cdb2256f79
The SDIO HW reset procedure in mwifiex_sdio_card_reset_work() is broken, when the SDIO card is shared with another SDIO func driver. This is the case when the Bluetooth btmrvl driver is being used in combination with mwifiex. More precisely, when mwifiex_sdio_card_reset_work() runs to resets the SDIO card, the btmrvl driver doesn't get notified about it. Beyond that point, the btmrvl driver will fail to communicate with the SDIO card. This is a generic problem for SDIO func drivers sharing an SDIO card, which are about to be addressed in subsequent changes to the mmc core and the mmc_hw_reset() interface. In principle, these changes means the mmc_hw_reset() interface starts to return 1 if the are multiple drivers for the SDIO card, as to indicate to the caller that the reset needed to be scheduled asynchronously through a hotplug mechanism of the SDIO card. Let's prepare the mwifiex driver to support the upcoming new behaviour of mmc_hw_reset(), which means extending the mwifiex_sdio_card_reset_work() to support the asynchronous SDIO HW reset path. This also means, we need to allow the ->remove() callback to run, without waiting for the FW to be loaded. Additionally, during system suspend, mwifiex_sdio_suspend() may be called when a reset has been scheduled, but waiting to be executed. In this scenario let's simply return -EBUSY to abort the suspend process, as to allow the reset to be completed first. Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Douglas Anderson <dianders@chromium.org> Cc: stable@vger.kernel.org # v5.4+ Acked-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.