Hi, Benjamin > From: Benjamin Tissoires [mailto:benjamin.tissoires@xxxxxxxxxx] > Subject: [WIP PATCH 3/4] ACPI: button: Let input filter out the LID events > > The input stack already filters out the LID events. So instead of > filtering them out at the source, we can hook up after the input > processing and propagate the lid switch events when the input stack > tells us to. > > An other benefit is that if userspace (think libinput) "fixes" the lid > switch state by some heuristics, this new state is forwarded to the > listeners in the kernel. See my comments to PATCH 4. IMO, it sounds better that 1. ACPI lid works as a driver of SW_LID, and 2. i915 registers notification (the only user) via input layer. So it looks i915 rather than button driver should call input_register_handler(). And input layer may help to provide a simplified interface for drivers to register key notifications. Thanks and best regards Lv > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> > --- > drivers/acpi/button.c | 156 ++++++++++++++++++++++++++++++++++++++++++++------ > 1 file changed, 139 insertions(+), 17 deletions(-) > > diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c > index 9ad7604..03e5981 100644 > --- a/drivers/acpi/button.c > +++ b/drivers/acpi/button.c > @@ -109,8 +109,6 @@ struct acpi_button { > struct input_dev *input; > char phys[32]; /* for input device */ > unsigned long pushed; > - int last_state; > - ktime_t last_time; > bool suspended; > }; > > @@ -184,7 +182,6 @@ static int acpi_lid_evaluate_state(struct acpi_device *device) > static int acpi_lid_notify_state(struct acpi_device *device, int state) > { > struct acpi_button *button = acpi_driver_data(device); > - int ret; > > /* button_input_lock must be held */ > > @@ -205,20 +202,129 @@ static int acpi_lid_notify_state(struct acpi_device *device, int state) > if (state) > pm_wakeup_hard_event(&device->dev); > > - ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device); > - if (ret == NOTIFY_DONE) > - ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, > - device); > - if (ret == NOTIFY_DONE || ret == NOTIFY_OK) { > - /* > - * It is also regarded as success if the notifier_chain > - * returns NOTIFY_OK or NOTIFY_DONE. > - */ > - ret = 0; > + return 0; > +} > + > +/* > + * Pass incoming event to all connected clients. > + */ > +static void acpi_button_lid_events(struct input_handle *handle, > + const struct input_value *vals, > + unsigned int count) > +{ > + const struct input_value *v; > + int state = -1; > + int ret; > + > + for (v = vals; v != vals + count; v++) { > + switch (v->type) { > + case EV_SYN: > + if (v->code == SYN_REPORT && state >= 0) { > + ret = blocking_notifier_call_chain(&acpi_lid_notifier, > + state, > + lid_device); > + if (ret == NOTIFY_DONE) > + ret = blocking_notifier_call_chain(&acpi_lid_notifier, > + state, > + lid_device); > + if (ret == NOTIFY_DONE || ret == NOTIFY_OK) { > + /* > + * It is also regarded as success if > + * the notifier_chain returns NOTIFY_OK > + * or NOTIFY_DONE. > + */ > + ret = 0; > + } > + } > + break; > + case EV_SW: > + if (v->code == SW_LID) > + state = !v->value; > + break; > + } > } > - return ret; > } > > +static int acpi_button_lid_connect(struct input_handler *handler, > + struct input_dev *dev, > + const struct input_device_id *id) > +{ > + struct input_handle *handle; > + int error; > + > + handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); > + if (!handle) > + return -ENOMEM; > + > + handle->dev = dev; > + handle->handler = handler; > + handle->name = "acpi-button-lid"; > + > + error = input_register_handle(handle); > + if (error) { > + dev_err(&lid_device->dev, "Error installing input handle\n"); > + goto err_free; > + } > + > + error = input_open_device(handle); > + if (error) { > + dev_err(&lid_device->dev, "Failed to open input device\n"); > + goto err_unregister; > + } > + > + return 0; > + > + err_unregister: > + input_unregister_handle(handle); > + err_free: > + kfree(handle); > + return error; > +} > + > +static void acpi_button_lid_disconnect(struct input_handle *handle) > +{ > + input_close_device(handle); > + input_unregister_handle(handle); > + kfree(handle); > +} > + > +bool acpi_button_lid_match(struct input_handler *handler, > + struct input_dev *dev) > +{ > + struct acpi_button *button; > + > + if (!lid_device) > + return false; > + > + button = acpi_driver_data(lid_device); > + > + if (dev != button->input) > + return false; > + > + return true; > +} > + > +static const struct input_device_id acpi_button_lid_ids[] = { > + { > + .flags = INPUT_DEVICE_ID_MATCH_EVBIT, > + .evbit = { BIT_MASK(EV_SW) }, > + .swbit = { BIT_MASK(SW_LID) }, > + }, > + { }, > +}; > + > +MODULE_DEVICE_TABLE(input, acpi_button_lid_ids); > + > +static struct input_handler acpi_button_lid_handler = { > + .match = acpi_button_lid_match, > + .connect = acpi_button_lid_connect, > + .disconnect = acpi_button_lid_disconnect, > + .events = acpi_button_lid_events, > + .name = "acpi-lid-callchain", > + .id_table = acpi_button_lid_ids, > +}; > + > + > static int acpi_button_state_seq_show(struct seq_file *seq, void *offset) > { > struct acpi_device *device = seq->private; > @@ -581,8 +687,6 @@ static int acpi_button_add(struct acpi_device *device) > strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID); > sprintf(class, "%s/%s", > ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID); > - button->last_state = !!acpi_lid_evaluate_state(device); > - button->last_time = ktime_get(); > } else { > printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid); > error = -ENODEV; > @@ -674,4 +778,22 @@ module_param_call(lid_init_state, > NULL, 0644); > MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state"); > > -module_acpi_driver(acpi_button_driver); > +static int __init acpi_button_init(void) > +{ > + int error; > + > + error = input_register_handler(&acpi_button_lid_handler); > + if (error) > + return error; > + > + return acpi_bus_register_driver(&acpi_button_driver); > +} > + > +static void __exit acpi_button_exit(void) > +{ > + acpi_bus_unregister_driver(&acpi_button_driver); > + input_unregister_handler(&acpi_button_lid_handler); > +} > + > +module_init(acpi_button_init); > +module_exit(acpi_button_exit); > -- > 2.9.4 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
