[PATCH] HID: i2c-hid: Refactor _DSM helper and add i2c-hid-acpi-prp0001 driver
From: 谢致邦 (XIE Zhibang)
Date: Thu Jun 04 2026 - 21:39:33 EST
Move the _DSM call that gets the HID descriptor address from
i2c-hid-acpi.c into i2c-hid-acpi.h as a static inline so both the ACPI
and the new PRP0001 driver can use it. While refactoring, move the
blacklist check and the _DSM call to the top of probe() to avoid a
pointless alloc when the device is blacklisted or does not implement the
_DSM.
Some devices, for example the Lenovo KaiTian N60d and Inspur CP300L3,
are declared with _HID "PRP0001" and _DSD compatible "hid-over-i2c" but
lack "hid-descr-addr" from the _DSD and provide the HID descriptor
address only through an ACPI _DSM. The OF driver fails to probe them
because it requires hid-descr-addr. Add a new driver that handles these
devices by calling the shared _DSM helper.
Fixes: b33752c30023 ("HID: i2c-hid: Reorganize so ACPI and OF are separate modules")
Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@xxxxxxxxx>
---
drivers/hid/i2c-hid/Kconfig | 18 +++++
drivers/hid/i2c-hid/Makefile | 1 +
drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c | 92 ++++++++++++++++++++++
drivers/hid/i2c-hid/i2c-hid-acpi.c | 48 +++--------
drivers/hid/i2c-hid/i2c-hid-acpi.h | 32 ++++++++
5 files changed, 155 insertions(+), 36 deletions(-)
create mode 100644 drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c
create mode 100644 drivers/hid/i2c-hid/i2c-hid-acpi.h
diff --git a/drivers/hid/i2c-hid/Kconfig b/drivers/hid/i2c-hid/Kconfig
index e8d51f410cc1..7db8b2abff78 100644
--- a/drivers/hid/i2c-hid/Kconfig
+++ b/drivers/hid/i2c-hid/Kconfig
@@ -22,6 +22,24 @@ config I2C_HID_ACPI
will be called i2c-hid-acpi. It will also build/depend on the
module i2c-hid.
+config I2C_HID_ACPI_PRP0001
+ tristate "Driver for PRP0001 devices missing hid-descr-addr"
+ depends on ACPI
+ depends on DRM || !DRM
+ select I2C_HID_CORE
+ help
+ Say Y here if you want support for I2C HID touchpads that
+ are declared with _HID "PRP0001" and _DSD compatible
+ "hid-over-i2c" but lack the "hid-descr-addr" property from
+ the _DSD. The HID descriptor address is instead provided
+ through an ACPI _DSM. Known affected devices include the
+ Lenovo KaiTian N60d and Inspur CP300L3.
+
+ If unsure, say N.
+
+ This support is also available as a module. If so, the
+ module will be called i2c-hid-acpi-prp0001.
+
config I2C_HID_OF
tristate "HID over I2C transport layer Open Firmware driver"
# No "depends on OF" because this can also be used for manually
diff --git a/drivers/hid/i2c-hid/Makefile b/drivers/hid/i2c-hid/Makefile
index 55bd5e0f35af..da420c1a8ec6 100644
--- a/drivers/hid/i2c-hid/Makefile
+++ b/drivers/hid/i2c-hid/Makefile
@@ -9,6 +9,7 @@ i2c-hid-objs = i2c-hid-core.o
i2c-hid-$(CONFIG_DMI) += i2c-hid-dmi-quirks.o
obj-$(CONFIG_I2C_HID_ACPI) += i2c-hid-acpi.o
+obj-$(CONFIG_I2C_HID_ACPI_PRP0001) += i2c-hid-acpi-prp0001.o
obj-$(CONFIG_I2C_HID_OF) += i2c-hid-of.o
obj-$(CONFIG_I2C_HID_OF_ELAN) += i2c-hid-of-elan.o
obj-$(CONFIG_I2C_HID_OF_GOODIX) += i2c-hid-of-goodix.o
diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c b/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c
new file mode 100644
index 000000000000..35cbbab347ac
--- /dev/null
+++ b/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * HID over I2C driver for PRP0001 devices missing hid-descr-addr
+ *
+ * Some devices, for example the Lenovo KaiTian N60d and Inspur CP300L3, use
+ * _HID "PRP0001" with _DSD compatible "hid-over-i2c" but lack "hid-descr-addr"
+ * from the _DSD. The HID descriptor address is provided only through an ACPI
+ * _DSM. The TPD0 node in the DSDT shows _DSM Function 1 returning 0x20.
+ *
+ * Copyright (C) 2026 谢致邦 (XIE Zhibang) <Yeking@xxxxxxxxx>
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include "i2c-hid.h"
+#include "i2c-hid-acpi.h"
+
+static int i2c_hid_acpi_prp0001_power_up(struct i2chid_ops *)
+{
+ /* give the device time to power up */
+ msleep(250);
+ return 0;
+}
+
+static struct i2chid_ops i2c_hid_acpi_prp0001_ops = {
+ .power_up = i2c_hid_acpi_prp0001_power_up,
+ /*
+ * No .restore_sequence needed: the _DSM on these devices returns a
+ * constant (0x20) with no side effects, unlike some PNP0C50 _DSM
+ * implementations that switch the hardware between PS/2 and I2C modes.
