Re: [PATCH] platform/x86: hp_accel: Avoid invoking _INI to speed up resume

[Hans de Goede]

Hi,

On 4/30/21 8:07 AM, Kai-Heng Feng wrote:
> hp_accel can take almost two seconds to resume on some HP laptops.
> 
> The bottleneck is on evaluating _INI, which is only needed to run once.
> 
> Resolve the issue by only invoking _INI when it's necessary. Namely, on
> probe and on hibernation restore.
> 
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>

Thank you I've added this to my review-hans branch.
I'll also add this to my fixes branch and include it in
a future pdx86 fixes pull-req for Linus for 5.13.

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans


> ---
>  drivers/misc/lis3lv02d/lis3lv02d.h |  1 +
>  drivers/platform/x86/hp_accel.c    | 22 +++++++++++++++++++++-
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/misc/lis3lv02d/lis3lv02d.h b/drivers/misc/lis3lv02d/lis3lv02d.h
> index c394c0b08519a..7ac788fae1b86 100644
> --- a/drivers/misc/lis3lv02d/lis3lv02d.h
> +++ b/drivers/misc/lis3lv02d/lis3lv02d.h
> @@ -271,6 +271,7 @@ struct lis3lv02d {
>  	int			regs_size;
>  	u8                      *reg_cache;
>  	bool			regs_stored;
> +	bool			init_required;
>  	u8                      odr_mask;  /* ODR bit mask */
>  	u8			whoami;    /* indicates measurement precision */
>  	s16 (*read_data) (struct lis3lv02d *lis3, int reg);
> diff --git a/drivers/platform/x86/hp_accel.c b/drivers/platform/x86/hp_accel.c
> index 799cbe2ffcf36..8c0867bda8280 100644
> --- a/drivers/platform/x86/hp_accel.c
> +++ b/drivers/platform/x86/hp_accel.c
> @@ -88,6 +88,9 @@ MODULE_DEVICE_TABLE(acpi, lis3lv02d_device_ids);
>  static int lis3lv02d_acpi_init(struct lis3lv02d *lis3)
>  {
>  	struct acpi_device *dev = lis3->bus_priv;
> +	if (!lis3->init_required)
> +		return 0;
> +
>  	if (acpi_evaluate_object(dev->handle, METHOD_NAME__INI,
>  				 NULL, NULL) != AE_OK)
>  		return -EINVAL;
> @@ -356,6 +359,7 @@ static int lis3lv02d_add(struct acpi_device *device)
>  	}
>  
>  	/* call the core layer do its init */
> +	lis3_dev.init_required = true;
>  	ret = lis3lv02d_init_device(&lis3_dev);
>  	if (ret)
>  		return ret;
> @@ -403,11 +407,27 @@ static int lis3lv02d_suspend(struct device *dev)
>  
>  static int lis3lv02d_resume(struct device *dev)
>  {
> +	lis3_dev.init_required = false;
> +	lis3lv02d_poweron(&lis3_dev);
> +	return 0;
> +}
> +
> +static int lis3lv02d_restore(struct device *dev)
> +{
> +	lis3_dev.init_required = true;
>  	lis3lv02d_poweron(&lis3_dev);
>  	return 0;
>  }
>  
> -static SIMPLE_DEV_PM_OPS(hp_accel_pm, lis3lv02d_suspend, lis3lv02d_resume);
> +static const struct dev_pm_ops hp_accel_pm = {
> +	.suspend = lis3lv02d_suspend,
> +	.resume = lis3lv02d_resume,
> +	.freeze = lis3lv02d_suspend,
> +	.thaw = lis3lv02d_resume,
> +	.poweroff = lis3lv02d_suspend,
> +	.restore = lis3lv02d_restore,
> +};
> +
>  #define HP_ACCEL_PM (&hp_accel_pm)
>  #else
>  #define HP_ACCEL_PM NULL
>