topic Re: how to use ldb/lvds in android8 of imx8mq ? in i.MX Processors

how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Tue, 21 Aug 2018 09:48:32 GMT

Hi anyone:

Is there any document about how to use lvds in android8 of imx8mq platform ?

Best Regards.

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Tue, 21 Aug 2018 10:38:56 GMT

sorry, I got it, it much convert MIPI to LVDS.

Re: how to use ldb/lvds in android8 of imx8mq ?

jamesbone — Tue, 21 Aug 2018 12:53:23 GMT

Hello Jiang,

Can you please share your findings so others can use it?

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Wed, 22 Aug 2018 03:26:44 GMT

Hi Jamesbone:

Not finish yet, I will update after finish.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

venkatesh_selva — Mon, 12 Nov 2018 09:02:20 GMT

Hello Jiang,

Have you done MIPI-DSI for LVDS?

Thanks

Venkatesh

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Mon, 12 Nov 2018 15:10:03 GMT

HI :

yes, I have finish it.

My solution is to use a TI mipi to lvds chip (sn65dsi85).

I integrated it as panel rm67191 (reference to panel-raydium-rm67191.c ) and use DCSS as the display device.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

venkatesh_selva — Thu, 15 Nov 2018 01:06:04 GMT

Hi Jiang,

Thanks for the reply. In my case I'm using SN65DSI84 as bridge and auo t21hvn01 for panel. Can you share your changes in fsl-imx8mq-com.dts & fsl-imx8mq-com.dtsi files?

Can I ask you what panel you have used? If the panel is not similar, I guess I need to write drm brdge driver for panel-simple.c

In my so far combinations I couldn't see DSI clock.

Venkatesh

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Thu, 15 Nov 2018 12:16:22 GMT

HI :

As attachment.

Hope it can help for you.

BTW, some clock doesn't support by imx8mq, you can higher it up a little.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

念祖姚 — Mon, 17 Dec 2018 03:39:22 GMT

Hi Jiang：

Thanks for your share！ I added the panel-sn65dsix.c and panel-dsi85.h into my ststem， and I encountered such a problem，the dmesg indicated that

the mipi_dsi_bridge can't find the i2c client device sn65dsi8x.

I added some log massages and then i find that the sn65dsi8x client_dev->dev.driver = NULL. Is the sn65dsi8x need a i2c device driver?, Have you encountered this problem?

My kernel log:

   [ 1.052093] [drm] Initialized
   [ 1.061372] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
   [ 1.068015] [drm] No driver support for vblank timestamp query.
   [ 1.074129] imx-drm display-subsystem: bound imx-dcss-crtc.0 (ops dcss_crtc_ops)
   [ 1.081637] nwl_dsi-imx mipi_dsi@30A00000: Using DCSS as input source
   [ 1.088478] panel-ti-sn65dsi8x 30a00000.mipi_dsi_bridge.0: failed to find client platform device
   [ 1.097285] panel-ti-sn65dsi8x 30a00000.mipi_dsi_bridge.0: Yao-log:client_dev->dev.driver == NULL!!!
   [ 1.106541] nwl-mipi-dsi 30a00000.mipi_dsi_bridge: [drm:nwl_dsi_host_attach] lanes=4, format=0x0 flags=0x813
   [ 1.116450] imx-drm display-subsystem: bound mipi_dsi@30A00000 (ops imx_nwl_dsi_component_ops)
   [ 1.129560] [drm] OPIPE_CFG: gamut = 3, nl = 1, pr = 1, pix_format = 875713089
   [ 1.655077] function:sn65_panel_enable line:1044 -----------
   [ 1.721128] Console: switching to colour frame buffer device 240x67
   [ 1.783389] imx-drm display-subsystem: fb0: frame buffer device

Thanks & Best Regards

姚念祖

Mail：982586047@qq.com

Address: 武汉市洪山区光谷大道特一号国际企业中心

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Tue, 18 Dec 2018 02:54:26 GMT

Hi：

It just a simple driver provided i2c client for panel-sn65dsi.c.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

leemeiyung — Mon, 21 Jan 2019 09:44:11 GMT

HI Jiang:

