[PATCH] nvmem: rmem: Fix return value of rmem_read()

[PATCH] nvmem: rmem: Fix return value of rmem_read()

[Joy Chakraborty]

reg_read() callback registered with nvmem core expects an integer error
as a return value but rmem_read() returns the number of bytes read, as a
result error checks in nvmem core fail even when they shouldn't.

Return 0 on success where number of bytes read match the number of bytes
requested and a negative error -EINVAL on all other cases.

Fixes: 5a3fa75a4d9c ("nvmem: Add driver to expose reserved memory as nvmem")
Signed-off-by: Joy Chakraborty <joychakr@google.com>
---
 drivers/nvmem/rmem.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/rmem.c b/drivers/nvmem/rmem.c
index 752d0bf4445e..a74dfa279ff4 100644
--- a/drivers/nvmem/rmem.c
+++ b/drivers/nvmem/rmem.c
@@ -46,7 +46,12 @@ static int rmem_read(void *context, unsigned int offset,
 
 	memunmap(addr);
 
-	return count;
+	if (count != bytes) {
+		dev_err(priv->dev, "Failed read memory (%d)\n", count);
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
 static int rmem_probe(struct platform_device *pdev)
-- 
2.43.0.594.gd9cf4e227d-goog

Re: [PATCH] nvmem: rmem: Fix return value of rmem_read()

[Greg Kroah-Hartman]

On Mon, Feb 05, 2024 at 11:48:26AM +0000, Joy Chakraborty wrote:
> reg_read() callback registered with nvmem core expects an integer error
> as a return value but rmem_read() returns the number of bytes read, as a
> result error checks in nvmem core fail even when they shouldn't.
> 
> Return 0 on success where number of bytes read match the number of bytes
> requested and a negative error -EINVAL on all other cases.
> 
> Fixes: 5a3fa75a4d9c ("nvmem: Add driver to expose reserved memory as nvmem")
> Signed-off-by: Joy Chakraborty <joychakr@google.com>
> ---
>  drivers/nvmem/rmem.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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