twl4030_charger: Make the driver atomic notifier safe

This queues work from the otg notification where the
i2c operations can be safely made. Needed for atomic otg
notifiers.

Signed-off-by: Heikki Krogerus <heikki.krogerus@nokia.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/power/twl4030_charger.c b/drivers/power/twl4030_charger.c
index ff1f42398a2..92c16e1677b 100644
--- a/drivers/power/twl4030_charger.c
+++ b/drivers/power/twl4030_charger.c
@@ -71,8 +71,11 @@ struct twl4030_bci {
         struct power_supply     usb;
         struct otg_transceiver  *transceiver;
         struct notifier_block   otg_nb;
+        struct work_struct      work;
         int                     irq_chg;
         int                     irq_bci;
+
+        unsigned long           event;
 };
 
 /*
@@ -258,14 +261,11 @@ static irqreturn_t twl4030_bci_interrupt(int irq, void *arg)
         return IRQ_HANDLED;
 }
 
-static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val,
-                               void *priv)
+static void twl4030_bci_usb_work(struct work_struct *data)
 {
-        struct twl4030_bci *bci = container_of(nb, struct twl4030_bci, otg_nb);
+        struct twl4030_bci *bci = container_of(data, struct twl4030_bci, work);
 
-        dev_dbg(bci->dev, "OTG notify %lu\n", val);
-
-        switch (val) {
+        switch (bci->event) {
         case USB_EVENT_VBUS:
         case USB_EVENT_CHARGER:
                 twl4030_charger_enable_usb(bci, true);
@@ -274,6 +274,17 @@ static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val,
                 twl4030_charger_enable_usb(bci, false);
                 break;
         }
+}
+
+static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val,
+                               void *priv)
+{
+        struct twl4030_bci *bci = container_of(nb, struct twl4030_bci, otg_nb);
+
+        dev_dbg(bci->dev, "OTG notify %lu\n", val);
+
+        bci->event = val;
+        schedule_work(&bci->work);
 
         return NOTIFY_OK;
 }
@@ -466,6 +477,8 @@ static int __init twl4030_bci_probe(struct platform_device *pdev)
                 goto fail_bci_irq;
         }
 
+        INIT_WORK(&bci->work, twl4030_bci_usb_work);
+
         bci->transceiver = otg_get_transceiver();
         if (bci->transceiver != NULL) {
                 bci->otg_nb.notifier_call = twl4030_bci_usb_ncb;