Hi Linus,
I checked the state of this patch on Devicetree Bindings Patchwork and
it's marked "Changes Requested". I'd be happy to revise the patch but
it's not clear to me what changes are requested. Could you please help
guide me how to proceed?
Sorry if I'm missing something obvious here.
Thanks,
Håkan
On 5/5/2022 6:16 PM, Hakan Jansson wrote:
On 5/5/2022 4:13 PM, Linus Walleij wrote:
I suppose a general flag could be useful but to be honest I don't know
if any other devices besides the ones using the Broadcom driver has any
use for it. You would probably also still want to be able to use
current-speed to set the link speed and end up using both
current-speed=x and current-speed-auto at the same time, which might
look a little confusing?
I do not think it is more confusing than being able to use
current-speed and brcm,uses-autobaud-mode at the same time.
Please let me know if you'd still prefer "current-speed-auto" over
"brcm,uses-autobaud-mode" and I'll revise the patch and rename it!
It actually depends a bit.
This:
+ The controller should be started in autobaud mode by asserting
+ BT_UART_CTS_N (i.e. host RTS) during startup. Only HCI
commands supported
+ in autobaud mode should be used until patch FW has been
loaded.
sounds a bit vague?
Yes, perhaps. I was thinking the details could be helpful but I can
see how they might be perceived as vague and confusing. Maybe it would
be better to just leave it at "The controller should be started in
autobaud mode"?
Does it mean that CTS is asserted, then you send a bit (CTS then goes
low)
and then CTS is asserted again when the device is ready to receieve more
data? i.e is this some kind of one-bit mode, because it doesn't sound
like
it is using CTS as it was used in legacy modems.
CTS and RTS are actually used in the normal way during communication.
The host will assert its RTS to indicate being ready to receive data
from the controller. This flag just controls whether this happens
before or after the controller is powered on. The controller will
check the initial state of its BT_UART_CTS_N pin (connected to host's
RTS) when starting up. It will enter autobaud mode if the signal is
already asserted.
Some more explanation of this mode is needed so we can understand if
this is something generic or a BRCM-only thing.
Yours,
Linus Walleij
Thanks,
Håkan
