HID: multitouch: devm conversion

HID special drivers can use safely the devres API.
Use it to remove 25 lines of code and to clean up a little the error paths.

Besides the basic kzalloc -> devm_kzalloc conversions, I changed the
place of the allocation of the new name. Doing this right in
mt_input_configured() removes the kstrdup call which was not very helpful
and the new way is simpler to understand (and to debug).

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index cb0e361..0fe00e2 100644 (file)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -261,17 +261,6 @@ static struct mt_class mt_classes[] = {
        { }
 };
 
-static void mt_free_input_name(struct hid_input *hi)
-{
-       struct hid_device *hdev = hi->report->device;
-       const char *name = hi->input->name;
-
-       if (name != hdev->name) {
-               hi->input->name = hdev->name;
-               kfree(name);
-       }
-}
-
 static ssize_t mt_show_quirks(struct device *dev,
                           struct device_attribute *attr,
                           char *buf)
@@ -415,13 +404,6 @@ static void mt_pen_report(struct hid_device *hid, struct hid_report *report)
 static void mt_pen_input_configured(struct hid_device *hdev,
                                        struct hid_input *hi)
 {
-       char *name = kzalloc(strlen(hi->input->name) + 5, GFP_KERNEL);
-       if (name) {
-               sprintf(name, "%s Pen", hi->input->name);
-               mt_free_input_name(hi);
-               hi->input->name = name;
-       }
-
        /* force BTN_STYLUS to allow tablet matching in udev */
        __set_bit(BTN_STYLUS, hi->input->keybit);
 }
@@ -928,16 +910,26 @@ static void mt_post_parse(struct mt_device *td)
 static void mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 {
        struct mt_device *td = hid_get_drvdata(hdev);
-       char *name = kstrdup(hdev->name, GFP_KERNEL);
-
-       if (name)
-               hi->input->name = name;
+       char *name;
+       const char *suffix = NULL;
 
        if (hi->report->id == td->mt_report_id)
                mt_touch_input_configured(hdev, hi);
 
-       if (hi->report->id == td->pen_report_id)
+       if (hi->report->field[0]->physical == HID_DG_STYLUS) {
+               suffix = "Pen";
                mt_pen_input_configured(hdev, hi);
+       }
+
+       if (suffix) {
+               name = devm_kzalloc(&hi->input->dev,
+                                   strlen(hdev->name) + strlen(suffix) + 2,
+                                   GFP_KERNEL);
+               if (name) {
+                       sprintf(name, "%s %s", hdev->name, suffix);
+                       hi->input->name = name;
+               }
+       }
 }
 
 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
@@ -945,7 +937,6 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
        int ret, i;
        struct mt_device *td;
        struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */
-       struct hid_input *hi;
 
        for (i = 0; mt_classes[i].name ; i++) {
                if (id->driver_data == mt_classes[i].name) {
@@ -967,7 +958,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
        hdev->quirks |= HID_QUIRK_MULTI_INPUT;
        hdev->quirks |= HID_QUIRK_NO_EMPTY_INPUT;
 
-       td = kzalloc(sizeof(struct mt_device), GFP_KERNEL);
+       td = devm_kzalloc(&hdev->dev, sizeof(struct mt_device), GFP_KERNEL);
        if (!td) {
                dev_err(&hdev->dev, "cannot allocate multitouch data\n");
                return -ENOMEM;
@@ -980,11 +971,11 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
        td->pen_report_id = -1;
        hid_set_drvdata(hdev, td);
 
-       td->fields = kzalloc(sizeof(struct mt_fields), GFP_KERNEL);
+       td->fields = devm_kzalloc(&hdev->dev, sizeof(struct mt_fields),
+                                 GFP_KERNEL);
        if (!td->fields) {
                dev_err(&hdev->dev, "cannot allocate multitouch fields data\n");
-               ret = -ENOMEM;
-               goto fail;
+               return -ENOMEM;
        }
 
        if (id->vendor == HID_ANY_ID && id->product == HID_ANY_ID)
@@ -992,29 +983,22 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
        ret = hid_parse(hdev);
        if (ret != 0)
-               goto fail;
+               return ret;
 
        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
        if (ret)
-               goto hid_fail;
+               return ret;
 
        ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
 
        mt_set_maxcontacts(hdev);
        mt_set_input_mode(hdev);
 
-       kfree(td->fields);
+       /* release .fields memory as it is not used anymore */
+       devm_kfree(&hdev->dev, td->fields);
        td->fields = NULL;
 
        return 0;
-
-hid_fail:
-       list_for_each_entry(hi, &hdev->inputs, list)
-               mt_free_input_name(hi);
-fail:
-       kfree(td->fields);
-       kfree(td);
-       return ret;
 }
 
 #ifdef CONFIG_PM
@@ -1039,17 +1023,8 @@ static int mt_resume(struct hid_device *hdev)
 
 static void mt_remove(struct hid_device *hdev)
 {
-       struct mt_device *td = hid_get_drvdata(hdev);
-       struct hid_input *hi;
-
        sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
-       list_for_each_entry(hi, &hdev->inputs, list)
-               mt_free_input_name(hi);
-
        hid_hw_stop(hdev);
-
-       kfree(td);
-       hid_set_drvdata(hdev, NULL);
 }
 
 static const struct hid_device_id mt_devices[] = {