6.10-stable review patch. If anyone has any objections, please let me know.
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From: Joy Chakraborty joychakr@google.com
commit fc82336b50e7652530bc32caec80be0f8792513b upstream.
Read callbacks registered with nvmem core expect 0 to be returned on success and a negative value to be returned on failure.
abx80x_nvmem_xfer() on read calls i2c_smbus_read_i2c_block_data() which returns the number of bytes read on success as per its api description, this return value is handled as an error and returned to nvmem even on success.
Fix to handle all possible values that would be returned by i2c_smbus_read_i2c_block_data().
Fixes: e90ff8ede777 ("rtc: abx80x: Add nvmem support") Cc: stable@vger.kernel.org Signed-off-by: Joy Chakraborty joychakr@google.com Reviewed-by: Dan Carpenter dan.carpenter@linaro.org Reviewed-by: Sean Anderson sean.anderson@seco.com Link: https://lore.kernel.org/r/20240613120750.1455209-1-joychakr@google.com Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rtc/rtc-abx80x.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
--- a/drivers/rtc/rtc-abx80x.c +++ b/drivers/rtc/rtc-abx80x.c @@ -705,14 +705,18 @@ static int abx80x_nvmem_xfer(struct abx8 if (ret) return ret;
- if (write) + if (write) { ret = i2c_smbus_write_i2c_block_data(priv->client, reg, len, val); - else + if (ret) + return ret; + } else { ret = i2c_smbus_read_i2c_block_data(priv->client, reg, len, val); - if (ret) - return ret; + if (ret <= 0) + return ret ? ret : -EIO; + len = ret; + }
offset += len; val += len;