Jun 07 2011

[CPUFREQ] s5pv210-cpufreq.c: Add missing clk_put 

Author: Julia Lawall <julia@diku.dk>

The successive calls to clk_get each call clk_put in the case of failure,
but this is not done for subsequent error handling code.  The calls to
clk_get are moved to the end of the function, and appropriate gotos are
added.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// 
@r exists@
expression e1,e2;
statement S;
@@

e1 = clk_get@p1(...);
... when != e1 = e2
    when != clk_put(e1)
    when any
if (...) { ... when != clk_put(e1)
               when != if (...) { ... clk_put(e1) ... }
* return@p3 ...;
 } else S
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Kukjin Kim 
Signed-off-by: Dave Jones 

---
 drivers/cpufreq/s5pv210-cpufreq.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)
 
diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c
index ea35d3f..a7cb338 100644
--- a/drivers/cpufreq/s5pv210-cpufreq.c
+++ b/drivers/cpufreq/s5pv210-cpufreq.c
@@ -415,6 +415,7 @@ static int check_mem_type(void __iomem *dmc_reg)
 static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
 {
 	unsigned long mem_type;
+	int ret;
 
 	cpu_clk = clk_get(NULL, "armclk");
 	if (IS_ERR(cpu_clk))
@@ -422,19 +423,20 @@ static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
 
 	dmc0_clk = clk_get(NULL, "sclk_dmc0");
 	if (IS_ERR(dmc0_clk)) {
-		clk_put(cpu_clk);
-		return PTR_ERR(dmc0_clk);
+		ret = PTR_ERR(dmc0_clk);
+		goto out_dmc0;
 	}
 
 	dmc1_clk = clk_get(NULL, "hclk_msys");
 	if (IS_ERR(dmc1_clk)) {
-		clk_put(dmc0_clk);
-		clk_put(cpu_clk);
-		return PTR_ERR(dmc1_clk);
+		ret = PTR_ERR(dmc1_clk);
+		goto out_dmc1;
 	}
 
-	if (policy->cpu != 0)
-		return -EINVAL;
+	if (policy->cpu != 0) {
+		ret = -EINVAL;
+		goto out_dmc1;
+	}
 
 	/*
 	 * check_mem_type : This driver only support LPDDR & LPDDR2.
@@ -444,7 +446,8 @@ static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
 
 	if ((mem_type != LPDDR) && (mem_type != LPDDR2)) {
 		printk(KERN_ERR "CPUFreq doesn't support this memory type\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_dmc1;
 	}
 
 	/* Find current refresh counter and frequency each DMC */
@@ -461,6 +464,12 @@ static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
 	policy->cpuinfo.transition_latency = 40000;
 
 	return cpufreq_frequency_table_cpuinfo(policy, s5pv210_freq_table);
+
+out_dmc1:
+	clk_put(dmc0_clk);
+out_dmc0:
+	clk_put(cpu_clk);
+	return ret;
 }
 
 static struct cpufreq_driver s5pv210_driver = {

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