_supply_init(hsotg);
 106 +
 107                 /* Wait for controller to correctly update D+/D- level */
 108                 usleep_range(3000, 5000);
 109