[PATCH V2] Add support for flag status register on Micron chips.

[Harini Katakam]

Hi,

On Fri, Apr 11, 2014 at 8:33 PM,  <grmoore at altera.com> wrote:
> From: Graham Moore <grmoore at altera.com>
>
> Some new Micron flash chips require reading the flag
> status register to determine when operations have completed.
>
> Furthermore, chips with multi-die stacks of the 65nm 256Mb QSPI also
> require reading the status register before reading the flag status register.
>
> This patch adds support for the flag status register in the n25q512a1 and n25q00
> Micron QSPI flash chips.
>
> Signed-off-by: Graham Moore <grmoore at altera.com>

<snip>

>  #define INFO(_jedec_id, _ext_id, _sector_size, _n_sectors, _flags)     \
> @@ -941,6 +999,8 @@ static const struct spi_device_id m25p_ids[] = {
>         { "n25q128a13",  INFO(0x20ba18, 0, 64 * 1024,  256, 0) },
>         { "n25q256a",    INFO(0x20ba19, 0, 64 * 1024,  512, SECT_4K) },
>         { "n25q512a",    INFO(0x20bb20, 0, 64 * 1024, 1024, SECT_4K) },
> +       { "n25q512a1",   INFO(0x20ba20, 0, 64 * 1024, 1024, USE_FSR) },
> +       { "n25q00",      INFO(0x20ba21, 0, 64 * 1024, 2048, USE_FSR) },
>

I understand that "n25q512a1" was added to distinguish between
0x20bb20 and 0x20ba20,
which is essentially 1.8V and 3V parts.
(The actual part numbers are n25q512a11 and n25q512a13 respectively)
But USE_FSR is required for both parts.

Sorry for posting this question here but it seemed relevant:
When such devices differ only in supply voltages (and return different
response to READ ID),
which we don't act on, is there a way to use the same string?

Regards,
Harini