staging: comedi: ni_tio: fix warnings of uninitialized variables

Fix the following warnings by initializing these variables
to zero and add error check to return early when the check
returns an error.

drivers/staging/comedi/drivers/ni_tio.c: In function ‘ni_tio_set_sync_mode’:
drivers/staging/comedi/drivers/ni_tio.c:492:28: warning: ‘ps’ may be used uninitialized in this function [-Wuninitialized]
drivers/staging/comedi/drivers/ni_tio.c: In function ‘ni_tio_insn_config’:
drivers/staging/comedi/drivers/ni_tio.c:820:2: warning: ‘temp64’ may be used uninitialized in this function [-Wuninitialized]
drivers/staging/comedi/drivers/ni_tio.c:811:6: note: ‘temp64’ was declared her

Signed-off-by: Ted Chen <tedc.37zngo@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/ni_tio.c b/drivers/staging/comedi/drivers/ni_tio.c
index 7043eb0543f6b15c98161e341b354a05e7748e02..15ca0323ddd9150b4c589f5f05d5f6348e65556f 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_tio.c
+++ b/drivers/staging/comedi/drivers/ni_tio.c
@@ -451,8 +451,9 @@ static void ni_tio_set_sync_mode(struct ni_gpct *counter)
        unsigned int bits = 0;
        unsigned int reg;
        unsigned int mode;
-       unsigned int clk_src;
-       u64 ps;
+       unsigned int clk_src = 0;
+       u64 ps = 0;
+       int ret;
        bool force_alt_sync;
 
        /* only m series and 660x variants have counting mode registers */
@@ -482,9 +483,12 @@ static void ni_tio_set_sync_mode(struct ni_gpct *counter)
                break;
        }
 
-       ni_tio_generic_clock_src_select(counter, &clk_src);
-       ni_tio_clock_period_ps(counter, clk_src, &ps);
-
+       ret = ni_tio_generic_clock_src_select(counter, &clk_src);
+       if (ret)
+               return;
+       ret = ni_tio_clock_period_ps(counter, clk_src, &ps);
+       if (ret)
+               return;
        /*
         * It's not clear what we should do if clock_period is unknown, so we
         * are not using the alt sync bit in that case.
@@ -808,7 +812,7 @@ static int ni_tio_get_clock_src(struct ni_gpct *counter,
                                unsigned int *clock_source,
                                unsigned int *period_ns)
 {
-       u64 temp64;
+       u64 temp64 = 0;
        int ret;
 
        ret = ni_tio_generic_clock_src_select(counter, clock_source);