Merge branches 'for-4.4/upstream-fixes', 'for-4.5/async-suspend', 'for-4.5/container...

[cascardo/linux.git] / drivers / hid / i2c-hid / i2c-hid.c

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 55d8f9d..b921693 100644 (file)
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -151,6 +151,7 @@ struct i2c_hid {
        struct i2c_hid_platform_data pdata;
 
        bool                    irq_wake_enabled;
+       struct mutex            reset_lock;
 };
 
 static int __i2c_hid_command(struct i2c_client *client,
@@ -356,9 +357,16 @@ static int i2c_hid_hwreset(struct i2c_client *client)
 
        i2c_hid_dbg(ihid, "%s\n", __func__);
 
+       /*
+        * This prevents sending feature reports while the device is
+        * being reset. Otherwise we may lose the reset complete
+        * interrupt.
+        */
+       mutex_lock(&ihid->reset_lock);
+
        ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
        if (ret)
-               return ret;
+               goto out_unlock;
 
        i2c_hid_dbg(ihid, "resetting...\n");
 
@@ -366,10 +374,11 @@ static int i2c_hid_hwreset(struct i2c_client *client)
        if (ret) {
                dev_err(&client->dev, "failed to reset device.\n");
                i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
-               return ret;
        }
 
-       return 0;
+out_unlock:
+       mutex_unlock(&ihid->reset_lock);
+       return ret;
 }
 
 static void i2c_hid_get_input(struct i2c_hid *ihid)
@@ -587,12 +596,15 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
                size_t count, unsigned char report_type, bool use_data)
 {
        struct i2c_client *client = hid->driver_data;
+       struct i2c_hid *ihid = i2c_get_clientdata(client);
        int report_id = buf[0];
        int ret;
 
        if (report_type == HID_INPUT_REPORT)
                return -EINVAL;
 
+       mutex_lock(&ihid->reset_lock);
+
        if (report_id) {
                buf++;
                count--;
@@ -605,6 +617,8 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
        if (report_id && ret >= 0)
                ret++; /* add report_id to the number of transfered bytes */
 
+       mutex_unlock(&ihid->reset_lock);
+
        return ret;
 }
 
@@ -990,6 +1004,7 @@ static int i2c_hid_probe(struct i2c_client *client,
        ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
 
        init_waitqueue_head(&ihid->wait);
+       mutex_init(&ihid->reset_lock);
 
        /* we need to allocate the command buffer without knowing the maximum
         * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the