2021-11-20 08:34:40

by Orlando Chamberlain

[permalink] [raw]
Subject: [PATCH] mfd: intel-lpss-pci: fix clock speed for 38a8 UART

This device is found in the MacBookPro16,2, and as the MacBookPro16,1 is
from the same generation of MacBooks and has a UART with bxt_uart_info,
it was incorrectly assumed that the MacBookPro16,2's UART would have the
same info.

This led to the wrong clock speed being used, and the Bluetooth
controller exposed by the UART receiving and sending random data, which
was incorrectly assumed to be an issue with the Bluetooth stuff, not an
error with the UART side of things.

Changing the info to spt_uart_info changes the clock speed and makes it
send and receive data correctly.

Fixes: ddb1ada416fd ("mfd: intel-lpss: Add support for MacBookPro16,2 ICL-N UART")

Signed-off-by: Orlando Chamberlain <[email protected]>
---
drivers/mfd/intel-lpss-pci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
index a872b4485eac..f70464ce8e3d 100644
--- a/drivers/mfd/intel-lpss-pci.c
+++ b/drivers/mfd/intel-lpss-pci.c
@@ -254,7 +254,7 @@ static const struct pci_device_id intel_lpss_pci_ids[] = {
{ PCI_VDEVICE(INTEL, 0x34eb), (kernel_ulong_t)&bxt_i2c_info },
{ PCI_VDEVICE(INTEL, 0x34fb), (kernel_ulong_t)&spt_info },
/* ICL-N */
- { PCI_VDEVICE(INTEL, 0x38a8), (kernel_ulong_t)&bxt_uart_info },
+ { PCI_VDEVICE(INTEL, 0x38a8), (kernel_ulong_t)&spt_uart_info },
/* TGL-H */
{ PCI_VDEVICE(INTEL, 0x43a7), (kernel_ulong_t)&bxt_uart_info },
{ PCI_VDEVICE(INTEL, 0x43a8), (kernel_ulong_t)&bxt_uart_info },
--
2.34.0




2021-11-22 11:22:47

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH] mfd: intel-lpss-pci: fix clock speed for 38a8 UART

On Sat, Nov 20, 2021 at 08:34:26AM +0000, Orlando Chamberlain wrote:

Thanks, my comments below.

> This device is found in the MacBookPro16,2, and as the MacBookPro16,1 is
> from the same generation of MacBooks and has a UART with bxt_uart_info,
> it was incorrectly assumed that the MacBookPro16,2's UART would have the
> same info.
>
> This led to the wrong clock speed being used, and the Bluetooth
> controller exposed by the UART receiving and sending random data, which
> was incorrectly assumed to be an issue with the Bluetooth stuff, not an
> error with the UART side of things.
>
> Changing the info to spt_uart_info changes the clock speed and makes it
> send and receive data correctly.

> Fixes: ddb1ada416fd ("mfd: intel-lpss: Add support for MacBookPro16,2 ICL-N UART")
>
> Signed-off-by: Orlando Chamberlain <[email protected]>

Tag block shouldn't have blank lines. Otherwise LGTM,
Reviewed-by: Andy Shevchenko <[email protected]>

> drivers/mfd/intel-lpss-pci.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
> index a872b4485eac..f70464ce8e3d 100644
> --- a/drivers/mfd/intel-lpss-pci.c
> +++ b/drivers/mfd/intel-lpss-pci.c
> @@ -254,7 +254,7 @@ static const struct pci_device_id intel_lpss_pci_ids[] = {
> { PCI_VDEVICE(INTEL, 0x34eb), (kernel_ulong_t)&bxt_i2c_info },
> { PCI_VDEVICE(INTEL, 0x34fb), (kernel_ulong_t)&spt_info },
> /* ICL-N */
> - { PCI_VDEVICE(INTEL, 0x38a8), (kernel_ulong_t)&bxt_uart_info },
> + { PCI_VDEVICE(INTEL, 0x38a8), (kernel_ulong_t)&spt_uart_info },
> /* TGL-H */
> { PCI_VDEVICE(INTEL, 0x43a7), (kernel_ulong_t)&bxt_uart_info },
> { PCI_VDEVICE(INTEL, 0x43a8), (kernel_ulong_t)&bxt_uart_info },
> --
> 2.34.0
>
>

--
With Best Regards,
Andy Shevchenko