diff --git a/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw b/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw new file mode 100644 index 000000000000..74cd9d754e60 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw @@ -0,0 +1,57 @@ +What: /sys/bus/surface_aggregator/devices/01:0e:01:00:01/state +Date: July 2022 +KernelVersion: 5.20 +Contact: Maximilian Luz +Description: + This attribute returns a string with the current type-cover + or device posture, as indicated by the embedded controller. + Currently returned posture states are: + + - "disconnected": The type-cover has been disconnected. + + - "closed": The type-cover has been folded closed and lies on + top of the display. + + - "laptop": The type-cover is open and in laptop-mode, i.e., + ready for normal use. + + - "folded-canvas": The type-cover has been folded back + part-ways, but does not lie flush with the back side of the + device. In general, this means that the kick-stand is used + and extended atop of the cover. + + - "folded-back": The type cover has been fully folded back and + lies flush with the back side of the device. + + - "": The current state is unknown to the driver, for + example due to newer as-of-yet unsupported hardware. + + New states may be introduced with new hardware. Users therefore + must not rely on this list of states being exhaustive and + gracefully handle unknown states. + +What: /sys/bus/surface_aggregator/devices/01:26:01:00:01/state +Date: July 2022 +KernelVersion: 5.20 +Contact: Maximilian Luz +Description: + This attribute returns a string with the current device posture, as indicated by the embedded controller. Currently + returned posture states are: + + - "closed": The lid of the device is closed. + + - "laptop": The lid of the device is opened and the device + operates as a normal laptop. + + - "slate": The screen covers the keyboard or has been flipped + back and the device operates mainly based on touch input. + + - "tablet": The device operates as tablet and exclusively + relies on touch input (or external peripherals). + + - "": The current state is unknown to the driver, for + example due to newer as-of-yet unsupported hardware. + + New states may be introduced with new hardware. Users therefore + must not rely on this list of states being exhaustive and + gracefully handle unknown states. diff --git a/MAINTAINERS b/MAINTAINERS index 2a34deb24594..c6d8c0c6bf6e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13176,6 +13176,12 @@ F: drivers/scsi/smartpqi/smartpqi*.[ch] F: include/linux/cciss*.h F: include/uapi/linux/cciss*.h +MICROSOFT SURFACE AGGREGATOR TABLET-MODE SWITCH +M: Maximilian Luz +L: platform-driver-x86@vger.kernel.org +S: Maintained +F: drivers/platform/surface/surface_aggregator_tablet_switch.c + MICROSOFT SURFACE BATTERY AND AC DRIVERS M: Maximilian Luz L: linux-pm@vger.kernel.org diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig index eb79fbed8059..b152e930cc84 100644 --- a/drivers/platform/surface/Kconfig +++ b/drivers/platform/surface/Kconfig @@ -99,6 +99,29 @@ config SURFACE_AGGREGATOR_REGISTRY the respective client devices. Drivers for these devices still need to be selected via the other options. +config SURFACE_AGGREGATOR_TABLET_SWITCH + tristate "Surface Aggregator Generic Tablet-Mode Switch Driver" + depends on SURFACE_AGGREGATOR + depends on SURFACE_AGGREGATOR_BUS + depends on INPUT + help + Provides a tablet-mode switch input device on Microsoft Surface models + using the KIP subsystem for detachable keyboards (e.g. keyboard covers) + or the POS subsystem for device/screen posture changes. + + The KIP subsystem is used on newer Surface generations to handle + detachable input peripherals, specifically the keyboard cover (containing + keyboard and touchpad) on the Surface Pro 8 and Surface Pro X. The POS + subsystem is used for device posture change