[Patch V4 10/19] usb: gadget: tegra-xudc: Add usb-phy support

From: Nagarjuna Kristam
Date: Tue Feb 04 2020 - 06:19:35 EST


usb-phy is used to get notified on the USB role changes. Get usb-phy from
the UTMI PHY.

Signed-off-by: Nagarjuna Kristam <nkristam@xxxxxxxxxx>
---
V4:
- Addressed nit comments from Thierry.
- usb_phy_event is used to detect device mode instead of usb_role.
---
V2-V3:
- No changes in this version
---
drivers/usb/gadget/udc/tegra-xudc.c | 48 ++++++++++++++++++++++++++++++++++---
1 file changed, 45 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c
index acecdcf..7411dd15 100644
--- a/drivers/usb/gadget/udc/tegra-xudc.c
+++ b/drivers/usb/gadget/udc/tegra-xudc.c
@@ -26,7 +26,9 @@
#include <linux/reset.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
+#include <linux/usb/otg.h>
#include <linux/usb/role.h>
+#include <linux/usb/phy.h>
#include <linux/workqueue.h>

/* XUSB_DEV registers */
@@ -487,6 +489,9 @@ struct tegra_xudc {
bool suspended;
bool powergated;

+ struct usb_phy *usbphy;
+ struct notifier_block vbus_nb;
+
struct completion disconnect_complete;

bool selfpowered;
@@ -669,6 +674,31 @@ static void tegra_xudc_usb_role_sw_work(struct work_struct *work)
tegra_xudc_device_mode_off(xudc);
}

+static int tegra_xudc_vbus_notify(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct tegra_xudc *xudc = container_of(nb, struct tegra_xudc,
+ vbus_nb);
+ struct usb_phy *usbphy = (struct usb_phy *)data;
+
+ dev_dbg(xudc->dev, "%s(): event is %d\n", __func__, usbphy->last_event);
+
+ if ((xudc->device_mode && usbphy->last_event == USB_EVENT_VBUS) ||
+ (!xudc->device_mode && usbphy->last_event != USB_EVENT_VBUS)) {
+ dev_dbg(xudc->dev, "Same role(%d) received. Ignore",
+ xudc->device_mode);
+ return NOTIFY_OK;
+ }
+
+ xudc->device_mode = (usbphy->last_event == USB_EVENT_VBUS) ? true :
+ false;
+
+ if (!xudc->suspended)
+ schedule_work(&xudc->usb_role_sw_work);
+
+ return NOTIFY_OK;
+}
+
static void tegra_xudc_plc_reset_work(struct work_struct *work)
{
struct delayed_work *dwork = to_delayed_work(work);
@@ -1937,6 +1967,9 @@ static int tegra_xudc_gadget_start(struct usb_gadget *gadget,
xudc_writel(xudc, val, CTRL);
}

+ if (xudc->usbphy)
+ otg_set_peripheral(xudc->usbphy->otg, gadget);
+
xudc->driver = driver;
unlock:
dev_dbg(xudc->dev, "%s: ret value is %d", __func__, ret);
@@ -1957,6 +1990,9 @@ static int tegra_xudc_gadget_stop(struct usb_gadget *gadget)

spin_lock_irqsave(&xudc->lock, flags);

+ if (xudc->usbphy)
+ otg_set_peripheral(xudc->usbphy->otg, NULL);
+
val = xudc_readl(xudc, CTRL);
val &= ~(CTRL_IE | CTRL_ENABLE);
xudc_writel(xudc, val, CTRL);
@@ -3561,9 +3597,15 @@ static int tegra_xudc_probe(struct platform_device *pdev)
INIT_DELAYED_WORK(&xudc->port_reset_war_work,
tegra_xudc_port_reset_war_work);

- /* Set the mode as device mode and this keeps phy always ON */
- xudc->device_mode = true;
- schedule_work(&xudc->usb_role_sw_work);
+ xudc->vbus_nb.notifier_call = tegra_xudc_vbus_notify;
+ xudc->usbphy = devm_usb_get_phy_by_node(xudc->dev,
+ xudc->utmi_phy->dev.of_node,
+ &xudc->vbus_nb);
+ if (IS_ERR(xudc->usbphy)) {
+ err = PTR_ERR(xudc->usbphy);
+ dev_err(xudc->dev, "failed to get USB PHY: %d\n", err);
+ goto free_eps;
+ }

pm_runtime_enable(&pdev->dev);

--
2.7.4