blob: 4428c4330229ad3d4bf6e161e9f4070931499451 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Surface System Aggregator Module (SSAM) client device registry.
*
* Registry for non-platform/non-ACPI SSAM client devices, i.e. devices that
* cannot be auto-detected. Provides device-hubs and performs instantiation
* for these devices.
*
* Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
*/
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/limits.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/surface_aggregator/controller.h>
#include <linux/surface_aggregator/device.h>
/* -- Device registry. ------------------------------------------------------ */
/*
* SSAM device names follow the SSAM module alias, meaning they are prefixed
* with 'ssam:', followed by domain, category, target ID, instance ID, and
* function, each encoded as two-digit hexadecimal, separated by ':'. In other
* words, it follows the scheme
*
* ssam:dd:cc:tt:ii:ff
*
* Where, 'dd', 'cc', 'tt', 'ii', and 'ff' are the two-digit hexadecimal
* values mentioned above, respectively.
*/
/* Root node. */
static const struct software_node ssam_node_root = {
.name = "ssam_platform_hub",
};
/* Base device hub (devices attached to Surface Book 3 base). */
static const struct software_node ssam_node_hub_base = {
.name = "ssam:00:00:02:00:00",
.parent = &ssam_node_root,
};
/* AC adapter. */
static const struct software_node ssam_node_bat_ac = {
.name = "ssam:01:02:01:01:01",
.parent = &ssam_node_root,
};
/* Primary battery. */
static const struct software_node ssam_node_bat_main = {
.name = "ssam:01:02:01:01:00",
.parent = &ssam_node_root,
};
/* Secondary battery (Surface Book 3). */
static const struct software_node ssam_node_bat_sb3base = {
.name = "ssam:01:02:02:01:00",
.parent = &ssam_node_hub_base,
};
/* Platform profile / performance-mode device. */
static const struct software_node ssam_node_tmp_pprof = {
.name = "ssam:01:03:01:00:01",
.parent = &ssam_node_root,
};
/* DTX / detachment-system device (Surface Book 3). */
static const struct software_node ssam_node_bas_dtx = {
.name = "ssam:01:11:01:00:00",
.parent = &ssam_node_root,
};
/* HID keyboard. */
static const struct software_node ssam_node_hid_main_keyboard = {
.name = "ssam:01:15:02:01:00",
.parent = &ssam_node_root,
};
/* HID touchpad. */
static const struct software_node ssam_node_hid_main_touchpad = {
.name = "ssam:01:15:02:03:00",
.parent = &ssam_node_root,
};
/* HID device instance 5 (unknown HID device). */
static const struct software_node ssam_node_hid_main_iid5 = {
.name = "ssam:01:15:02:05:00",
.parent = &ssam_node_root,
};
/* HID keyboard (base hub). */
static const struct software_node ssam_node_hid_base_keyboard = {
.name = "ssam:01:15:02:01:00",
.parent = &ssam_node_hub_base,
};
/* HID touchpad (base hub). */
static const struct software_node ssam_node_hid_base_touchpad = {
.name = "ssam:01:15:02:03:00",
.parent = &ssam_node_hub_base,
};
/* HID device instance 5 (unknown HID device, base hub). */
static const struct software_node ssam_node_hid_base_iid5 = {
.name = "ssam:01:15:02:05:00",
.parent = &ssam_node_hub_base,
};
/* HID device instance 6 (unknown HID device, base hub). */
static const struct software_node ssam_node_hid_base_iid6 = {
.name = "ssam:01:15:02:06:00",
.parent = &ssam_node_hub_base,
};
/*
* Devices for 5th- and 6th-generations models:
* - Surface Book 2,
* - Surface Laptop 1 and 2,
* - Surface Pro 5 and 6.
