brcmfmac: add comment block in brcmf_sdio_buscore_read()

In brcmf_sdio_buscore_read() there is some special handling upon
register access to chipid register of the chipcommon core. Add
comment explaining why it is done here.

Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
This commit is contained in:
Arend Van Spriel 2018-01-09 13:22:53 +01:00 committed by Kalle Valo
parent c9aa7a91de
commit 32adbcaa5d
1 changed files with 7 additions and 0 deletions

View File

@ -3772,6 +3772,13 @@ static u32 brcmf_sdio_buscore_read32(void *ctx, u32 addr)
val = brcmf_sdiod_readl(sdiodev, addr, NULL);
/*
* this is a bit of special handling if reading the chipcommon chipid
* register. The 4339 is a next-gen of the 4335. It uses the same
* SDIO device id as 4335 and the chipid register returns 4335 as well.
* It can be identified as 4339 by looking at the chip revision. It
* is corrected here so the chip.c module has the right info.
*/
if (addr == CORE_CC_REG(SI_ENUM_BASE, chipid) &&
(sdiodev->func1->device == SDIO_DEVICE_ID_BROADCOM_4339 ||
sdiodev->func1->device == SDIO_DEVICE_ID_BROADCOM_4335_4339)) {