From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Norris Subject: [PATCH 1/2] Documentation: devicetree: m25p80: add "nor-jedec" binding Date: Wed, 11 Mar 2015 14:57:25 -0700 Message-ID: <1426111046-29900-1-git-send-email-computersforpeace@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ezequiel Garcia , Brian Norris , Marek Vasut , =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= List-Id: devicetree@vger.kernel.org Almost all flash that are "compatible" with m25p80 support the JEDEC READ ID opcode (0x95), and in fact, that is often the only thing that i= s used to differentiate them. Let's add a compatible string that represents this lowest common denominator of compatibility. Device trees can still specify manufacturer/device names in addition, but (until some reason is found to differentiate between them through device tree) software will likely want to bind just against the generic name, and avoid unnecessarily growing its device ID binding tables. This is related to the work of commit a5b7616c55e1 ("mtd: m25p80,spi-nor: Fix module aliases for m25p80"), which showed that maintaining these device tables as stable device-tree/modalias binding tables is not a worthwhile burden for mostly-comptatible flash. At the same time, let's update the binding doc to point to the m25p_ids[] ID list instead of spi_nor_ids[]. The former can be used for device tree bindings, but the latter cannot. In the future, we should pare down the m25p_ids[] list to only those IDs which are actually used in device trees. Signed-off-by: Brian Norris Cc: Rafa=C5=82 Mi=C5=82ecki --- Documentation/devicetree/bindings/mtd/m25p80.txt | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/mtd/m25p80.txt b/Documen= tation/devicetree/bindings/mtd/m25p80.txt index 4611aa83531b..1b2997d4cee4 100644 --- a/Documentation/devicetree/bindings/mtd/m25p80.txt +++ b/Documentation/devicetree/bindings/mtd/m25p80.txt @@ -3,9 +3,12 @@ Required properties: - #address-cells, #size-cells : Must be present if the device has sub-= nodes representing partitions. -- compatible : Should be the manufacturer and the name of the chip. Be= ar in mind +- compatible : Should be "nor-jedec" for any SPI NOR flash that can be + identified by the JEDEC READ ID opcode (0x95). + Additionally, may include a device-specific string cons= isting of + the manufacturer and name of the chip. Bear in mind the DT binding is not Linux-only, but in case of Linux,= see the - "spi_nor_ids" table in drivers/mtd/spi-nor/spi-nor.c fo= r the list + "m25p_ids" table in drivers/mtd/devices/m25p80.c for th= e list of supported chips. - reg : Chip-Select number - spi-max-frequency : Maximum frequency of the SPI bus the chip can op= erate at @@ -22,7 +25,7 @@ Example: flash: m25p80@0 { #address-cells =3D <1>; #size-cells =3D <1>; - compatible =3D "spansion,m25p80"; + compatible =3D "spansion,m25p80", "nor-jedec"; reg =3D <0>; spi-max-frequency =3D <40000000>; m25p,fast-read; --=20 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html