*/
static const struct software_node *ssam_node_group_gen5[] = {
&ssam_node_root,
&ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Book 3. */
static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_root,
&ssam_node_hub_base,
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_bat_sb3base,
&ssam_node_tmp_pprof,
&ssam_node_bas_dtx,
&ssam_node_hid_base_keyboard,
&ssam_node_hid_base_touchpad,
&ssam_node_hid_base_iid5,
&ssam_node_hid_base_iid6,
NULL,
};
/* Devices for Surface Laptop 3 and 4. */
static const struct software_node *ssam_node_group_sl3[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_tmp_pprof,
&ssam_node_hid_main_keyboard,
&ssam_node_hid_main_touchpad,
&ssam_node_hid_main_iid5,
NULL,
};
/* Devices for Surface Laptop Go. */
static const struct software_node *ssam_node_group_slg1[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Pro 7 and Surface Pro 7+. */
static const struct software_node *ssam_node_group_sp7[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_tmp_pprof,
NULL,
};
/* -- Device registry helper functions. ------------------------------------- */
static int ssam_uid_from_string(const char *str, struct ssam_device_uid *uid)
{
u8 d, tc, tid, iid, fn;
int n;
n = sscanf(str, "ssam:%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn);
if (n != 5)
return -EINVAL;
uid->domain = d;
uid->category = tc;
uid->target = tid;
uid->instance = iid;
uid->function = fn;
return 0;
}
static int ssam_hub_remove_devices_fn(struct device *dev, void *data)
{
if (!is_ssam_device(dev))
return 0;
ssam_device_remove(to_ssam_device(dev));
return 0;
}
static void ssam_hub_remove_devices(struct device *parent)
{
device_for_each_child_reverse(parent, NULL, ssam_hub_remove_devices_fn);
}
static int ssam_hub_add_device(struct device *parent, struct ssam_controller *ctrl,
struct fwnode_handle *node)
{
struct ssam_device_uid uid;
struct ssam_device *sdev;
int status;
status = ssam_uid_from_string(fwnode_get_name(node), &uid);
if (status)
return status;
sdev = ssam_device_alloc(ctrl, uid);
if (!sdev)
return -ENOMEM;
sdev->dev.parent = parent;
sdev->dev.fwnode = node;
status = ssam_device_add(sdev);
if (status)
ssam_device_put(sdev);
return status;
}
static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *ctrl,
struct fwnode_handle *node)
{
struct fwnode_handle *child;
int status;
fwnode_for_each_child_node(node, child) {
/*
* Try to add the device specified in the firmware node. If
* this fails with -EINVAL, the node does not specify any SSAM
* device, so ignore it and continue with the next one.
*/
status = ssam_hub_add_device(parent, ctrl, child);
if (status && status != -EINVAL)
goto err;
}
return 0;
err:
ssam_hub_remove_devices(parent);
return status;
}
/* -- SSAM base-hub driver. ------------------------------------------------- */
/*
* Some devices (especially battery) may need a bit of time to be fully usable
* after being (re-)connected. This delay has been determined via
* experimentation.
*/
#define SSAM_BASE_UPDATE_CONNECT_DELAY msecs_to_jiffies(2500)
enum ssam_base_hub_state {
SSAM_BASE_HUB_UNINITIALIZED,
SSAM_BASE_HUB_CONNECTED,
SSAM_BASE_HUB_DISCONNECTED,
};
struct ssam_base_hub {
struct ssam_device *sdev;
enum ssam_base_hub_state state;
struct delayed_work update_work;
struct ssam_event_notifier notif;
};
SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
.target_category = SSAM_SSH_TC_BAS,
.target_id = 0x01,
.command_id = 0x0d,
.instance_id = 0x00,
});
#define SSAM_BAS_OPMODE_TABLET 0x00
#define SSAM_EVENT_BAS_CID_CONNECTION 0x0c
static int ssam_base_hub_query_state(struct ssam_base_hub *hub, enum ssam_base_hub_state *state)
{
u8 opmode;
int status;
status = ssam_retry(ssam_bas_query_opmode, hub->sdev->ctrl, &opmode);
if (status < 0) {
dev_err(&hub->sdev->dev, "failed to query base state: %d\n", status);
return status;
