Re: [PATCH V3 4/4] soc/tegra: pmc: Register PMC child devices as platform device

From: Jon Hunter
Date: Thu May 05 2016 - 06:15:26 EST



On 04/05/16 12:39, Laxman Dewangan wrote:
> Power Management Controller(PMC) of Tegra does the multiple chip
> power related functionality for internal and IO interfacing.
> Some of the functionalities are power gating of IP blocks, IO pads
> voltage and power state configuration, system power state configurations,
> wakeup controls etc.
>
> Different functionalities of the PMC are provided through different
> framework like IO pads control can be provided through pinctrl framework,
> IO power control is via misc driver etc. All sub functionalities are
> represented as PMC child devices.
>
> Register the PMC child devices as platform device and fill the child
> devices table for Tegra124 and Tegra210.
>
> Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>
>
> ---
> Changes from V1:
> Reworked on DT for having flat entry and register all child devices
> as simple platform device instead of of_populate_device().
>
> Changes from V2:
> - Handling of the release of child devices on error.
> - Register sub devices for T124 and T210 as T124 supports the DPD of IO
> pads.
> ---
> drivers/soc/tegra/pmc.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 80 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> index 0611cea..0eb652f 100644
> --- a/drivers/soc/tegra/pmc.c
> +++ b/drivers/soc/tegra/pmc.c
> @@ -132,6 +132,8 @@ struct tegra_pmc_soc {
> const u8 *cpu_powergates;
> const struct tegra_io_pads_control *io_pads_control;
> unsigned int num_io_pads;
> + const char **sub_devs_name;
> + unsigned int num_sub_devs;
> bool has_tsense_reset;
> bool has_gpu_clamps;
> };
> @@ -158,6 +160,7 @@ struct tegra_pmc_soc {
> * @lp0_vec_size: size of the LP0 warm boot code
> * @powergates_available: Bitmap of available power gates
> * @powergates_lock: mutex for power gate register access
> + * @pdevs: Platform device for PMC child devices.
> */
> struct tegra_pmc {
> struct device *dev;
> @@ -184,6 +187,8 @@ struct tegra_pmc {
> DECLARE_BITMAP(powergates_available, TEGRA_POWERGATE_MAX);
>
> struct mutex powergates_lock;
> +
> + struct platform_device **pdevs;
> };
>
> static struct tegra_pmc *pmc = &(struct tegra_pmc) {
> @@ -1310,6 +1315,57 @@ out:
> of_node_put(np);
> }
>
> +static int tegra_pmc_init_sub_devs(struct tegra_pmc *pmc)
> +{
> + int ret, i;
> +
> + if (!pmc->soc->num_sub_devs)
> + return 0;
> +
> + pmc->pdevs = devm_kzalloc(pmc->dev, pmc->soc->num_sub_devs *
> + sizeof(**pmc->pdevs), GFP_KERNEL);
> + if (!pmc->pdevs)
> + return -ENOMEM;
> +
> + for (i = 0; i < pmc->soc->num_sub_devs; ++i) {
> + pmc->pdevs[i] = platform_device_register_data(pmc->dev,
> + pmc->soc->sub_devs_name[i],
> + 0, NULL, 0);
> + if (IS_ERR(pmc->pdevs[i])) {
> + ret = PTR_ERR(pmc->pdevs[i]);
> + dev_err(pmc->dev,
> + "Failed to register platform device for %s: %d\n",
> + pmc->soc->sub_devs_name[i], ret);
> + goto pdev_cleanups;
> + }
> + }
> +
> + return 0;
> +
> +pdev_cleanups:
> + while (--i >= 0) {
> + platform_device_unregister(pmc->pdevs[i]);
