Hi Angelo, On Thu, 2023-09-28 at 12:24 +0200, AngeloGioacchino Del Regno wrote: > Il 28/09/23 05:39, Shawn Sung (宋孝謙) ha scritto: > > Hi CK, > > > > On Thu, 2023-09-28 at 03:05 +0000, CK Hu (胡俊光) wrote: > > > Hi, Hsiao-chien: > > > > > > On Mon, 2023-09-11 at 15:42 +0800, Hsiao Chien Sung wrote: > > > > Padding is a new display module on MT8188, it provides ability > > > > to add pixels to width and height of a layer with specified > > > > colors. > > > > > > > > Due to hardware design, Mixer in VDOSYS1 requires width of a > > > > layer > > > > to be 2-pixel-align, or 4-pixel-align when ETHDR is enabled, > > > > we need Padding to deal with odd width. > > > > > > > > Please notice that even if the Padding is in bypass mode, > > > > settings in register must be cleared to 0, > > > > or undefined behaviors could happen. > > > > > > You just set padding to bypass mode and not clear settings to 0. > > > Any > > > thing wrong? > > > > > > > Since the deafult value of all the registers in Padding is zero, > > and > > we are not using Padding currently, it's fine if we just set > > padding to > > bypass mode witout clearing other registers. > > > > The comment is just a reminder in case we forget it in the future. > > Do *not* rely on default register values, because you don't know what > booted > Linux in the first place: you shall *not* expect a clean state and > you shall > *not* expect a clean boot. > > Besides, what I see is that you're setting GENMASK(1, 0) without > explaining > why in the code: you have to add at least the definitions for > PADDING_EN and > PADDING_BYPASS. > > I also don't see why you shouldn't add at least basic handling for > this block, > as it looks easy enough: after all, you anyway have to make sure that > the > registers are cleared - might as well just add a little more effort > on top > and actually set them to meaningful values? That's ultimately your > choice, but > I don't want to see any GENMASK(31,0) write even for register > clearing. > > Please make this driver proper. > Thank you for the suggestions. I'll implement it in the next version. Thanks, Shawn
