| Message ID | 20240605175953.2613260-2-joychakr@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | nvmem: Handle change of return type in reg_read/write() definition | expand |
On 6/5/24 10:59, Joy Chakraborty wrote: > Change nvmem read/write function definition return type to ssize_t. > > Signed-off-by: Joy Chakraborty <joychakr@google.com> > --- > drivers/hwmon/pmbus/adm1266.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c > index 2c4d94cc8729..7eaab5a7b04c 100644 > --- a/drivers/hwmon/pmbus/adm1266.c > +++ b/drivers/hwmon/pmbus/adm1266.c > @@ -375,7 +375,7 @@ static int adm1266_nvmem_read_blackbox(struct adm1266_data *data, u8 *read_buff) > return 0; > } > > -static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > +static ssize_t adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > { > struct adm1266_data *data = priv; > int ret; > @@ -395,7 +395,7 @@ static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t > > memcpy(val, data->dev_mem + offset, bytes); > > - return 0; > + return bytes; > } > > static int adm1266_config_nvmem(struct adm1266_data *data) The series doesn't explain what a driver is supposed to do if it only transfers part of the data but not all of it due to an error, or because the request exceeded the size of the media. For example, this driver still returns an error code if it successfully transferred some data but not all of it, or if more data was requested than is available. I didn't check other drivers, but I would assume that many of them have the same or a similar problem. Guenter
On Wed, Jun 05, 2024 at 05:59:45PM +0000, Joy Chakraborty wrote: > Change nvmem read/write function definition return type to ssize_t. > > Signed-off-by: Joy Chakraborty <joychakr@google.com> > --- > drivers/hwmon/pmbus/adm1266.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c > index 2c4d94cc8729..7eaab5a7b04c 100644 > --- a/drivers/hwmon/pmbus/adm1266.c > +++ b/drivers/hwmon/pmbus/adm1266.c > @@ -375,7 +375,7 @@ static int adm1266_nvmem_read_blackbox(struct adm1266_data *data, u8 *read_buff) > return 0; > } > > -static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > +static ssize_t adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > { > struct adm1266_data *data = priv; > int ret; > @@ -395,7 +395,7 @@ static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t > > memcpy(val, data->dev_mem + offset, bytes); > > - return 0; > + return bytes; > } This breaks the build so it's not allowed. The way to do it is to: 1) add a new pointer which takes a ssize_t 2) convert everything to the new pointer 3) Rename the new pointer to the old name regards, dan carpenter
On Thu, Jun 6, 2024 at 2:59 AM Guenter Roeck <linux@roeck-us.net> wrote: > > On 6/5/24 10:59, Joy Chakraborty wrote: > > Change nvmem read/write function definition return type to ssize_t. > > > > Signed-off-by: Joy Chakraborty <joychakr@google.com> > > --- > > drivers/hwmon/pmbus/adm1266.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c > > index 2c4d94cc8729..7eaab5a7b04c 100644 > > --- a/drivers/hwmon/pmbus/adm1266.c > > +++ b/drivers/hwmon/pmbus/adm1266.c > > @@ -375,7 +375,7 @@ static int adm1266_nvmem_read_blackbox(struct adm1266_data *data, u8 *read_buff) > > return 0; > > } > > > > -static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > > +static ssize_t adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) > > { > > struct adm1266_data *data = priv; > > int ret; > > @@ -395,7 +395,7 @@ static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t > > > > memcpy(val, data->dev_mem + offset, bytes); > > > > - return 0; > > + return bytes; > > } > > > > static int adm1266_config_nvmem(struct adm1266_data *data) > > The series doesn't explain what a driver is supposed to do if it > only transfers part of the data but not all of it due to an error, > or because the request exceeded the size of the media. > This patch series is actually a follow up on https://lore.kernel.org/all/20240206042408.224138-1-joychakr@google.com/ which has now been reverted . I shall try to collate it and send it again with a better explanation. > For example, this driver still returns an error code if it successfully > transferred some data but not all of it, or if more data was requested > than is available. > > I didn't check other drivers, but I would assume that many of them > have the same or a similar problem. > > Guenter >
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c index 2c4d94cc8729..7eaab5a7b04c 100644 --- a/drivers/hwmon/pmbus/adm1266.c +++ b/drivers/hwmon/pmbus/adm1266.c @@ -375,7 +375,7 @@ static int adm1266_nvmem_read_blackbox(struct adm1266_data *data, u8 *read_buff) return 0; } -static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) +static ssize_t adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes) { struct adm1266_data *data = priv; int ret; @@ -395,7 +395,7 @@ static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t memcpy(val, data->dev_mem + offset, bytes); - return 0; + return bytes; } static int adm1266_config_nvmem(struct adm1266_data *data)
Change nvmem read/write function definition return type to ssize_t. Signed-off-by: Joy Chakraborty <joychakr@google.com> --- drivers/hwmon/pmbus/adm1266.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)