[RFC PATCH] brcmfmac: add 43751 SDIO ids and initialization

[Marc Gonzalez]

On 09/03/2023 18:51, Marc Gonzalez wrote:

> On 09/03/2023 15:29, Ulf Hansson wrote:
> 
>> To narrow down the problem, I would start by preventing the WiFi
>> driver from being insmoded. To make sure it doesn't affect the SDIO
>> card detection process.
>>
>> The point is, the SDIO card should be detected properly, no matter
>> whether there is a corresponding SDIO func driver (WiFi driver)
>> available for it. For a detected SDIO/eMMC/SD card, mmc_add_card()
>> prints a message about the card in the log during initialization. It
>> could look like the below print, for example:
>>
>> "mmc2: new ultra high speed SDR104 SDIO card at address 0001".
> 
> OK, I built the WiFi driver as a module which is NOT loaded at boot time.

Still trying to bisect this heisenbug into submission... :(

So far, I've pared it down to mmc_attach_sdio()

When probe WORKS, mmc_attach_sdio() returns 0.
When probe FAILS, mmc_attach_sdio() returns ETIMEDOUT
via mmc_send_io_op_cond(host, 0, &ocr);

Wrapping mmc_send_io_op_cond() in a loop
makes it work on the second try.

Would appreciate additional guidance. Am mostly stabbing in the dark :)

Regards