Re: [PATCH 01/23] i2c: amd-mp2: Remove #ifdef guards for PM related functions

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Wed,  5 Jul 2023 22:42:52 +0200
Paul Cercueil <paul@crapouillou.net> wrote:

> Use the new PM macros for the suspend and resume functions to be
> automatically dropped by the compiler when CONFIG_PM or
> CONFIG_PM_SLEEP are disabled, without having to use #ifdef guards.
> 
> This has the advantage of always compiling these functions in,
> independently of any Kconfig option. Thanks to that, bugs and other
> regressions are subsequently easier to catch.
> 
> Note that the use of the UNIVERSAL_DEV_PM_OPS() macro was likely to be
> wrong, as it sets the same callbacks for the runtime-PM and system
> suspend/resume. This patch does not change this behaviour, but I suspect
> that it should be changed to use DEFINE_RUNTIME_DEV_PM_OPS() instead, as
> the current documentation for UNIVERSAL_DEV_PM_OPS() suggests.

I'd be tempted to leave this one alone because it'll be much harder
to spot that it's an ex UNIVERSAL_DEV_PM_OPS() that needs some thinking
about after this change.

> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> 
> ---
> Cc: Elie Morisse <syniurge@gmail.com>
> Cc: Shyam Sundar S K <shyam-sundar.s-k@amd.com>
> ---
>  drivers/i2c/busses/i2c-amd-mp2-pci.c  | 14 +++++---------
>  drivers/i2c/busses/i2c-amd-mp2-plat.c |  8 ++------
>  drivers/i2c/busses/i2c-amd-mp2.h      |  2 --
>  3 files changed, 7 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-amd-mp2-pci.c b/drivers/i2c/busses/i2c-amd-mp2-pci.c
> index 143165300949..114fe329279a 100644
> --- a/drivers/i2c/busses/i2c-amd-mp2-pci.c
> +++ b/drivers/i2c/busses/i2c-amd-mp2-pci.c
> @@ -382,7 +382,6 @@ static void amd_mp2_pci_remove(struct pci_dev *pci_dev)
>  	amd_mp2_clear_reg(privdata);
>  }
>  
> -#ifdef CONFIG_PM
>  static int amd_mp2_pci_suspend(struct device *dev)
>  {
>  	struct pci_dev *pci_dev = to_pci_dev(dev);
> @@ -434,9 +433,10 @@ static int amd_mp2_pci_resume(struct device *dev)
>  	return ret;
>  }
>  
> -static UNIVERSAL_DEV_PM_OPS(amd_mp2_pci_pm_ops, amd_mp2_pci_suspend,
> -			    amd_mp2_pci_resume, NULL);
> -#endif /* CONFIG_PM */
> +static const struct dev_pm_ops amd_mp2_pci_pm_ops = {
> +	SYSTEM_SLEEP_PM_OPS(amd_mp2_pci_suspend, amd_mp2_pci_resume)
> +	RUNTIME_PM_OPS(amd_mp2_pci_suspend, amd_mp2_pci_resume, NULL)
> +};
>  
>  static const struct pci_device_id amd_mp2_pci_tbl[] = {
>  	{PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)},
> @@ -449,11 +449,7 @@ static struct pci_driver amd_mp2_pci_driver = {
>  	.id_table	= amd_mp2_pci_tbl,
>  	.probe		= amd_mp2_pci_probe,
>  	.remove		= amd_mp2_pci_remove,
> -#ifdef CONFIG_PM
> -	.driver = {
> -		.pm	= &amd_mp2_pci_pm_ops,
> -	},
> -#endif
> +	.driver.pm	= pm_ptr(&amd_mp2_pci_pm_ops),
>  };
>  module_pci_driver(amd_mp2_pci_driver);
>  
> diff --git a/drivers/i2c/busses/i2c-amd-mp2-plat.c b/drivers/i2c/busses/i2c-amd-mp2-plat.c
> index 112fe2bc5662..4c677aeaca29 100644
> --- a/drivers/i2c/busses/i2c-amd-mp2-plat.c
> +++ b/drivers/i2c/busses/i2c-amd-mp2-plat.c
> @@ -183,7 +183,6 @@ static const struct i2c_algorithm i2c_amd_algorithm = {
>  	.functionality = i2c_amd_func,
>  };
>  
> -#ifdef CONFIG_PM
>  static int i2c_amd_suspend(struct amd_i2c_common *i2c_common)
>  {
>  	struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common);
> @@ -198,7 +197,6 @@ static int i2c_amd_resume(struct amd_i2c_common *i2c_common)
>  
>  	return i2c_amd_enable_set(i2c_dev, true);
>  }
> -#endif
>  
>  static const u32 supported_speeds[] = {
>  	I2C_MAX_HIGH_SPEED_MODE_FREQ,
> @@ -276,10 +274,8 @@ static int i2c_amd_probe(struct platform_device *pdev)
>  	platform_set_drvdata(pdev, i2c_dev);
>  
>  	i2c_dev->common.cmd_completion = &i2c_amd_cmd_completion;
> -#ifdef CONFIG_PM
> -	i2c_dev->common.suspend = &i2c_amd_suspend;
> -	i2c_dev->common.resume = &i2c_amd_resume;
> -#endif
> +	i2c_dev->common.suspend = pm_ptr(&i2c_amd_suspend);
> +	i2c_dev->common.resume = pm_ptr(&i2c_amd_resume);
>  
>  	/* Register the adapter */
>  	amd_mp2_pm_runtime_get(mp2_dev);
> diff --git a/drivers/i2c/busses/i2c-amd-mp2.h b/drivers/i2c/busses/i2c-amd-mp2.h
> index 018a42de8b1e..40f3cdcc60aa 100644
> --- a/drivers/i2c/busses/i2c-amd-mp2.h
> +++ b/drivers/i2c/busses/i2c-amd-mp2.h
> @@ -160,10 +160,8 @@ struct amd_i2c_common {
>  	enum speed_enum i2c_speed;
>  	u8 *dma_buf;
>  	dma_addr_t dma_addr;
> -#ifdef CONFIG_PM
>  	int (*suspend)(struct amd_i2c_common *i2c_common);
>  	int (*resume)(struct amd_i2c_common *i2c_common);
> -#endif /* CONFIG_PM */
>  };
>  
>  /**