[RFC PATCH 22/27] mtd: spinand: Let the SPI-NAND core flag a SPI-NAND chip

From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Boris Brezillon <bbrezillon@kernel.org>,
	Richard Weinberger <richard@nod.at>,
	David Woodhouse <dwmw2@infradead.org>,
	Brian Norris <computersforpeace@gmail.com>,
	Marek Vasut <marek.vasut@gmail.com>,
	Tudor Ambarus <Tudor.Ambarus@microchip.com>
Cc: Vignesh R <vigneshr@ti.com>,
	Tudor Ambarus <tudor.ambarus@microchip.com>,
	Julien Su <juliensu@mxic.com.tw>,
	Schrempf Frieder <frieder.schrempf@kontron.de>,
	linux-mtd@lists.infradead.org,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Mason Yang <masonccyang@mxic.com.tw>,
	linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH 22/27] mtd: spinand: Let the SPI-NAND core flag a SPI-NAND chip
Date: Thu, 21 Feb 2019 13:58:01 +0100	[thread overview]
Message-ID: <20190221125806.28875-10-miquel.raynal@bootlin.com> (raw)
In-Reply-To: <20190221125806.28875-1-miquel.raynal@bootlin.com>

As of today there is no way to make the distinction between a raw NAND
chip and a SPI-NAND chip. The ABI is stable and we cannot add a
"SPI-NAND" tag to the MTD type, but we can add a special SPINAND
capability to the flags instead. A helper is also provided to retrieve
if whether or not the chip is working over SPI or not.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/core.c    | 2 +-
 include/linux/mtd/mtd.h    | 5 +++++
 include/uapi/mtd/mtd-abi.h | 1 +
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/core.c b/drivers/mtd/nand/core.c
index a76d206d233a..872d46b5fc0f 100644
--- a/drivers/mtd/nand/core.c
+++ b/drivers/mtd/nand/core.c
@@ -245,7 +245,7 @@ int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
 
 	mtd->type = memorg->bits_per_cell == 1 ?
 		    MTD_NANDFLASH : MTD_MLCNANDFLASH;
-	mtd->flags = MTD_CAP_NANDFLASH;
+	mtd->flags = MTD_SPINAND | MTD_CAP_NANDFLASH;
 	mtd->erasesize = memorg->pagesize * memorg->pages_per_eraseblock;
 	mtd->writesize = memorg->pagesize;
 	mtd->writebufsize = memorg->pagesize;
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 677768b21a1d..7c245d109524 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -551,6 +551,11 @@ static inline int mtd_type_is_nand(const struct mtd_info *mtd)
 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
 }
 
+static inline int mtd_type_is_spinand(const struct mtd_info *mtd)
+{
+	return mtd_type_is_nand(mtd) && (mtd->flags & MTD_SPINAND);
+}
+
 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
 {
 	return !!mtd->_block_isbad;
diff --git a/include/uapi/mtd/mtd-abi.h b/include/uapi/mtd/mtd-abi.h
index aff5b5e59845..7c7124c88fe0 100644
--- a/include/uapi/mtd/mtd-abi.h
+++ b/include/uapi/mtd/mtd-abi.h
@@ -104,6 +104,7 @@ struct mtd_write_req {
 #define MTD_BIT_WRITEABLE	0x800	/* Single bits can be flipped */
 #define MTD_NO_ERASE		0x1000	/* No erase necessary */
 #define MTD_POWERUP_LOCK	0x2000	/* Always locked after reset */
+#define MTD_SPINAND		0x4000	/* Device works over SPI */
 
 /* Some common devices / combinations of capabilities */
 #define MTD_CAP_ROM		0
-- 
2.19.1


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