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| author | Arve Hjønnevåg <arve@android.com> | 2011-06-24 16:04:16 +0900 |
|---|---|---|
| committer | Dave Jones <davej@redhat.com> | 2011-07-13 18:29:58 -0400 |
| commit | 5b02b7794b555e299c5e9298c6b223b538888ec8 (patch) | |
| tree | ae2abbea1e4fc0ac98a544d058c3d0689b01cef0 /drivers/cpufreq | |
| parent | 405e6d6df739a27a267b381213aa9e86c4929543 (diff) | |
| download | kernel_samsung_smdk4412-5b02b7794b555e299c5e9298c6b223b538888ec8.zip kernel_samsung_smdk4412-5b02b7794b555e299c5e9298c6b223b538888ec8.tar.gz kernel_samsung_smdk4412-5b02b7794b555e299c5e9298c6b223b538888ec8.tar.bz2 | |
[CPUFREQ] S5PV210: Lock a mutex while changing the cpu frequency
Without this lock the call to change the frequency for suspend could
switch to a new frequency while another thread was still changing the
cpu voltage.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/s5pv210-cpufreq.c | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c index 79b1b4e..7fba356 100644 --- a/drivers/cpufreq/s5pv210-cpufreq.c +++ b/drivers/cpufreq/s5pv210-cpufreq.c @@ -26,6 +26,7 @@ static struct clk *cpu_clk; static struct clk *dmc0_clk; static struct clk *dmc1_clk; static struct cpufreq_freqs freqs; +static DEFINE_MUTEX(set_freq_lock); /* APLL M,P,S values for 1G/800Mhz */ #define APLL_VAL_1000 ((1 << 31) | (125 << 16) | (3 << 8) | 1) @@ -199,6 +200,8 @@ static int s5pv210_target(struct cpufreq_policy *policy, int arm_volt, int_volt; int ret = 0; + mutex_lock(&set_freq_lock); + if (relation & ENABLE_FURTHER_CPUFREQ) no_cpufreq_access = false; @@ -207,7 +210,8 @@ static int s5pv210_target(struct cpufreq_policy *policy, pr_err("%s:%d denied access to %s as it is disabled" "temporarily\n", __FILE__, __LINE__, __func__); #endif - return -EINVAL; + ret = -EINVAL; + goto exit; } if (relation & DISABLE_FURTHER_CPUFREQ) @@ -218,19 +222,23 @@ static int s5pv210_target(struct cpufreq_policy *policy, freqs.old = s5pv210_getspeed(0); if (cpufreq_frequency_table_target(policy, s5pv210_freq_table, - target_freq, relation, &index)) - return -EINVAL; + target_freq, relation, &index)) { + ret = -EINVAL; + goto exit; + } freqs.new = s5pv210_freq_table[index].frequency; freqs.cpu = 0; if (freqs.new == freqs.old) - return 0; + goto exit; /* Finding current running level index */ if (cpufreq_frequency_table_target(policy, s5pv210_freq_table, - freqs.old, relation, &priv_index)) - return -EINVAL; + freqs.old, relation, &priv_index)) { + ret = -EINVAL; + goto exit; + } arm_volt = dvs_conf[index].arm_volt; int_volt = dvs_conf[index].int_volt; @@ -239,12 +247,12 @@ static int s5pv210_target(struct cpufreq_policy *policy, ret = regulator_set_voltage(arm_regulator, arm_volt, arm_volt_max); if (ret) - return ret; + goto exit; ret = regulator_set_voltage(int_regulator, int_volt, int_volt_max); if (ret) - return ret; + goto exit; } cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); @@ -471,7 +479,9 @@ static int s5pv210_target(struct cpufreq_policy *policy, printk(KERN_DEBUG "Perf changed[L%d]\n", index); - return 0; +exit: + mutex_unlock(&set_freq_lock); + return ret; } #ifdef CONFIG_PM |