On Sat, 2024-02-24 at 12:32 +0000, Jonathan Cameron wrote:
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> This use of the new cleanup.h scope based freeing infrastructure allows
> us to exit directly from error conditions and in the good path with
> the reference obtained from fwnode_find_reference() (which may be an error
> pointer) automatically released.
>
> Similarly the _scoped() version of device_for_each_child_node()
> removes the need for the manual calling of fwnode_handl_put() in
> paths where the code exits the loop early.
>
> Tidy up some unusual indentation in a dev_dbg() whilst here.
>
> Cc: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
> Cc: Nuno Sá <nuno.sa@xxxxxxxxxx>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> ---
> v5: Add the device_for_each_child_node_scoped() change (Nuno)
> ---
Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
> drivers/iio/temperature/ltc2983.c | 137 +++++++++++-------------------
> 1 file changed, 50 insertions(+), 87 deletions(-)
>
> diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
> index fcb96c44d954..7d5473e7b500 100644
> --- a/drivers/iio/temperature/ltc2983.c
> +++ b/drivers/iio/temperature/ltc2983.c
> @@ -656,7 +656,6 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
> const struct ltc2983_sensor *sensor)
> {
> struct ltc2983_thermocouple *thermo;
> - struct fwnode_handle *ref;
> u32 oc_current;
> int ret;
>
> @@ -703,7 +702,8 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
> return ERR_PTR(-EINVAL);
> }
>
> - ref = fwnode_find_reference(child, "adi,cold-junction-handle", 0);
> + struct fwnode_handle *ref __free(fwnode_handle) =
> + fwnode_find_reference(child, "adi,cold-junction-handle", 0);
> if (IS_ERR(ref)) {
> ref = NULL;
> } else {
> @@ -714,7 +714,7 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
> * the error right away.
> */
> dev_err(&st->spi->dev, "Property reg must be given\n");
> - goto fail;
> + return ERR_PTR(ret);
> }
> }
>
> @@ -725,22 +725,15 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
> thermo->custom = __ltc2983_custom_sensor_new(st, child,
> propname, false,
> 16384, true);
> - if (IS_ERR(thermo->custom)) {
> - ret = PTR_ERR(thermo->custom);
> - goto fail;
> - }
> + if (IS_ERR(thermo->custom))
> + return ERR_CAST(thermo->custom);
> }
>
> /* set common parameters */
> thermo->sensor.fault_handler = ltc2983_thermocouple_fault_handler;
> thermo->sensor.assign_chan = ltc2983_thermocouple_assign_chan;
>
> - fwnode_handle_put(ref);
> return &thermo->sensor;
> -
> -fail:
> - fwnode_handle_put(ref);
> - return ERR_PTR(ret);
> }
>
> static struct ltc2983_sensor *
> @@ -750,14 +743,14 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> struct ltc2983_rtd *rtd;
> int ret = 0;
> struct device *dev = &st->spi->dev;
> - struct fwnode_handle *ref;
> u32 excitation_current = 0, n_wires = 0;
>
> rtd = devm_kzalloc(dev, sizeof(*rtd), GFP_KERNEL);
> if (!rtd)
> return ERR_PTR(-ENOMEM);
>
> - ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
> + struct fwnode_handle *ref __free(fwnode_handle) =
> + fwnode_find_reference(child, "adi,rsense-handle", 0);
> if (IS_ERR(ref)) {
> dev_err(dev, "Property adi,rsense-handle missing or invalid");
> return ERR_CAST(ref);
> @@ -766,7 +759,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> ret = fwnode_property_read_u32(ref, "reg", &rtd->r_sense_chan);
> if (ret) {
> dev_err(dev, "Property reg must be given\n");
> - goto fail;
> + return ERR_PTR(ret);
> }
>
> ret = fwnode_property_read_u32(child, "adi,number-of-wires", &n_wires);
> @@ -787,8 +780,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> break;
> default:
