linux-kernel - [PATCH] cpufreq: s3c64xx: Remove pointless NULL check in s3c64xx_cpufreq_driver

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Message-Id: <20191023000906.14374-1-natechancellor@gmail.com>
Date:   Tue, 22 Oct 2019 17:09:06 -0700
From:   Nathan Chancellor <natechancellor@...il.com>
To:     Kukjin Kim <kgene@...nel.org>,
        Krzysztof Kozlowski <krzk@...nel.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Viresh Kumar <viresh.kumar@...aro.org>
Cc:     linux-arm-kernel@...ts.infradead.org,
        linux-samsung-soc@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org, clang-built-linux@...glegroups.com,
        Nathan Chancellor <natechancellor@...il.com>
Subject: [PATCH] cpufreq: s3c64xx: Remove pointless NULL check in s3c64xx_cpufreq_driver_init

When building with Clang + -Wtautological-pointer-compare:

drivers/cpufreq/s3c64xx-cpufreq.c:152:6: warning: comparison of array
's3c64xx_freq_table' equal to a null pointer is always false
[-Wtautological-pointer-compare]
        if (s3c64xx_freq_table == NULL) {
            ^~~~~~~~~~~~~~~~~~    ~~~~
1 warning generated.

The definition of s3c64xx_freq_table is surrounded by an ifdef
directive for CONFIG_CPU_S3C6410, which is always true for this driver
because it depends on it in drivers/cpufreq/Kconfig.arm (and if it
weren't, there would be a build error because s3c64xx_freq_table would
not be a defined symbol).

Resolve this warning by removing the unnecessary NULL check because it
is always false as Clang notes. While we are at it, remove the
unnecessary ifdef conditional because it is always true.

Fixes: b3748ddd8056 ("[ARM] S3C64XX: Initial support for DVFS")
Link: https://github.com/ClangBuiltLinux/linux/issues/748
Signed-off-by: Nathan Chancellor <natechancellor@...il.com>
---
 drivers/cpufreq/s3c64xx-cpufreq.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/cpufreq/s3c64xx-cpufreq.c b/drivers/cpufreq/s3c64xx-cpufreq.c
index af0c00dabb22..c6bdfc308e99 100644
--- a/drivers/cpufreq/s3c64xx-cpufreq.c
+++ b/drivers/cpufreq/s3c64xx-cpufreq.c
@@ -19,7 +19,6 @@
 static struct regulator *vddarm;
 static unsigned long regulator_latency;
 
-#ifdef CONFIG_CPU_S3C6410
 struct s3c64xx_dvfs {
 	unsigned int vddarm_min;
 	unsigned int vddarm_max;
@@ -48,7 +47,6 @@ static struct cpufreq_frequency_table s3c64xx_freq_table[] = {
 	{ 0, 4, 800000 },
 	{ 0, 0, CPUFREQ_TABLE_END },
 };
-#endif
 
 static int s3c64xx_cpufreq_set_target(struct cpufreq_policy *policy,
 				      unsigned int index)
@@ -149,11 +147,6 @@ static int s3c64xx_cpufreq_driver_init(struct cpufreq_policy *policy)
 	if (policy->cpu != 0)
 		return -EINVAL;
 
-	if (s3c64xx_freq_table == NULL) {
-		pr_err("No frequency information for this CPU\n");
-		return -ENODEV;
-	}
-
 	policy->clk = clk_get(NULL, "armclk");
 	if (IS_ERR(policy->clk)) {
 		pr_err("Unable to obtain ARMCLK: %ld\n",
-- 
2.23.0