5f651b8704
When the host controller accepts only 32bit writes, the value of the
16bit TRANSFER_MODE register, that has the same 32bit address as the
16bit COMMAND register, needs to be saved and it will be written
in a 32bit write together with the command as this will trigger the
host to send the command on the SD interface.
When sending the tuning command, TRANSFER_MODE is written and then
sdhci_set_transfer_mode reads it back to clear AUTO_CMD12 bit and
write it again resulting in wrong value to be written because the
initial write value was saved in a shadow and the read-back returned
a wrong value, from the register.
Fix sdhci_iproc_readw to return the saved value of TRANSFER_MODE
when a saved value exist.
Same fix for read of BLOCK_SIZE and BLOCK_COUNT registers, that are
saved for a different reason, although a scenario that will cause the
mentioned problem on this registers is not probable.
Fixes: b580c52d58d9 ("mmc: sdhci-iproc: add IPROC SDHCI driver")
Signed-off-by: Corneliu Doban <corneliu.doban@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org # v4.1+
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.