> dev_err(dev, "Invalid number of wires:%u\n", n_wires);
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> }
>
> @@ -798,8 +790,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> if (n_wires == 2 || n_wires == 3) {
> dev_err(dev,
> "Rotation not allowed for 2/3 Wire RTDs");
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1);
> } else {
> @@ -829,16 +820,14 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> "Invalid rsense chann:%d to use in kelvin rsense",
> rtd->r_sense_chan);
>
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
>
> if (sensor->chan < min || sensor->chan > max) {
> dev_err(dev, "Invalid chann:%d for the rtd config",
> sensor->chan);
>
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> } else {
> /* same as differential case */
> @@ -846,8 +835,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> dev_err(&st->spi->dev,
> "Invalid chann:%d for RTD", sensor->chan);
>
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> }
>
> @@ -856,10 +844,8 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> rtd->custom = __ltc2983_custom_sensor_new(st, child,
> "adi,custom-rtd",
> false, 2048, false);
> - if (IS_ERR(rtd->custom)) {
> - ret = PTR_ERR(rtd->custom);
> - goto fail;
> - }
> + if (IS_ERR(rtd->custom))
> + return ERR_CAST(rtd->custom);
> }
>
> /* set common parameters */
> @@ -901,18 +887,13 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
> dev_err(&st->spi->dev,
> "Invalid value for excitation current(%u)",
> excitation_current);
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> }
>
> fwnode_property_read_u32(child, "adi,rtd-curve", &rtd->rtd_curve);
>
> - fwnode_handle_put(ref);
> return &rtd->sensor;
> -fail:
> - fwnode_handle_put(ref);
> - return ERR_PTR(ret);
> }
>
> static struct ltc2983_sensor *
> @@ -921,7 +902,6 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> {
> struct ltc2983_thermistor *thermistor;
> struct device *dev = &st->spi->dev;
> - struct fwnode_handle *ref;
> u32 excitation_current = 0;
> int ret = 0;
>
> @@ -929,7 +909,8 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> if (!thermistor)
> return ERR_PTR(-ENOMEM);
>
> - ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
> + struct fwnode_handle *ref __free(fwnode_handle) =
> + fwnode_find_reference(child, "adi,rsense-handle", 0);
> if (IS_ERR(ref)) {
> dev_err(dev, "Property adi,rsense-handle missing or invalid");
> return ERR_CAST(ref);
> @@ -938,7 +919,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> ret = fwnode_property_read_u32(ref, "reg", &thermistor->r_sense_chan);
> if (ret) {
> dev_err(dev, "rsense channel must be configured...\n");
> - goto fail;
> + return ERR_PTR(ret);
> }
>
> if (fwnode_property_read_bool(child, "adi,single-ended")) {
> @@ -958,8 +939,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> dev_err(&st->spi->dev,
> "Invalid chann:%d for differential thermistor",
> sensor->chan);
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
>
> /* check custom sensor */
> @@ -978,10 +958,8 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> propname,
> steinhart,
> 64, false);
> - if (IS_ERR(thermistor->custom)) {
> - ret = PTR_ERR(thermistor->custom);
> - goto fail;
> - }
> + if (IS_ERR(thermistor->custom))
> + return ERR_CAST(thermistor->custom);
> }
> /* set common parameters */
> thermistor->sensor.fault_handler = ltc2983_common_fault_handler;
> @@ -1005,8 +983,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> LTC2983_SENSOR_THERMISTOR_STEINHART) {
> dev_err(&st->spi->dev,
> "Auto Range not allowed for custom
> sensors\n");
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> thermistor->excitation_current = 0x0c;
> break;
