fpga: zynq-fpga: Fix issue with drvdata being overwritten.

Upon registering a FPGA Manager low level driver, FPGA Manager
core overwrites the platform drvdata pointer. Prior to this commit
zynq-fpga falsely relied on this pointer to still be valid at remove()
time.

Reported-by: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Acked-by: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c
index 31db5509f3d4..c2fb4120bd62 100644
--- a/drivers/fpga/zynq-fpga.c
+++ b/drivers/fpga/zynq-fpga.c
@@ -416,7 +416,6 @@ static int zynq_fpga_probe(struct platform_device *pdev)
         if (!priv)
                 return -ENOMEM;
 
-        platform_set_drvdata(pdev, priv);
         priv->dev = dev;
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -477,10 +476,12 @@ static int zynq_fpga_probe(struct platform_device *pdev)
 static int zynq_fpga_remove(struct platform_device *pdev)
 {
         struct zynq_fpga_priv *priv;
+        struct fpga_manager *mgr;
 
-        fpga_mgr_unregister(&pdev->dev);
+        mgr = platform_get_drvdata(pdev);
+        priv = mgr->priv;
 
-        priv = platform_get_drvdata(pdev);
+        fpga_mgr_unregister(&pdev->dev);
 
         clk_unprepare(priv->clk);