[PATCH v7 04/10] mtd: mtk-quadspi: return amount of data transferred or error in read/write

From: Brian Norris
Date: Thu May 05 2016 - 20:34:20 EST


Add checking of SPI transfer errors and return them from read/write
functions. Also return the amount of data transferred.

Signed-off-by: Brian Norris <computersforpeace@xxxxxxxxx>
---
New in v7

drivers/mtd/spi-nor/mtk-quadspi.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c
index ab92ac0f6b2b..e85687126c25 100644
--- a/drivers/mtd/spi-nor/mtk-quadspi.c
+++ b/drivers/mtd/spi-nor/mtk-quadspi.c
@@ -261,7 +261,7 @@ static ssize_t mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t length,
return ret;
buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG);
}
- return 0;
+ return length;
}

static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor,
@@ -302,6 +302,7 @@ static ssize_t mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
{
int ret;
struct mt8173_nor *mt8173_nor = nor->priv;
+ size_t i;

ret = mt8173_nor_write_buffer_enable(mt8173_nor);
if (ret < 0) {
@@ -309,13 +310,12 @@ static ssize_t mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
return ret;
}

- while (len >= SFLASH_WRBUF_SIZE) {
+ for (i = 0; i + SFLASH_WRBUF_SIZE <= len; i += SFLASH_WRBUF_SIZE) {
ret = mt8173_nor_write_buffer(mt8173_nor, to, buf);
if (ret < 0) {
dev_err(mt8173_nor->dev, "write buffer failed!\n");
return ret;
}
- len -= SFLASH_WRBUF_SIZE;
to += SFLASH_WRBUF_SIZE;
buf += SFLASH_WRBUF_SIZE;
(*retlen) += SFLASH_WRBUF_SIZE;
@@ -326,9 +326,9 @@ static ssize_t mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
return ret;
}

- if (len) {
- ret = mt8173_nor_write_single_byte(mt8173_nor, to, (int)len,
- (u8 *)buf);
+ if (i < len) {
+ ret = mt8173_nor_write_single_byte(mt8173_nor, to,
+ (int)(len - i), (u8 *)buf);
if (ret < 0) {
dev_err(mt8173_nor->dev, "write single byte failed!\n");
return ret;
@@ -336,7 +336,7 @@ static ssize_t mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
(*retlen) += len;
}

- return 0;
+ return len;
}

static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
--
2.8.0.rc3.226.g39d4020