Input: pm8941-pwrkey - simulate missed key press events

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@codeaurora.org>
Signed-off-by: Anjelique Melendez <quic_amelende@quicinc.com>
Link: https://lore.kernel.org/r/20220422191239.6271-6-quic_amelende@quicinc.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/misc/pm8941-pwrkey.c b/drivers/input/misc/pm8941-pwrkey.c
index 4ae6d0f6afa3e6a61a882dc7dd87ef68d10873c8..549df01b6ee33eb29b3ecf9fd22c351948745ce0 100644 (file)
--- a/drivers/input/misc/pm8941-pwrkey.c
+++ b/drivers/input/misc/pm8941-pwrkey.c
@@ -77,6 +77,7 @@ struct pm8941_pwrkey {
        u32 code;
        u32 sw_debounce_time_us;
        ktime_t sw_debounce_end_time;
+       bool last_status;
        const struct pm8941_data *data;
 };
 
@@ -167,6 +168,16 @@ 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);