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HID: i2c-hid: Resolve touchpad issues on Dell systems during S4

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Dell systems utilize an EC-based touchpad emulation when the ACPI
touchpad _DSM is not invoked. This emulation acts as a secondary
master on the I2C bus, designed for scenarios where the I2C touchpad
driver is absent, such as in BIOS menus. Typically, loading the
i2c-hid module triggers the _DSM at initialization, disabling the
EC-based emulation.

However, if the i2c-hid module is missing from the boot kernel
used for hibernation snapshot restoration, the _DSM remains
uncalled, resulting in dual masters on the I2C bus and
subsequent arbitration errors. This issue arises when i2c-hid
resides in the rootfs instead of the kernel or initramfs.

To address this, switch from using the SYSTEM_SLEEP_PM_OPS()
macro to dedicated callbacks, introducing a specific
callback for restoring the S4 image. This callback ensures
the _DSM is invoked.

Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
This commit is contained in:
Mario Limonciello (AMD) 2025-09-09 06:00:06 -05:00 committed by Benjamin Tissoires
parent 02d6eeedbc
commit 7d62beb102
3 changed files with 37 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/hid/i2c-hid/i2c-hid-acpi.c
View File

@ -76,6 +76,13 @@ static int i2c_hid_acpi_get_descriptor(struct i2c_hid_acpi *ihid_acpi)
return hid_descriptor_address;
}
static void i2c_hid_acpi_restore_sequence(struct i2chid_ops *ops)
{
struct i2c_hid_acpi *ihid_acpi = container_of(ops, struct i2c_hid_acpi, ops);
i2c_hid_acpi_get_descriptor(ihid_acpi);
}
static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)
{
struct i2c_hid_acpi *ihid_acpi = container_of(ops, struct i2c_hid_acpi, ops);
@ -96,6 +103,7 @@ static int i2c_hid_acpi_probe(struct i2c_client *client)
ihid_acpi->adev = ACPI_COMPANION(dev);
ihid_acpi->ops.shutdown_tail = i2c_hid_acpi_shutdown_tail;
ihid_acpi->ops.restore_sequence = i2c_hid_acpi_restore_sequence;
ret = i2c_hid_acpi_get_descriptor(ihid_acpi);
if (ret < 0)

28
drivers/hid/i2c-hid/i2c-hid-core.c
View File

@ -961,6 +961,14 @@ static void i2c_hid_core_shutdown_tail(struct i2c_hid *ihid)
ihid->ops->shutdown_tail(ihid->ops);
}
static void i2c_hid_core_restore_sequence(struct i2c_hid *ihid)
{
if (!ihid->ops->restore_sequence)
return;
ihid->ops->restore_sequence(ihid->ops);
}
static int i2c_hid_core_suspend(struct i2c_hid *ihid, bool force_poweroff)
{
struct i2c_client *client = ihid->client;
@ -1360,8 +1368,26 @@ static int i2c_hid_core_pm_resume(struct device *dev)
return i2c_hid_core_resume(ihid);
}
static int i2c_hid_core_pm_restore(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct i2c_hid *ihid = i2c_get_clientdata(client);
if (ihid->is_panel_follower)
return 0;
i2c_hid_core_restore_sequence(ihid);
return i2c_hid_core_resume(ihid);
}
const struct dev_pm_ops i2c_hid_core_pm = {
SYSTEM_SLEEP_PM_OPS(i2c_hid_core_pm_suspend, i2c_hid_core_pm_resume)
.suspend = pm_sleep_ptr(i2c_hid_core_pm_suspend),
.resume = pm_sleep_ptr(i2c_hid_core_pm_resume),
.freeze = pm_sleep_ptr(i2c_hid_core_pm_suspend),
.thaw = pm_sleep_ptr(i2c_hid_core_pm_resume),
.poweroff = pm_sleep_ptr(i2c_hid_core_pm_suspend),
.restore = pm_sleep_ptr(i2c_hid_core_pm_restore),
};
EXPORT_SYMBOL_GPL(i2c_hid_core_pm);

2
drivers/hid/i2c-hid/i2c-hid.h
View File

@ -27,11 +27,13 @@ static inline u32 i2c_hid_get_dmi_quirks(const u16 vendor, const u16 product)
* @power_up: do sequencing to power up the device.
* @power_down: do sequencing to power down the device.
* @shutdown_tail: called at the end of shutdown.
* @restore_sequence: hibernation restore sequence.
*/
struct i2chid_ops {
int (*power_up)(struct i2chid_ops *ops);
void (*power_down)(struct i2chid_ops *ops);
void (*shutdown_tail)(struct i2chid_ops *ops);
void (*restore_sequence)(struct i2chid_ops *ops);
};
int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,