From mboxrd@z Thu Jan 1 00:00:00 1970 From: viresh.kumar@linaro.org (Viresh Kumar) Date: Mon, 30 Nov 2015 10:57:51 +0530 Subject: [PATCH 3/4] cpufreq: mt8173: check return value of regulator_get_voltage() call In-Reply-To: <1448785898-17838-3-git-send-email-pi-cheng.chen@linaro.org> References: <1448785898-17838-1-git-send-email-pi-cheng.chen@linaro.org> <1448785898-17838-3-git-send-email-pi-cheng.chen@linaro.org> Message-ID: <20151130052751.GK3373@ubuntu> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 29-11-15, 16:31, Pi-Cheng Chen wrote: > Sometimes regulator_get_voltage() call returns negative values for > reasons(e.g. underlying I2C bus timeout). Add check for the return > values and fail out early. > > Signed-off-by: Pi-Cheng Chen > --- > drivers/cpufreq/mt8173-cpufreq.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c > index 750cda7..9d0fe37 100644 > --- a/drivers/cpufreq/mt8173-cpufreq.c > +++ b/drivers/cpufreq/mt8173-cpufreq.c > @@ -59,6 +59,10 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, > int old_vproc, old_vsram, new_vsram, vsram, vproc, ret; > > old_vproc = regulator_get_voltage(proc_reg); > + if (old_vproc < 0) { > + pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); > + return old_vproc; > + } > /* Vsram should not exceed the maximum allowed voltage of SoC. */ > new_vsram = min(new_vproc + MIN_VOLT_SHIFT, MAX_VOLT_LIMIT); > > @@ -71,7 +75,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, > */ > do { > old_vsram = regulator_get_voltage(sram_reg); > + if (old_vsram < 0) { > + pr_err("%s: invalid Vsram value: %d\n", > + __func__, old_vsram); > + return old_vsram; > + } > old_vproc = regulator_get_voltage(proc_reg); > + if (old_vproc < 0) { > + pr_err("%s: invalid Vproc value: %d\n", > + __func__, old_vproc); > + return old_vproc; > + } > > vsram = min(new_vsram, old_vproc + MAX_VOLT_SHIFT); > > @@ -116,7 +130,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, > */ > do { > old_vproc = regulator_get_voltage(proc_reg); > + if (old_vproc < 0) { > + pr_err("%s: invalid Vproc value: %d\n", > + __func__, old_vproc); > + return old_vproc; > + } > old_vsram = regulator_get_voltage(sram_reg); > + if (old_vsram < 0) { > + pr_err("%s: invalid Vsram value: %d\n", > + __func__, old_vsram); > + return old_vsram; > + } > > vproc = max(new_vproc, old_vsram - MAX_VOLT_SHIFT); > ret = regulator_set_voltage(proc_reg, vproc, > @@ -184,6 +208,10 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > > old_freq_hz = clk_get_rate(cpu_clk); > old_vproc = regulator_get_voltage(info->proc_reg); > + if (old_vproc < 0) { > + pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); > + return old_vproc; > + } > > freq_hz = freq_table[index].frequency * 1000; Acked-by: Viresh Kumar -- viresh