Input: synaptics_i2c - switch to using __cancel_delayed_work()

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>

1 files changed, 32 insertions, 19 deletions

diff --git a/drivers/input/mouse/synaptics_i2c.c b/drivers/input/mouse/synaptics_i2c.c
index eac9fdde7ee9..7283c78044af 100644
--- a/drivers/input/mouse/synaptics_i2c.c
+++ b/drivers/input/mouse/synaptics_i2c.c
@@ -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;
 }