hwmon: (pmbus) Simplify memory allocation for labels and booleans

Since memory is now allocated with dev_ functions, we no longer need to keep
track of allocated memory. Memory allocation for booleans and labels can
therefore be simplified substantially by allocating it only as needed.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 149 insertions, 116 deletions

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 97eca0340dc0..0f51cd66ecfd 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -102,11 +102,14 @@ struct pmbus_boolean {
 
 struct pmbus_label {
         char name[PMBUS_NAME_SIZE];     /* sysfs label name */
-        struct sensor_device_attribute attribute;
+        struct device_attribute attribute;
         char label[PMBUS_NAME_SIZE];    /* label */
 };
+#define to_pmbus_label(_attr) \
+        container_of(_attr, struct pmbus_label, attribute)
 
 struct pmbus_data {
+        struct device *dev;
         struct device *hwmon_dev;
 
         u32 flags;              /* from platform data */
@@ -126,20 +129,6 @@ struct pmbus_data {
         int max_sensors;
         int num_sensors;
         struct pmbus_sensor *sensors;
-        /*
-         * Booleans are used for alarms.
-         * Values are determined from status registers.
-         */
-        int max_booleans;
-        int num_booleans;
-        struct pmbus_boolean *booleans;
-        /*
-         * Labels are used to map generic names (e.g., "in1")
-         * to PMBus specific names (e.g., "vin" or "vout1").
-         */
-        int max_labels;
-        int num_labels;
-        struct pmbus_label *labels;
 
         struct mutex update_lock;
         bool valid;
@@ -801,12 +790,26 @@ static ssize_t pmbus_set_sensor(struct device *dev,
 static ssize_t pmbus_show_label(struct device *dev,
                                 struct device_attribute *da, char *buf)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct pmbus_data *data = i2c_get_clientdata(client);
-        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+        struct pmbus_label *label = to_pmbus_label(da);
+
+        return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
+}
 
-        return snprintf(buf, PAGE_SIZE, "%s\n",
-                        data->labels[attr->index].label);
+static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
+                                const char *name,
+                                umode_t mode,
+                                ssize_t (*show)(struct device *dev,
+                                                struct device_attribute *attr,
+                                                char *buf),
+                                ssize_t (*store)(struct device *dev,
+                                                 struct device_attribute *attr,
+                                                 const char *buf, size_t count))
+{
+        sysfs_attr_init(&dev_attr->attr);
+        dev_attr->attr.name = name;
+        dev_attr->attr.mode = mode;
+        dev_attr->show = show;
+        dev_attr->store = store;
 }
 
 static void pmbus_attr_init(struct sensor_device_attribute *a,
@@ -820,25 +823,23 @@ static void pmbus_attr_init(struct sensor_device_attribute *a,
                                              const char *buf, size_t count),
                             int idx)
 {
-        sysfs_attr_init(&a->dev_attr.attr);
-        a->dev_attr.attr.name = name;
-        a->dev_attr.attr.mode = mode;
-        a->dev_attr.show = show;
-        a->dev_attr.store = store;
+        pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
         a->index = idx;
 }
 
-static void pmbus_add_boolean(struct pmbus_data *data,
-                              const char *name, const char *type, int seq,
-                              int idx)
+static int pmbus_add_boolean(struct pmbus_data *data,
+                             const char *name, const char *type, int seq,
+                             int idx)
 {
         struct pmbus_boolean *boolean;
         struct sensor_device_attribute *a;
 
-        BUG_ON(data->num_booleans >= data->max_booleans ||
-               data->num_attributes >= data->max_attributes);
+        BUG_ON(data->num_attributes >= data->max_attributes);
+
+        boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
+        if (!boolean)
+                return -ENOMEM;
 
-        boolean = &data->booleans[data->num_booleans];
         a = &boolean->attribute;
 
         snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
@@ -846,22 +847,23 @@ static void pmbus_add_boolean(struct pmbus_data *data,
         pmbus_attr_init(a, boolean->name, S_IRUGO, pmbus_show_boolean, NULL,
                         idx);
         data->attributes[data->num_attributes++] = &a->dev_attr.attr;
-        data->num_booleans++;
+
+        return 0;
 }
 
