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>

1 files changed, 23 insertions, 48 deletions

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index cb0e361d7a4b..0fe00e2552f2 100644
--- 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[] = {