clk: vc5: Abort clock configuration without upstream clock

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>
This commit is contained in:
Marek Vasut 2018-12-15 01:55:19 +01:00 committed by Stephen Boyd
parent c6e909972e
commit 2137a109a5
1 changed files with 3 additions and 1 deletions

View File

@ -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);