A function is allowed to return NAKs during the DATA stage to control data flow control. NAKs during the STATUS stage signal the function is still processing the request.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de --- drivers/usb/host/dwc2.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-)
diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c index 5ef6deb..db3acd4 100644 --- a/drivers/usb/host/dwc2.c +++ b/drivers/usb/host/dwc2.c @@ -892,8 +892,8 @@ static int _submit_control_msg(struct dwc2_priv *priv, struct usb_device *dev, { int devnum = usb_pipedevice(pipe); int pid, ret, act_len; - /* For CONTROL endpoint pid should start with DATA1 */ int status_direction; + unsigned long timeout;
if (devnum == priv->root_hub_devnum) { dev->status = 0; @@ -907,26 +907,37 @@ static int _submit_control_msg(struct dwc2_priv *priv, struct usb_device *dev, if (ret) return ret;
+ timeout = get_timer(0) + USB_TIMEOUT_MS(pipe); if (buffer) { + /* DATA stage */ pid = DWC2_HC_PID_DATA1; - ret = chunk_msg(priv, dev, pipe, &pid, usb_pipein(pipe), buffer, - len, false); + act_len = 0; + do { + if (get_timer(0) > timeout) { + printf("Timeout during CONTROL DATA stage\n"); + return -ETIMEDOUT; + } + ret = chunk_msg(priv, dev, pipe, &pid, usb_pipein(pipe), + buffer, len, false); + act_len += dev->act_len; + buffer += dev->act_len; + len -= dev->act_len; + } while (len && (ret == -EAGAIN)); if (ret) return ret; - act_len = dev->act_len; - } /* End of DATA stage */ - else + status_direction = usb_pipeout(pipe); + } else { + /* No-data CONTROL always ends with an IN transaction */ + status_direction = 1; act_len = 0; + }
/* STATUS stage */ - if ((len == 0) || usb_pipeout(pipe)) - status_direction = 1; - else - status_direction = 0; - pid = DWC2_HC_PID_DATA1; - ret = chunk_msg(priv, dev, pipe, &pid, status_direction, - priv->status_buffer, 0, false); + do { + ret = chunk_msg(priv, dev, pipe, &pid, status_direction, + priv->status_buffer, 0, false); + } while (ret == -EAGAIN); if (ret) return ret;