linux-kernel - [PATCH] clk: sunxi: Fix operator precedence in sunxi_divs_clk

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Message-Id: <20191022165054.48302-1-natechancellor@gmail.com>
Date:   Tue, 22 Oct 2019 09:50:54 -0700
From:   Nathan Chancellor <natechancellor@...il.com>
To:     Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>
Cc:     Emilio López <emilio@...pez.com.ar>,
        Maxime Ripard <mripard@...nel.org>,
        Chen-Yu Tsai <wens@...e.org>, linux-clk@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        clang-built-linux@...glegroups.com,
        Nathan Chancellor <natechancellor@...il.com>
Subject: [PATCH] clk: sunxi: Fix operator precedence in sunxi_divs_clk_setup

r375326 in Clang exposes an issue with operator precedence in
sunxi_div_clk_setup:

drivers/clk/sunxi/clk-sunxi.c:1083:30: warning: operator '?:' has lower
precedence than '|'; '|' will be evaluated first
[-Wbitwise-conditional-parentheses]
                                                 data->div[i].critical ?
                                                 ~~~~~~~~~~~~~~~~~~~~~ ^
drivers/clk/sunxi/clk-sunxi.c:1083:30: note: place parentheses around
the '|' expression to silence this warning
                                                 data->div[i].critical ?
                                                                       ^
                                                                      )
drivers/clk/sunxi/clk-sunxi.c:1083:30: note: place parentheses around
the '?:' expression to evaluate it first
                                                 data->div[i].critical ?
                                                                       ^
                                                 (
1 warning generated.

It appears that the intention was for ?: to be evaluated first so that
CLK_IS_CRITICAL could be added to clkflags if the critical boolean was
set; right now, | is being evaluated first. Add parentheses around the
?: block to have it be evaluated first.

Fixes: 9919d44ff297 ("clk: sunxi: Use CLK_IS_CRITICAL flag for critical clks")
Link: https://github.com/ClangBuiltLinux/linux/issues/745
Signed-off-by: Nathan Chancellor <natechancellor@...il.com>
---
 drivers/clk/sunxi/clk-sunxi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index d3a43381a792..27201fd26e44 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -1080,8 +1080,8 @@ static struct clk ** __init sunxi_divs_clk_setup(struct device_node *node,
 						 rate_hw, rate_ops,
 						 gate_hw, &clk_gate_ops,
 						 clkflags |
-						 data->div[i].critical ?
-							CLK_IS_CRITICAL : 0);
+						 (data->div[i].critical ?
+							CLK_IS_CRITICAL : 0));
 
 		WARN_ON(IS_ERR(clk_data->clks[i]));
 	}
-- 
2.23.0