-static void pmbus_add_boolean_reg(struct pmbus_data *data,
-                                  const char *name, const char *type,
-                                  int seq, int reg, int bit)
+static int pmbus_add_boolean_reg(struct pmbus_data *data,
+                                 const char *name, const char *type,
+                                 int seq, int reg, int bit)
 {
-        pmbus_add_boolean(data, name, type, seq, (reg << 8) | bit);
+        return pmbus_add_boolean(data, name, type, seq, (reg << 8) | bit);
 }
 
-static void pmbus_add_boolean_cmp(struct pmbus_data *data,
-                                  const char *name, const char *type,
-                                  int seq, int i1, int i2, int reg, int mask)
+static int pmbus_add_boolean_cmp(struct pmbus_data *data,
+                                 const char *name, const char *type,
+                                 int seq, int i1, int i2, int reg, int mask)
 {
-        pmbus_add_boolean(data, name, type, seq,
-                          (i1 << 24) | (i2 << 16) | (reg << 8) | mask);
+        return pmbus_add_boolean(data, name, type, seq,
+                                 (i1 << 24) | (i2 << 16) | (reg << 8) | mask);
 }
 
 static void pmbus_add_sensor(struct pmbus_data *data,
@@ -892,17 +894,19 @@ static void pmbus_add_sensor(struct pmbus_data *data,
         data->num_sensors++;
 }
 
-static void pmbus_add_label(struct pmbus_data *data,
-                            const char *name, int seq,
-                            const char *lstring, int index)
+static int pmbus_add_label(struct pmbus_data *data,
+                           const char *name, int seq,
+                           const char *lstring, int index)
 {
         struct pmbus_label *label;
-        struct sensor_device_attribute *a;
+        struct device_attribute *a;
 
-        BUG_ON(data->num_labels >= data->max_labels ||
-               data->num_attributes >= data->max_attributes);
+        BUG_ON(data->num_attributes >= data->max_attributes);
+
+        label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
+        if (!label)
+                return -ENOMEM;
 
-        label = &data->labels[data->num_labels];
         a = &label->attribute;
 
         snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
@@ -912,10 +916,9 @@ static void pmbus_add_label(struct pmbus_data *data,
                 snprintf(label->label, sizeof(label->label), "%s%d", lstring,
                          index);
 
-        pmbus_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL,
-                        data->num_labels);
-        data->attributes[data->num_attributes++] = &a->dev_attr.attr;
-        data->num_labels++;
+        pmbus_dev_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL);
+        data->attributes[data->num_attributes++] = &a->attr;
+        return 0;
 }
 
 /*
@@ -970,8 +973,6 @@ static void pmbus_find_max_attr(struct i2c_client *client,
                 }
         }
         data->max_sensors = max_sensors;
-        data->max_booleans = max_booleans;
-        data->max_labels = max_labels;
         data->max_attributes = max_sensors + max_booleans + max_labels;
 }
 
@@ -1015,18 +1016,21 @@ struct pmbus_sensor_attr {
 /*
  * Add a set of limit attributes and, if supported, the associated
  * alarm attributes.
+ * returns 0 if no alarm register found, 1 if an alarm register was found,
+ * < 0 on errors.
  */
-static bool pmbus_add_limit_attrs(struct i2c_client *client,
-                                  struct pmbus_data *data,
-                                  const struct pmbus_driver_info *info,
-                                  const char *name, int index, int page,
-                                  int cbase,
-                                  const struct pmbus_sensor_attr *attr)
+static int pmbus_add_limit_attrs(struct i2c_client *client,
+                                 struct pmbus_data *data,
+                                 const struct pmbus_driver_info *info,
+                                 const char *name, int index, int page,
+                                 int cbase,
+                                 const struct pmbus_sensor_attr *attr)
 {
         const struct pmbus_limit_attr *l = attr->limit;
         int nlimit = attr->nlimit;
-        bool have_alarm = false;
+        int have_alarm = 0;
         int i, cindex;
+        int ret;
 
