Input: synaptics_i2c - switch to using __cancel_delayed_work()
authorDmitry Torokhov <dmitry.torokhov@gmail.com>
Wed, 16 Sep 2009 08:06:42 +0000 (01:06 -0700)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Fri, 18 Sep 2009 06:24:01 +0000 (23:24 -0700)
cancel_delayed_work() may spin and therefore should not be used in
interrupt contexts.

Acked-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
drivers/input/mouse/synaptics_i2c.c

index eac9fdde7ee9c13db9f5dc0c64aed2fcb82ee24b..7283c78044af3cd9a6a701bdb9f94684daf80e5f 100644 (file)
@@ -203,7 +203,7 @@ MODULE_PARM_DESC(no_filter, "No Filter. Default = 0 (off)");
  * and the irq configuration should be set to Falling Edge Trigger
  */
 /* Control IRQ / Polling option */
-static int polling_req;
+static bool polling_req;
 module_param(polling_req, bool, 0444);
 MODULE_PARM_DESC(polling_req, "Request Polling. Default = 0 (use irq)");
 
@@ -217,6 +217,7 @@ struct synaptics_i2c {
        struct i2c_client       *client;
        struct input_dev        *input;
        struct delayed_work     dwork;
+       spinlock_t              lock;
        int                     no_data_count;
        int                     no_decel_param;
        int                     reduce_report_param;
@@ -366,17 +367,28 @@ static bool synaptics_i2c_get_input(struct synaptics_i2c *touch)
        return xy_delta || gesture;
 }
 
-static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
+static void synaptics_i2c_reschedule_work(struct synaptics_i2c *touch,
+                                         unsigned long delay)
 {
-       struct synaptics_i2c *touch = dev_id;
+       unsigned long flags;
+
+       spin_lock_irqsave(&touch->lock, flags);
 
        /*
-        * We want to have the work run immediately but it might have
-        * already been scheduled with a delay, that's why we have to
-        * cancel it first.
+        * If work is already scheduled then subsequent schedules will not
+        * change the scheduled time that's why we have to cancel it first.
         */
-       cancel_delayed_work(&touch->dwork);
-       schedule_delayed_work(&touch->dwork, 0);
+       __cancel_delayed_work(&touch->dwork);
+       schedule_delayed_work(&touch->dwork, delay);
+
+       spin_unlock_irqrestore(&touch->lock, flags);
+}
+
+static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
+{
+       struct synaptics_i2c *touch = dev_id;
+
+       synaptics_i2c_reschedule_work(touch, 0);
 
        return IRQ_HANDLED;
 }
@@ -452,7 +464,7 @@ static void synaptics_i2c_work_handler(struct work_struct *work)
         * We poll the device once in THREAD_IRQ_SLEEP_SECS and
         * if error is detected, we try to reset and reconfigure the touchpad.
         */
-       schedule_delayed_work(&touch->dwork, delay);
+       synaptics_i2c_reschedule_work(touch, delay);
 }
 
 static int synaptics_i2c_open(struct input_dev *input)
@@ -465,8 +477,8 @@ static int synaptics_i2c_open(struct input_dev *input)
                return ret;
 
        if (polling_req)
-               schedule_delayed_work(&touch->dwork,
-                                      msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
+               synaptics_i2c_reschedule_work(touch,
+                               msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
 
        return 0;
 }
@@ -521,6 +533,7 @@ struct synaptics_i2c *synaptics_i2c_touch_create(struct i2c_client *client)
        touch->scan_rate_param = scan_rate;
        set_scan_rate(touch, scan_rate);
        INIT_DELAYED_WORK(&touch->dwork, synaptics_i2c_work_handler);
+       spin_lock_init(&touch->lock);
 
        return touch;
 }
@@ -535,14 +548,12 @@ static int __devinit synaptics_i2c_probe(struct i2c_client *client,
        if (!touch)
                return -ENOMEM;
 
-       i2c_set_clientdata(client, touch);
-
        ret = synaptics_i2c_reset_config(client);
        if (ret)
                goto err_mem_free;
 
        if (client->irq < 1)
-               polling_req = 1;
+               polling_req = true;
 
        touch->input = input_allocate_device();
        if (!touch->input) {
@@ -563,7 +574,7 @@ static int __devinit synaptics_i2c_probe(struct i2c_client *client,
                        dev_warn(&touch->client->dev,
                                  "IRQ request failed: %d, "
                                  "falling back to polling\n", ret);
-                       polling_req = 1;
+                       polling_req = true;
                        synaptics_i2c_reg_set(touch->client,
                                              INTERRUPT_EN_REG, 0);
                }
@@ -580,12 +591,14 @@ static int __devinit synaptics_i2c_probe(struct i2c_client *client,
                         "Input device register failed: %d\n", ret);
                goto err_input_free;
        }
+
+       i2c_set_clientdata(client, touch);
+
        return 0;
 
 err_input_free:
        input_free_device(touch->input);
 err_mem_free:
-       i2c_set_clientdata(client, NULL);
        kfree(touch);
 
        return ret;
@@ -596,7 +609,7 @@ static int __devexit synaptics_i2c_remove(struct i2c_client *client)
        struct synaptics_i2c *touch = i2c_get_clientdata(client);
 
        if (!polling_req)
-               free_irq(touch->client->irq, touch);
+               free_irq(client->irq, touch);
 
        input_unregister_device(touch->input);
        i2c_set_clientdata(client, NULL);
@@ -627,8 +640,8 @@ static int synaptics_i2c_resume(struct i2c_client *client)
        if (ret)
                return ret;
 
-       schedule_delayed_work(&touch->dwork,
-                              msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
+       synaptics_i2c_reschedule_work(touch,
+                               msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
 
        return 0;
 }