Re: [PATCH] Documentation: dt: mtd: replace "nor-jedec" binding with "jedec,spi-nor"

[Brian Norris <computersforpeace@gmail.com>]

It really helps if I test patches...

On Thu, May 14, 2015 at 10:32:53AM -0700, Brian Norris wrote:
> In commit 8ff16cf77ce3 ("Documentation: devicetree: m25p80: add "nor-jedec"
> binding"), we added a generic "nor-jedec" binding to catch all
> mostly-compatible SPI NOR flash which can be detected via the READ ID
> opcode (0x9F). This was discussed and reviewed at the time, however
> objections have come up since then as part of this discussion:
> 
>   http://lkml.kernel.org/g/20150511224646.GJ32500@ld-irv-0074
> 
> It seems the parties involved agree that "jedec,spi-nor" does a better
> job of capturing the fact that this is SPI-specific, not just any NOR
> flash.
> 
> This binding was only merged for v4.1-rc1, so it's still OK to change
> the naming.
> 
> At the same time, let's move the documentation to a better name.
> 
> Next up: prune the m25p_ids[] table to the minimal necessary listing, so
> we can stop referring to code (drivers/mtd/devices/m25p80.c) from the
> documentation.
> 
> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Rafał Miłecki <zajec5@gmail.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> Cc: Kumar Gala <galak@codeaurora.org>
> Cc: devicetree@vger.kernel.org
> ---
> I'd *really* like to get an 'ack' from a DT maintainer for this, those those
> are apparently very hard to come by. And I'd really not like to have to revisit
> this again in a few weeks. We have patches getting queued up for 4.2 that are
> using the "nor-jedec" binding, and I'd like to nip those in the bud ASAP.
> 
>  .../devicetree/bindings/mtd/{m25p80.txt => jedec,spi-nor.txt}       | 6 +++---
>  drivers/mtd/devices/m25p80.c                                        | 6 +++---
>  2 files changed, 6 insertions(+), 6 deletions(-)
>  rename Documentation/devicetree/bindings/mtd/{m25p80.txt => jedec,spi-nor.txt} (85%)
> 
...
> diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
> index 7c8b1694a134..3d59ebc16b6e 100644
> --- a/drivers/mtd/devices/m25p80.c
> +++ b/drivers/mtd/devices/m25p80.c
> @@ -223,7 +223,7 @@ static int m25p_probe(struct spi_device *spi)
>  	 */
>  	if (data && data->type)
>  		flash_name = data->type;
> -	else if (!strcmp(spi->modalias, "nor-jedec"))
> +	else if (!strcmp(spi->modalias, "jedec,spi-nor"))
>  		flash_name = NULL; /* auto-detect */
>  	else
>  		flash_name = spi->modalias;
> @@ -255,7 +255,7 @@ static int m25p_remove(struct spi_device *spi)
>   * since most of these flash are compatible to some extent, and their
>   * differences can often be differentiated by the JEDEC read-ID command, we
>   * encourage new users to add support to the spi-nor library, and simply bind
> - * against a generic string here (e.g., "nor-jedec").
> + * against a generic string here (e.g., "jedec,spi-nor").
>   *
>   * Many flash names are kept here in this list (as well as in spi-nor.c) to
>   * keep them available as module aliases for existing platforms.
> @@ -305,7 +305,7 @@ static const struct spi_device_id m25p_ids[] = {
>  	 * Generic support for SPI NOR that can be identified by the JEDEC READ
>  	 * ID opcode (0x9F). Use this, if possible.
>  	 */
> -	{"nor-jedec"},
> +	{"jedec,spi-nor"},

So I forgot (again; we hit this before) that the SPI/OF framework strips
everything before the first comma before binding devices. See
of_modalias_node(). So I'll have to squash in the patch below to get a
usable binding.

>  	{ },
>  };
>  MODULE_DEVICE_TABLE(spi, m25p_ids);

This patch will make the code bind against anything like
"<foo>,spi-nor", but we'll leave the comment to recommend
using "jedec,spi-nor".

Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 3d59ebc16b6e..3af137f49ac9 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -223,7 +223,7 @@ static int m25p_probe(struct spi_device *spi)
 	 */
 	if (data && data->type)
 		flash_name = data->type;
-	else if (!strcmp(spi->modalias, "jedec,spi-nor"))
+	else if (!strcmp(spi->modalias, "spi-nor"))
 		flash_name = NULL; /* auto-detect */
 	else
 		flash_name = spi->modalias;
@@ -305,7 +305,7 @@ static const struct spi_device_id m25p_ids[] = {
 	 * Generic support for SPI NOR that can be identified by the JEDEC READ
 	 * ID opcode (0x9F). Use this, if possible.
 	 */
-	{"jedec,spi-nor"},
+	{"spi-nor"},
 	{ },
 };
 MODULE_DEVICE_TABLE(spi, m25p_ids);