         for (i = 0; i < nlimit; i++) {
                 if (pmbus_check_word_register(client, page, l->reg)) {
@@ -1037,17 +1041,21 @@ static bool pmbus_add_limit_attrs(struct i2c_client *client,
                                          false);
                         if (l->sbit && (info->func[page] & attr->sfunc)) {
                                 if (attr->compare) {
-                                        pmbus_add_boolean_cmp(data, name,
+                                        ret = pmbus_add_boolean_cmp(data, name,
                                                 l->alarm, index,
                                                 l->low ? cindex : cbase,
                                                 l->low ? cbase : cindex,
                                                 attr->sbase + page, l->sbit);
+                                        if (ret)
+                                                return ret;
                                 } else {
-                                        pmbus_add_boolean_reg(data, name,
+                                        ret = pmbus_add_boolean_reg(data, name,
                                                 l->alarm, index,
                                                 attr->sbase + page, l->sbit);
+                                        if (ret)
+                                                return ret;
                                 }
-                                have_alarm = true;
+                                have_alarm = 1;
                         }
                 }
                 l++;
@@ -1055,45 +1063,56 @@ static bool pmbus_add_limit_attrs(struct i2c_client *client,
         return have_alarm;
 }
 
-static void pmbus_add_sensor_attrs_one(struct i2c_client *client,
-                                       struct pmbus_data *data,
-                                       const struct pmbus_driver_info *info,
-                                       const char *name,
-                                       int index, int page,
-                                       const struct pmbus_sensor_attr *attr)
+static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
+                                      struct pmbus_data *data,
+                                      const struct pmbus_driver_info *info,
+                                      const char *name,
+                                      int index, int page,
+                                      const struct pmbus_sensor_attr *attr)
 {
-        bool have_alarm;
         int cbase = data->num_sensors;
+        int ret;
 
-        if (attr->label)
-                pmbus_add_label(data, name, index, attr->label,
-                                attr->paged ? page + 1 : 0);
+        if (attr->label) {
+                ret = pmbus_add_label(data, name, index, attr->label,
+                                      attr->paged ? page + 1 : 0);
+                if (ret)
+                        return ret;
+        }
         pmbus_add_sensor(data, name, "input", index, page, attr->reg,
                          attr->class, true, true);
         if (attr->sfunc) {
-                have_alarm = pmbus_add_limit_attrs(client, data, info, name,
-                                                   index, page, cbase, attr);
+                ret = pmbus_add_limit_attrs(client, data, info, name,
+                                            index, page, cbase, attr);
+                if (ret < 0)
+                        return ret;
                 /*
                  * Add generic alarm attribute only if there are no individual
                  * alarm attributes, if there is a global alarm bit, and if
                  * the generic status register for this page is accessible.
                  */
-                if (!have_alarm && attr->gbit &&
-                    pmbus_check_byte_register(client, page, PMBUS_STATUS_BYTE))
-                        pmbus_add_boolean_reg(data, name, "alarm", index,
-                                              PB_STATUS_BASE + page,
-                                              attr->gbit);
+                if (!ret && attr->gbit &&
+                    pmbus_check_byte_register(client, page,
+                                              PMBUS_STATUS_BYTE)) {
+                        ret = pmbus_add_boolean_reg(data, name, "alarm", index,
+                                                    PB_STATUS_BASE + page,
+                                                    attr->gbit);
+                        if (ret)
+                                return ret;
+                }
         }
+        return 0;
 }
 
-static void pmbus_add_sensor_attrs(struct i2c_client *client,
-                                   struct pmbus_data *data,
-                                   const char *name,
-                                   const struct pmbus_sensor_attr *attrs,
-                                   int nattrs)
+static int pmbus_add_sensor_attrs(struct i2c_client *client,
+                                  struct pmbus_data *data,
+                                  const char *name,
+                                  const struct pmbus_sensor_attr *attrs,
+                                  int nattrs)
 {
         const struct pmbus_driver_info *info = data->info;
         int index, i;
+        int ret;
 
         index = 1;
         for (i = 0; i < nattrs; i++) {
@@ -1103,12 +1122,16 @@ static void pmbus_add_sensor_attrs(struct i2c_client *client,
                 for (page = 0; page < pages; page++) {
                         if (!(info->func[page] & attrs->func))
                                 continue;
-                        pmbus_add_sensor_attrs_one(client, data, info, name,
-                                                   index, page, attrs);
+                        ret = pmbus_add_sensor_attrs_one(client, data, info,
+                                                         name, index, page,
+                                                         attrs);
+                        if (ret)
+                                return ret;
                         index++;
                 }
                 attrs++;
         }
+        return 0;
 }
 
 static const struct pmbus_limit_attr vin_limit_attrs[] = {
@@ -1563,12 +1586,13 @@ static const u32 pmbus_fan_status_flags[] = {
 };
 