+ */
+};
+
+static int i2c_hid_acpi_prp0001_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct acpi_device *adev;
+ u16 hid_descriptor_address;
+ int ret;
+
+ /* If hid-descr-addr is present, let i2c-hid-of handle it */
+ if (device_property_present(dev, "hid-descr-addr"))
+ return -ENODEV;
+
+ adev = ACPI_COMPANION(dev);
+ if (!adev)
+ return -ENODEV;
+
+ ret = i2c_hid_acpi_get_descriptor(adev);
+ if (ret < 0)
+ return ret;
+ hid_descriptor_address = ret;
+
+ return i2c_hid_core_probe(client, &i2c_hid_acpi_prp0001_ops,
+ hid_descriptor_address, 0);
+}
+
+static const struct of_device_id i2c_hid_acpi_prp0001_of_match[] = {
+ { .compatible = "hid-over-i2c" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_hid_acpi_prp0001_of_match);
+
+static const struct i2c_device_id i2c_hid_acpi_prp0001_id[] = {
+ { .name = "hid-over-i2c" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, i2c_hid_acpi_prp0001_id);
+
+static struct i2c_driver i2c_hid_acpi_prp0001_driver = {
+ .driver = {
+ .name = "i2c_hid_acpi_prp0001",
+ .pm = &i2c_hid_core_pm,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ .of_match_table = of_match_ptr(i2c_hid_acpi_prp0001_of_match),
+ },
+
+ .probe = i2c_hid_acpi_prp0001_probe,
+ .remove = i2c_hid_core_remove,
+ .shutdown = i2c_hid_core_shutdown,
+ .id_table = i2c_hid_acpi_prp0001_id,
+};
+
+module_i2c_driver(i2c_hid_acpi_prp0001_driver);
+
+MODULE_DESCRIPTION("HID over I2C driver for PRP0001 devices missing hid-descr-addr");
+MODULE_AUTHOR("谢致邦 (XIE Zhibang) <Yeking@xxxxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi.c b/drivers/hid/i2c-hid/i2c-hid-acpi.c
index abd700a101f4..f0bcfb2663ef 100644
--- a/drivers/hid/i2c-hid/i2c-hid-acpi.c
+++ b/drivers/hid/i2c-hid/i2c-hid-acpi.c
@@ -25,9 +25,9 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pm.h>
-#include <linux/uuid.h>
#include "i2c-hid.h"
+#include "i2c-hid-acpi.h"
struct i2c_hid_acpi {
struct i2chid_ops ops;
@@ -48,39 +48,11 @@ static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
{ }
};
-/* HID I²C Device: 3cdff6f7-4267-4555-ad05-b30a3d8938de */
-static guid_t i2c_hid_guid =
- GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
- 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
-
-static int i2c_hid_acpi_get_descriptor(struct i2c_hid_acpi *ihid_acpi)
-{
- struct acpi_device *adev = ihid_acpi->adev;
- acpi_handle handle = acpi_device_handle(adev);
- union acpi_object *obj;
- u16 hid_descriptor_address;
-
- if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
- return -ENODEV;
-
- obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
- ACPI_TYPE_INTEGER);
- if (!obj) {
- acpi_handle_err(handle, "Error _DSM call to get HID descriptor address failed\n");
- return -ENODEV;
- }
-
- hid_descriptor_address = obj->integer.value;
- ACPI_FREE(obj);
-
- 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);
+ i2c_hid_acpi_get_descriptor(ihid_acpi->adev);
}
static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)
@@ -93,23 +65,27 @@ static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)
static int i2c_hid_acpi_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
+ struct acpi_device *adev = ACPI_COMPANION(dev);
struct i2c_hid_acpi *ihid_acpi;
u16 hid_descriptor_address;
int ret;
+ if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
+ return -ENODEV;
+
+ ret = i2c_hid_acpi_get_descriptor(adev);
+ if (ret < 0)
+ return ret;
+ hid_descriptor_address = ret;
+
ihid_acpi = devm_kzalloc(&client->dev, sizeof(*ihid_acpi), GFP_KERNEL);
if (!ihid_acpi)
return -ENOMEM;
- ihid_acpi->adev = ACPI_COMPANION(dev);
+ ihid_acpi->adev = adev;
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)
- return ret;
- hid_descriptor_address = ret;
-
acpi_device_fix_up_power(ihid_acpi->adev);
return i2c_hid_core_probe(client, &ihid_acpi->ops,
diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi.h b/drivers/hid/i2c-hid/i2c-hid-acpi.h
new file mode 100644
index 000000000000..8cebbeebcc23
--- /dev/null
+++ b/drivers/hid/i2c-hid/i2c-hid-acpi.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _I2C_HID_ACPI_H
+#define _I2C_HID_ACPI_H
+
+#include <linux/acpi.h>
+#include <linux/uuid.h>
+
+static inline int i2c_hid_acpi_get_descriptor(struct acpi_device *adev)
+{
+ /* HID I²C Device: 3cdff6f7-4267-4555-ad05-b30a3d8938de */
+ static const guid_t i2c_hid_guid =
+ GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
+ 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
+
+ acpi_handle handle = acpi_device_handle(adev);
+ union acpi_object *obj;
+ u16 addr;
+
+ obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid,
+ 1, 1, NULL, ACPI_TYPE_INTEGER);
+ if (!obj) {
+ acpi_handle_err(handle, "Error _DSM call to get HID descriptor address failed\n");
+ return -ENODEV;
+ }
+
+ addr = obj->integer.value;
+ ACPI_FREE(obj);
+ return addr;
+}
+
+#endif
--
2.54.0