> + pmc->pdevs[i] = NULL;
> + }
> +
> + return ret;
> +}
> +
> +static void tegra_pmc_deinit_sub_devs(struct tegra_pmc *pmc)
> +{
> + int i;
> +
> + if (!pmc->soc->num_sub_devs || !pmc->pdevs)
> + return;
> +
> + for (i = 0; i < pmc->soc->num_sub_devs; ++i) {
> + if (pmc->pdevs[i]) {
> + platform_device_unregister(pmc->pdevs[i]);
> + pmc->pdevs[i] = NULL;
> + }
> + }
> +}
> +
> static int tegra_pmc_probe(struct platform_device *pdev)
> {
> void __iomem *base;
> @@ -1339,10 +1395,14 @@ static int tegra_pmc_probe(struct platform_device *pdev)
>
> tegra_pmc_init_tsense_reset(pmc);
>
> + err = tegra_pmc_init_sub_devs(pmc);
> + if (err < 0)
> + dev_warn(pmc->dev, "Failed to register sub devices: %d\n", err);
> +
> if (IS_ENABLED(CONFIG_DEBUG_FS)) {
> err = tegra_powergate_debugfs_init();
> if (err < 0)
> - return err;
> + goto cleanups;
> }
>
> err = register_restart_handler(&tegra_pmc_restart_handler);
> @@ -1350,7 +1410,7 @@ static int tegra_pmc_probe(struct platform_device *pdev)
> debugfs_remove(pmc->debugfs);
> dev_err(&pdev->dev, "unable to register restart handler, %d\n",
> err);
> - return err;
> + goto cleanups;
> }
>
> tegra_powergate_init(pmc);
> @@ -1361,6 +1421,11 @@ static int tegra_pmc_probe(struct platform_device *pdev)
> mutex_unlock(&pmc->powergates_lock);
>
> return 0;
> +
> +cleanups:
> + tegra_pmc_deinit_sub_devs(pmc);
> +
> + return err;
> }
>
> #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_ARM)
> @@ -1544,6 +1609,10 @@ struct tegra_io_pads_control tegra124_io_pads_control[] = {
> TEGRA_IO_PADS_CONTROL(SYS_DDC, 58, -1),
> };
>
> +static const char *tegra124_sub_devs_name[] = {
> + "pinctrl-tegra124-io-pad",
> +};
> +
> static const struct tegra_pmc_soc tegra124_pmc_soc = {
> .num_powergates = ARRAY_SIZE(tegra124_powergates),
> .powergates = tegra124_powergates,
> @@ -1551,6 +1620,8 @@ static const struct tegra_pmc_soc tegra124_pmc_soc = {
> .cpu_powergates = tegra124_cpu_powergates,
> .io_pads_control = tegra124_io_pads_control,
> .num_io_pads = ARRAY_SIZE(tegra124_io_pads_control),
> + .sub_devs_name = tegra124_sub_devs_name,
> + .num_sub_devs = ARRAY_SIZE(tegra124_sub_devs_name),
> .has_tsense_reset = true,
> .has_gpu_clamps = true,
> };
> @@ -1628,6 +1699,11 @@ struct tegra_io_pads_control tegra210_io_pads_control[] = {
> TEGRA_IO_PADS_CONTROL(LVDS, 57, -1),
> TEGRA_IO_PADS_CONTROL(AUDIO_HV, 61, 18),
> };
> +
> +static const char *tegra210_sub_devs_name[] = {
> + "pinctrl-tegra210-io-pad",
> +};
> +
> static const struct tegra_pmc_soc tegra210_pmc_soc = {
> .num_powergates = ARRAY_SIZE(tegra210_powergates),
> .powergates = tegra210_powergates,
> @@ -1635,6 +1711,8 @@ static const struct tegra_pmc_soc tegra210_pmc_soc = {
> .cpu_powergates = tegra210_cpu_powergates,
> .io_pads_control = tegra210_io_pads_control,
> .num_io_pads = ARRAY_SIZE(tegra210_io_pads_control),
> + .sub_devs_name = tegra210_sub_devs_name,
> + .num_sub_devs = ARRAY_SIZE(tegra210_sub_devs_name),
> .has_tsense_reset = true,
> .has_gpu_clamps = true,
> };

I don't think that it makes sense to include this in this series. This
should be with the pinctrl driver.

Jon