 /* Fans */
-static void pmbus_add_fan_attributes(struct i2c_client *client,
-                                     struct pmbus_data *data)
+static int pmbus_add_fan_attributes(struct i2c_client *client,
+                                    struct pmbus_data *data)
 {
         const struct pmbus_driver_info *info = data->info;
         int index = 1;
         int page;
+        int ret;
 
         for (page = 0; page < info->pages; page++) {
                 int f;
@@ -1611,39 +1635,55 @@ static void pmbus_add_fan_attributes(struct i2c_client *client,
                                         base = PB_STATUS_FAN34_BASE + page;
                                 else
                                         base = PB_STATUS_FAN_BASE + page;
-                                pmbus_add_boolean_reg(data, "fan", "alarm",
-                                        index, base,
+                                ret = pmbus_add_boolean_reg(data, "fan",
+                                        "alarm", index, base,
                                         PB_FAN_FAN1_WARNING >> (f & 1));
-                                pmbus_add_boolean_reg(data, "fan", "fault",
-                                        index, base,
+                                if (ret)
+                                        return ret;
+                                ret = pmbus_add_boolean_reg(data, "fan",
+                                        "fault", index, base,
                                         PB_FAN_FAN1_FAULT >> (f & 1));
+                                if (ret)
+                                        return ret;
                         }
                         index++;
                 }
         }
+        return 0;
 }
 
-static void pmbus_find_attributes(struct i2c_client *client,
-                                  struct pmbus_data *data)
+static int pmbus_find_attributes(struct i2c_client *client,
+                                 struct pmbus_data *data)
 {
+        int ret;
+
         /* Voltage sensors */
-        pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
-                               ARRAY_SIZE(voltage_attributes));
+        ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
+                                     ARRAY_SIZE(voltage_attributes));
+        if (ret)
+                return ret;
 
         /* Current sensors */
-        pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
-                               ARRAY_SIZE(current_attributes));
+        ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
+                                     ARRAY_SIZE(current_attributes));
+        if (ret)
+                return ret;
 
         /* Power sensors */
-        pmbus_add_sensor_attrs(client, data, "power", power_attributes,
-                               ARRAY_SIZE(power_attributes));
+        ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
+                                     ARRAY_SIZE(power_attributes));
+        if (ret)
+                return ret;
 
         /* Temperature sensors */
-        pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
-                               ARRAY_SIZE(temp_attributes));
+        ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
+                                     ARRAY_SIZE(temp_attributes));
+        if (ret)
+                return ret;
 
         /* Fans */
-        pmbus_add_fan_attributes(client, data);
+        ret = pmbus_add_fan_attributes(client, data);
+        return ret;
 }
 
 /*
@@ -1710,6 +1750,7 @@ int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
 
         i2c_set_clientdata(client, data);
         mutex_init(&data->update_lock);
+        data->dev = dev;
 
         /* Bail out if PMBus status register does not exist. */
         if (i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE) < 0) {
@@ -1747,22 +1788,14 @@ int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
         if (!data->sensors)
                 return -ENOMEM;
 
-        data->booleans = devm_kzalloc(dev, sizeof(struct pmbus_boolean)
-                                      * data->max_booleans, GFP_KERNEL);
-        if (!data->booleans)
-                return -ENOMEM;
-
-        data->labels = devm_kzalloc(dev, sizeof(struct pmbus_label)
-                                    * data->max_labels, GFP_KERNEL);
-        if (!data->labels)
-                return -ENOMEM;
-
         data->attributes = devm_kzalloc(dev, sizeof(struct attribute *)
                                         * data->max_attributes, GFP_KERNEL);
         if (!data->attributes)
                 return -ENOMEM;
 
-        pmbus_find_attributes(client, data);
+        ret = pmbus_find_attributes(client, data);
+        if (ret)
+                return ret;
 
         /*
          * If there are no attributes, something is wrong.