From: Marek Vasut <marek.va...@gmail.com>
[ Upstream commit 2137a109a5e39c2bdccfffe65230ed3fadbaac0e ]
In case the upstream clock are not set, which can happen in case the
VC5 has no valid upstream clock, the $src variable is used uninited
by regmap_update_bits(). Check for this condition and return -EINVAL
in such case.
Note that in case the VC5 has no valid upstream clock, the VC5 can
not operate correctly. That is a hardware property of the VC5. The
internal oscilator present in some VC5 models is also considered
upstream clock.
Signed-off-by: Marek Vasut <marek.vasut+rene...@gmail.com>
Cc: Alexey Firago <alexey_fir...@mentor.com>
Cc: Laurent Pinchart <laurent.pinch...@ideasonboard.com>
Cc: Stephen Boyd <sb...@kernel.org>
Cc: linux-renesas-...@vger.kernel.org
[sb...@kernel.org: Added comment about probe preventing this from
happening in the first place]
Signed-off-by: Stephen Boyd <sb...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
drivers/clk/clk-versaclock5.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/clk-versaclock5.c b/drivers/clk/clk-versaclock5.c
index decffb3826ec..a738af893532 100644
--- a/drivers/clk/clk-versaclock5.c
+++ b/drivers/clk/clk-versaclock5.c
@@ -262,8 +262,10 @@ static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
src = VC5_PRIM_SRC_SHDN_EN_XTAL;
- if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
+ else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
+ else /* Invalid; should have been caught by vc5_probe() */
+ return -EINVAL;
}
return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
--
2.19.1