Follow your offered sn65dsi85 driver, I can dispaly 800x600@60Hz while use sn65dsi84 for mipi conver lvds， but encounter an "no singal" tips on another LCD with 1920x1080 resolution， when set CCSR 0x3c as 0x10, I can got the test pattern, could you remind me what's wrong in the process。

BTW，use the same dts and kernel, I do the blowing test:

1) test pattern with single lvds chanel mode on a 800x600 lcd -- ok

2) mipidsi show image to lvds single lvds chanel mode on 800x600 lcd -ok

3) test pattern with dual lvds chanel mode on a 1920x1080 lcd -- ok

4) test pattern witch dual lvds chanel mode (forced in 800x600@60hz) on the 1920x1080 lcd -ok

5) mipi dsi show image to lvds with dual lvds chanel mode (forced in 800x600@60hz) fail, but while connect the 800x600 resolution lcd in one lvds channel, i got the image.

Thanks.

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Tue, 22 Jan 2019 02:03:10 GMT

HI Lee:

Most likely it's the display_timing problem.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

oliverkuo — Tue, 16 Apr 2019 07:50:10 GMT

Hi Frank,

I'm also trying to enable sn65dsi84 on our custom board, we use a 1024*600 LVDS panel.

However, the DSI driver can't work out the CM/CN/CO values for D-PHY ref_clk.

Could you share your dts file and timing table of the panel?

imx_nwl_try_phy_speed (583): bit_clk = 403200000 ; pixclock = 50400000

nwl_dsi-imx mipi_dsi@30A00000: [drm:imx_nwl_try_phy_speed] *ERROR* Cannot setup PHY for mode: 1024x600 @50400 kHz

nwl_dsi-imx mipi_dsi@30A00000: [drm:imx_nwl_try_phy_speed] *ERROR* PHY_REF clk: 27000000, bit clk: 403200000

Thanks a lot.

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Thu, 18 Apr 2019 01:51:14 GMT

HI :

you can turn up the frequency.

For 1024*600 LVDS, I success in kernel 4.9 but fail in 4.14.

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

oliverkuo — Thu, 25 Apr 2019 03:01:59 GMT

Hi,

Thanks for your reply.

I found the algorithm of computing CM/CN/CO was revised in Linux version(4.14.98), I think this issue will be fixed on next release.

Re: how to use ldb/lvds in android8 of imx8mq ?

merlinthewizard — Fri, 06 Sep 2019 14:48:33 GMT

Hi Jiang,

I'm trying to add sn65dsi84 to my kernel but I have some trouble with device tree, it is possible to have your entire dts? I'm not very skilled in this stuff yet and I guess I'm making mny errors.

Let me know,

Thanks

Re: how to use ldb/lvds in android8 of imx8mq ?

jiangyaqiang — Mon, 09 Sep 2019 01:57:22 GMT

HI merilin:

It's the same with fsl-imx8mq-evk-dcss-rm67191.dtsi except:

江亚强

软件工程师

Shenzhen Huameishi Technology Co., Ltd

深圳市华美视科技有限公司

深圳市南山区科苑路6号科技园工业大厦605

Tel：0755-26037882-616

Mail:yaqiang.jiang@huameishi.com

Re: how to use ldb/lvds in android8 of imx8mq ?

lswdneil — Wed, 23 Oct 2019 09:41:44 GMT

Hi, Jiang:

Thank you for your sn65dsi84 's code . I have used it and the LCD(1920X1080) can show . but met some questions, please see the attched file, 1.) the screen shift to right 2.) the colors have distortion.

Can you give me some advice?

thanks.

13534273512

Thomas He.

Re: how to use ldb/lvds in android8 of imx8mq ?

hankwang — Wed, 27 Nov 2019 05:25:59 GMT

Hi Dong,

Do you have resolved this issue? I have the same issue.

Re: how to use ldb/lvds in android8 of imx8mq ?

hankwang — Thu, 28 Nov 2019 06:41:44 GMT

The issue fixed. The dsi parameters must be modified as below :

The dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_CLOCK_NON_CONTINUOUS.