usb: renesas_usbhs: Don't disable the pipe if Control write status stage
authorYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tue, 26 May 2015 11:13:43 +0000 (20:13 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 31 May 2015 07:14:07 +0000 (16:14 +0900)
This patch fixes an issue that sometimes this controller is not able
to complete the Control write status stage.

This driver should enable DCPCTR.CCPL and PID_BUF to complete the status
stage. However, if this driver detects the ctrl_stage interruption first
before the control write data is received, this driver will clear the
PID_BUF wrongly in the usbhsf_pio_try_pop(). To avoid this issue, this
patch doesn't clear the PID_BUF in the usbhsf_pio_try_pop().
(Since also the privious code doesn't disable the PID_BUF after a control
 transfer was finished, this patch doesn't have any side efforts.)

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/renesas_usbhs/fifo.c

index 50f4e3a..fa126a2 100644 (file)
@@ -678,7 +678,14 @@ static int usbhsf_pio_try_pop(struct usbhs_pkt *pkt, int *is_done)
                *is_done = 1;
                usbhsf_rx_irq_ctrl(pipe, 0);
                usbhs_pipe_running(pipe, 0);
-               usbhs_pipe_disable(pipe);       /* disable pipe first */
+               /*
+                * If function mode, since this controller is possible to enter
+                * Control Write status stage at this timing, this driver
+                * should not disable the pipe. If such a case happens, this
+                * controller is not able to complete the status stage.
+                */
+               if (!usbhs_mod_is_host(priv) && !usbhs_pipe_is_dcp(pipe))
+                       usbhs_pipe_disable(pipe);       /* disable pipe first */
        }
 
        /*