* Query about Linux framebuffer implementation
@ 2010-03-09 7:58 胡杨树
2010-03-09 9:04 ` Russell King - ARM Linux
0 siblings, 1 reply; 2+ messages in thread
From: 胡杨树 @ 2010-03-09 7:58 UTC (permalink / raw)
To: linux-arm-kernel
Hi, all
driver/video/fbmem.c implement framebuffer as a char device, in read/write API of this char device file operations, WHY does we need to:
1st:kmalloc a space
2st:copy data between video memory buffer and kmalloced space above
3rd:copy kmalloced space data to/from user space buffer
why the hell we just copy data between video memory and user space buffer?
THX
ROCKY
^ permalink raw reply [flat|nested] 2+ messages in thread
* Query about Linux framebuffer implementation
2010-03-09 7:58 Query about Linux framebuffer implementation 胡杨树
@ 2010-03-09 9:04 ` Russell King - ARM Linux
0 siblings, 0 replies; 2+ messages in thread
From: Russell King - ARM Linux @ 2010-03-09 9:04 UTC (permalink / raw)
To: linux-arm-kernel
On Tue, Mar 09, 2010 at 03:58:40PM +0800, ??? wrote:
> Hi, all
>
> driver/video/fbmem.c implement framebuffer as a char device, in read/write API of this char device file operations, WHY does we need to:
> 1st:kmalloc a space
> 2st:copy data between video memory buffer and kmalloced space above
> 3rd:copy kmalloced space data to/from user space buffer
>
> why the hell we just copy data between video memory and user space buffer?
=> framebuffer mailing list (though that seems rather dead), maybe
lkml instead?
^ permalink raw reply [flat|nested] 2+ messages in thread
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2010-03-09 7:58 Query about Linux framebuffer implementation 胡杨树
2010-03-09 9:04 ` Russell King - ARM Linux
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