[PATCH 0/4] mtd: gpmi: support two nand chips at most

Brian Norris computersforpeace at gmail.com
Sun Aug 11 02:09:21 EDT 2013


On Fri, Jun 14, 2013 at 04:06:21PM +0800, Huang Shijie wrote:
> Current gpmi-nand driver only supports one chips. But we may meet
> some embarrassing situation, such as Micron MT29F32G08QAA.
> This nand chip has two DIEs internally. Each die has its own chip select pin,
> so this chip acts as two nand chips.
> 
> If we only scan one chip, we may find that we only get 2G for this chip,
> but in actually, this chip's size is 4G.
> 
> So scan two chips by default.
> 
> In order to support two nand chips, we have to do the following:
>    1.) We only have one dma channel now, so decouple the chip select
>       from the DMA channel, We can use the dma 0 to access all the nand chips.
> 
>    2.) fix the wrong method of checking the ready/busy status.
>       In the imx6, all the ready/busy pins are binding together, we
>       should check ready/busy status of chip 0 for the all the chips. 
> 
> Tested this patch set with MT29F32G08QAA.
> 
> 
> Huang Shijie (4):
>   mtd: gpmi: decouple the chip select from the DMA channel
>   mtd: gpmi: use DMA channel 0 for all the nand chips
>   mtd: gpmi: scan two nand chips
>   mtd: gpmi: imx6: fix the wrong method for checking ready/busy
> 
>  drivers/mtd/nand/gpmi-nand/gpmi-lib.c  |   14 ++++++++++++++
>  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |    7 +++----
>  drivers/mtd/nand/gpmi-nand/gpmi-regs.h |    3 +++
>  3 files changed, 20 insertions(+), 4 deletions(-)

What's the status on this patch set? It doesn't look like it got merged.
Do you have any testing for this? It looks sane enough to me.

Brian



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