Re: [PATCH 1/2] cpufreq: mediatek: Add MT8173 cpufreq driver

From: Pi-Cheng Chen
Date: Thu May 07 2015 - 05:40:45 EST


On Thu, Apr 30, 2015 at 3:42 PM, Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote:
> On Mon, Apr 20, 2015 at 05:27:26PM +0800, pi-cheng.chen wrote:
>> This patch implements MT8173 specific cpufreq driver with OPP table defined
>> in the driver code.
>>
>> Signed-off-by: pi-cheng.chen <pi-cheng.chen@xxxxxxxxxx>
>> ---
>> drivers/cpufreq/Kconfig.arm | 6 +
>> drivers/cpufreq/Makefile | 1 +
>> drivers/cpufreq/mt8173-cpufreq.c | 509 +++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 516 insertions(+)
>> create mode 100644 drivers/cpufreq/mt8173-cpufreq.c
>>
>> diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
>> index 1b06fc4..25643c7 100644
>> --- a/drivers/cpufreq/Kconfig.arm
>> +++ b/drivers/cpufreq/Kconfig.arm
>> +
>> +static int mt8173_cpufreq_dvfs_init(struct cpu_dvfs_info *info)
>> +{
>> + struct device *cpu_dev;
>> + struct regulator *proc_reg, *sram_reg;
>> + struct clk *cpu_clk, *inter_pll;
>> + unsigned long rate;
>> + int cpu, ret;
>> +
>> + cpu = cpumask_first(&info->cpus);
>> +
>> +try_next_cpu:
>> + cpu_dev = get_cpu_device(cpu);
>> + proc_reg = regulator_get_exclusive(cpu_dev, "proc");
>> + sram_reg = regulator_get_exclusive(cpu_dev, "sram");
>> + cpu_clk = clk_get(cpu_dev, "cpu");
>> + inter_pll = clk_get(cpu_dev, "intermediate");
>> +
>> + if (IS_ERR_OR_NULL(proc_reg) || IS_ERR_OR_NULL(cpu_clk) ||
>> + IS_ERR_OR_NULL(inter_pll)) {
>> + cpu = cpumask_next(cpu, &info->cpus);
>> + if (cpu >= nr_cpu_ids)
>> + return -ENODEV;
>> +
>> + goto try_next_cpu;
>> + }
>
> Please keep an eye on the error pathes. This one is quite broken. You
> get references to resources here which you never release. Also
> -EPROBE_DEFER is a valid return value from regulator_get which is not
> handled here.
>
> Also IS_ERR_OR_NULL() is most probably wrong here. Should be IS_ERR().

I'll review the error handling path and fix them.
Thanks for reviewing.

Best Regards,
Pi-Cheng

>
> Sascha
>
> --
> Pengutronix e.K. | |
> Industrial Linux Solutions | http://www.pengutronix.de/ |
> Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/