driver: Ensure to call set_tear_on on CMD mode panels

The downstream msm-4.9 driver is unconditinally calling
mdss_dsi_set_tear_on with command mode panels, replicate the same in the
driver generator, but only add the call if it hasn't already been
present in the commands, as is seen on some panels.

When this doesn't get enabled then the panel doesn't generate any
Tearing Effect output signal which is used by MDSS.

Author: z3ntu

driver.py

@@ -7,7 +7,7 @@
 import simple
 import wrap
 from generator import Options, GpioFlag
-from panel import Panel, BacklightControl, CommandSequence, CompressionMode
+from panel import Panel, BacklightControl, CommandSequence, CompressionMode, Mode
 
 
 def generate_includes(p: Panel, options: Options) -> str:
@@ -158,6 +158,14 @@ def generate_commands(p: Panel, options: Options, cmd_name: str) -> str:
 		if c.wait and c.wait > options.ignore_wait:
 			s += f'\t{dsi_msleep(c.wait)};\n'
 
+
+	if cmd_name == 'on' and p.mode == Mode.CMD_MODE:
+		has_tear_on = any("set_tear_on" in c.generated for c in cmd.seq)
+		if not has_tear_on:
+			s += '''
+	mipi_dsi_dcs_set_tear_on_multi(&dsi_ctx, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
+'''
+
 	s += '''
 	return dsi_ctx.accum_err;
 }