8c0f4895dc
commit 88a748419b84187fd1da05637b8e5928b04a1e06 upstream. If UHS speed modes are enabled, a compatible SD card switches down to 1.8V during enumeration. If after this a software reboot/crash takes place and on-chip ROM tries to enumerate the SD card, the difference in IO voltages (host @ 3.3V and card @ 1.8V) may end up damaging the card. The fix for this is to have support for power cycling the card in hardware (with a PORz/soft-reset line causing a power cycle of the card). Since am571x-, am572x- and am574x-idk don't have this capability, disable voltage switching for these boards. The major effect of this is that the maximum supported speed mode is now high speed(50 MHz) down from SDR104(200 MHz). Cc: <stable@vger.kernel.org> Signed-off-by: Faiz Abbas <faiz_abbas@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.