usb: phy: twl4030-usb: Use mutex instead of spinlock for protecting the data

We're using threaded irq on a I2C bus and we're sleeping in
twl4030_usb_irq() as it calls twl4030_usb_linkstat() which
calls the i2c functions. If we ever need to lock for longer
I2C transaction sequences a mutex will allow us to do that
easily.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c
index 24ff3c6..1e0e2d1 100644 (file)
--- a/drivers/phy/phy-twl4030-usb.c
+++ b/drivers/phy/phy-twl4030-usb.c
@@ -28,7 +28,6 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
-#include <linux/spinlock.h>
 #include <linux/workqueue.h>
 #include <linux/io.h>
 #include <linux/delay.h>
@@ -155,7 +154,7 @@ struct twl4030_usb {
        struct regulator        *usb3v1;
 
        /* for vbus reporting with irqs disabled */
-       spinlock_t              lock;
+       struct mutex            lock;
 
        /* pin configuration */
        enum twl4030_usb_mode   usb_mode;
@@ -516,13 +515,12 @@ static ssize_t twl4030_usb_vbus_show(struct device *dev,
                struct device_attribute *attr, char *buf)
 {
        struct twl4030_usb *twl = dev_get_drvdata(dev);
-       unsigned long flags;
        int ret = -EINVAL;
 
-       spin_lock_irqsave(&twl->lock, flags);
+       mutex_lock(&twl->lock);
        ret = sprintf(buf, "%s\n",
                        twl->vbus_supplied ? "on" : "off");
-       spin_unlock_irqrestore(&twl->lock, flags);
+       mutex_unlock(&twl->lock);
 
        return ret;
 }
@@ -536,12 +534,12 @@ static irqreturn_t twl4030_usb_irq(int irq, void *_twl)
 
        status = twl4030_usb_linkstat(twl);
 
-       spin_lock_irq(&twl->lock);
+       mutex_lock(&twl->lock);
        if (status >= 0 && status != twl->linkstat) {
                twl->linkstat = status;
                status_changed = true;
        }
-       spin_unlock_irq(&twl->lock);
+       mutex_unlock(&twl->lock);
 
        if (status_changed) {
                /* FIXME add a set_power() method so that B-devices can
@@ -695,8 +693,8 @@ static int twl4030_usb_probe(struct platform_device *pdev)
        if (IS_ERR(phy_provider))
                return PTR_ERR(phy_provider);
 
-       /* init spinlock for workqueue */
-       spin_lock_init(&twl->lock);
+       /* init mutex for workqueue */
+       mutex_init(&twl->lock);
 
        INIT_DELAYED_WORK(&twl->id_workaround_work, twl4030_id_workaround_work);