On Sun, Aug 08, 2021 at 09:44:57PM +0800, Shawn Guo wrote: > On Wed, Aug 04, 2021 at 02:09:19PM +0200, Stephan Gerhold wrote: > > On Wed, Aug 04, 2021 at 04:13:52PM +0800, Shawn Guo wrote: > > > + ... > > > + nt_dcs_write(0xb1, 0x6c, 0x21); > > > + nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00); > > > + nt_dcs_write(0x35, 0x00); > > > + nt_gen_write(0x11, 0x00); > > > + msleep(120); > > > + nt_gen_write(0x29, 0x00); > > > + usleep_range(1000, 1500); > > > + nt_dcs_write(0x53, 0x24); > > > > Did you mix up "nt_dcs_write" and "nt_gen_write" here? > > The nt_gen_write(0x11, 0x00); looks like MIPI_DCS_EXIT_SLEEP_MODE > > and the nt_gen_write(0x29, 0x00); looks like MIPI_DCS_SET_DISPLAY_ON. > > > > For reference you can pull your original reference DTB from Sony through > > my panel driver generator: https://github.com/msm8916-mainline/linux-mdss-dsi-panel-driver-generator > > Wow, very nice! It really deserves wider spread! > > > > > It produces the following (I compiled "msm8939-kanuti_tulip.dtb" > > from https://github.com/sonyxperiadev/kernel/tree/aosp/LA.BR.1.3.3_rb2.14, > > not sure if that is right): > > > > // ... > > dsi_generic_write_seq(dsi, 0x35, 0x00); > > > > ret = mipi_dsi_dcs_exit_sleep_mode(dsi); > > if (ret < 0) { > > dev_err(dev, "Failed to exit sleep mode: %d\n", ret); > > return ret; > > } > > msleep(120); > > > > ret = mipi_dsi_dcs_set_display_on(dsi); > > if (ret < 0) { > > dev_err(dev, "Failed to set display on: %d\n", ret); > > return ret; > > } > > usleep_range(1000, 2000); > > > > dsi_generic_write_seq(dsi, 0x53, 0x24); > > > > Which also suggests that generic and DCS writes are mixed up here. > > > > Note however that you could not use the generated driver as-is, > > because Sony seems to use their own display driver instead of Qualcomm's > > and some things seem to be different. > > I re-created the driver using your generator. With modeling the 5v > control GPIOs with regulators and adding backlight-gpios support, the > driver works quite nicely, except the following two problems: > > 1) I have to drop the MIPI_DSI_MODE_LPM configuration from .update_status > hook. Otherwise brightness did not get updated to panel. > > ---8<------ > diff --git a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c > index 31e5f942a039..eba926c6f722 100644 > --- a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c > +++ b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c > @@ -420,33 +420,23 @@ static int truly_nt35521_bl_update_status(struct backlight_device *bl) > u16 brightness = backlight_get_brightness(bl); > int ret; > > - dsi->mode_flags &= ~MIPI_DSI_MODE_LPM; > - > ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness); > if (ret < 0) > return ret; > > - dsi->mode_flags |= MIPI_DSI_MODE_LPM; > - > return 0; > } > ------>8--- > I have to admit I don't know much about Low Power Mode vs High Speed Mode. As long it works it is good I guess :-) > 2) The driver works good, if the kernel is launched via "fastboot boot". > But if the kernel is flashed to eMMC and launched by bootloader with > splash screen, kernel will fail to bring up the panel. After kernel > boots up, a blank & unblank cycle can get panel work though. > > The problem 2) is not driver generator related. @Konrad, did you see > it on asus-z00t-tm5p5-n35596 driver? > Do you have CONFIG_DRM_MSM=y (built-in) instead of =m (module) maybe? I think a similar issue exists on MSM8916 but it does not happen for some reason if CONFIG_DRM_MSM=m instead of =y. Somehow having it load later during the boot process fixes some things there. Thanks, Stephan
