hid-multitouch: WIP: create sysfs attribute to control quirks from user-space

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>

diff --git a/Documentation/ABI/testing/sysfs-driver-hid-multitouch b/Documentation/ABI/testing/sysfs-driver-hid-multitouch
new file mode 100644 (file)
index 0000000..57f26f7
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-hid-multitouch
@@ -0,0 +1,9 @@
+What:          /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/quirks
+Date:          November 2011
+Contact:       Benjamin Tissoires <benjamin.tissoires@gmail.com>
+Description:   The hexadecimal value of this attribute corresponds to the
+               quirks actually in place to handle the device's protocol.
+               When read, this attribute returns the current settings (see
+               MT_QUIRKS_* in hid-multitouch.c).
+               When written this attribute change on the fly the quirks, then
+               the protocol to handle the device.

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 5b93548..e1d9321 100644 (file)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -60,9 +60,19 @@ struct mt_slot {
        bool seen_in_this_frame;/* has this slot been updated */
 };
 
+struct mt_class {
+       __s32 name;     /* MT_CLS */
+       __s32 quirks;
+       __s32 sn_move;  /* Signal/noise ratio for move events */
+       __s32 sn_width; /* Signal/noise ratio for width events */
+       __s32 sn_height;        /* Signal/noise ratio for height events */
+       __s32 sn_pressure;      /* Signal/noise ratio for pressure events */
+       __u8 maxcontacts;
+};
+
 struct mt_device {
        struct mt_slot curdata; /* placeholder of incoming data */
-       struct mt_class *mtclass;       /* our mt device class */
+       struct mt_class mtclass;        /* our mt device class */
        unsigned last_field_index;      /* last field index of the report */
        unsigned last_slot_field;       /* the last field of a slot */
        int last_mt_collection; /* last known mt-related collection */
@@ -74,16 +84,6 @@ struct mt_device {
        struct mt_slot *slots;
 };
 
-struct mt_class {
-       __s32 name;     /* MT_CLS */
-       __s32 quirks;
-       __s32 sn_move;  /* Signal/noise ratio for move events */
-       __s32 sn_width; /* Signal/noise ratio for width events */
-       __s32 sn_height;        /* Signal/noise ratio for height events */
-       __s32 sn_pressure;      /* Signal/noise ratio for pressure events */
-       __u8 maxcontacts;
-};
-
 /* classes of device behavior */
 #define MT_CLS_DEFAULT                         0x0001
 
@@ -181,6 +181,44 @@ struct mt_class mt_classes[] = {
        { }
 };
 
+static ssize_t mt_show_quirks(struct device *dev,
+                          struct device_attribute *attr,
+                          char *buf)
+{
+       struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+       struct mt_device *td = hid_get_drvdata(hdev);
+
+       return sprintf(buf, "%u\n", td->mtclass.quirks);
+}
+
+static ssize_t mt_set_quirks(struct device *dev,
+                         struct device_attribute *attr,
+                         const char *buf, size_t count)
+{
+       struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+       struct mt_device *td = hid_get_drvdata(hdev);
+
+       unsigned long val;
+
+       if (strict_strtoul(buf, 0, &val))
+               return -EINVAL;
+
+       td->mtclass.quirks = val;
+
+       return count;
+}
+
+static DEVICE_ATTR(quirks, S_IWUSR | S_IRUGO, mt_show_quirks, mt_set_quirks);
+
+static struct attribute *sysfs_attrs[] = {
+       &dev_attr_quirks.attr,
+       NULL
+};
+
+static struct attribute_group mt_attribute_group = {
+       .attrs = sysfs_attrs
+};
+
 static void mt_feature_mapping(struct hid_device *hdev,
                struct hid_field *field, struct hid_usage *usage)
 {
@@ -192,9 +230,9 @@ static void mt_feature_mapping(struct hid_device *hdev,
                break;
        case HID_DG_CONTACTMAX:
                td->maxcontacts = field->value[0];
-               if (td->mtclass->maxcontacts)
+               if (td->mtclass.maxcontacts)
                        /* check if the maxcontacts is given by the class */
-                       td->maxcontacts = td->mtclass->maxcontacts;
+                       td->maxcontacts = td->mtclass.maxcontacts;
 
                break;
        }
@@ -214,7 +252,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
                unsigned long **bit, int *max)
 {
        struct mt_device *td = hid_get_drvdata(hdev);
-       struct mt_class *cls = td->mtclass;
+       struct mt_class *cls = &td->mtclass;
        __s32 quirks = cls->quirks;
 
        /* Only map fields from TouchScreen or TouchPad collections.
@@ -363,7 +401,7 @@ static int mt_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 
 static int mt_compute_slot(struct mt_device *td)
 {
-       __s32 quirks = td->mtclass->quirks;
+       __s32 quirks = td->mtclass.quirks;
 
        if (quirks & MT_QUIRK_SLOT_IS_CONTACTID)
                return td->curdata.contactid;
@@ -407,7 +445,7 @@ static void mt_emit_event(struct mt_device *td, struct input_dev *input)
 
        for (i = 0; i < td->maxcontacts; ++i) {
                struct mt_slot *s = &(td->slots[i]);
-               if ((td->mtclass->quirks & MT_QUIRK_NOT_SEEN_MEANS_UP) &&
+               if ((td->mtclass.quirks & MT_QUIRK_NOT_SEEN_MEANS_UP) &&
                        !s->seen_in_this_frame) {
                        s->touch_state = false;
                }
@@ -444,7 +482,7 @@ static int mt_event(struct hid_device *hid, struct hid_field *field,
                                struct hid_usage *usage, __s32 value)
 {
        struct mt_device *td = hid_get_drvdata(hid);
-       __s32 quirks = td->mtclass->quirks;
+       __s32 quirks = td->mtclass.quirks;
 
        if (hid->claimed & HID_CLAIMED_INPUT && td->slots) {
                switch (usage->hid) {
@@ -552,7 +590,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
                dev_err(&hdev->dev, "cannot allocate multitouch data\n");
                return -ENOMEM;
        }
-       td->mtclass = mtclass;
+       td->mtclass = *mtclass;
        td->inputmode = -1;
        td->last_mt_collection = -1;
        hid_set_drvdata(hdev, td);
@@ -574,6 +612,8 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
                goto fail;
        }
 
+       ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
+
        mt_set_input_mode(hdev);
 
        return 0;
@@ -594,6 +634,7 @@ static int mt_reset_resume(struct hid_device *hdev)
 static void mt_remove(struct hid_device *hdev)
 {
        struct mt_device *td = hid_get_drvdata(hdev);
+       sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
        hid_hw_stop(hdev);
        kfree(td->slots);
        kfree(td);