[PATCH 2/3 V4] Bluetooth: hci_h5: btrtl: Add support for RTL8821CS

[Chris Morgan]

On Mon, Mar 13, 2023 at 11:36:21AM -0700, Vasily Khoruzhick wrote:
> On Mon, Mar 13, 2023 at 11:12 AM Chris Morgan <macroalpha82 at gmail.com> wrote:
> >
> > I found the fix, simply put changing the compatible from
> > realtek,rtl8822cs-bt to realtek,rtl8732bs-bt fixes it (because it sets
> > the "H5_INFO_WAKEUP_DISABLE" flag). Is it too late for a V5, or should
> > I submit this as a fix to the devicetree and devicetree documentation?
> 
> But is it actually compatible with rtl8723bs-bt though? I think you
> may need to add an entry for 8821cs to rtl_bluetooth_of_match in
> hci_h5.c

The compatible string would be an exact copy of what is present for
rtl8723bs-bt. Previously I was advised by the devicetree team to just
use a fallback string rather than add a duplicate entry to the driver,
so that's what I did. The driver itself can detect the difference
between the 8821cs and 8723bs and load the appropriate firmware.

Technically the rtl8822cs-bt also works as long as you only want to
"test" the driver and not use it. It's the power management stuff
that causes it to fail roughly 9 out of every 10 times you try to
use it for more than simple pairing (I tested 3 different controllers
with the new compatible string for a total of 7 tests and it works
consistently now).

If you're okay with the compatible string change, I'll update it and
resubmit this as a V5. It shouldn't require a change to the driver,
only the binding.

Thank you.

> 
> > Thank you.
> >
> > On Fri, Mar 10, 2023 at 10:25 AM Chris Morgan <macroalpha82 at gmail.com> wrote:
> > >
> > > I shudder to bring this up now, but I'm encountering a new bug and
> > > might have to withdraw this.
> > >
> > > I'm receiving errors in dmesg of the following, and I can't seem to
> > > figure out the root cause:
> > > Bluetooth: hci0: Out-of-order packet arrived
> > >
> > > Any thoughts on what might cause it?
> > > Thank you.
> > >
> > > On Tue, Feb 28, 2023 at 9:22 AM Chris Morgan <macroalpha82 at gmail.com> wrote:
> > > >
> > > > From: Chris Morgan <macromorgan at hotmail.com>
> > > >
> > > > RTL8821CS is a WiFi + Bluetooth combo chip from Realtek that provides
> > > > WiFi A/B/G/N/AC over an SDIO interface and Bluetooth 4.2 over a UART
> > > > interface.
> > > >
> > > > Note that the firmware this was tested with was firmware version
> > > > 0x75b8f098.
> > > >
> > > > Signed-off-by: Chris Morgan <macromorgan at hotmail.com>
> > > > ---
> > > >  drivers/bluetooth/btrtl.c | 8 ++++++++
> > > >  1 file changed, 8 insertions(+)
> > > >
> > > > diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c
> > > > index 69c3fe649ca7..72947d319fa6 100644
> > > > --- a/drivers/bluetooth/btrtl.c
> > > > +++ b/drivers/bluetooth/btrtl.c
> > > > @@ -128,6 +128,14 @@ static const struct id_table ic_id_table[] = {
> > > >           .fw_name  = "rtl_bt/rtl8821c_fw.bin",
> > > >           .cfg_name = "rtl_bt/rtl8821c_config" },
> > > >
> > > > +       /* 8821CS */
> > > > +       { IC_INFO(RTL_ROM_LMP_8821A, 0xc, 0x8, HCI_UART),
> > > > +         .config_needed = true,
> > > > +         .has_rom_version = true,
> > > > +         .has_msft_ext = true,
> > > > +         .fw_name  = "rtl_bt/rtl8821cs_fw.bin",
> > > > +         .cfg_name = "rtl_bt/rtl8821cs_config" },
> > > > +
> > > >         /* 8761A */
> > > >         { IC_INFO(RTL_ROM_LMP_8761A, 0xa, 0x6, HCI_USB),
> > > >           .config_needed = false,
> > > > --
> > > > 2.34.1
> > > >