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authorJakub Kicinski <kuba@kernel.org>2021-08-13 06:41:22 -0700
committerJakub Kicinski <kuba@kernel.org>2021-08-13 06:41:22 -0700
commitf4083a752a3b7dc2076432129c8469d02c25318e (patch)
tree6518d6c858a630508466906e30683d60bbef9748 /drivers/platform/x86/dual_accel_detect.h
parentb769cf44ed55f4b277b89cf53df6092f0c9082d0 (diff)
parentf8e6dfc64f6135d1b6c5215c14cd30b9b60a0008 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h 9e26680733d5 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp") 9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins") 099fdeda659d ("bnxt_en: Event handler for PPS events") kernel/bpf/helpers.c include/linux/bpf-cgroup.h a2baf4e8bb0f ("bpf: Fix potentially incorrect results with bpf_get_local_storage()") c7603cfa04e7 ("bpf: Add ambient BPF runtime context stored in current") drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c 5957cc557dc5 ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray") 2d0b41a37679 ("net/mlx5: Refcount mlx5_irq with integer") MAINTAINERS 7b637cd52f02 ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo") 7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/platform/x86/dual_accel_detect.h')
-rw-r--r--drivers/platform/x86/dual_accel_detect.h76
1 files changed, 76 insertions, 0 deletions
diff --git a/drivers/platform/x86/dual_accel_detect.h b/drivers/platform/x86/dual_accel_detect.h
new file mode 100644
index 000000000000..a9eae17cc43d
--- /dev/null
+++ b/drivers/platform/x86/dual_accel_detect.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Helper code to detect 360 degree hinges (yoga) style 2-in-1 devices using 2 accelerometers
+ * to allow the OS to determine the angle between the display and the base of the device.
+ *
+ * On Windows these are read by a special HingeAngleService process which calls undocumented
+ * ACPI methods, to let the firmware know if the 2-in-1 is in tablet- or laptop-mode.
+ * The firmware may use this to disable the kbd and touchpad to avoid spurious input in
+ * tablet-mode as well as to report SW_TABLET_MODE info to the OS.
+ *
+ * Since Linux does not call these undocumented methods, the SW_TABLET_MODE info reported
+ * by various drivers/platform/x86 drivers is incorrect. These drivers use the detection
+ * code in this file to disable SW_TABLET_MODE reporting to avoid reporting broken info
+ * (instead userspace can derive the status itself by directly reading the 2 accels).
+ */
+
+#include <linux/acpi.h>
+#include <linux/i2c.h>
+
+static int dual_accel_i2c_resource_count(struct acpi_resource *ares, void *data)
+{
+ struct acpi_resource_i2c_serialbus *sb;
+ int *count = data;
+
+ if (i2c_acpi_get_i2c_resource(ares, &sb))
+ *count = *count + 1;
+
+ return 1;
+}
+
+static int dual_accel_i2c_client_count(struct acpi_device *adev)
+{
+ int ret, count = 0;
+ LIST_HEAD(r);
+
+ ret = acpi_dev_get_resources(adev, &r, dual_accel_i2c_resource_count, &count);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&r);
+ return count;
+}
+
+static bool dual_accel_detect_bosc0200(void)
+{
+ struct acpi_device *adev;
+ int count;
+
+ adev = acpi_dev_get_first_match_dev("BOSC0200", NULL, -1);
+ if (!adev)
+ return false;
+
+ count = dual_accel_i2c_client_count(adev);
+
+ acpi_dev_put(adev);
+
+ return count == 2;
+}
+
+static bool dual_accel_detect(void)
+{
+ /* Systems which use a pair of accels with KIOX010A / KIOX020A ACPI ids */
+ if (acpi_dev_present("KIOX010A", NULL, -1) &&
+ acpi_dev_present("KIOX020A", NULL, -1))
+ return true;
+
+ /* Systems which use a single DUAL250E ACPI device to model 2 accels */
+ if (acpi_dev_present("DUAL250E", NULL, -1))
+ return true;
+
+ /* Systems which use a single BOSC0200 ACPI device to model 2 accels */
+ if (dual_accel_detect_bosc0200())
+ return true;
+
+ return false;
+}