Kernel 6.11 rcN on Dell XPS 15Z:  touch pad has stopped working after the patch commit 8bccf667f62a2351fd0b2a2fe5ba90806702c048 Author: Dmitry Torokhov Date:   Fri Jun 28 15:47:25 2024 -0700     Input: cypress_ps2 - report timeouts when reading command status It seems that the first communication is with an invalid packet of 3 NULLs, and that status failure used to be ignored. With the above patch it is now returning an error and that results in a dead touch pad. The fix is to stop flagging an error for 3-byte null packets, just keep ignoring them as before. [    2.338016] [    T591] err: Command 0x00 response data (0x): 00 00 00 [    2.338032] [    T591] ok: Command 0x00 response data (0x): 33 cc a2 ... [    2.770029] [    T591] ok: Command 0x00 response data (0x): 33 cc a2 [    2.998030] [    T591] ok: Command 0x11 response data (0x): 01 00 64 Signed-off-by: Woody Suwalski --- diff --git a/drivers/input/mouse/cypress_ps2.c b/drivers/input/mouse/cypress_ps2.c index b3c34ebcc4ef..d09272f2fed2 100644 --- a/drivers/input/mouse/cypress_ps2.c +++ b/drivers/input/mouse/cypress_ps2.c @@ -115,8 +115,10 @@ static int cypress_ps2_read_cmd_status(struct psmouse *psmouse,      if (!wait_event_timeout(ps2dev->wait,                  psmouse->pktcnt >= pktsize,                  msecs_to_jiffies(CYTP_CMD_TIMEOUT))) { -        rc = -ETIMEDOUT; -        goto out; +        if (!(pktsize == 3 && param[0] == 0 && param[1] == 0 )) { +            rc = -ETIMEDOUT; +            goto out; +        }      }      memcpy(param, psmouse->packet, pktsize);