Re: [PATCH 04/13] cpufreq: qcom: Refactor the driver to make it easier to extend

From: Ilia Lin
Date: Mon Jul 08 2019 - 02:31:11 EST


Reviewed-by: Ilia Lin <ilia.lin@xxxxxxxxxx>

On Fri, Jul 5, 2019 at 12:58 PM Niklas Cassel <niklas.cassel@xxxxxxxxxx> wrote:
>
> Refactor the driver to make it easier to extend in a later commit.
>
> Create a driver struct to collect all common resources, in order to make
> it easier to free up all common resources.
> Create a driver match_data struct to make it easier to extend the driver
> with support for new features that might only be supported on certain SoCs.
>
> Co-developed-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
> ---
> Changes since RFC:
> -Changed type of versions to u32 from u32*.
> -Make the driver use a match_data struct, so that different SoC can have
> different features.
> -Fixed error handling.
>
> drivers/cpufreq/qcom-cpufreq-nvmem.c | 123 +++++++++++++++++----------
> 1 file changed, 79 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> index fad6509eecb5..c0377b0eb2f4 100644
> --- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
> +++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> @@ -43,6 +43,20 @@ enum _msm8996_version {
> NUM_OF_MSM8996_VERSIONS,
> };
>
> +struct qcom_cpufreq_drv;
> +
> +struct qcom_cpufreq_match_data {
> + int (*get_version)(struct device *cpu_dev,
> + struct nvmem_cell *speedbin_nvmem,
> + struct qcom_cpufreq_drv *drv);
> +};
> +
> +struct qcom_cpufreq_drv {
> + struct opp_table **opp_tables;
> + u32 versions;
> + const struct qcom_cpufreq_match_data *data;
> +};
> +
> static struct platform_device *cpufreq_dt_pdev, *cpufreq_pdev;
>
> static enum _msm8996_version qcom_cpufreq_get_msm_id(void)
> @@ -76,7 +90,7 @@ static enum _msm8996_version qcom_cpufreq_get_msm_id(void)
>
> static int qcom_cpufreq_kryo_name_version(struct device *cpu_dev,
> struct nvmem_cell *speedbin_nvmem,
> - u32 *versions)
> + struct qcom_cpufreq_drv *drv)
> {
> size_t len;
> u8 *speedbin;
> @@ -94,10 +108,10 @@ static int qcom_cpufreq_kryo_name_version(struct device *cpu_dev,
>
> switch (msm8996_version) {
> case MSM8996_V3:
> - *versions = 1 << (unsigned int)(*speedbin);
> + drv->versions = 1 << (unsigned int)(*speedbin);
> break;
> case MSM8996_SG:
> - *versions = 1 << ((unsigned int)(*speedbin) + 4);
> + drv->versions = 1 << ((unsigned int)(*speedbin) + 4);
> break;
> default:
> BUG();
> @@ -108,17 +122,17 @@ static int qcom_cpufreq_kryo_name_version(struct device *cpu_dev,
> return 0;
> }
>
> +static const struct qcom_cpufreq_match_data match_data_kryo = {
> + .get_version = qcom_cpufreq_kryo_name_version,
> +};
> +
> static int qcom_cpufreq_probe(struct platform_device *pdev)
> {
> - struct opp_table **opp_tables;
> - int (*get_version)(struct device *cpu_dev,
> - struct nvmem_cell *speedbin_nvmem,
> - u32 *versions);
> + struct qcom_cpufreq_drv *drv;
> struct nvmem_cell *speedbin_nvmem;
> struct device_node *np;
> struct device *cpu_dev;
> unsigned cpu;
> - u32 versions;
> const struct of_device_id *match;
> int ret;
>
> @@ -126,11 +140,6 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
> if (!cpu_dev)
> return -ENODEV;
>
> - match = pdev->dev.platform_data;
> - get_version = match->data;
> - if (!get_version)
> - return -ENODEV;
> -
> np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
> if (!np)
> return -ENOENT;
> @@ -141,23 +150,43 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
> return -ENOENT;
> }
>
> - speedbin_nvmem = of_nvmem_cell_get(np, NULL);
> - of_node_put(np);
> - if (IS_ERR(speedbin_nvmem)) {
> - if (PTR_ERR(speedbin_nvmem) != -EPROBE_DEFER)
