Re: [PATCH v3 1/3] mtd: nand: gpmi: add gpmi_move_bits function

[Huang Shijie <shijie8@gmail.com>]

On Tue, Sep 23, 2014 at 04:07:34PM +0200, Boris BREZILLON wrote:
> Add a new function to move bits (not bytes) from a memory region to
> another one.
> This function is similar to memmove except it acts at bit level.
> This function is needed to implement GPMI raw access functions, given the
> fact that ECC engine does not pad ECC bits to the next byte boundary.
sorry for not comment your v2 patch set.

> 
> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
> ---
>  drivers/mtd/nand/gpmi-nand/gpmi-lib.c  | 88 ++++++++++++++++++++++++++++++++++
>  drivers/mtd/nand/gpmi-nand/gpmi-nand.h |  4 ++
>  2 files changed, 92 insertions(+)
> 
> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
> index 87e658c..e2f706a 100644
> --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
> @@ -1353,3 +1353,91 @@ int gpmi_read_page(struct gpmi_nand_data *this,
>  	set_dma_type(this, DMA_FOR_READ_ECC_PAGE);
>  	return start_dma_with_bch_irq(this, desc);
>  }
> +
> +void gpmi_move_bits(u8 *dst, size_t dst_bit_off,
> +		    const u8 *src, size_t src_bit_off,
> +		    size_t nbits)
we can simplify the code.

We could use the bytes to replace the @nbits.

The chunk data is always byte aligned.


Btw: please add more comments in this function.

thanks
Huang Shijie