From 5d04c883797209f566538e27441b2563afe4e9b9 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 23 Sep 2016 16:40:56 +0300 Subject: [PATCH] phy_sun4i_usb: set_mode: Allow using set_mode to force end the current session The sunxi musb has a bug where sometimes it will generate a babble error on device disconnect instead of a disconnect irq. When this happens the musb-controller switches from host mode to device mode (it clears MUSB_DEVCTL_SESSION and sets MUSB_DEVCTL_BDEVICE) and gets stuck in this state. Clearing this requires reporting Vbus low for 200 or more ms, but on some devices Vbus is simply always high (host-only mode, no Vbus control). This commit modifies sun4i_usb_phy_set_mode so that it will force end the current session when called with the current mode, before this commit calling set_mode with the current mode was a nop since id_det would stay the same resulting in the detect_work not doing anything. This allows the sunxi-musb glue to use sun4i_usb_phy_set_mode to force end the current session without changing the mode, to fixup the stuck state after a babble error. Signed-off-by: Hans de Goede Signed-off-by: Kishon Vijay Abraham I --- drivers/phy/phy-sun4i-usb.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c index fec34f5213c4..bf28a0fdd569 100644 --- a/drivers/phy/phy-sun4i-usb.c +++ b/drivers/phy/phy-sun4i-usb.c @@ -436,25 +436,31 @@ static int sun4i_usb_phy_set_mode(struct phy *_phy, enum phy_mode mode) { struct sun4i_usb_phy *phy = phy_get_drvdata(_phy); struct sun4i_usb_phy_data *data = to_sun4i_usb_phy_data(phy); + int new_mode; if (phy->index != 0) return -EINVAL; switch (mode) { case PHY_MODE_USB_HOST: - data->dr_mode = USB_DR_MODE_HOST; + new_mode = USB_DR_MODE_HOST; break; case PHY_MODE_USB_DEVICE: - data->dr_mode = USB_DR_MODE_PERIPHERAL; + new_mode = USB_DR_MODE_PERIPHERAL; break; case PHY_MODE_USB_OTG: - data->dr_mode = USB_DR_MODE_OTG; + new_mode = USB_DR_MODE_OTG; break; default: return -EINVAL; } - dev_info(&_phy->dev, "Changing dr_mode to %d\n", (int)data->dr_mode); + if (new_mode != data->dr_mode) { + dev_info(&_phy->dev, "Changing dr_mode to %d\n", new_mode); + data->dr_mode = new_mode; + } + + data->id_det = -1; /* Force reprocessing of id */ data->force_session_end = true; queue_delayed_work(system_wq, &data->detect, 0);