Re: [PATCH V2 0/4] mtd: gpmi: support two nand chips at most

[Huang Shijie <b32955@freescale.com>]

于 2013年08月27日 17:29, Huang Shijie 写道:
> 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.) 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.
>
> To Brian:
> 	My "better" solution was proved to be a bad idea. So i resend this
> 	patch set again.
>
> v1 --> v2:
> 	[0] rebase on the latest l2-mtd tree.
>
> 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  |   13 +++++++++++++
>  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |    7 +++----
>  drivers/mtd/nand/gpmi-nand/gpmi-regs.h |    3 +++
>  3 files changed, 19 insertions(+), 4 deletions(-)
>
just a ping