[PATCH v2 3/4] mtd: mchp23k256: add partitioning support

[Chris Packham]

Setting the of_node for the mtd device allows the generic mtd code to
setup the partitions. Additionally we must specify a non-zero erasesize
for the partitions to be writeable.

Signed-off-by: Chris Packham <chris.packham at alliedtelesis.co.nz>
Reviewed-by: Andrew Lunn <andrew at lunn.ch>
Tested-by: Andrew Lunn <andrew at lunn.ch>
---
Changes in v2
- collect revew/test from Andrew

 drivers/mtd/devices/mchp23k256.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c
index 2542f5b8b63f..02c6b9dcbd3e 100644
--- a/drivers/mtd/devices/mchp23k256.c
+++ b/drivers/mtd/devices/mchp23k256.c
@@ -143,6 +143,7 @@ static int mchp23k256_probe(struct spi_device *spi)
 
 	data = dev_get_platdata(&spi->dev);
 
+	mtd_set_of_node(&flash->mtd, spi->dev.of_node);
 	flash->mtd.dev.parent	= &spi->dev;
 	flash->mtd.type		= MTD_RAM;
 	flash->mtd.flags	= MTD_CAP_RAM;
@@ -151,6 +152,10 @@ static int mchp23k256_probe(struct spi_device *spi)
 	flash->mtd._read	= mchp23k256_read;
 	flash->mtd._write	= mchp23k256_write;
 
+	flash->mtd.erasesize = PAGE_SIZE;
+	while (flash->mtd.size & (flash->mtd.erasesize - 1))
+		flash->mtd.erasesize >>= 1;
+
 	err = mtd_device_register(&flash->mtd, data ? data->parts : NULL,
 				  data ? data->nr_parts : 0);
 	if (err)
-- 
2.11.0.24.ge6920cf