Hi, On Tue, Oct 10, 2023 at 4:36 AM cong yang <yangcong5@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hi, > > On Tue, Oct 10, 2023 at 4:44 AM Doug Anderson <dianders@xxxxxxxxxx> wrote: > > > > Hi, > > > > On Fri, Oct 6, 2023 at 11:07 PM Cong Yang > > <yangcong5@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > At present, we have found that there may be a problem of blurred > > > screen during fast sleep/resume. The direct cause of the blurred > > > screen is that the IC does not receive 0x28/0x10. Because of the > > > particularity of the IC, before the panel enters sleep hid must > > > stop scanning, i2c_hid_core_suspend before ili9882t_disable. > > > This doesn't look very spec-compliant. > > > > Presumably you could be more spec compliant if we used > > "panel_follower" in this case? Would that be a better solution? > > In the "panel_follower" solution, the phenomenon is the same. > The current order is > ili9882t_disable=>i2c_hid_core_suspend=>elan_i2c_hid_power_down=>ili9882t_unprepare, > ili9882t need touchpanel stop scanning,i2c_hid_core_suspend before > ili9882t_disable. Ugh, that's unfortunate. Though is there a reason why you couldn't just move the `ili9882t_enter_sleep_mode()` to `ili9882t_unprepare()`? That seems like it should be OK and even perhaps makes it more symmetric with thue enable? > > > @@ -507,7 +526,7 @@ static int ili9882t_prepare(struct drm_panel *panel) > > > gpiod_set_value(ili->enable_gpio, 1); > > > usleep_range(1000, 2000); > > > gpiod_set_value(ili->enable_gpio, 0); > > > - usleep_range(1000, 2000); > > > + usleep_range(40000, 50000); > > > > nit: use 40000, 41000 instead of 40000, 50000. Linux almost always > > uses the longer delay, so that'll save ~9 ms. The only reason for the > > range is to optimize kernel wakeups which is really not a concern > > here. > > We need 50ms delay to meet the requirement. I'll respond to your v2, but if you need 50 ms then your current delay is wrong. -Doug
