[PATCH] mtd: spi-nor: Support controllers with limited TX FIFO size

From: Yogesh Gaur
Date: Wed Jun 13 2018 - 02:09:52 EST


Some SPI controllers can't write nor->page_size bytes in a single
step because their TX FIFO is too small.

Allow nor->write() to return a size that is smaller than the requested
write size to gracefully handle this case.

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@xxxxxxx>
---
drivers/mtd/spi-nor/spi-nor.c | 7 -------
1 file changed, 7 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 5bfa36e..3e63543 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1431,13 +1431,6 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
goto write_err;
*retlen += written;
i += written;
- if (written != page_remain) {
- dev_err(nor->dev,
- "While writing %zu bytes written %zd bytes\n",
- page_remain, written);
- ret = -EIO;
- goto write_err;
- }
}

write_err:
--
2.7.4

Patch is based on the spi-mem framework[1]
[1]https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git/log/?h=for-4.18