i.MX ProcessorsのトピックRe: How to update epdc display using frame buffer in Linux?

How to update epdc display using frame buffer in Linux?

Namitha_zcs — Thu, 06 Feb 2025 06:09:01 GMT

I am using IMX8ULP EVK with epdc display daughter card(IMXEBOOKDC5).After booting using Linux image the epdc display fails to get updated using frame buffer.When checking the power enable pin for display pmic it remains low,even if I write to frame buffer(compared using android image and this pin gets high whenever I update frame buffer fb0).
Furthermore ,I compared between frame buffer driver C files in both android and linux source (drivers/video/fbdev/mxc/mxc_epdc_v2_fb.c).I found that there is a function in android (mxc_epdc_update_data)defined for updating data from user space.

Re: How to update epdc display using frame buffer in Linux?

Zhiming_Liu — Thu, 06 Feb 2025 08:07:13 GMT

Hello @Namitha_zcs

The fb update function in linux driver is mxc_epdc_fb_send_update and defined in mxc_epdc_fb_ioctl, if you use MXCFB_SEND_UPDATE in user space, the update function will be called.

Best Regards,
Zhiming

Re: How to update epdc display using frame buffer in Linux?

Namitha_zcs — Mon, 24 Feb 2025 05:31:36 GMT

Hi Zhiming,
Thankyou for your support.