> - dev_err(cpu_dev, "Could not get nvmem cell: %ld\n",
> - PTR_ERR(speedbin_nvmem));
> - return PTR_ERR(speedbin_nvmem);
> + drv = kzalloc(sizeof(*drv), GFP_KERNEL);
> + if (!drv)
> + return -ENOMEM;
> +
> + match = pdev->dev.platform_data;
> + drv->data = match->data;
> + if (!drv->data) {
> + ret = -ENODEV;
> + goto free_drv;
> }
>
> - ret = get_version(cpu_dev, speedbin_nvmem, &versions);
> - nvmem_cell_put(speedbin_nvmem);
> - if (ret)
> - return ret;
> + if (drv->data->get_version) {
> + speedbin_nvmem = of_nvmem_cell_get(np, NULL);
> + of_node_put(np);
> + if (IS_ERR(speedbin_nvmem)) {
> + if (PTR_ERR(speedbin_nvmem) != -EPROBE_DEFER)
> + dev_err(cpu_dev,
> + "Could not get nvmem cell: %ld\n",
> + PTR_ERR(speedbin_nvmem));
> + ret = PTR_ERR(speedbin_nvmem);
> + goto free_drv;
> + }
>
> - opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables), GFP_KERNEL);
> - if (!opp_tables)
> - return -ENOMEM;
> + ret = drv->data->get_version(cpu_dev, speedbin_nvmem, drv);
> + if (ret) {
> + nvmem_cell_put(speedbin_nvmem);
> + goto free_drv;
> + }
> + nvmem_cell_put(speedbin_nvmem);
> + }
> +
> + drv->opp_tables = kcalloc(num_possible_cpus(), sizeof(*drv->opp_tables),
> + GFP_KERNEL);
> + if (!drv->opp_tables) {
> + ret = -ENOMEM;
> + goto free_drv;
> + }
>
> for_each_possible_cpu(cpu) {
> cpu_dev = get_cpu_device(cpu);
> @@ -166,19 +195,23 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
> goto free_opp;
> }
>
> - opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
> - &versions, 1);
> - if (IS_ERR(opp_tables[cpu])) {
> - ret = PTR_ERR(opp_tables[cpu]);
> - dev_err(cpu_dev, "Failed to set supported hardware\n");
> - goto free_opp;
> + if (drv->data->get_version) {
> + drv->opp_tables[cpu] =
> + dev_pm_opp_set_supported_hw(cpu_dev,
> + &drv->versions, 1);
> + if (IS_ERR(drv->opp_tables[cpu])) {
> + ret = PTR_ERR(drv->opp_tables[cpu]);
> + dev_err(cpu_dev,
> + "Failed to set supported hardware\n");
> + goto free_opp;
> + }
> }
> }
>
> cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
> NULL, 0);
> if (!IS_ERR(cpufreq_dt_pdev)) {
> - platform_set_drvdata(pdev, opp_tables);
> + platform_set_drvdata(pdev, drv);
> return 0;
> }
>
> @@ -187,26 +220,30 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
>
> free_opp:
> for_each_possible_cpu(cpu) {
> - if (IS_ERR_OR_NULL(opp_tables[cpu]))
> + if (IS_ERR_OR_NULL(drv->opp_tables[cpu]))
> break;
> - dev_pm_opp_put_supported_hw(opp_tables[cpu]);
> + dev_pm_opp_put_supported_hw(drv->opp_tables[cpu]);
> }
> - kfree(opp_tables);
> + kfree(drv->opp_tables);
> +free_drv:
> + kfree(drv);
>
> return ret;
> }
>
> static int qcom_cpufreq_remove(struct platform_device *pdev)
> {
> - struct opp_table **opp_tables = platform_get_drvdata(pdev);
> + struct qcom_cpufreq_drv *drv = platform_get_drvdata(pdev);
> unsigned int cpu;
>
> platform_device_unregister(cpufreq_dt_pdev);
>
> for_each_possible_cpu(cpu)
> - dev_pm_opp_put_supported_hw(opp_tables[cpu]);
> + if (drv->opp_tables[cpu])
> + dev_pm_opp_put_supported_hw(drv->opp_tables[cpu]);
>
> - kfree(opp_tables);
> + kfree(drv->opp_tables);
> + kfree(drv);
>
> return 0;
> }
> @@ -220,10 +257,8 @@ static struct platform_driver qcom_cpufreq_driver = {
> };
>
> static const struct of_device_id qcom_cpufreq_match_list[] __initconst = {
> - { .compatible = "qcom,apq8096",
> - .data = qcom_cpufreq_kryo_name_version },
> - { .compatible = "qcom,msm8996",
> - .data = qcom_cpufreq_kryo_name_version },
> + { .compatible = "qcom,apq8096", .data = &match_data_kryo },
> + { .compatible = "qcom,msm8996", .data = &match_data_kryo },
> {},
> };
>
> --
> 2.21.0
>