}
if (opmode != SSAM_BAS_OPMODE_TABLET)
*state = SSAM_BASE_HUB_CONNECTED;
else
*state = SSAM_BASE_HUB_DISCONNECTED;
return 0;
}
static ssize_t ssam_base_hub_state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct ssam_base_hub *hub = dev_get_drvdata(dev);
bool connected = hub->state == SSAM_BASE_HUB_CONNECTED;
return sysfs_emit(buf, "%d\n", connected);
}
static struct device_attribute ssam_base_hub_attr_state =
__ATTR(state, 0444, ssam_base_hub_state_show, NULL);
static struct attribute *ssam_base_hub_attrs[] = {
&ssam_base_hub_attr_state.attr,
NULL,
};
static const struct attribute_group ssam_base_hub_group = {
.attrs = ssam_base_hub_attrs,
};
static void ssam_base_hub_update_workfn(struct work_struct *work)
{
struct ssam_base_hub *hub = container_of(work, struct ssam_base_hub, update_work.work);
struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
enum ssam_base_hub_state state;
int status = 0;
status = ssam_base_hub_query_state(hub, &state);
if (status)
return;
if (hub->state == state)
return;
hub->state = state;
if (hub->state == SSAM_BASE_HUB_CONNECTED)
status = ssam_hub_add_devices(&hub->sdev->dev, hub->sdev->ctrl, node);
else
ssam_hub_remove_devices(&hub->sdev->dev);
if (status)
dev_err(&hub->sdev->dev, "failed to update base-hub devices: %d\n", status);
}
static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
{
struct ssam_base_hub *hub = container_of(nf, struct ssam_base_hub, notif);
unsigned long delay;
if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
return 0;
if (event->length < 1) {
dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
return 0;
}
/*
* Delay update when the base is being connected to give devices/EC
* some time to set up.
*/
delay = event->data[0] ? SSAM_BASE_UPDATE_CONNECT_DELAY : 0;
schedule_delayed_work(&hub->update_work, delay);
/*
* Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
* consumed by the detachment system driver. We're just a (more or less)
* silent observer.
*/
return 0;
}
static int __maybe_unused ssam_base_hub_resume(struct device *dev)
{
struct ssam_base_hub *hub = dev_get_drvdata(dev);
schedule_delayed_work(&hub->update_work, 0);
return 0;
}
static SIMPLE_DEV_PM_OPS(ssam_base_hub_pm_ops, NULL, ssam_base_hub_resume);
static int ssam_base_hub_probe(struct ssam_device *sdev)
{
struct ssam_base_hub *hub;
int status;
hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
if (!hub)
return -ENOMEM;
hub->sdev = sdev;
hub->state = SSAM_BASE_HUB_UNINITIALIZED;
hub->notif.base.priority = INT_MAX; /* This notifier should run first. */
hub->notif.base.fn = ssam_base_hub_notif;
hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
hub->notif.event.id.target_category = SSAM_SSH_TC_BAS,
hub->notif.event.id.instance = 0,
hub->notif.event.mask = SSAM_EVENT_MASK_NONE;
hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
INIT_DELAYED_WORK(&hub->update_work, ssam_base_hub_update_workfn);
ssam_device_set_drvdata(sdev, hub);
status = ssam_notifier_register(sdev->ctrl, &hub->notif);
if (status)
return status;
status = sysfs_create_group(&sdev->dev.kobj, &ssam_base_hub_group);
if (status)
goto err;
schedule_delayed_work(&hub->update_work, 0);
return 0;
err:
ssam_notifier_unregister(sdev->ctrl, &hub->notif);
cancel_delayed_work_sync(&hub->update_work);
ssam_hub_remove_devices(&sdev->dev);
return status;
}
static void ssam_base_hub_remove(struct ssam_device *sdev)
{
struct ssam_base_hub *hub = ssam_device_get_drvdata(sdev);
sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group);
ssam_notifier_unregister(sdev->ctrl, &hub->notif);
cancel_delayed_work_sync(&hub->update_work);
ssam_hub_remove_devices(&sdev->dev);
}
static const struct ssam_device_id ssam_base_hub_match[] = {
{ SSAM_VDEV(HUB, 0x02, SSAM_ANY_IID, 0x00) },
{ },
};
static struct ssam_device_driver ssam_base_hub_driver = {
