[PATCH v3 0/3] HID: i2c-hid: Fix some PRP0001 touchpads probe after OF/ACPI split

[PATCH v3 0/3] HID: i2c-hid: Fix some PRP0001 touchpads probe after OF/ACPI split

[谢致邦 (XIE Zhibang)]

Before commit b33752c30023 ("HID: i2c-hid: Reorganize so ACPI and OF are
separate modules"), the unified i2c-hid driver handled both PNP0C50 ACPI
devices and hid-over-i2c OF devices. After the split, devices with _HID
"PRP0001" and _DSD compatible "hid-over-i2c" are only probed by
i2c_hid_of, which requires "hid-descr-addr" in the _DSD. Some devices,
for example the Lenovo KaiTian N60d and Inspur CP300L3, provide the HID
descriptor address only through the _DSM method and thus fail to probe.

Patch 1 moves the blacklist check so the function can return early
without wasting an allocation.

Patch 2 moves the _DSM call that gets the HID descriptor address from
i2c-hid-acpi.c to a shared helper in i2c-hid-core.c so both
i2c-hid-acpi.c and i2c-hid-of.c can use it.

Patch 3 calls the common helper as a fallback when "hid-descr-addr" is
missing, and sets safe post-power-on and post-reset-deassert delays.

谢致邦 (XIE Zhibang) (3):
  HID: i2c-hid-acpi: Move blacklist check to probe() before
    devm_kzalloc()
  HID: i2c-hid: Move common ACPI _DSM helper into core
  HID: i2c-hid-of: Fall back to ACPI _DSM when hid-descr-addr is missing

 drivers/hid/i2c-hid/i2c-hid-acpi.c | 41 +++++++-----------------------
 drivers/hid/i2c-hid/i2c-hid-core.c | 35 +++++++++++++++++++++++++
 drivers/hid/i2c-hid/i2c-hid-of.c   | 38 +++++++++++++++++++++++++++
 drivers/hid/i2c-hid/i2c-hid.h      | 11 ++++++++
 4 files changed, 93 insertions(+), 32 deletions(-)

-- 
2.43.0

[PATCH v3 1/3] HID: i2c-hid-acpi: Move blacklist check to probe() before devm_kzalloc()

[谢致邦 (XIE Zhibang)]

Move the check so the function can return early without wasting an
allocation. This is a pure refactoring, no functional change.

Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@Red54.com>
---
v2: Merge declaration into assignment.

 drivers/hid/i2c-hid/i2c-hid-acpi.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi.c b/drivers/hid/i2c-hid/i2c-hid-acpi.c
index abd700a101f4..f65fb6396b69 100644
--- a/drivers/hid/i2c-hid/i2c-hid-acpi.c
+++ b/drivers/hid/i2c-hid/i2c-hid-acpi.c
@@ -60,9 +60,6 @@ static int i2c_hid_acpi_get_descriptor(struct i2c_hid_acpi *ihid_acpi)
 	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) {
@@ -93,15 +90,19 @@ 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;
+
 	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;
 
-- 
2.43.0

[PATCH v3 2/3] HID: i2c-hid: Move common ACPI _DSM helper into core

[谢致邦 (XIE Zhibang)]

Move the _DSM call that gets the HID descriptor address from
i2c-hid-acpi.c to a shared helper in i2c-hid-core.c so both
i2c-hid-acpi.c and i2c-hid-of.c can use it.

Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@Red54.com>
---
 drivers/hid/i2c-hid/i2c-hid-acpi.c | 32 ++++-----------------------
 drivers/hid/i2c-hid/i2c-hid-core.c | 35 ++++++++++++++++++++++++++++++
 drivers/hid/i2c-hid/i2c-hid.h      | 11 ++++++++++
 3 files changed, 50 insertions(+), 28 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi.c b/drivers/hid/i2c-hid/i2c-hid-acpi.c
index f65fb6396b69..234789a07047 100644
--- a/drivers/hid/i2c-hid/i2c-hid-acpi.c
+++ b/drivers/hid/i2c-hid/i2c-hid-acpi.c
@@ -25,12 +25,12 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pm.h>
-#include <linux/uuid.h>
 
 #include "i2c-hid.h"
 
 struct i2c_hid_acpi {
 	struct i2chid_ops ops;
+	struct i2c_client *client;
 	struct acpi_device *adev;
 };
 
@@ -48,36 +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;
-
-	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_core_acpi_get_descriptor(&ihid_acpi->client->dev);
 }
 
 static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)
@@ -102,11 +77,12 @@ static int i2c_hid_acpi_probe(struct i2c_client *client)
 	if (!ihid_acpi)
 		return -ENOMEM;
 
+	ihid_acpi->client = client;
 	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);
+	ret = i2c_hid_core_acpi_get_descriptor(dev);
 	if (ret < 0)
 		return ret;
 	hid_descriptor_address = ret;
diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 3adb16366e93..1e1a8df5686d 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -1405,6 +1405,41 @@ const struct dev_pm_ops i2c_hid_core_pm = {
 };
 EXPORT_SYMBOL_GPL(i2c_hid_core_pm);
 
