| Message ID | 20240613120750.1455209-1-joychakr@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] rtc: abx80x: Fix return value of nvmem callback on read | expand |
On Thu, Jun 13, 2024 at 12:07:50PM +0000, Joy Chakraborty wrote: > 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> Thanks! Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> regards, dan carpenter
On 6/13/24 08:07, Joy Chakraborty wrote: > 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. Humm, I wish this were documented in nvmem-provider.h... > 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> > --- > drivers/rtc/rtc-abx80x.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c > index fde2b8054c2e..1298962402ff 100644 > --- a/drivers/rtc/rtc-abx80x.c > +++ b/drivers/rtc/rtc-abx80x.c > @@ -705,14 +705,18 @@ static int abx80x_nvmem_xfer(struct abx80x_priv *priv, unsigned int offset, > 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; Reviewed-by: Sean Anderson <sean.anderson@seco.com>
diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c index fde2b8054c2e..1298962402ff 100644 --- a/drivers/rtc/rtc-abx80x.c +++ b/drivers/rtc/rtc-abx80x.c @@ -705,14 +705,18 @@ static int abx80x_nvmem_xfer(struct abx80x_priv *priv, unsigned int offset, 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;
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> --- drivers/rtc/rtc-abx80x.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)