[dpdk-dev] [DPDK] /driver/bus/ifpga: fix driver probe failure handler

[AndyPei]

In the original code, when a device probe a driver,
if the driver in the driver list does not support
this device, a error is returned.
After this patch, a device wil try to match driver
in the driver list one by one until an appropriate
driver is found. If the current driver does not
support the device or some error happens, just try
the next driver in the list.
If all the drivers in the list are tried and no
driver matches. 0 is returned.

fixes: 05fa3d4a6539
cc: rosen.xu at intel.com
cc: tianfei.zhang at intel.com
cc: andy.pei at intel.com

Signed-off-by: AndyPei <andy.pei at intel.com>
---
 drivers/bus/ifpga/ifpga_bus.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/bus/ifpga/ifpga_bus.c b/drivers/bus/ifpga/ifpga_bus.c
index e4b7b6f..55d3abf 100644
--- a/drivers/bus/ifpga/ifpga_bus.c
+++ b/drivers/bus/ifpga/ifpga_bus.c
@@ -306,12 +306,19 @@ void rte_ifpga_driver_unregister(struct rte_afu_driver *driver)
 	}
 
 	TAILQ_FOREACH(drv, &ifpga_afu_drv_list, next) {
-		if (ifpga_probe_one_driver(drv, afu_dev)) {
-			ret = -1;
-			break;
-		}
+		ret = ifpga_probe_one_driver(drv, afu_dev);
+		if (ret < 0)
+			/* negative value is an error */
+			return ret;
+		if (ret > 0)
+			/* positive value means driver doesn't support it */
+			continue;
+		return 0;
 	}
-	return ret;
+	if ((ret > 0) && (afu_dev->driver == NULL))
+		return 0;
+	else
+		return ret;
 }
 
 /*
-- 
1.8.3.1