power: supply: smb347-charger: Replace mutex with IRQ disable/enable

Let's simply disable/enable IRQ rather than use a mutex that protects from
racing with the interrupt handler. The result of this patch is that it's a
bit easier now to follow the driver's code.

Tested-by: David Heidelberg <david@ixit.cz>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

diff --git a/drivers/power/supply/smb347-charger.c b/drivers/power/supply/smb347-charger.c
index 335b6ee..ec68ab2 100644 (file)
--- a/drivers/power/supply/smb347-charger.c
+++ b/drivers/power/supply/smb347-charger.c
@@ -16,7 +16,6 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
-#include <linux/mutex.h>
 #include <linux/power_supply.h>
 #include <linux/power/smb347-charger.h>
 #include <linux/regmap.h>
@@ -122,7 +121,6 @@
 
 /**
  * struct smb347_charger - smb347 charger instance
- * @lock: protects concurrent access to online variables
  * @dev: pointer to device
  * @regmap: pointer to driver regmap
  * @mains: power_supply instance for AC/DC power
@@ -134,7 +132,6 @@
  * @pdata: pointer to platform data
  */
 struct smb347_charger {
-       struct mutex            lock;
        struct device           *dev;
        struct regmap           *regmap;
        struct power_supply     *mains;
@@ -243,11 +240,9 @@ static int smb347_update_ps_status(struct smb347_charger *smb)
        if (smb->pdata->use_usb)
                usb = !(val & IRQSTAT_E_USBIN_UV_STAT);
 
-       mutex_lock(&smb->lock);
        ret = smb->mains_online != dc || smb->usb_online != usb;
        smb->mains_online = dc;
        smb->usb_online = usb;
-       mutex_unlock(&smb->lock);
 
        return ret;
 }
@@ -263,13 +258,7 @@ static int smb347_update_ps_status(struct smb347_charger *smb)
  */
 static bool smb347_is_ps_online(struct smb347_charger *smb)
 {
-       bool ret;
-
-       mutex_lock(&smb->lock);
-       ret = smb->usb_online || smb->mains_online;
-       mutex_unlock(&smb->lock);
-
-       return ret;
+       return smb->usb_online || smb->mains_online;
 }
 
 /**
@@ -303,14 +292,13 @@ static int smb347_charging_set(struct smb347_charger *smb, bool enable)
                return 0;
        }
 
-       mutex_lock(&smb->lock);
        if (smb->charging_enabled != enable) {
                ret = regmap_update_bits(smb->regmap, CMD_A, CMD_A_CHG_ENABLED,
                                         enable ? CMD_A_CHG_ENABLED : 0);
                if (!ret)
                        smb->charging_enabled = enable;
        }
-       mutex_unlock(&smb->lock);
+
        return ret;
 }
 
@@ -995,9 +983,9 @@ static int smb347_get_charging_status(struct smb347_charger *smb,
        return status;
 }
 
-static int smb347_get_property(struct power_supply *psy,
-                              enum power_supply_property prop,
-                              union power_supply_propval *val)
+static int smb347_get_property_locked(struct power_supply *psy,
+                                     enum power_supply_property prop,
+                                     union power_supply_propval *val)
 {
        struct smb347_charger *smb = power_supply_get_drvdata(psy);
        int ret;
@@ -1064,6 +1052,21 @@ static int smb347_get_property(struct power_supply *psy,
        return 0;
 }
 
+static int smb347_get_property(struct power_supply *psy,
+                              enum power_supply_property prop,
+                              union power_supply_propval *val)
+{
+       struct smb347_charger *smb = power_supply_get_drvdata(psy);
+       struct i2c_client *client = to_i2c_client(smb->dev);
+       int ret;
+
+       disable_irq(client->irq);
+       ret = smb347_get_property_locked(psy, prop, val);
+       enable_irq(client->irq);
+
+       return ret;
+}
+
 static enum power_supply_property smb347_properties[] = {
        POWER_SUPPLY_PROP_STATUS,
        POWER_SUPPLY_PROP_CHARGE_TYPE,
@@ -1273,7 +1276,6 @@ static int smb347_probe(struct i2c_client *client,
 
        i2c_set_clientdata(client, smb);
 
-       mutex_init(&smb->lock);
        smb->dev = &client->dev;
        smb->id = id->driver_data;