[PATCH] clk: st: avoid uninitialized variable use

From: Arnd Bergmann
Date: Mon Jan 25 2016 - 10:56:43 EST


My previous patch fixed some warnings about printing a couple
of variables that are always uninitialized in quadfs_pll_fs660c32_set_rate(),
but I now got a warning that only shows up in some configurations (i.e.
without gcc -Os) about the params.ndiv being used uninitialized in the
error case:

drivers/clk/st/clkgen-fsyn.c: In function 'quadfs_pll_fs660c32_set_rate':
drivers/clk/st/clkgen-fsyn.c:584:75: warning: 'params.ndiv' may be used uninitialized in this function [-Wmaybe-uninitialized]
drivers/clk/st/clkgen-fsyn.c:574:16: note: 'params.ndiv' was declared here

This changes the error handling so we bail for invalid arguments rather
than continuing with uninitialized data.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/clk/st/clkgen-fsyn.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/st/clkgen-fsyn.c b/drivers/clk/st/clkgen-fsyn.c
index ccb324d97160..dec4eaaecc00 100644
--- a/drivers/clk/st/clkgen-fsyn.c
+++ b/drivers/clk/st/clkgen-fsyn.c
@@ -574,12 +574,16 @@ static int quadfs_pll_fs660c32_set_rate(struct clk_hw *hw, unsigned long rate,
struct stm_fs params;
long hwrate = 0;
unsigned long flags = 0;
+ int ret;

if (!rate || !parent_rate)
return -EINVAL;

- if (!clk_fs660c32_vco_get_params(parent_rate, rate, &params))
- clk_fs660c32_vco_get_rate(parent_rate, &params, &hwrate);
+ ret = clk_fs660c32_vco_get_params(parent_rate, rate, &params);
+ if (ret)
+ return ret;
+
+ clk_fs660c32_vco_get_rate(parent_rate, &params, &hwrate);

pr_debug("%s: %s new rate %ld [ndiv=0x%x]\n",
__func__, clk_hw_get_name(hw),
--
2.7.0