notifications on the Surface + Laptop Studio. This module provides a driver to let user-space know when + the device should be considered in tablet-mode due to the keyboard cover + being detached or folded back (essentially signaling when the keyboard is + not available for input). It does so by creating a tablet-mode switch + input device, sending the standard SW_TABLET_MODE event on mode change. + + Select M or Y here, if you want to provide tablet-mode switch input + events on the Surface Pro 8, Surface Pro X, and Surface Laptop Studio. + config SURFACE_DTX tristate "Surface DTX (Detachment System) Driver" depends on SURFACE_AGGREGATOR diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile index 0fc9cd3e4dd9..18b27898543e 100644 --- a/drivers/platform/surface/Makefile +++ b/drivers/platform/surface/Makefile @@ -10,6 +10,7 @@ obj-$(CONFIG_SURFACE_ACPI_NOTIFY) += surface_acpi_notify.o obj-$(CONFIG_SURFACE_AGGREGATOR) += aggregator/ obj-$(CONFIG_SURFACE_AGGREGATOR_CDEV) += surface_aggregator_cdev.o obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o +obj-$(CONFIG_SURFACE_AGGREGATOR_TABLET_SWITCH) += surface_aggregator_tabletsw.o obj-$(CONFIG_SURFACE_DTX) += surface_dtx.o obj-$(CONFIG_SURFACE_GPE) += surface_gpe.o obj-$(CONFIG_SURFACE_HOTPLUG) += surface_hotplug.o diff --git a/drivers/platform/surface/surface_aggregator_tabletsw.c b/drivers/platform/surface/surface_aggregator_tabletsw.c new file mode 100644 index 000000000000..596ca6c80681 --- /dev/null +++ b/drivers/platform/surface/surface_aggregator_tabletsw.c @@ -0,0 +1,533 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Surface System Aggregator Module (SSAM) tablet mode switch driver. + * + * Copyright (C) 2022 Maximilian Luz + */ + +#include +#include +#include +#include +#include +#include + +#include +#include + + +/* -- SSAM generic tablet switch driver framework. -------------------------- */ + +struct ssam_tablet_sw; + +struct ssam_tablet_sw_ops { + int (*get_state)(struct ssam_tablet_sw *sw, u32 *state); + const char *(*state_name)(struct ssam_tablet_sw *sw, u32 state); + bool (*state_is_tablet_mode)(struct ssam_tablet_sw *sw, u32 state); +}; + +struct ssam_tablet_sw { + struct ssam_device *sdev; + + u32 state; + struct work_struct update_work; + struct input_dev *mode_switch; + + struct ssam_tablet_sw_ops ops; + struct ssam_event_notifier notif; +}; + +struct ssam_tablet_sw_desc { + struct { + const char *name; + const char *phys; + } dev; + + struct { + u32 (*notify)(struct ssam_event_notifier *nf, const struct ssam_event *event); + int (*get_state)(struct ssam_tablet_sw *sw, u32 *state); + const char *(*state_name)(struct ssam_tablet_sw *sw, u32 state); + bool (*state_is_tablet_mode)(struct ssam_tablet_sw *sw, u32 state); + } ops; + + struct { + struct ssam_event_registry reg; + struct ssam_event_id id; + enum ssam_event_mask mask; + u8 flags; + } event; +}; + +static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct ssam_tablet_sw *sw = dev_get_drvdata(dev); + const char *state = sw->ops.state_name(sw, sw->state); + + return sysfs_emit(buf, "%s\n", state); +} +static DEVICE_ATTR_RO(state); + +static struct attribute *ssam_tablet_sw_attrs[] = { + &dev_attr_state.attr, + NULL, +}; + +static const struct attribute_group ssam_tablet_sw_group = { + .attrs = ssam_tablet_sw_attrs, +}; + +static void ssam_tablet_sw_update_workfn(struct work_struct *work) +{ + struct ssam_tablet_sw *sw = container_of(work, struct ssam_tablet_sw, update_work); + int tablet, status; + u32 state; + + status = sw->ops.get_state(sw, &state); + if (status) + return; + + if (sw->state == state) + return; + sw->state = state; + + /* Send SW_TABLET_MODE event. */ + tablet = sw->ops.state_is_tablet_mode(sw, state); + input_report_switch(sw->mode_switch, SW_TABLET_MODE, tablet); + input_sync(sw->mode_switch); +} + +static int __maybe_unused