Hi Dmitry, Am Sonntag, dem 07.03.2021 um 21:47 -0800 schrieb Dmitry Torokhov: > Hi Lucas, > > On Mon, Jan 25, 2021 at 07:25:27PM +0100, Lucas Stach wrote: > > This change allows the device firmware to be updated by putting a firmware > > file in /lib/firmware and providing the name of the file via the update_fw > > sysfs property. The driver will then flash the firmware image into the > > controller internal storage and restart the controller to activate the new > > firmware. > > > > The implementation was done by looking at the the messages passed between > > the controller and proprietary vendor update tool. Not every detail of the > > protocol is totally well understood, so the implementation still has some > > "monkey see, monkey do" parts, as far as they have been found to be required > > for the update to succeed. > > > > Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> > > --- > > .../ABI/testing/sysfs-driver-input-exc3000 | 20 ++ > > drivers/input/touchscreen/exc3000.c | 240 +++++++++++++++++- > > 2 files changed, 258 insertions(+), 2 deletions(-) > > > > diff --git a/Documentation/ABI/testing/sysfs-driver-input-exc3000 b/Documentation/ABI/testing/sysfs-driver-input-exc3000 > > index 704434b277b0..123a00ccee8b 100644 > > --- a/Documentation/ABI/testing/sysfs-driver-input-exc3000 > > +++ b/Documentation/ABI/testing/sysfs-driver-input-exc3000 > > @@ -24,3 +24,23 @@ Description: Reports the type identification provided by the touchscreen, for ex > > Access: Read > > > > > > > > > > Valid values: Represented as string > > + > > +What: /sys/bus/i2c/devices/xxx/update_fw > > +Date: Jan 2021 > > +Contact: linux-input@xxxxxxxxxxxxxxx > > +Description: Allows to specify a firlename of a firmware file located in /lib/firmware/ that will be > > + used to update the application firmware on the touchscreen controller. For example > > + "eeti/eeti_27_0_EDipper_0735.fw" > > I believe the current idiomatic way is to have statically defined > firmware name (it can still encode vid/pid/model info etc) and do not > re-implement variable firmware name in every driver. > > I think if this really is required we need to add this feature of > overriding default firmware name to firmware loader maybe? One issue I see with the driver provided firmware name is that the model name and revision can be changed by the flashed firmware, with the EXC3000 being a i2c device ,we also don't have any stable VID/PID to use as a key. Which is an issue for the initial firmware flashing. In that case one would need to know whats currently on the device to be able to place a firmware file with the correct name. Also I don't really see how that simplifies the driver code, as all this is doing is using the passed in string as a file name to fetch the firmware update file from. To be clear: I'm not totally opposed to using a driver provided firmware name, I just see that it complicates some things that are not an issue with the patch as-is today and would like to understand the reason for pushing for a driver provided name, before deciding one way or the other. Regards, Lucas
