Re: [PATCH] cpufreq: kryo: Add module remove and exit

From: Viresh Kumar
Date: Fri Jun 08 2018 - 00:29:27 EST


On 07-06-18, 20:58, ilia.lin@xxxxxxxxx wrote:
> From: Ilia Lin <ilia.lin@xxxxxxxxx>
>
> Add device remove and module exit code to make the driver
> functioning as a loadable module.
>
> Fixes: ac28927659be (cpufreq: kryo: allow building as a loadable module)
> Signed-off-by: Ilia Lin <ilia.lin@xxxxxxxxx>
> ---
> drivers/cpufreq/qcom-cpufreq-kryo.c | 24 +++++++++++++++++++++---
> 1 file changed, 21 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c
> index d049fe4b80c4..a08de0253169 100644
> --- a/drivers/cpufreq/qcom-cpufreq-kryo.c
> +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c
> @@ -71,10 +71,10 @@ static enum _msm8996_version __init qcom_cpufreq_kryo_get_msm_id(void)
> return version;
> }
>
> +struct platform_device *cpufreq_dt_pdev;

Move this and the other platform device pointer at the top of the file after the
enum declarations. They don't look nice in the middle of nowhere.

> static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
> {
> struct opp_table *opp_tables[NR_CPUS] = {0};
> - struct platform_device *cpufreq_dt_pdev;
> enum _msm8996_version msm8996_version;
> struct nvmem_cell *speedbin_nvmem;
> struct device_node *np;
> @@ -115,6 +115,8 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
>
> speedbin = nvmem_cell_read(speedbin_nvmem, &len);
> nvmem_cell_put(speedbin_nvmem);
> + if (IS_ERR(speedbin))
> + return PTR_ERR(speedbin);

This doesn't look related to this patch. Should it be a different commit ?

And I just saw definition of nvmem_cell_read() and it says the returned buffer
must be freed by caller using kfree(). I dont' see you doing that. Please also
check if any other such resources are there which you forgot to free.

>
> switch (msm8996_version) {
> case MSM8996_V3:
> @@ -162,8 +164,15 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
> return ret;
> }
>
> +static int qcom_cpufreq_kryo_remove(struct platform_device *pdev)
> +{
> + platform_device_unregister(cpufreq_dt_pdev);
> + return 0;
> +}
> +
> static struct platform_driver qcom_cpufreq_kryo_driver = {
> .probe = qcom_cpufreq_kryo_probe,
> + .remove = qcom_cpufreq_kryo_remove,
> .driver = {
> .name = "qcom-cpufreq-kryo",
> },
> @@ -174,6 +183,7 @@ static const struct of_device_id qcom_cpufreq_kryo_match_list[] __initconst = {
> { .compatible = "qcom,msm8996", },
> };
>
> +struct platform_device *kryo_cpufreq_pdev;
> /*
> * Since the driver depends on smem and nvmem drivers, which may
> * return EPROBE_DEFER, all the real activity is done in the probe,
> @@ -198,8 +208,9 @@ static int __init qcom_cpufreq_kryo_init(void)
> if (unlikely(ret < 0))
> return ret;
>
> - ret = PTR_ERR_OR_ZERO(platform_device_register_simple(
> - "qcom-cpufreq-kryo", -1, NULL, 0));
> + kryo_cpufreq_pdev = platform_device_register_simple(
> + "qcom-cpufreq-kryo", -1, NULL, 0);
> + ret = PTR_ERR_OR_ZERO(kryo_cpufreq_pdev);
> if (0 == ret)
> return 0;
>
> @@ -208,5 +219,12 @@ static int __init qcom_cpufreq_kryo_init(void)
> }
> module_init(qcom_cpufreq_kryo_init);
>
> +static void __init qcom_cpufreq_kryo_exit(void)
> +{
> + platform_device_unregister(kryo_cpufreq_pdev);
> + platform_driver_unregister(&qcom_cpufreq_kryo_driver);
> +}
> +module_exit(qcom_cpufreq_kryo_exit);
> +
> MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver");
> MODULE_LICENSE("GPL v2");

--
viresh