On Mon, Sep 16, 2013 at 03:52:18PM +0000, KY Srinivasan wrote: > > > > -----Original Message----- > > From: Dmitry Torokhov [mailto:dmitry.torokhov@xxxxxxxxx] > > Sent: Monday, September 16, 2013 8:20 AM > > To: KY Srinivasan > > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > devel@xxxxxxxxxxxxxxxxxxxxxx; linux-input@xxxxxxxxxxxxxxx; vojtech@xxxxxxx; > > olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; jasowang@xxxxxxxxxx > > Subject: Re: [PATCH 1/1] Drivers: input: serio: New driver to support Hyper-V > > synthetic keyboard > > > > Hi K. Y. > > > > On Sun, Sep 15, 2013 at 10:28:54PM -0700, K. Y. Srinivasan wrote: > > > Add a new driver to support synthetic keyboard. On the next generation > > > Hyper-V guest firmware, many legacy devices will not be emulated and this > > > driver will be required. > > > > > > I would like to thank Vojtech Pavlik <vojtech@xxxxxxx> for helping me with the > > > details of the AT keyboard driver. > > > > > > > In addition to what Dan said: > > > > > + > > > +struct synth_kbd_protocol_response { > > > + struct synth_kbd_msg_hdr header; > > > + u32 accepted:1; > > > + u32 reserved:31; > > > +}; > > > > Use of bitfields for on the wire structures makes me uneasy. I know that > > currently you only going to run LE on LE, but still, maybe using > > explicit shifts and masks would be better, > > This definition of the data structure is defined by the host. I will see what I > can do here. You do not really need to change protocol, you just sat that accepted is the bit 0 of the word and define endianness (LE in your case). Then you do: struct synth_kbd_protocol_response { struct synth_kbd_msg_hdr header; __le32 status; } #define KBD_PROTOCOL_ACCEPTED BIT(0) ... status = _le32_to_cpu(response->status); accepted = status & KBD_PROTOCOL_ACCEPTED; Thanks. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
