power: supply: sysfs: parse string as enum when writing property

This fixes the TODO to parse strings and convert them to enum values
when writing to a power_supply class property sysfs attribute.

There is at least one driver that has a writable enum property that
previously could only be written as an integer, so a fallback to writing
enums as integers instead of strings is provided so we don't break existing
userspace programs.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

diff --git a/drivers/power/supply/power_supply_sysfs.c b/drivers/power/supply/power_supply_sysfs.c
index 07b484f995c1233d284a2537410d5575b1fa1604..b32c1418377372f5508fae83be4a40b7bb109551 100644 (file)
--- a/drivers/power/supply/power_supply_sysfs.c
+++ b/drivers/power/supply/power_supply_sysfs.c
@@ -40,35 +40,42 @@
 
 static struct device_attribute power_supply_attrs[];
 
+static const char * const power_supply_type_text[] = {
+       "Unknown", "Battery", "UPS", "Mains", "USB",
+       "USB_DCP", "USB_CDP", "USB_ACA", "USB_C",
+       "USB_PD", "USB_PD_DRP", "BrickID"
+};
+
+static const char * const power_supply_status_text[] = {
+       "Unknown", "Charging", "Discharging", "Not charging", "Full"
+};
+
+static const char * const power_supply_charge_type_text[] = {
+       "Unknown", "N/A", "Trickle", "Fast"
+};
+
+static const char * const power_supply_health_text[] = {
+       "Unknown", "Good", "Overheat", "Dead", "Over voltage",
+       "Unspecified failure", "Cold", "Watchdog timer expire",
+       "Safety timer expire"
+};
+
+static const char * const power_supply_technology_text[] = {
+       "Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", "NiCd",
+       "LiMn"
+};
+
+static const char * const power_supply_capacity_level_text[] = {
+       "Unknown", "Critical", "Low", "Normal", "High", "Full"
+};
+
+static const char * const power_supply_scope_text[] = {
+       "Unknown", "System", "Device"
+};
+
 static ssize_t power_supply_show_property(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf) {
-       static char *type_text[] = {
-               "Unknown", "Battery", "UPS", "Mains", "USB",
-               "USB_DCP", "USB_CDP", "USB_ACA", "USB_C",
-               "USB_PD", "USB_PD_DRP", "BrickID"
-       };
-       static char *status_text[] = {
-               "Unknown", "Charging", "Discharging", "Not charging", "Full"
-       };
-       static char *charge_type[] = {
-               "Unknown", "N/A", "Trickle", "Fast"
-       };
-       static char *health_text[] = {
-               "Unknown", "Good", "Overheat", "Dead", "Over voltage",
-               "Unspecified failure", "Cold", "Watchdog timer expire",
-               "Safety timer expire"
-       };
-       static char *technology_text[] = {
-               "Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", "NiCd",
-               "LiMn"
-       };
-       static char *capacity_level_text[] = {
-               "Unknown", "Critical", "Low", "Normal", "High", "Full"
-       };
-       static char *scope_text[] = {
-               "Unknown", "System", "Device"
-       };
        ssize_t ret = 0;
        struct power_supply *psy = dev_get_drvdata(dev);
        const ptrdiff_t off = attr - power_supply_attrs;
@@ -91,19 +98,26 @@ static ssize_t power_supply_show_property(struct device *dev,
        }
 
        if (off == POWER_SUPPLY_PROP_STATUS)
-               return sprintf(buf, "%s\n", status_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_status_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_CHARGE_TYPE)
-               return sprintf(buf, "%s\n", charge_type[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_charge_type_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_HEALTH)
-               return sprintf(buf, "%s\n", health_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_health_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_TECHNOLOGY)
-               return sprintf(buf, "%s\n", technology_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_technology_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_CAPACITY_LEVEL)
-               return sprintf(buf, "%s\n", capacity_level_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_capacity_level_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_TYPE)
-               return sprintf(buf, "%s\n", type_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_type_text[value.intval]);
        else if (off == POWER_SUPPLY_PROP_SCOPE)
-               return sprintf(buf, "%s\n", scope_text[value.intval]);
+               return sprintf(buf, "%s\n",
+                              power_supply_scope_text[value.intval]);
        else if (off >= POWER_SUPPLY_PROP_MODEL_NAME)
                return sprintf(buf, "%s\n", value.strval);
 
@@ -117,14 +131,46 @@ static ssize_t power_supply_store_property(struct device *dev,
        struct power_supply *psy = dev_get_drvdata(dev);
        const ptrdiff_t off = attr - power_supply_attrs;
        union power_supply_propval value;
-       long long_val;
 
-       /* TODO: support other types than int */
-       ret = kstrtol(buf, 10, &long_val);
-       if (ret < 0)
-               return ret;
+       /* maybe it is a enum property? */
+       switch (off) {
+       case POWER_SUPPLY_PROP_STATUS:
+               ret = sysfs_match_string(power_supply_status_text, buf);
+               break;
+       case POWER_SUPPLY_PROP_CHARGE_TYPE:
+               ret = sysfs_match_string(power_supply_charge_type_text, buf);
+               break;
+       case POWER_SUPPLY_PROP_HEALTH:
+               ret = sysfs_match_string(power_supply_health_text, buf);
+               break;
+       case POWER_SUPPLY_PROP_TECHNOLOGY:
+               ret = sysfs_match_string(power_supply_technology_text, buf);
+               break;
+       case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+               ret = sysfs_match_string(power_supply_capacity_level_text, buf);
+               break;
+       case POWER_SUPPLY_PROP_SCOPE:
+               ret = sysfs_match_string(power_supply_scope_text, buf);
+               break;
+       default:
+               ret = -EINVAL;
+       }
+
+       /*
+        * If no match was found, then check to see if it is an integer.
+        * Integer values are valid for enums in addition to the text value.
+        */
+       if (ret < 0) {
+               long long_val;
+
+               ret = kstrtol(buf, 10, &long_val);
+               if (ret < 0)
+                       return ret;
+
+               ret = long_val;
+       }
 
-       value.intval = long_val;
+       value.intval = ret;
 
        ret = power_supply_set_property(psy, off, &value);
        if (ret < 0)