From: Kirill A. Korinsky <kirill@korins.ky>
Subject: Re: sys/ihidev: replace HONOR's touchpad quirk
To: tech@openbsd.org
Date: Sat, 23 May 2026 19:19:46 +0200

On Sat, 23 May 2026 16:23:45 +0200,
Kirill A. Korinsky <kirill@korins.ky> wrote:
> 
> tech@,
> 
> Old quirk made touchpad with multitouch wroks, but it was unstable and
> doesn't work each boot.
> 
> Here better quirck which simple re-reads reports multiple times and
> usually 2-3 repeated read are enough.
> 
> With new quirck multitouch works each boot, I've tested 10 reboot and 10
> cold boot.
> 
> Open questions: shall it be kept as device quirck or generic policy? 
> 
> Ok to commit as a quirk?
> 

I had walk into that with instruments till the HWRITE4() and it seems that
this device always return 0xff on the first GET_REPORT.

Both HWRITE4() write the same command, but the first response is 0xff... and
the second one is meaningful report.

Adding timeout before command do not helps.

I have no better idea that add such quirk.

Which, actually, makes it quite stable.

Thoughs? Suggestions? Ok?

Index: sys/dev/i2c/ihidev.c
===================================================================
RCS file: /home/cvs/src/sys/dev/i2c/ihidev.c,v
diff -u -p -r1.43 ihidev.c
--- sys/dev/i2c/ihidev.c	23 May 2026 11:10:57 -0000	1.43
+++ sys/dev/i2c/ihidev.c	23 May 2026 17:14:57 -0000
@@ -76,7 +76,7 @@ int	ihidev_maxrepid(void *buf, int len);
 int	ihidev_print(void *aux, const char *pnp);
 int	ihidev_submatch(struct device *parent, void *cf, void *aux);
 
-#define IHIDEV_QUIRK_RE_POWER_ON	0x1
+#define IHIDEV_QUIRK_RETRY_GET_REPORT	0x1
 
 const struct ihidev_quirks {
 	uint16_t		ihq_vid;
@@ -84,7 +84,7 @@ const struct ihidev_quirks {
 	int			ihq_quirks;
 } ihidev_devs[] = {
 	/* HONOR MagicBook Art 14 Touchpad (QTEC0002) */
-	{ 0x35cc, 0x0104, IHIDEV_QUIRK_RE_POWER_ON },
+	{ 0x35cc, 0x0104, IHIDEV_QUIRK_RETRY_GET_REPORT },
 };
 
 const struct cfattach ihidev_ca = {
@@ -406,6 +406,17 @@ ihidev_hid_command(struct ihidev_softc *
 		res = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
 		    &cmd, cmdlen, tmprep, report_len, 0);
 
+		if (sc->sc_quirks & IHIDEV_QUIRK_RETRY_GET_REPORT) {
+			/*
+			 * HONOR MagicBook Art 14 Touchpad (QTEC0002) returns
+			 * all 0xff bytes for the first GET_REPORT, but
+			 * meaningful report on the second attemtp.
+			 */
+			memset(tmprep, 0, report_len);
+			res = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
+			    sc->sc_addr, &cmd, cmdlen, tmprep, report_len, 0);
+		}
+
 		d = tmprep[0] | tmprep[1] << 8;
 		if (d != report_len)
 			DPRINTF(("%s: response size %d != expected length %d\n",
@@ -653,23 +664,6 @@ ihidev_hid_desc_parse(struct ihidev_soft
 		printf("%s: failed fetching HID report\n",
 		    sc->sc_dev.dv_xname);
 		return (1);
-	}
-
-	if (sc->sc_quirks & IHIDEV_QUIRK_RE_POWER_ON) {
-		if (ihidev_poweron(sc))
-			return (1);
-
-		/*
-		 * 7.2.8 states that a device shall not respond back
-		 * after receiving the power on command, and must ensure
-		 * that it transitions to power on state in less than 1
-		 * second. The ihidev_poweron function uses a shorter
-		 * sleep, sufficient for the ON-RESET sequence. Here,
-		 * however, it sleeps for the full second to accommodate
-		 * cold boot scenarios on affected devices.
-		 */
-
-		ihidev_sleep(sc, 1000);
 	}
 
 	return (0);


-- 
wbr, Kirill