On Thu, Aug 20, 2020 at 3:40 AM Mark Brown <broonie@xxxxxxxxxx> wrote: > > On Wed, Aug 19, 2020 at 11:42:27PM +0800, Tzung-Bi Shih wrote: > > > But I found struct mfd_cell also contains member .of_compatible. What > > is the difference if we use compatible string (as is) for this device > > instead of falling back to use device name to match? > > That's for binding the MFD subdevice to an OF node, you don't need to do > that for a device like this - you can just use the of_node of the parent > to get at the properties. There is an issue we overlooked. In sound/soc/codecs/mt6359.c, mt6359_parse_dt() cannot read the DT properties (https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/tree/sound/soc/codecs/mt6359.c?h=for-next#n2640). The original DTS is as following: pmic { compatible = "mediatek,mt6359"; mt6359codec: mt6359codec { compatible = "mediatek,mt6359-sound"; (1) mediatek,dmic-mode = <1>; mediatek,mic-type-0 = <2>; } } After removing the line at (1), mt6359_parse_dt() cannot read the DT properties. The PMIC drivers/mfd/mt6397-core.c: - "mediatek,mt6359" - has the struct mfd_cell of mt6359-sound - adds all mfd_cells via devm_mfd_add_devices(). The audio codec sound/soc/codecs/mt6359.c: - "mediatek,mt6359-sound" Here are a few options we can come out with. 1. adds back the compatible string in the DTS 2. gets of_node of parent in mt6359.c, and iterates all children nodes to get the desired properties 3. parses all children nodes in the PMIC driver, and put them into either platform_data or device properties (https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/tree/include/linux/mfd/core.h?h=for-next#n77) - The PMIC is common for several sub-devices. It makes less sense to handle subdevice specific logic in the common code. 4. others Could you share with us what would you suggest for fixing the issue?