> @@ -1047,16 +1024,11 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
> dev_err(&st->spi->dev,
> "Invalid value for excitation current(%u)",
> excitation_current);
> - ret = -EINVAL;
> - goto fail;
> + return ERR_PTR(-EINVAL);
> }
> }
>
> - fwnode_handle_put(ref);
> return &thermistor->sensor;
> -fail:
> - fwnode_handle_put(ref);
> - return ERR_PTR(ret);
> }
>
> static struct ltc2983_sensor *
> @@ -1349,8 +1321,7 @@ static irqreturn_t ltc2983_irq_handler(int irq, void *data)
> static int ltc2983_parse_dt(struct ltc2983_data *st)
> {
> struct device *dev = &st->spi->dev;
> - struct fwnode_handle *child;
> - int ret = 0, chan = 0, channel_avail_mask = 0;
> + int ret, chan = 0, channel_avail_mask = 0;
>
> device_property_read_u32(dev, "adi,mux-delay-config-us", &st-
> >mux_delay_config);
>
> @@ -1368,38 +1339,35 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
> return -ENOMEM;
>
> st->iio_channels = st->num_channels;
> - device_for_each_child_node(dev, child) {
> + device_for_each_child_node_scoped(dev, child) {
> struct ltc2983_sensor sensor;
>
> ret = fwnode_property_read_u32(child, "reg", &sensor.chan);
> - if (ret) {
> - dev_err(dev, "reg property must given for child nodes\n");
> - goto put_child;
> - }
> + if (ret)
> + return dev_err_probe(dev, ret,
> + "reg property must given for child nodes\n");
>
> /* check if we have a valid channel */
> if (sensor.chan < LTC2983_MIN_CHANNELS_NR ||
> - sensor.chan > st->info->max_channels_nr) {
> - ret = -EINVAL;
> - dev_err(dev, "chan:%d must be from %u to %u\n",
> sensor.chan,
> - LTC2983_MIN_CHANNELS_NR, st->info-
> >max_channels_nr);
> - goto put_child;
> - } else if (channel_avail_mask & BIT(sensor.chan)) {
> - ret = -EINVAL;
> - dev_err(dev, "chan:%d already in use\n", sensor.chan);
> - goto put_child;
> - }
> + sensor.chan > st->info->max_channels_nr)
> + return dev_err_probe(dev, -EINVAL,
> + "chan:%d must be from %u to %u\n",
> + sensor.chan,
> + LTC2983_MIN_CHANNELS_NR,
> + st->info->max_channels_nr);
> +
> + if (channel_avail_mask & BIT(sensor.chan))
> + return dev_err_probe(dev, -EINVAL,
> + "chan:%d already in use\n",
> + sensor.chan);
>
> ret = fwnode_property_read_u32(child, "adi,sensor-type",
> &sensor.type);
> - if (ret) {
> - dev_err(dev,
> + if (ret)
> + return dev_err_probe(dev, ret,
> "adi,sensor-type property must given for child
> nodes\n");
> - goto put_child;
> - }
>
> dev_dbg(dev, "Create new sensor, type %u, chann %u",
> - sensor.type,
> - sensor.chan);
> + sensor.type, sensor.chan);
>
> if (sensor.type >= LTC2983_SENSOR_THERMOCOUPLE &&
> sensor.type <= LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) {
> @@ -1426,17 +1394,15 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
> sensor.type == LTC2983_SENSOR_ACTIVE_TEMP) {
> st->sensors[chan] = ltc2983_temp_new(child, st, &sensor);
> } else {
> - dev_err(dev, "Unknown sensor type %d\n", sensor.type);
> - ret = -EINVAL;
> - goto put_child;
> + return dev_err_probe(dev, -EINVAL,
> + "Unknown sensor type %d\n",
> + sensor.type);
> }
>
> - if (IS_ERR(st->sensors[chan])) {
> - dev_err(dev, "Failed to create sensor %ld",
> - PTR_ERR(st->sensors[chan]));
> - ret = PTR_ERR(st->sensors[chan]);
> - goto put_child;
> - }
> + if (IS_ERR(st->sensors[chan]))
> + return dev_err_probe(dev, PTR_ERR(st->sensors[chan]),
> + "Failed to create sensor\n");
> +
> /* set generic sensor parameters */
> st->sensors[chan]->chan = sensor.chan;
> st->sensors[chan]->type = sensor.type;
> @@ -1446,9 +1412,6 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
> }
>
> return 0;
> -put_child:
> - fwnode_handle_put(child);
> - return ret;
> }
>
> static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,
