Re: [PATCH V4 02/18] pinctrl: tegra: add suspend and resume support

[Dmitry Osipenko]

24.06.2019 6:02, Sowjanya Komatineni ÐÐÑÐÑ:
> This patch adds support for Tegra pinctrl driver suspend and resume.
> 
> During suspend, context of all pinctrl registers are stored and
> on resume they are all restored to have all the pinmux and pad
> configuration for normal operation.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
> ---
>  drivers/pinctrl/tegra/pinctrl-tegra.c    | 47 ++++++++++++++++++++++++++++++++
>  drivers/pinctrl/tegra/pinctrl-tegra.h    |  4 +++
>  drivers/pinctrl/tegra/pinctrl-tegra210.c |  6 ++++
>  3 files changed, 57 insertions(+)
> 
> diff --git a/drivers/pinctrl/tegra/pinctrl-tegra.c b/drivers/pinctrl/tegra/pinctrl-tegra.c
> index b03c465917b8..c0ba6fa63ad1 100644
> --- a/drivers/pinctrl/tegra/pinctrl-tegra.c
> +++ b/drivers/pinctrl/tegra/pinctrl-tegra.c
> @@ -631,6 +631,38 @@ static void tegra_pinctrl_clear_parked_bits(struct tegra_pmx *pmx)
>  	}
>  }
>  
> +int __maybe_unused tegra_pinctrl_suspend(struct device *dev)

The "maybe_unused" attribute isn't needed for global functions because
compiler always assumes that such functions are used somewhere outside.

> +{
> +	struct tegra_pmx *pmx = dev_get_drvdata(dev);
> +	u32 *backup_regs = pmx->backup_regs;
> +	u32 *regs;
> +	unsigned int i, j;
> +
> +	for (i = 0; i < pmx->nbanks; i++) {
> +		regs = pmx->regs[i];
> +		for (j = 0; j < pmx->reg_bank_size[i] / 4; j++)
> +			*backup_regs++ = readl(regs++);
> +	}
> +
> +	return pinctrl_force_sleep(pmx->pctl);
> +}
> +
> +int __maybe_unused tegra_pinctrl_resume(struct device *dev)
> +{
> +	struct tegra_pmx *pmx = dev_get_drvdata(dev);
> +	u32 *backup_regs = pmx->backup_regs;
> +	u32 *regs;
> +	unsigned int i, j;
> +
> +	for (i = 0; i < pmx->nbanks; i++) {
> +		regs = pmx->regs[i];
> +		for (j = 0; j < pmx->reg_bank_size[i] / 4; j++)
> +			writel(*backup_regs++, regs++);
> +	}
> +
> +	return 0;
> +}
> +
>  static bool gpio_node_has_range(const char *compatible)
>  {
>  	struct device_node *np;
> @@ -655,6 +687,7 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
>  	int i;
>  	const char **group_pins;
>  	int fn, gn, gfn;
> +	unsigned long backup_regs_size = 0;
>  
>  	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
>  	if (!pmx)
> @@ -707,6 +740,7 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
>  		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
>  		if (!res)
>  			break;
> +		backup_regs_size += resource_size(res);
>  	}
>  	pmx->nbanks = i;
>  
> @@ -715,11 +749,24 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
>  	if (!pmx->regs)
>  		return -ENOMEM;
>  
> +	pmx->reg_bank_size = devm_kcalloc(&pdev->dev, pmx->nbanks,
> +					  sizeof(*pmx->reg_bank_size),
> +					  GFP_KERNEL);
> +	if (!pmx->reg_bank_size)
> +		return -ENOMEM;
> +
> +	pmx->backup_regs = devm_kzalloc(&pdev->dev, backup_regs_size,
> +					GFP_KERNEL);
> +	if (!pmx->backup_regs)
> +		return -ENOMEM;
> +
>  	for (i = 0; i < pmx->nbanks; i++) {
>  		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
>  		pmx->regs[i] = devm_ioremap_resource(&pdev->dev, res);
>  		if (IS_ERR(pmx->regs[i]))
>  			return PTR_ERR(pmx->regs[i]);
> +
> +		pmx->reg_bank_size[i] = resource_size(res);
>  	}
>  
>  	pmx->pctl = devm_pinctrl_register(&pdev->dev, &tegra_pinctrl_desc, pmx);
> diff --git a/drivers/pinctrl/tegra/pinctrl-tegra.h b/drivers/pinctrl/tegra/pinctrl-tegra.h
> index 32642af3f871..65fcbf8c7579 100644
> --- a/drivers/pinctrl/tegra/pinctrl-tegra.h
> +++ b/drivers/pinctrl/tegra/pinctrl-tegra.h
> @@ -17,6 +17,8 @@ struct tegra_pmx {
>  
>  	int nbanks;
>  	void __iomem **regs;
> +	size_t *reg_bank_size;
> +	u32 *backup_regs;
>  };
>  
>  enum tegra_pinconf_param {
> @@ -195,4 +197,6 @@ struct tegra_pinctrl_soc_data {
>  
>  int tegra_pinctrl_probe(struct platform_device *pdev,
>  			const struct tegra_pinctrl_soc_data *soc_data);
> +int __maybe_unused tegra_pinctrl_suspend(struct device *dev);
> +int __maybe_unused tegra_pinctrl_resume(struct device *dev);
>  #endif
> diff --git a/drivers/pinctrl/tegra/pinctrl-tegra210.c b/drivers/pinctrl/tegra/pinctrl-tegra210.c
> index 617ad963f5ad..4616bbc2efba 100644
> --- a/drivers/pinctrl/tegra/pinctrl-tegra210.c
> +++ b/drivers/pinctrl/tegra/pinctrl-tegra210.c
> @@ -1562,6 +1562,11 @@ static int tegra210_pinctrl_probe(struct platform_device *pdev)
>  	return tegra_pinctrl_probe(pdev, &tegra210_pinctrl);
>  }
>  
> +static const struct dev_pm_ops tegra_pinctrl_pm = {
> +	.suspend = &tegra_pinctrl_suspend,
> +	.resume = &tegra_pinctrl_resume
> +};

What about to move tegra_pinctrl_pm out into pinctrl-tegra.c to make it
common for all of the drivers?