ssam_tablet_sw_resume(struct device *dev) +{ + struct ssam_tablet_sw *sw = dev_get_drvdata(dev); + + schedule_work(&sw->update_work); + return 0; +} +static SIMPLE_DEV_PM_OPS(ssam_tablet_sw_pm_ops, NULL, ssam_tablet_sw_resume); + +static int ssam_tablet_sw_probe(struct ssam_device *sdev) +{ + const struct ssam_tablet_sw_desc *desc; + struct ssam_tablet_sw *sw; + int tablet, status; + + desc = ssam_device_get_match_data(sdev); + if (!desc) { + WARN(1, "no driver match data specified"); + return -EINVAL; + } + + sw = devm_kzalloc(&sdev->dev, sizeof(*sw), GFP_KERNEL); + if (!sw) + return -ENOMEM; + + sw->sdev = sdev; + + sw->ops.get_state = desc->ops.get_state; + sw->ops.state_name = desc->ops.state_name; + sw->ops.state_is_tablet_mode = desc->ops.state_is_tablet_mode; + + INIT_WORK(&sw->update_work, ssam_tablet_sw_update_workfn); + + ssam_device_set_drvdata(sdev, sw); + + /* Get initial state. */ + status = sw->ops.get_state(sw, &sw->state); + if (status) + return status; + + /* Set up tablet mode switch. */ + sw->mode_switch = devm_input_allocate_device(&sdev->dev); + if (!sw->mode_switch) + return -ENOMEM; + + sw->mode_switch->name = desc->dev.name; + sw->mode_switch->phys = desc->dev.phys; + sw->mode_switch->id.bustype = BUS_HOST; + sw->mode_switch->dev.parent = &sdev->dev; + + tablet = sw->ops.state_is_tablet_mode(sw, sw->state); + input_set_capability(sw->mode_switch, EV_SW, SW_TABLET_MODE); + input_report_switch(sw->mode_switch, SW_TABLET_MODE, tablet); + + status = input_register_device(sw->mode_switch); + if (status) + return status; + + /* Set up notifier. */ + sw->notif.base.priority = 0; + sw->notif.base.fn = desc->ops.notify; + sw->notif.event.reg = desc->event.reg; + sw->notif.event.id = desc->event.id; + sw->notif.event.mask = desc->event.mask; + sw->notif.event.flags = SSAM_EVENT_SEQUENCED; + + status = ssam_device_notifier_register(sdev, &sw->notif); + if (status) + return status; + + status = sysfs_create_group(&sdev->dev.kobj, &ssam_tablet_sw_group); + if (status) + goto err; + + /* We might have missed events during setup, so check again. */ + schedule_work(&sw->update_work); + return 0; + +err: + ssam_device_notifier_unregister(sdev, &sw->notif); + cancel_work_sync(&sw->update_work); + return status; +} + +static void ssam_tablet_sw_remove(struct ssam_device *sdev) +{ + struct ssam_tablet_sw *sw = ssam_device_get_drvdata(sdev); + + sysfs_remove_group(&sdev->dev.kobj, &ssam_tablet_sw_group); + + ssam_device_notifier_unregister(sdev, &sw->notif); + cancel_work_sync(&sw->update_work); +} + + +/* -- SSAM KIP tablet switch implementation. -------------------------------- */ + +#define SSAM_EVENT_KIP_CID_COVER_STATE_CHANGED 0x1d + +enum ssam_kip_cover_state { + SSAM_KIP_COVER_STATE_DISCONNECTED = 0x01, + SSAM_KIP_COVER_STATE_CLOSED = 0x02, + SSAM_KIP_COVER_STATE_LAPTOP = 0x03, + SSAM_KIP_COVER_STATE_FOLDED_CANVAS = 0x04, + SSAM_KIP_COVER_STATE_FOLDED_BACK = 0x05, +}; + +static const char *ssam_kip_cover_state_name(struct ssam_tablet_sw *sw, u32 state) +{ + switch (state) { + case SSAM_KIP_COVER_STATE_DISCONNECTED: + return "disconnected"; + + case SSAM_KIP_COVER_STATE_CLOSED: + return "closed"; + + case SSAM_KIP_COVER_STATE_LAPTOP: + return "laptop"; + + case SSAM_KIP_COVER_STATE_FOLDED_CANVAS: + return "folded-canvas"; + + case SSAM_KIP_COVER_STATE_FOLDED_BACK: + return "folded-back"; + + default: + dev_warn(&sw->sdev->dev, "unknown KIP cover state: %u\n", state); + return ""; + } +} + +static bool ssam_kip_cover_state_is_tablet_mode(struct ssam_tablet_sw *sw, u32 state) +{ + switch (state) { + case SSAM_KIP_COVER_STATE_DISCONNECTED: + case SSAM_KIP_COVER_STATE_FOLDED_CANVAS: + case SSAM_KIP_COVER_STATE_FOLDED_BACK: + return true; + + case SSAM_KIP_COVER_STATE_CLOSED: + case SSAM_KIP_COVER_STATE_LAPTOP: + return false; + + default: + dev_warn(&sw->sdev->dev, "unknown KIP cover state: %d\n", sw->state); + return