From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: [RFC] cpufreq: Make sure target freq is within limits Date: Thu, 25 Oct 2012 12:03:34 +0530 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linaro-dev-bounces-cunTk1MwBs8s++Sfvej+rw@public.gmane.org Errors-To: linaro-dev-bounces-cunTk1MwBs8s++Sfvej+rw@public.gmane.org To: rjw-KKrjLPT3xs0@public.gmane.org Cc: linaro-dev-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, patches-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, Viresh Kumar , linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cpufreq-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, pdsw-power-team-5wv7dgnIgG8@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-pm@vger.kernel.org Hi Rafael, __cpufreq_driver_target() must not pass target frequency beyond the limits of current policy. Today most of cpufreq platform drivers are doing this check in their target routines. Why not move it to __cpufreq_driver_target(). I wanted to get your opinion on this before making changes in all driver files. That's why this is an RFC. Signed-off-by: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index f552d5f..59264f1 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1470,12 +1470,19 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int relation) { int retval = -EINVAL; + unsigned int old_target_freq = target_freq; if (cpufreq_disabled()) return -ENODEV; - pr_debug("target for CPU %u: %u kHz, relation %u\n", policy->cpu, - target_freq, relation); + /* Make sure that target_freq is within supported range */ + if (target_freq > policy->max) + target_freq = policy->max; + if (target_freq < policy->min) + target_freq = policy->min; + + pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", + policy->cpu, target_freq, relation, old_target_freq); if (cpu_online(policy->cpu) && cpufreq_driver->target) retval = cpufreq_driver->target(policy, target_freq, relation); -- 1.7.12.rc2.18.g61b472e