This one patch does too much to be reviewed easily. One patch is supposed to modify/add one thing at a time in the kernel. Separating platform specific code from imx-drm/imx-hdmi is one thing. Adding support for multi-byte register access is something different. i.e. Something like. 1/3 split platform specific code out. 2/3 move/rename imx-hdmi outside the folder 3/3 add support for multi byte register width access. If there are other things that are not directly relevant to the patch, it goes in a different patch. Bug fixes are also separate. This should result in readable patches that can be reviewed easily. Also, the approach with 4 byte access is ok. But you could use reg-shifts as well perhaps. Then you won't have to change so much of the code. static inline void hdmi_writeb(struct dwc_hdmi *hdmi, u8 val, int offset) +{ + writeb(val, hdmi->regs + (offset << hdmi->reg_shift)); +} + +static inline u8 hdmi_readb(struct dwc_hdmi *hdmi, int offset) +{ + return readb(hdmi->regs + (offset << hdmi->reg_shift)); +} And then in probe +hdmi->reg_shift = 0; + + if (of_property_read_u32(np, "reg-shift", &hdmi->reg_shift)) + dev_warn(hdmi->dev, "No reg-shift\n"); This way the reg-shift property can be defined using DT Cheers, ZubairLK On 05/11/14 12:59, Andy Yan wrote: > imx6 and rockchip rk3288 and JZ4780 (Ingenic Xburst/MIPS) > use the interface compatible Designware HDMI IP, but they > also have some lightly difference, such as phy pll configuration, > register width(imx hdmi register is one byte, but rk3288 is 4 > bytes width), 4K support(imx6 doesn't support 4k, but rk3288 does), > clk useage,and the crtc mux configuration is also platform specific. > > To reuse the imx hdmi driver, split the platform specific code out > to dw_hdmi-imx.c. > > Signed-off-by: Andy Yan <andy.yan@xxxxxxxxxxxxxx> > --- > drivers/staging/imx-drm/Makefile | 2 +- > drivers/staging/imx-drm/dw_hdmi-imx.c | 214 ++++++++++ > drivers/staging/imx-drm/imx-hdmi.c | 726 ++++++++++++++-------------------- > include/drm/bridge/dw_hdmi.h | 114 ++++++ > 4 files changed, 634 insertions(+), 422 deletions(-) > create mode 100644 drivers/staging/imx-drm/dw_hdmi-imx.c > create mode 100644 include/drm/bridge/dw_hdmi.h -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html