+#ifdef CONFIG_ACPI
+#include <linux/acpi.h>
+
+/* 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);
+
+int i2c_hid_core_acpi_get_descriptor(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	acpi_handle handle;
+	union acpi_object *obj;
+	u16 hid_descriptor_address;
+
+	if (!adev)
+		return -ENODEV;
+
+	handle = acpi_device_handle(adev);
+	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;
+}
+EXPORT_SYMBOL_GPL(i2c_hid_core_acpi_get_descriptor);
+#endif
+
 MODULE_DESCRIPTION("HID over I2C core driver");
 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
 MODULE_LICENSE("GPL");
diff --git a/drivers/hid/i2c-hid/i2c-hid.h b/drivers/hid/i2c-hid/i2c-hid.h
index 1724a435c783..bc8661c65b1a 100644
--- a/drivers/hid/i2c-hid/i2c-hid.h
+++ b/drivers/hid/i2c-hid/i2c-hid.h
@@ -44,4 +44,15 @@ void i2c_hid_core_shutdown(struct i2c_client *client);
 
 extern const struct dev_pm_ops i2c_hid_core_pm;
 
+#ifdef CONFIG_ACPI
+struct device;
+int i2c_hid_core_acpi_get_descriptor(struct device *dev);
+#else
+struct device;
+static inline int i2c_hid_core_acpi_get_descriptor(struct device *dev)
+{
+	return -ENODEV;
+}
+#endif
+
 #endif
-- 
2.43.0

[PATCH v3 3/3] HID: i2c-hid-of: Fall back to ACPI _DSM when hid-descr-addr is missing

[谢致邦 (XIE Zhibang)]

Before commit b33752c30023 ("HID: i2c-hid: Reorganize so ACPI and OF are
separate modules"), the unified i2c-hid driver handled both PNP0C50 ACPI
devices and hid-over-i2c OF devices. After the split, devices with _HID
"PRP0001" and _DSD compatible "hid-over-i2c" are only probed by
i2c_hid_of, which requires "hid-descr-addr" in the _DSD. Some devices,
for example the Lenovo KaiTian N60d and Inspur CP300L3, provide the HID
descriptor address only through the _DSM method. Call the common
i2c_hid_core_acpi_get_descriptor() helper as a fallback, and set safe
post-power-on and post-reset-deassert delays.

Fixes: b33752c30023 ("HID: i2c-hid: Reorganize so ACPI and OF are separate modules")
Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@Red54.com>
---
v3: Add restore_sequence

 drivers/hid/i2c-hid/i2c-hid-of.c | 38 ++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/hid/i2c-hid/i2c-hid-of.c b/drivers/hid/i2c-hid/i2c-hid-of.c
index 59393d71ddb9..325c64dfe81e 100644
--- a/drivers/hid/i2c-hid/i2c-hid-of.c
+++ b/drivers/hid/i2c-hid/i2c-hid-of.c
@@ -74,6 +74,13 @@ static void i2c_hid_of_power_down(struct i2chid_ops *ops)
 			       ihid_of->supplies);
 }
 
+static void i2c_hid_of_restore_sequence(struct i2chid_ops *ops)
+{
+	struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
+
+	i2c_hid_core_acpi_get_descriptor(&ihid_of->client->dev);
+}
+
 static int i2c_hid_of_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -92,6 +99,37 @@ static int i2c_hid_of_probe(struct i2c_client *client)
 	ihid_of->ops.power_down = i2c_hid_of_power_down;
 
 	ret = device_property_read_u32(dev, "hid-descr-addr", &val);
+	if (ret) {
+		/*
+		 * Some devices, for example the Lenovo KaiTian N60d and Inspur
+		 * CP300L3, declare their I2C HID touchpad with _HID "PRP0001"
+		 * and _DSD compatible "hid-over-i2c" but lack the
+		 * "hid-descr-addr" property. Fall back to _DSM to obtain the
+		 * HID descriptor address.
+		 */
+		int dsm_ret = i2c_hid_core_acpi_get_descriptor(dev);
+
+		if (dsm_ret >= 0) {
+			dev_warn(dev,
+				 "hid-descr-addr NOT found, using _DSM fallback. Contact vendor for firmware update!\n");
+			val = dsm_ret;
+
+			ihid_of->ops.restore_sequence = i2c_hid_of_restore_sequence;
+			/*
+			 * Firmware providing the descriptor address only
+			 * through _DSM may also lack "post-power-on-delay-ms"
+			 * or "post-reset-deassert-delay-ms", leaving the
+			 * driver without enough delay before the first HID
+			 * descriptor read. Set safe defaults to avoid reading
+			 * the descriptor before the device has finished its
+			 * internal power-on reset.
+			 */
+			ihid_of->post_power_delay_ms = 250;
+			ihid_of->post_reset_delay_ms = 250;
+
+			ret = 0;
+		}
+	}
 	if (ret) {
 		dev_err(dev, "HID register address not provided\n");
 		return -ENODEV;
-- 
2.43.0