[PATCH v4 4/4] input: misc: pm8941-pwrkey: simulate missed key press events

From: Anjelique Melendez
Date: Fri Feb 04 2022 - 17:57:38 EST


From: David Collins <collinsd@xxxxxxxxxxxxxx>

The status of the keys connected to the KPDPWR_N and RESIN_N pins
is identified by reading corresponding bits in the interrupt real
time status register. If the status has changed by the time that
the interrupt is handled then a press event will be missed.

Maintain a last known status variable to find unbalanced release
events and simulate press events for each accordingly.

Signed-off-by: David Collins <collinsd@xxxxxxxxxxxxxx>
Signed-off-by: Anjelique Melendez <quic_amelende@xxxxxxxxxxx>
---
drivers/input/misc/pm8941-pwrkey.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/input/misc/pm8941-pwrkey.c b/drivers/input/misc/pm8941-pwrkey.c
index 881943ab4d55..3519152759dd 100644
--- a/drivers/input/misc/pm8941-pwrkey.c
+++ b/drivers/input/misc/pm8941-pwrkey.c
@@ -76,6 +76,7 @@ struct pm8941_pwrkey {
u32 code;
u32 sw_debounce_time_us;
ktime_t sw_debounce_end_time;
+ bool last_status;
const struct pm8941_data *data;
};

@@ -162,6 +163,16 @@ static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
pwrkey->sw_debounce_end_time = ktime_add_us(ktime_get(),
pwrkey->sw_debounce_time_us);

+ /*
+ * Simulate a press event in case a release event occurred without a
+ * corresponding press event.
+ */
+ if (!pwrkey->last_status && !sts) {
+ input_report_key(pwrkey->input, pwrkey->code, 1);
+ input_sync(pwrkey->input);
+ }
+ pwrkey->last_status = sts;
+
input_report_key(pwrkey->input, pwrkey->code, sts);
input_sync(pwrkey->input);

--
2.34.1