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

From: Kai-Heng Feng
Date: Fri Apr 30 2021 - 02:07:59 EST


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>
---
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
--
2.30.2