Add Synaptics firmware member Hi Dmitry, Update Synaptics firmware's comment. [Wayne 08/15] To address the transaction error case in the middle would potential lead to the unexpected data transaction and latency between styk device and host driver. F$03 didn't really parse any data packet but simply works as bridge functionality to bypass the command and response packets between styk device and driver. Thanks Marge Yang -----Original Message----- From: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Sent: Saturday, August 13, 2022 3:28 AM To: margeyang <marge.yang@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> Cc: linux-input@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; hdegoede@xxxxxxxxxx; benjamin.tissoires@xxxxxxxxxx; Marge Yang <Marge.Yang@xxxxxxxxxxxxxxxx>; Derek Cheng <derek.cheng@xxxxxxxxxxxxxxxx>; Vincent Huang <Vincent.huang@xxxxxxxxxxxxxxxx> Subject: Re: [PATCH V2] Input: synaptics-rmi4 - filter incomplete relative packet. CAUTION: Email originated externally, do not click links or open attachments unless you recognize the sender and know the content is safe. Hi Marge, On Fri, Aug 12, 2022 at 04:43:25PM +0800, margeyang wrote: > From: Marge Yang <marge.yang@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> > > RMI4 F03 supports the Stick function, > it's designed to support relative packet. > This patch supports the following case. > When relative packet can't be reported completely, it may miss one > byte or two byte. > New Synaptics firmware will report PARITY error. > When timeout error or parity error happens, > RMI4 driver will sends 0xFE command and ask FW to Re-send stick packet > again. My understanding is that F03 is intended to be a pass-through mechanism for PS/2-compatible devices. In that spirit all protocol handling and validation should happen in psmouse driver that attaches to a serio port provided by F03. Historically we did not pay attention to parity and frame errors for PS/2 mice/touchpads (and for keyboards on x86) but we coudl add such code there. Do we actually observe this with RMI devices? Can RMI firmware handle this better instead? Thanks. -- Dmitry
