551345e77a
[ Upstream commit 88a20edf76091ee7f1bb459b89d714d53f0f8940 ] The microSD card slot in the Sapphire board is not working because of several issues: 1.- The vmmc power supply is missing in the DTS. It is capable of 3.0V and has a GPIO-based enable control. 2.- The vqmmc power supply can provide up to 3.3V, but it is capped in the DTS to just 3.0V because of the vmmc capability. This results in a conflict from the mmc driver requesting an unsupportable voltage range from 3.3V to 3.0V (min > max) as reported in dmesg. So, extend the range up to 3.3V. The hw should be able to stand this 0.3V tolerance. See mmc_regulator_set_vqmmc in drivers/mmc/core/core.c. 3.- The card detect signal is non-working. There is a known conflict with jtag, but the workaround in drivers/soc/rockchip/grf.c does not work. Adding the broken-cd attribute to the DTS fixes the issue. Signed-off-by: Vicente Bergas <vicencb@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Sasha Levin <sashal@kernel.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.