This series attempts to deal better with the expected transmission errors related to the idle states (handled by the Always-On-Subsystem or AOS) on the SDIO-based WiFi on rk3288-veyron-minnie, rk3288-veyron-speedy, and rk3288-veyron-mickey. Some details about those errors can be found in <https://crbug.com/960222>, but to summarize it here: if we try to send the wakeup command to the WiFi card at the same time it has decided to wake up itself then it will behave badly on the SDIO bus. This can cause timeouts or CRC errors. When I tested on 4.19 and 4.20 these CRC errors can be seen to cause re-tuning. Since I am currently developing on 4.19 this was the original problem I attempted to solve. On mainline it turns out that you don't see the retuning errors but you see tons of spam about timeouts trying to wakeup from sleep. I tracked down the commit that was causing that and have partially reverted it here. I have no real knowledge about Broadcom WiFi, but the commit that was causing problems sounds (from the descriptioin) to be a hack commit penalizing all Broadcom WiFi users because of a bug in a Cypress SD controller. I will let others comment if this is truly the case and, if so, what the right solution should be. For v3 of this series I have added 2 patches to the end of the series to address errors that would show up on systems with these same SDIO WiFi cards when used on controllers that do periodic retuning. These systems need an extra fix to prevent the retuning from happening when the card is asleep. Changes in v3: - Took out the spinlock since I believe this is all in one context. - Expect errors for all of brcmf_sdio_kso_control() (Adrian). - ("mmc: core: Export mmc_retune_hold_now() mmc_retune_release()") new for v3. - ("brcmfmac: sdio: Don't tune while the card is off") new for v3. Changes in v2: - A full revert, not just a partial one (Arend). ...with explicit Cc. - Updated commit message to clarify based on discussion of v1. Douglas Anderson (5): Revert "brcmfmac: disable command decode in sdio_aos" mmc: core: API for temporarily disabling auto-retuning due to errors brcmfmac: sdio: Disable auto-tuning around commands expected to fail mmc: core: Export mmc_retune_hold_now() mmc_retune_release() brcmfmac: sdio: Don't tune while the card is off drivers/mmc/core/core.c | 19 +++++++++++++++++-- drivers/mmc/core/host.c | 7 +++++++ drivers/mmc/core/host.h | 7 ------- .../broadcom/brcm80211/brcmfmac/sdio.c | 18 +++++++++++++----- include/linux/mmc/core.h | 4 ++++ include/linux/mmc/host.h | 1 + 6 files changed, 42 insertions(+), 14 deletions(-) -- 2.22.0.rc2.383.gf4fbbf30c2-goog
