From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leonard Crestez Subject: [RFC 3/8] cpufreq: imx6q: Set max suspend_freq to avoid changes during suspend Date: Wed, 22 Mar 2017 18:53:05 +0200 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Mark Brown , Liam Girdwood , Viresh Kumar , "Rafael J. Wysocki" , Shawn Guo , Sascha Hauer Cc: Mark Rutland , devicetree@vger.kernel.org, Leonard Crestez , Anson Huang , Irina Tirdea , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Octavian Purdila , Fabio Estevam , Robin Gong , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org If the cpufreq driver tries to modify voltage/freq during suspend/resume it might need to control an external PMIC via I2C or SPI but those devices might be already suspended. To avoid this scenario we just increase cpufreq to highest setpoint before suspend. This issue can easily be triggered by ldo-bypass but in theory any regulator set_voltage call can end up having to modify external supply voltages. Signed-off-by: Leonard Crestez --- drivers/cpufreq/imx6q-cpufreq.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c index be90ee3..e2c1fbf 100644 --- a/drivers/cpufreq/imx6q-cpufreq.c +++ b/drivers/cpufreq/imx6q-cpufreq.c @@ -162,6 +162,7 @@ static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) static int imx6q_cpufreq_init(struct cpufreq_policy *policy) { policy->clk = arm_clk; + policy->suspend_freq = freq_table[soc_opp_count - 1].frequency; return cpufreq_generic_init(policy, freq_table, transition_latency); } @@ -173,6 +174,7 @@ static struct cpufreq_driver imx6q_cpufreq_driver = { .init = imx6q_cpufreq_init, .name = "imx6q-cpufreq", .attr = cpufreq_generic_attr, + .suspend = cpufreq_generic_suspend, }; static int imx6q_cpufreq_probe(struct platform_device *pdev) -- 2.7.4