4.14-stable review patch. If anyone has any objections, please let me know.
------------------
[ 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+renesas@gmail.com Cc: Alexey Firago alexey_firago@mentor.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Stephen Boyd sboyd@kernel.org Cc: linux-renesas-soc@vger.kernel.org [sboyd@kernel.org: Added comment about probe preventing this from happening in the first place] Signed-off-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Sasha Levin sashal@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 decffb3826ece..a738af893532f 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);