Elise Lennion 57499d136e staging: sm750fb: Refine the code and remove unused code.
Every call to the function waitNextVerticalSync() used the macro
primaryWaitVerticalSync(), so the macro was removed and the function
waitNextVerticalSync() renamed to primary_wait_vertical_sync().

With this change, an unnecessary 'if' statement was removed together
with the lines within the 'else' statement, because it was never
satisfied.

The modified function was refined to better match the Kernel coding
style.

Signed-off-by: Elise Lennion <elise.lennion@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27 15:19:37 +02:00
..
2016-02-07 18:53:35 -08:00

Introduction:
	SM750 of Silicon MOtion is pci express display controller device.
	The SM750 embedded graphics features include:
	- dual display
	- 2D acceleration
	- 16MB integrated video memory

About the kernel module parameter of driver:

	Use 1280,8bpp index color and 60 hz mode:
	insmod ./sm750fb.ko g_option="1280x1024-8@60"

	Disable MTRR,Disable 2d acceleration,Disable hardware cursor,
	and use a 800x600 mode :
	insmod ./sm750fb.ko g_option="noaccel:nomtrr:nohwc:800x600"

	dual frame buffer for driver with "dual" parameter
	insmod ./sm750fb.ko g_option="dual,800x600:1024x768"
	it will create fb0 and fb1 (or fb1,fb2 if fb0 already exist) under /dev
	and user can use con2fb to link fbX and ttyX

	Notes:
	1) if you build the driver with built-in method, the parameter
		you edited in the grub config file will be also the
		same format as above modular method,but additionally add
		"video=sm750fb:"
		ahead of parameters,so,it looks like:
		video=sm750fb:noaccel,1280x1024@60,otherparam,etc...
		it equal to modular method with below command:
		insmod ./sm750fb.ko g_option="noaccel:1280x1024@60:otherparm:etc..."

	2) if you put 800x600 into the parameter without bpp and
		refresh rate, kernel driver will defaulty use 16bpp and 60hz

Important:
	if you have vesafb enabled in your config then /dev/fb0 will be created by vesafb
	and this driver will use fb1, fb2. In that case, you need to configure your X-server
	to use fb1. Another simple althernative is to disable vesafb from your config.