Re: [PATCH 4/4] Bluetooth: hci_bcm: Increase host baudrate for CYW55572 in autobaud mode

[Hakan Jansson]

Hi Paul,

On 6/20/2022 2:21 PM, Paul Menzel wrote:
> > Add device specific data for max baudrate in autobaud mode. This 
> > allows the
> > host to use a baudrate higher than "init speed" when loading FW in 
> > autobaud
> > mode.
>
> Please mention 921600 in the commit message, and maybe also document
> what the current default is.

Sure, I can do that if I submit a new rev. The default is 115200.

> Please also add the measurement data to the commit message, that means,
> how much is the time to load the firmware decreased.

The actual load time will depend on the specific FW used but I could add 
an example. It would be in the order of seconds.

> > Signed-off-by: Hakan Jansson <hakan.jansson@xxxxxxxxxxxx>
> > ---
> >   drivers/bluetooth/hci_bcm.c | 20 ++++++++++++++++----
> >   1 file changed, 16 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
> > index 0ae627c293c5..d7e0b75db8a6 100644
> > --- a/drivers/bluetooth/hci_bcm.c
> > +++ b/drivers/bluetooth/hci_bcm.c
> > @@ -53,10 +53,12 @@
> >    * struct bcm_device_data - device specific data
> >    * @no_early_set_baudrate: Disallow set baudrate before driver setup()
> >    * @drive_rts_on_open: drive RTS signal on ->open() when platform 
> > requires it
> > + * @max_autobaud_speed: max baudrate supported by device in autobaud 
> > mode
> >    */
> >   struct bcm_device_data {
> >       bool    no_early_set_baudrate;
> >       bool    drive_rts_on_open;
> > +     u32     max_autobaud_speed;
>
> Why specify the length, and not just `unsigned int`? Maybe also add the
> unit to the variable name?

See below.

> >   };
> >
> >   /**
> > @@ -100,6 +102,7 @@ struct bcm_device_data {
> >    * @drive_rts_on_open: drive RTS signal on ->open() when platform 
> > requires it
> >    * @pcm_int_params: keep the initial PCM configuration
> >    * @use_autobaud_mode: start Bluetooth device in autobaud mode
> > + * @max_autobaud_speed: max baudrate supported by device in autobaud 
> > mode
> >    */
> >   struct bcm_device {
> >       /* Must be the first member, hci_serdev.c expects this. */
> > @@ -139,6 +142,7 @@ struct bcm_device {
> >       bool                    drive_rts_on_open;
> >       bool                    use_autobaud_mode;
> >       u8                      pcm_int_params[5];
> > +     u32                     max_autobaud_speed;
>
> Ditto.

I'm trying to following the style of the existing code which already had 
struct members "oper_speed" and "init_speed" declared as u32.


Regards,
Håkan