Re: [PATCH] mtd: spi-nor: read 6 bytes for the ID

Huang Shijie
2014-05-27T02:33:28Z

On Mon, Apr 14, 2014 at 06:09:34PM +0800, Huang Shijie wrote:
> Currently, we read 5 bytes for ID, but s25fl128s has the same ext_id(0x4d01)
> with s25fl129p1. The s25fl128s can support the DDR Quad read, while s25fl129p1
> does not. So we have to distinguish the two NOR flashs.
>
> This patch reads out 6 bytes for the ID, and use the 6 bytes ID to search the
> right flash_info.
>
> The detail of the patch is:
> [1] change the "ext_id" from u16 to u32.
> We can store two bytes or three bytes with the @ext_id now.
>
> [2] search the right flash_info with the 6byte ID and the new @ext_id.
> We use "matched" variable to track the legacy two bytes @ext_id.
> If the flash_info's @ext_id is three bytes, we will use the
> sixth byte of the ID to check it.
>
> [3] add the new item to spi_nor_ids for s25fl128s.
>
> Signed-off-by: Huang Shijie <b32955@freescale.com>
> ---
> based on Brian's patch set.
> ---
> drivers/mtd/spi-nor/spi-nor.c | 27 ++++++++++++++++++++++-----
> 1 files changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index d6f44d5..cd4b277 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -383,7 +383,7 @@ struct flash_info {
> * then a two byte device id.
> */
> u32 jedec_id;
> - u16 ext_id;
> + u32 ext_id;
>
> /* The size listed here is what works with SPINOR_OP_SE, which isn't
> * necessarily called a "sector" by the vendor.
> @@ -505,6 +505,7 @@ const struct spi_device_id spi_nor_ids[] = {
> { "s70fl01gs", INFO(0x010221, 0x4d00, 256 * 1024, 256, 0) },
> { "s25sl12800", INFO(0x012018, 0x0300, 256 * 1024, 64, 0) },
> { "s25sl12801", INFO(0x012018, 0x0301, 64 * 1024, 256, 0) },
> + { "s25fl128s", INFO(0x012018, 0x4d0180, 64 * 1024, 256, SPI_NOR_QUAD_READ) },
> { "s25fl129p0", INFO(0x012018, 0x4d00, 256 * 1024, 64, 0) },
> { "s25fl129p1", INFO(0x012018, 0x4d01, 64 * 1024, 256, 0) },
> { "s25sl004a", INFO(0x010212, 0, 64 * 1024, 8, 0) },
> @@ -593,12 +594,13 @@ EXPORT_SYMBOL_GPL(spi_nor_ids);
> static const struct spi_device_id *spi_nor_read_id(struct spi_nor *nor)
> {
> int tmp;
> - u8 id[5];
> + u8 id[6];
> u32 jedec;
> - u16 ext_jedec;
> + u32 ext_jedec;
> struct flash_info *info;
> + int matched = -1;
>
> - tmp = nor->read_reg(nor, SPINOR_OP_RDID, id, 5);
> + tmp = nor->read_reg(nor, SPINOR_OP_RDID, id, 6);
> if (tmp < 0) {
> dev_dbg(nor->dev, " error %d reading JEDEC ID\n", tmp);
> return ERR_PTR(tmp);
> @@ -614,8 +616,23 @@ static const struct spi_device_id *spi_nor_read_id(struct spi_nor *nor)
> for (tmp = 0; tmp < ARRAY_SIZE(spi_nor_ids) - 1; tmp++) {
> info = (void *)spi_nor_ids[tmp].driver_data;
> if (info->jedec_id == jedec) {
> - if (info->ext_id == 0 || info->ext_id == ext_jedec)
> + if (info->ext_id == 0)
> return &spi_nor_ids[tmp];
> +
> + /* the legacy two bytes ext_id */
> + if ((info->ext_id >> 16) == 0) {
> + if (info->ext_id == ext_jedec)
> + matched = tmp;
> + } else {
> + /* check the sixth byte now */
> + ext_jedec = ext_jedec << 8 | id[5];
> + if (info->ext_id == ext_jedec)
> + return &spi_nor_ids[tmp];
> + }
> + } else {
> + /* shortcut */
> + if (matched != -1)
> + return &spi_nor_ids[matched];
> }
> }
> dev_err(nor->dev, "unrecognized JEDEC id %06x\n", jedec);
Hi Brian:
any comment about this patch?

thanks
Huang Shijie