2 files changed, 80 insertions, 5 deletions

diff --git a/drivers/power/pcf50633-charger.c b/drivers/power/pcf50633-charger.c
index 48e92c020f4b..21b6e64e7805 100644
--- a/drivers/power/pcf50633-charger.c
+++ b/drivers/power/pcf50633-charger.c
@@ -48,16 +48,21 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
         u8 bits;
         int charging_start = 1;
         u8 mbcs2, chgmod;
+        unsigned int mbcc5;
 
-        if (ma >= 1000)
+        if (ma >= 1000) {
                 bits = PCF50633_MBCC7_USB_1000mA;
-        else if (ma >= 500)
+                ma = 1000;
+        } else if (ma >= 500) {
                 bits = PCF50633_MBCC7_USB_500mA;
-        else if (ma >= 100)
+                ma = 500;
+        } else if (ma >= 100) {
                 bits = PCF50633_MBCC7_USB_100mA;
-        else {
+                ma = 100;
+        } else {
                 bits = PCF50633_MBCC7_USB_SUSPEND;
                 charging_start = 0;
+                ma = 0;
         }
 
         ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7,
@@ -67,7 +72,24 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
         else
                 dev_info(pcf->dev, "usb curlim to %d mA\n", ma);
 
-        /* Manual charging start */
+        /*
+         * We limit the charging current to be the USB current limit.
+         * The reason is that on pcf50633, when it enters PMU Standby mode,
+         * which it does when the device goes "off", the USB current limit
+         * reverts to the variant default.  In at least one common case, that
+         * default is 500mA.  By setting the charging current to be the same
+         * as the USB limit we set here before PMU standby, we enforce it only
+         * using the correct amount of current even when the USB current limit
+         * gets reset to the wrong thing
+         */
+
+        if (mbc->pcf->pdata->charger_reference_current_ma) {
+                mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
+                if (mbcc5 > 255)
+                        mbcc5 = 255;
+                pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
+        }
+
         mbcs2 = pcf50633_reg_read(pcf, PCF50633_REG_MBCS2);
         chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
 
@@ -157,9 +179,55 @@ static ssize_t set_usblim(struct device *dev,
 
 static DEVICE_ATTR(usb_curlim, S_IRUGO | S_IWUSR, show_usblim, set_usblim);
 
+static ssize_t
+show_chglim(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
+        u8 mbcc5 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC5);
+        unsigned int ma;
+
+        if (!mbc->pcf->pdata->charger_reference_current_ma)
+                return -ENODEV;
+
+        ma = (mbc->pcf->pdata->charger_reference_current_ma *  mbcc5) >> 8;
+
+        return sprintf(buf, "%u\n", ma);
+}
+
+static ssize_t set_chglim(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
+        unsigned long ma;
+        unsigned int mbcc5;
+        int ret;
+
+        if (!mbc->pcf->pdata->charger_reference_current_ma)
+                return -ENODEV;
+
+        ret = strict_strtoul(buf, 10, &ma);
+        if (ret)
+                return -EINVAL;
+
+        mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
+        if (mbcc5 > 255)
+                mbcc5 = 255;
+        pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
+
+        return count;
+}
+
+/*
+ * This attribute allows to change MBC charging limit on the fly
+ * independently of usb current limit. It also gets set automatically every
+ * time usb current limit is changed.
+ */
+static DEVICE_ATTR(chg_curlim, S_IRUGO | S_IWUSR, show_chglim, set_chglim);
+
 static struct attribute *pcf50633_mbc_sysfs_entries[] = {
         &dev_attr_chgmode.attr,
         &dev_attr_usb_curlim.attr,
+        &dev_attr_chg_curlim.attr,
         NULL,
 };
 
diff --git a/include/linux/mfd/pcf50633/core.h b/include/linux/mfd/pcf50633/core.h
index 9aba7b779fbc..09af8fdfbb5d 100644
--- a/include/linux/mfd/pcf50633/core.h
+++ b/include/linux/mfd/pcf50633/core.h
@@ -31,6 +31,13 @@ struct pcf50633_platform_data {
 
         int charging_restart_interval;
 
+        /*
+         * Should be set accordingly to the reference resistor used, see
+         * I_{ch(ref)} charger reference current in the pcf50633 User
+         * Manual.
+         */
+        int charger_reference_current_ma;
+
         /* Callbacks */
         void (*probe_done)(struct pcf50633 *);
         void (*mbc_event_callback)(struct pcf50633 *, int);