true; + } +} + +SSAM_DEFINE_SYNC_REQUEST_R(__ssam_kip_get_cover_state, u8, { + .target_category = SSAM_SSH_TC_KIP, + .target_id = 0x01, + .command_id = 0x1d, + .instance_id = 0x00, +}); + +static int ssam_kip_get_cover_state(struct ssam_tablet_sw *sw, u32 *state) +{ + int status; + u8 raw; + + status = ssam_retry(__ssam_kip_get_cover_state, sw->sdev->ctrl, &raw); + if (status < 0) { + dev_err(&sw->sdev->dev, "failed to query KIP lid state: %d\n", status); + return status; + } + + *state = raw; + return 0; +} + +static u32 ssam_kip_sw_notif(struct ssam_event_notifier *nf, const struct ssam_event *event) +{ + struct ssam_tablet_sw *sw = container_of(nf, struct ssam_tablet_sw, notif); + + if (event->command_id != SSAM_EVENT_KIP_CID_COVER_STATE_CHANGED) + return 0; /* Return "unhandled". */ + + if (event->length < 1) + dev_warn(&sw->sdev->dev, "unexpected payload size: %u\n", event->length); + + schedule_work(&sw->update_work); + return SSAM_NOTIF_HANDLED; +} + +static const struct ssam_tablet_sw_desc ssam_kip_sw_desc = { + .dev = { + .name = "Microsoft Surface KIP Tablet Mode Switch", + .phys = "ssam/01:0e:01:00:01/input0", + }, + .ops = { + .notify = ssam_kip_sw_notif, + .get_state = ssam_kip_get_cover_state, + .state_name = ssam_kip_cover_state_name, + .state_is_tablet_mode = ssam_kip_cover_state_is_tablet_mode, + }, + .event = { + .reg = SSAM_EVENT_REGISTRY_SAM, + .id = { + .target_category = SSAM_SSH_TC_KIP, + .instance = 0, + }, + .mask = SSAM_EVENT_MASK_TARGET, + }, +}; + + +/* -- SSAM POS tablet switch implementation. -------------------------------- */ + +static bool tablet_mode_in_slate_state = true; +module_param(tablet_mode_in_slate_state, bool, 0644); +MODULE_PARM_DESC(tablet_mode_in_slate_state, "Enable tablet mode in slate device posture, default is 'true'"); + +#define SSAM_EVENT_POS_CID_POSTURE_CHANGED 0x03 +#define SSAM_POS_MAX_SOURCES 4 + +enum ssam_pos_state { + SSAM_POS_POSTURE_LID_CLOSED = 0x00, + SSAM_POS_POSTURE_LAPTOP = 0x01, + SSAM_POS_POSTURE_SLATE = 0x02, + SSAM_POS_POSTURE_TABLET = 0x03, +}; + +struct ssam_sources_list { + __le32 count; + __le32 id[SSAM_POS_MAX_SOURCES]; +} __packed; + +static const char *ssam_pos_state_name(struct ssam_tablet_sw *sw, u32 state) +{ + switch (state) { + case SSAM_POS_POSTURE_LID_CLOSED: + return "closed"; + + case SSAM_POS_POSTURE_LAPTOP: + return "laptop"; + + case SSAM_POS_POSTURE_SLATE: + return "slate"; + + case SSAM_POS_POSTURE_TABLET: + return "tablet"; + + default: + dev_warn(&sw->sdev->dev, "unknown device posture: %u\n", state); + return ""; + } +} + +static bool ssam_pos_state_is_tablet_mode(struct ssam_tablet_sw *sw, u32 state) +{ + switch (state) { + case SSAM_POS_POSTURE_LAPTOP: + case SSAM_POS_POSTURE_LID_CLOSED: + return false; + + case SSAM_POS_POSTURE_SLATE: + return tablet_mode_in_slate_state; + + case SSAM_POS_POSTURE_TABLET: + return true; + + default: + dev_warn(&sw->sdev->dev, "unknown device posture: %u\n", state); + return true; + } +} + +static int ssam_pos_get_sources_list(struct ssam_tablet_sw *sw, struct ssam_sources_list *sources) +{ + struct ssam_request rqst; + struct ssam_response rsp; + int status; + + rqst.target_category = SSAM_SSH_TC_POS; + rqst.target_id = 0x01; + rqst.command_id = 0x01; + rqst.instance_id = 0x00; + rqst.flags = SSAM_REQUEST_HAS_RESPONSE; + rqst.length = 0; + rqst.payload = NULL; + + rsp.capacity = sizeof(*sources); + rsp.length = 0; + rsp.pointer = (u8 *)sources; + + status = ssam_retry(ssam_request_sync_onstack, sw->sdev->ctrl, &rqst, &rsp, 0); + if (status) + return status; + + /* We need at least the 'sources->count' field. */ + if (rsp.length < sizeof(__le32)) { + dev_err(&sw->sdev->dev, "received source list response is too small\n"); + return -EPROTO; + } + + /* Make sure 'sources->count' matches with the response length. */ + if (get_unaligned_le32(&sources->count) * sizeof(__le32) + sizeof(__le32) != rsp.length) { + dev_err(&sw->sdev->dev, "mismatch between number of sources and response size\n"); + return -EPROTO; + } + + return 0; +} + +static int ssam_pos_get_source(struct ssam_tablet_sw *sw, u32 *source_id) +{ + struct ssam_sources_list sources = {}; + int status; + + status = ssam_pos_get_sources_list(sw, &sources); + if (status) + return status; + + if (sources.count == 0) { + dev_err(&sw->sdev->dev, "no posture sources found\n"); + return -ENODEV; + } + + /* + * We currently don't know what to do with more than one posture + * source. At the moment, only one source seems to be used/provided. + * The WARN_ON() here should hopefully let us know quickly once there + * is a device that provides multiple sources, at which point we can + * then try to figure out how to handle them. + */ + WARN_ON(sources.count > 1); + + *source_id = get_unaligned_le32(&sources.id[0]); + return 0; +} + +SSAM_DEFINE_SYNC_REQUEST_WR(__ssam_pos_get_posture_for_source, __le32, __le32, { + .target_category = SSAM_SSH_TC_POS, + .target_id = 0x01, + .command_id = 0x02, + .instance_id = 0x00, +}); + +static int ssam_pos_get_posture_for_source(struct ssam_tablet_sw *sw, u32 source_id, u32 *posture) +{ + __le32 source_le = cpu_to_le32(source_id); + __le32 rspval_le = 0; + int status; + + status = ssam_retry(__ssam_pos_get_posture_for_source, sw->sdev->ctrl, + &source_le, &rspval_le); + if (status) + return status; + + *posture = le32_to_cpu(rspval_le); + return 0; +} + +static int ssam_pos_get_posture(struct ssam_tablet_sw *sw, u32 *state) +{ + u32 source_id; + int status; + + status = ssam_pos_get_source(sw, &source_id); + if (status) { + dev_err(&sw->sdev->dev, "failed to get posture source ID: %d\n", status); + return status; + } + + status = ssam_pos_get_posture_for_source(sw, source_id, state); + if (status) { + dev_err(&sw->sdev->dev, "failed to get posture value for source %u: %d\n", + source_id, status); + return status; + } + + return 0; +} + +static u32 ssam_pos_sw_notif(struct ssam_event_notifier *nf, const struct ssam_event *event) +{ + struct ssam_tablet_sw *sw = container_of(nf, struct ssam_tablet_sw, notif); + + if (event->command_id != SSAM_EVENT_POS_CID_POSTURE_CHANGED) + return 0; /* Return "unhandled". */ + + if (event->length != sizeof(__le32) * 3) + dev_warn(&sw->sdev->dev, "unexpected payload size: %u\n", event->length); + + schedule_work(&sw->update_work); + return SSAM_NOTIF_HANDLED; +} + +static const struct ssam_tablet_sw_desc ssam_pos_sw_desc = { + .dev = { + .name = "Microsoft Surface POS Tablet Mode Switch", + .phys = "ssam/01:26:01:00:01/input0", + }, + .ops = { + .notify = ssam_pos_sw_notif, + .get_state = ssam_pos_get_posture, + .state_name = ssam_pos_state_name, + .state_is_tablet_mode = ssam_pos_state_is_tablet_mode, + }, + .event = { + .reg = SSAM_EVENT_REGISTRY_SAM, + .id = { + .target_category = SSAM_SSH_TC_POS, + .instance = 0, + }, + .mask = SSAM_EVENT_MASK_TARGET, + }, +}; + + +/* -- Driver registration. -------------------------------------------------- */ + +static const struct ssam_device_id ssam_tablet_sw_match[] = { + { SSAM_SDEV(KIP, 0x01, 0x00, 0x01), (unsigned long)&ssam_kip_sw_desc }, + { SSAM_SDEV(POS, 0x01, 0x00, 0x01), (unsigned long)&ssam_pos_sw_desc }, + { }, +}; +MODULE_DEVICE_TABLE(ssam, ssam_tablet_sw_match); + +static struct ssam_device_driver ssam_tablet_sw_driver = { + .probe = ssam_tablet_sw_probe, + .remove = ssam_tablet_sw_remove, + .match_table = ssam_tablet_sw_match, + .driver = { + .name = "surface_aggregator_tablet_mode_switch", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .pm = &ssam_tablet_sw_pm_ops, + }, +}; +module_ssam_device_driver(ssam_tablet_sw_driver); + +MODULE_AUTHOR("Maximilian Luz "); +MODULE_DESCRIPTION("Tablet mode switch driver for Surface devices using the Surface Aggregator Module"); +MODULE_LICENSE("GPL");