Re: [PATCH V2] cpufreq: kyro: Release OPP tables on module removal

[Georgi Djakov]

On 2/27/19 12:04, Viresh Kumar wrote:
> Commit 5ad7346b4ae2 ("cpufreq: kryo: Add module remove and exit") made
> it possible to build the kyro cpufreq driver as a module, but it failed

Nit: s/kyro/kryo/ above and in the subject

> to release all the resources, i.e. OPP tables, when the module is
> unloaded.
> 
> This patch fixes it by releasing the OPP tables, by calling
> dev_pm_opp_put_supported_hw() for them, from the
> qcom_cpufreq_kryo_remove() routine. The array of pointers to the OPP
> tables is also allocated dynamically now in qcom_cpufreq_kryo_probe(),
> as the pointers will be required while releasing the resources.
> 
> Compile tested only.
> 
> Cc: 4.18+ <sta...@vger.kernel.org> # v4.18+
> Fixes: 5ad7346b4ae2 ("cpufreq: kryo: Add module remove and exit")
> Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
> ---
> V1->V2:
> - The previous version targeted a compile time issue of frame size but
>   this fixes a bug in the driver and needs to get applied to 4.18+
>   kernels.
> - This may go in 5.0 release.
> - Haven't included any Reviewed-by tags as there were many changes in
>   this version.
> 
>  drivers/cpufreq/qcom-cpufreq-kryo.c | 20 ++++++++++++++++++--
>  1 file changed, 18 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c 
> b/drivers/cpufreq/qcom-cpufreq-kryo.c
> index 2a3675c24032..65edbfd4d4a5 100644
> --- a/drivers/cpufreq/qcom-cpufreq-kryo.c
> +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c
> @@ -75,7 +75,7 @@ static enum _msm8996_version 
> qcom_cpufreq_kryo_get_msm_id(void)
>  
>  static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
>  {
> -     struct opp_table *opp_tables[NR_CPUS] = {0};
> +     struct opp_table **opp_tables;
>       enum _msm8996_version msm8996_version;
>       struct nvmem_cell *speedbin_nvmem;
>       struct device_node *np;
> @@ -133,6 +133,10 @@ static int qcom_cpufreq_kryo_probe(struct 
> platform_device *pdev)
>       }
>       kfree(speedbin);
>  
> +     opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables), 
> GFP_KERNEL);
> +     if (!opp_tables)
> +             return -ENOMEM;
> +
>       for_each_possible_cpu(cpu) {
>               cpu_dev = get_cpu_device(cpu);
>               if (NULL == cpu_dev) {
> @@ -151,8 +155,10 @@ static int qcom_cpufreq_kryo_probe(struct 
> platform_device *pdev)
>  
>       cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
>                                                         NULL, 0);
> -     if (!IS_ERR(cpufreq_dt_pdev))
> +     if (!IS_ERR(cpufreq_dt_pdev)) {
> +             platform_set_drvdata(pdev, opp_tables);
>               return 0;
> +     }
>  
>       ret = PTR_ERR(cpufreq_dt_pdev);
>       dev_err(cpu_dev, "Failed to register platform device\n");
> @@ -163,13 +169,23 @@ static int qcom_cpufreq_kryo_probe(struct 
> platform_device *pdev)
>                       break;
>               dev_pm_opp_put_supported_hw(opp_tables[cpu]);
>       }
> +     kfree(opp_tables);
>  
>       return ret;
>  }
>  
>  static int qcom_cpufreq_kryo_remove(struct platform_device *pdev)
>  {
> +     struct opp_table **opp_tables = platform_get_drvdata(pdev);
> +     unsigned cpu;

Nit: unsigned int

> +
>       platform_device_unregister(cpufreq_dt_pdev);
> +
> +     for_each_possible_cpu(cpu)
> +             dev_pm_opp_put_supported_hw(opp_tables[cpu]);
> +
> +     kfree(opp_tables);
> +
>       return 0;
>  }
>  

Reviewed-by: Georgi Djakov <georgi.dja...@linaro.org>

Thanks,
Georgi