This forces reading the base folded state anytime the device is
probed, to make sure it's in sync.
This is useful after a reboot, if the device re-enumerates for
any reason (e.g. ESD shock), or if the driver is unbound/rebound
(debugging/testing).
Without this, the tablet switch state is only synchronized after a
key is pressed (since the device would then send a report that
includes the switch state), leading to strange UX (e.g. UI
mode changes when a key is pressed after reboot).
This is not a problem on detachable base attach, as the device,
by itself, sends a report after it is booted up.
Signed-off-by: Nicolas Boichat <[email protected]>
---
Instead of all this manual parsing, it'd be easier to just call:
hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
However, that fails silently as hdev->driver_input_lock is held
during probe (or even some callbacks like input_configured.
Changes in v2:
- Improve commit message description.
drivers/hid/hid-google-hammer.c | 85 +++++++++++++++++++++++++--------
1 file changed, 66 insertions(+), 19 deletions(-)
diff --git a/drivers/hid/hid-google-hammer.c b/drivers/hid/hid-google-hammer.c
index 85a054f1ce38..d9319622da44 100644
--- a/drivers/hid/hid-google-hammer.c
+++ b/drivers/hid/hid-google-hammer.c
@@ -392,30 +392,34 @@ static int hammer_input_mapping(struct hid_device *hdev, struct hid_input *hi,
return 0;
}
-static int hammer_event(struct hid_device *hid, struct hid_field *field,
- struct hid_usage *usage, __s32 value)
+static void hammer_folded_event(struct hid_device *hdev, bool folded)
{
unsigned long flags;
- if (usage->hid == HID_USAGE_KBD_FOLDED) {
- spin_lock_irqsave(&cbas_ec_lock, flags);
+ spin_lock_irqsave(&cbas_ec_lock, flags);
- /*
- * If we are getting events from Whiskers that means that it
- * is attached to the lid.
- */
- cbas_ec.base_present = true;
- cbas_ec.base_folded = value;
- hid_dbg(hid, "%s: base: %d, folded: %d\n", __func__,
- cbas_ec.base_present, cbas_ec.base_folded);
-
- if (cbas_ec.input) {
- input_report_switch(cbas_ec.input,
- SW_TABLET_MODE, value);
- input_sync(cbas_ec.input);
- }
+ /*
+ * If we are getting events from Whiskers that means that it
+ * is attached to the lid.
+ */
+ cbas_ec.base_present = true;
+ cbas_ec.base_folded = folded;
+ hid_dbg(hdev, "%s: base: %d, folded: %d\n", __func__,
+ cbas_ec.base_present, cbas_ec.base_folded);
- spin_unlock_irqrestore(&cbas_ec_lock, flags);
+ if (cbas_ec.input) {
+ input_report_switch(cbas_ec.input, SW_TABLET_MODE, folded);
+ input_sync(cbas_ec.input);
+ }
+
+ spin_unlock_irqrestore(&cbas_ec_lock, flags);
+}
+
+static int hammer_event(struct hid_device *hid, struct hid_field *field,
+ struct hid_usage *usage, __s32 value)
+{
+ if (usage->hid == HID_USAGE_KBD_FOLDED) {
+ hammer_folded_event(hid, value);
return 1; /* We handled this event */
}
@@ -457,6 +461,47 @@ static bool hammer_has_backlight_control(struct hid_device *hdev)
HID_GD_KEYBOARD, HID_AD_BRIGHTNESS);
}
+static void hammer_get_folded_state(struct hid_device *hdev)
+{
+ struct hid_report *report;
+ char *buf;
+ int len, rlen;
+ int a;
+
+ report = hdev->report_enum[HID_INPUT_REPORT].report_id_hash[0x0];
+
+ if (!report || report->maxfield < 1)
+ return;
+
+ len = hid_report_len(report) + 1;
+
+ buf = kmalloc(len, GFP_KERNEL);
+ if (!buf)
+ return;
+
+ rlen = hid_hw_raw_request(hdev, report->id, buf, len, report->type, HID_REQ_GET_REPORT);
+
+ if (rlen != len) {
+ hid_warn(hdev, "Unable to read base folded state: %d (expected %d)\n", rlen, len);
+ goto out;
+ }
+
+ for (a = 0; a < report->maxfield; a++) {
+ struct hid_field *field = report->field[a];
+
+ if (field->usage->hid == HID_USAGE_KBD_FOLDED) {
+ u32 value = hid_field_extract(hdev, buf+1,
+ field->report_offset, field->report_size);
+
+ hammer_folded_event(hdev, value);
+ break;
+ }
+ }
+
+out:
+ kfree(buf);
+}
+
static int hammer_probe(struct hid_device *hdev,
const struct hid_device_id *id)
{
@@ -481,6 +526,8 @@ static int hammer_probe(struct hid_device *hdev,
error = hid_hw_open(hdev);
if (error)
return error;
+
+ hammer_get_folded_state(hdev);
}
if (hammer_has_backlight_control(hdev)) {
--
2.30.0.284.gd98b1dd5eaa7-goog
On Fri, 15 Jan 2021, Nicolas Boichat wrote:
> This forces reading the base folded state anytime the device is
> probed, to make sure it's in sync.
>
> This is useful after a reboot, if the device re-enumerates for
> any reason (e.g. ESD shock), or if the driver is unbound/rebound
> (debugging/testing).
>
> Without this, the tablet switch state is only synchronized after a
> key is pressed (since the device would then send a report that
> includes the switch state), leading to strange UX (e.g. UI
> mode changes when a key is pressed after reboot).
>
> This is not a problem on detachable base attach, as the device,
> by itself, sends a report after it is booted up.
>
> Signed-off-by: Nicolas Boichat <[email protected]>
Applied, thanks Nicolas.
--
Jiri Kosina
SUSE Labs