Click here to Skip to main content
15,843,727 members
Please Sign up or sign in to vote.
1.00/5 (1 vote)
See more:
hi all,

I am working in linux device driver, i have seen a macro DMA_BIT_MASK(32), can any one tell me function of this macro in kernel



Thanks,
shan

[edit]SHOUTING removed - OriginalGriff[/edit]
Posted
Updated 3-Jul-13 5:55am
v2
Comments
OriginalGriff 3-Jul-13 10:55am    
DON'T SHOUT. Using all capitals is considered shouting on the internet, and rude (using all lower case is considered childish). Use proper capitalisation if you want to be taken seriously.

1 solution

Google is your friend: Be nice and visit him often. He can answer questions a lot more quickly than posting them here...

A very quick search using just DMA_BIT_MASK as the search term gave 23,000 hits: Google DMA_BIT_MASK[^]

The top hit took me to Linux Crsoss reference, http://lxr.free-electrons.com/ident?v=2.6.34;i=DMA_BIT_MASK[^] which links to the definition: http://lxr.free-electrons.com/source/include/linux/dma-mapping.h?v=2.6.34#L65[^] which shows the whole macro.

A quick glance tells you exactly what it does! I.e. converts a bit number to a bit mask.

In future, please try to do at least basic research yourself, and not waste your time or ours.
 
Share this answer
 

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)



CodeProject, 20 Bay Street, 11th Floor Toronto, Ontario, Canada M5J 2N8 +1 (416) 849-8900