Re: [PATCH] staging: pi433: set DCC setting to spec recommended value

From: Greg Kroah-Hartman
Date: Tue Nov 22 2022 - 07:09:09 EST


On Sun, Nov 20, 2022 at 01:24:21AM +0530, Deepak R Varma wrote:
> The DCCFreq value is used to obtain the DC offset canceller cut-off
> frequency. Upon device power reset, the bits 7-5 of the RegRxBw register
> that represent the DCCFreq setting are set to 0x4, which evaluates the
> cut-off frequency to be 1% of RxBw.
>
> In the current implementation, first, there is no configuration variable
> defined in the struct pi433_rx_cfg for the user to set this value as
> part of the UAPI. Second, the code simply ignores the value of DCC
> setting and allows it to never change.
>
> As per the RFM69HCW tech specs, the default value for DCC frequency is
> recommended to be 4% of the RxBw; which requires the DCC setting bits
> to be set to 010. So allow the DCC setting to change to recommended /
> default value for improved rx sensitivity.
>
> Signed-off-by: Deepak R Varma <drv@xxxxxxxxx>
> ---
>
> Please Note: The proposed change is compile tested only. I am unable to perform
> device based testing in the absence of the hardware, both the RasPi board and the
> Pi433 device. Please let me know if it is necessary for me to test such patches
> on the real device myself. I will stop sending the patches till I have the hardware
> to test them. Thanks.

For changes like this, you need to test it on the device itself.

thanks,

greg k-h