On some hardware the USB fails to initialize to sane state after
cold boot. We can detect this based on some unexpected interrupt bits,
and recover by re-initializing.
Signed-off-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
---
drivers/staging/octeon-usb/octeon-hcd.c | 30 +++++++++++++++++++++++++++---
1 file changed, 27 insertions(+), 3 deletions(-)
diff --git a/drivers/staging/octeon-usb/octeon-hcd.c b/drivers/staging/octeon-usb/octeon-hcd.c
index 54c23c4..7981c93 100644
--- a/drivers/staging/octeon-usb/octeon-hcd.c
+++ b/drivers/staging/octeon-usb/octeon-hcd.c
@@ -697,15 +697,20 @@ static int cvmx_usb_shutdown(struct cvmx_usb_state *usb)
* other access to the Octeon USB port is made. The port starts
* off in the disabled state.
*
+ * @dev: Pointer to struct device for logging purposes.
* @usb: Pointer to struct cvmx_usb_state.
*
* Returns: 0 or a negative error code.
*/
-static int cvmx_usb_initialize(struct cvmx_usb_state *usb)
+static int cvmx_usb_initialize(struct device *dev,
+ struct cvmx_usb_state *usb)
{
+ int retries = 0;
union cvmx_usbnx_clk_ctl usbn_clk_ctl;
+ union cvmx_usbcx_gintsts usbc_gintsts;
union cvmx_usbnx_usbp_ctl_status usbn_usbp_ctl_status;
+retry:
/*
* Power On Reset and PHY Initialization
*
@@ -952,7 +957,26 @@ static int cvmx_usb_initialize(struct cvmx_usb_state *usb)
cvmx_fifo_setup(usb);
- return 0;
+ /*
+ * If the controller is getting port events right after the reset, it
+ * means the initialization failed. Try resetting the controller again
+ * in such case. This is seen to happen after cold boot on DSR-1000N.
+ */
+ usbc_gintsts.u32 = cvmx_usb_read_csr32(usb,
+ CVMX_USBCX_GINTSTS(usb->index));
+ cvmx_usb_write_csr32(usb, CVMX_USBCX_GINTSTS(usb->index),
+ usbc_gintsts.u32);
+ dev_dbg(dev, "gintsts after reset: 0x%x\n", (int)usbc_gintsts.u32);
+ if (!usbc_gintsts.s.disconnint && !usbc_gintsts.s.prtint)
+ return 0;
+ if (retries++ >= 5)
+ return -EAGAIN;
+ dev_info(dev, "controller reset failed (gintsts=0x%x) - retrying\n",
+ (int)usbc_gintsts.u32);
+ msleep(50);
+ cvmx_usb_shutdown(usb);
+ msleep(50);
+ goto retry;
}
/**
@@ -3690,7 +3714,7 @@ static int octeon_usb_probe(struct platform_device *pdev)
priv->usb.idle_hardware_channels = 0xff;
}
- status = cvmx_usb_initialize(&priv->usb);
+ status = cvmx_usb_initialize(dev, &priv->usb);
if (status) {
dev_dbg(dev, "USB initialization failed with %d\n", status);
kfree(hcd);
--
2.2.0
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