.probe = ssam_base_hub_probe,
.remove = ssam_base_hub_remove,
.match_table = ssam_base_hub_match,
.driver = {
.name = "surface_aggregator_base_hub",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.pm = &ssam_base_hub_pm_ops,
},
};
/* -- SSAM platform/meta-hub driver. ---------------------------------------- */
static const struct acpi_device_id ssam_platform_hub_match[] = {
/* Surface Pro 4, 5, and 6 (OMBR < 0x10) */
{ "MSHW0081", (unsigned long)ssam_node_group_gen5 },
/* Surface Pro 6 (OMBR >= 0x10) */
{ "MSHW0111", (unsigned long)ssam_node_group_gen5 },
/* Surface Pro 7 */
{ "MSHW0116", (unsigned long)ssam_node_group_sp7 },
/* Surface Pro 7+ */
{ "MSHW0119", (unsigned long)ssam_node_group_sp7 },
/* Surface Book 2 */
{ "MSHW0107", (unsigned long)ssam_node_group_gen5 },
/* Surface Book 3 */
{ "MSHW0117", (unsigned long)ssam_node_group_sb3 },
/* Surface Laptop 1 */
{ "MSHW0086", (unsigned long)ssam_node_group_gen5 },
/* Surface Laptop 2 */
{ "MSHW0112", (unsigned long)ssam_node_group_gen5 },
/* Surface Laptop 3 (13", Intel) */
{ "MSHW0114", (unsigned long)ssam_node_group_sl3 },
/* Surface Laptop 3 (15", AMD) and 4 (15", AMD) */
{ "MSHW0110", (unsigned long)ssam_node_group_sl3 },
/* Surface Laptop 4 (13", Intel) */
{ "MSHW0250", (unsigned long)ssam_node_group_sl3 },
/* Surface Laptop Go 1 */
{ "MSHW0118", (unsigned long)ssam_node_group_slg1 },
{ },
};
MODULE_DEVICE_TABLE(acpi, ssam_platform_hub_match);
static int ssam_platform_hub_probe(struct platform_device *pdev)
{
const struct software_node **nodes;
struct ssam_controller *ctrl;
struct fwnode_handle *root;
int status;
nodes = (const struct software_node **)acpi_device_get_match_data(&pdev->dev);
if (!nodes)
return -ENODEV;
/*
* As we're adding the SSAM client devices as children under this device
* and not the SSAM controller, we need to add a device link to the
* controller to ensure that we remove all of our devices before the
* controller is removed. This also guarantees proper ordering for
* suspend/resume of the devices on this hub.
*/
ctrl = ssam_client_bind(&pdev->dev);
if (IS_ERR(ctrl))
return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl);
status = software_node_register_node_group(nodes);
if (status)
return status;
root = software_node_fwnode(&ssam_node_root);
if (!root) {
software_node_unregister_node_group(nodes);
return -ENOENT;
}
set_secondary_fwnode(&pdev->dev, root);
status = ssam_hub_add_devices(&pdev->dev, ctrl, root);
if (status) {
set_secondary_fwnode(&pdev->dev, NULL);
software_node_unregister_node_group(nodes);
}
platform_set_drvdata(pdev, nodes);
return status;
}
static int ssam_platform_hub_remove(struct platform_device *pdev)
{
const struct software_node **nodes = platform_get_drvdata(pdev);
ssam_hub_remove_devices(&pdev->dev);
set_secondary_fwnode(&pdev->dev, NULL);
software_node_unregister_node_group(nodes);
return 0;
}
static struct platform_driver ssam_platform_hub_driver = {
.probe = ssam_platform_hub_probe,
.remove = ssam_platform_hub_remove,
.driver = {
.name = "surface_aggregator_platform_hub",
.acpi_match_table = ssam_platform_hub_match,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
/* -- Module initialization. ------------------------------------------------ */
static int __init ssam_device_hub_init(void)
{
int status;
status = platform_driver_register(&ssam_platform_hub_driver);
if (status)
return status;
status = ssam_device_driver_register(&ssam_base_hub_driver);
if (status)
platform_driver_unregister(&ssam_platform_hub_driver);
return status;
}
module_init(ssam_device_hub_init);
static void __exit ssam_device_hub_exit(void)
{
ssam_device_driver_unregister(&ssam_base_hub_driver);
platform_driver_unregister(&ssam_platform_hub_driver);
}
module_exit(ssam_device_hub_exit);
MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module");
MODULE_LICENSE("GPL");