[PATCH v3 2/3] rockchip: efuse: fix misc_read() return values

[John Keeping]

The documentation for misc_read() says:

    Return: number of bytes read if OK (may be 0 if EOF), -ve on error

The Rockchip efuse driver implements this so it should return the number
of bytes read rather than zero on success.  Fix this so that the driver
follows the usual contract for read operations.

Reviewed-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Jonas Karlman <jonas at kwiboo.se>
Signed-off-by: John Keeping <john at metanate.com>
---
v3: unchanged
v2:
- Fix when block_size > 1 by moving the return value to the main
  rockchip_efuse_read() wrapper and leaving the individual
  implementations alone (Jonas)

 drivers/misc/rockchip-efuse.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/rockchip-efuse.c b/drivers/misc/rockchip-efuse.c
index 60931a5131..2f96b79ea4 100644
--- a/drivers/misc/rockchip-efuse.c
+++ b/drivers/misc/rockchip-efuse.c
@@ -73,7 +73,7 @@ static int dump_efuse(struct cmd_tbl *cmdtp, int flag,
 
 	for (i = 0; true; i += sizeof(data)) {
 		ret = misc_read(dev, i, &data, sizeof(data));
-		if (ret < 0)
+		if (ret <= 0)
 			return 0;
 
 		print_buffer(i, data, 1, sizeof(data), sizeof(data));
@@ -238,8 +238,10 @@ static int rockchip_efuse_read(struct udevice *dev, int offset,
 
 	offset += data->offset;
 
-	if (data->block_size <= 1)
-		return data->read(dev, offset, buf, size);
+	if (data->block_size <= 1) {
+		ret = data->read(dev, offset, buf, size);
+		goto done;
+	}
 
 	block_start = offset / data->block_size;
 	block_offset = offset % data->block_size;
@@ -255,7 +257,9 @@ static int rockchip_efuse_read(struct udevice *dev, int offset,
 		memcpy(buf, buffer + block_offset, size);
 
 	free(buffer);
-	return ret;
+
+done:
+	return ret < 0 ? ret : size;
 }
 
 static const struct misc_ops rockchip_efuse_ops = {
-- 
2.40.0