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authorLinus Torvalds <torvalds@linux-foundation.org>2024-02-22 22:47:07 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2024-02-22 22:47:07 +0300
commitc7138f7a354df7cadccda31173617a7f30c8b6c6 (patch)
tree046e0c09544735df6ee80d9e8c68d118429b9fc0 /drivers/platform/x86/serdev_helpers.h
parent88953761b94df7dc9bfc46591a8975401689b057 (diff)
parent427c70dec738318b7f71e1b9d829ff0e9771d493 (diff)
downloadlinux-c7138f7a354df7cadccda31173617a7f30c8b6c6.tar.xz
Merge tag 'platform-drivers-x86-v6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver fixes from Hans de Goede: "Regression fixes: - Fix INT0002 vGPIO events no longer working after 6.8 ACPI SCI changes - AMD-PMF: Fix laptops (e.g. Framework 13 AMD) hanging on suspend - x86-android-tablets: Fix touchscreen no longer working on Lenovo Yogabook - x86-android-tablets: Fix serdev instantiation regression - intel-vbtn: Fix ThinkPad X1 Tablet Gen2 no longer suspending Bug fixes: - think-lmi: Fix changing BIOS settings on Lenovo workstations - touchscreen_dmi: Fix Hi8 Air touchscreen data sometimes missing - AMD-PMF: Fix Smart PC support not working after suspend/resume Other misc small fixes" * tag 'platform-drivers-x86-v6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: platform/x86: thinkpad_acpi: Only update profile if successfully converted platform/x86: intel-vbtn: Stop calling "VBDL" from notify_handler platform/x86: x86-android-tablets: Fix acer_b1_750_goodix_gpios name platform/x86: x86-android-tablets: Fix serdev instantiation no longer working platform/x86: Add new get_serdev_controller() helper platform/x86: x86-android-tablets: Fix keyboard touchscreen on Lenovo Yogabook1 X90 platform/x86/amd/pmf: Fix a potential race with policy binary sideload platform/x86/amd/pmf: Fixup error handling for amd_pmf_init_smart_pc() platform/x86/amd/pmf: Add debugging message for missing policy data platform/x86/amd/pmf: Fix a suspend hang on Framework 13 platform/x86/amd/pmf: Fix TEE enact command failure after suspend and resume platform/x86/amd/pmf: Remove smart_pc_status enum platform/x86: touchscreen_dmi: Consolidate Goodix upside-down touchscreen data platform/x86: touchscreen_dmi: Allow partial (prefix) matches for ACPI names platform/x86: intel: int0002_vgpio: Pass IRQF_ONESHOT to request_irq() platform/x86: think-lmi: Fix password opcode ordering for workstations
Diffstat (limited to 'drivers/platform/x86/serdev_helpers.h')
-rw-r--r--drivers/platform/x86/serdev_helpers.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/platform/x86/serdev_helpers.h b/drivers/platform/x86/serdev_helpers.h
new file mode 100644
index 000000000000..bcf3a0c356ea
--- /dev/null
+++ b/drivers/platform/x86/serdev_helpers.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * In some cases UART attached devices which require an in kernel driver,
+ * e.g. UART attached Bluetooth HCIs are described in the ACPI tables
+ * by an ACPI device with a broken or missing UartSerialBusV2() resource.
+ *
+ * This causes the kernel to create a /dev/ttyS# char-device for the UART
+ * instead of creating an in kernel serdev-controller + serdev-device pair
+ * for the in kernel driver.
+ *
+ * The quirk handling in acpi_quirk_skip_serdev_enumeration() makes the kernel
+ * create a serdev-controller device for these UARTs instead of a /dev/ttyS#.
+ *
+ * Instantiating the actual serdev-device to bind to is up to pdx86 code,
+ * this header provides a helper for getting the serdev-controller device.
+ */
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/printk.h>
+#include <linux/sprintf.h>
+#include <linux/string.h>
+
+static inline struct device *
+get_serdev_controller(const char *serial_ctrl_hid,
+ const char *serial_ctrl_uid,
+ int serial_ctrl_port,
+ const char *serdev_ctrl_name)
+{
+ struct device *ctrl_dev, *child;
+ struct acpi_device *ctrl_adev;
+ char name[32];
+ int i;
+
+ ctrl_adev = acpi_dev_get_first_match_dev(serial_ctrl_hid, serial_ctrl_uid, -1);
+ if (!ctrl_adev) {
+ pr_err("error could not get %s/%s serial-ctrl adev\n",
+ serial_ctrl_hid, serial_ctrl_uid);
+ return ERR_PTR(-ENODEV);
+ }
+
+ /* get_first_physical_node() returns a weak ref */
+ ctrl_dev = get_device(acpi_get_first_physical_node(ctrl_adev));
+ if (!ctrl_dev) {
+ pr_err("error could not get %s/%s serial-ctrl physical node\n",
+ serial_ctrl_hid, serial_ctrl_uid);
+ ctrl_dev = ERR_PTR(-ENODEV);
+ goto put_ctrl_adev;
+ }
+
+ /* Walk host -> uart-ctrl -> port -> serdev-ctrl */
+ for (i = 0; i < 3; i++) {
+ switch (i) {
+ case 0:
+ snprintf(name, sizeof(name), "%s:0", dev_name(ctrl_dev));
+ break;
+ case 1:
+ snprintf(name, sizeof(name), "%s.%d",
+ dev_name(ctrl_dev), serial_ctrl_port);
+ break;
+ case 2:
+ strscpy(name, serdev_ctrl_name, sizeof(name));
+ break;
+ }
+
+ child = device_find_child_by_name(ctrl_dev, name);
+ put_device(ctrl_dev);
+ if (!child) {
+ pr_err("error could not find '%s' device\n", name);
+ ctrl_dev = ERR_PTR(-ENODEV);
+ goto put_ctrl_adev;
+ }
+
+ ctrl_dev = child;
+ }
+
+put_ctrl_adev:
+ acpi_dev_put(ctrl_adev);
+ return ctrl_dev;
+}