To optimize BLE HID devices reconnection response, we can cache the
report map so that the subsequent reconnections do not need round trip
time to read the report map.
Reviewed-by: Alain Michaud <alainm@xxxxxxxxxxxx>
---
profiles/input/hog-lib.c | 142 ++++++++++++++++++++++++++-------------
1 file changed, 96 insertions(+), 46 deletions(-)
diff --git a/profiles/input/hog-lib.c b/profiles/input/hog-lib.c
index ee811d301..1e198ea64 100644
--- a/profiles/input/hog-lib.c
+++ b/profiles/input/hog-lib.c
@@ -95,6 +95,8 @@ struct bt_hog {
struct queue *bas;
GSList *instances;
struct queue *gatt_op;
+ uint8_t report_map[HOG_REPORT_MAP_MAX_SIZE];
+ ssize_t report_map_len;
};
struct report {
@@ -276,6 +278,8 @@ static void find_included(struct bt_hog *hog, GAttrib *attrib,
free(req);
}
+static void uhid_create(struct bt_hog *hog);
+
static void report_value_cb(const guint8 *pdu, guint16 len, gpointer user_data)
{
struct report *report = user_data;
@@ -924,57 +928,17 @@ static char *item2string(char *str, uint8_t *buf, uint8_t len)
return str;
}
-static void report_map_read_cb(guint8 status, const guint8 *pdu, guint16 plen,
- gpointer user_data)
+static void uhid_create(struct bt_hog *hog)
{
- struct gatt_request *req = user_data;
- struct bt_hog *hog = req->user_data;
- uint8_t value[HOG_REPORT_MAP_MAX_SIZE];
struct uhid_event ev;
- ssize_t vlen;
- char itemstr[20]; /* 5x3 (data) + 4 (continuation) + 1 (null) */
- int i, err;
GError *gerr = NULL;
+ int i, err;
- destroy_gatt_req(req);
-
- DBG("HoG inspecting report map");
-
- if (status != 0) {
- error("Report Map read failed: %s", att_ecode2str(status));
- return;
- }
-
- vlen = dec_read_resp(pdu, plen, value, sizeof(value));
- if (vlen < 0) {
- error("ATT protocol error");
+ if (!hog->report_map_len) {
+ warn("Failed to initiate UHID_CREATE without report map");
return;
}
- DBG("Report MAP:");
- for (i = 0; i < vlen;) {
- ssize_t ilen = 0;
- bool long_item = false;
-
- if (get_descriptor_item_info(&value[i], vlen - i, &ilen,
- &long_item)) {
- /* Report ID is short item with prefix 100001xx */
- if (!long_item && (value[i] & 0xfc) == 0x84)
- hog->has_report_id = TRUE;
-
- DBG("\t%s", item2string(itemstr, &value[i], ilen));
-
- i += ilen;
- } else {
- error("Report Map parsing failed at %d", i);
-
- /* Just print remaining items at once and break */
- DBG("\t%s", item2string(itemstr, &value[i], vlen - i));
- break;
- }
- }
-
- /* create uHID device */
memset(&ev, 0, sizeof(ev));
ev.type = UHID_CREATE;
@@ -1004,8 +968,8 @@ static void report_map_read_cb(guint8 status, const guint8 *pdu, guint16 plen,
ev.u.create.version = hog->version;
ev.u.create.country = hog->bcountrycode;
ev.u.create.bus = BUS_BLUETOOTH;
- ev.u.create.rd_data = value;
- ev.u.create.rd_size = vlen;
+ ev.u.create.rd_data = hog->report_map;
+ ev.u.create.rd_size = hog->report_map_len;
err = bt_uhid_send(hog->uhid, &ev);
if (err < 0) {
@@ -1018,6 +982,62 @@ static void report_map_read_cb(guint8 status, const guint8 *pdu, guint16 plen,
bt_uhid_register(hog->uhid, UHID_SET_REPORT, set_report, hog);
hog->uhid_created = true;
+}
+
+static void report_map_read_cb(guint8 status, const guint8 *pdu, guint16 plen,
+ gpointer user_data)
+{
+ struct gatt_request *req = user_data;
+ struct bt_hog *hog = req->user_data;
+ ssize_t vlen;
+ char itemstr[20]; /* 5x3 (data) + 4 (continuation) + 1 (null) */
+ int i;
+
+ destroy_gatt_req(req);
+
+ DBG("HoG inspecting report map");
+
+ if (status != 0) {
+ error("Report Map read failed: %s", att_ecode2str(status));
+ return;
+ }
+
+ vlen = dec_read_resp(pdu, plen, hog->report_map,
+ sizeof(hog->report_map));
+ if (vlen < 0) {
+ error("ATT protocol error");
+ return;
+ }
+
+ hog->report_map_len = vlen;
+
+ DBG("Report MAP:");
+ for (i = 0; i < vlen;) {
+ ssize_t ilen = 0;
+ bool long_item = false;
+
+ if (get_descriptor_item_info(&hog->report_map[i], vlen - i,
+ &ilen, &long_item)) {
+ /* Report ID is short item with prefix 100001xx */
+ if (!long_item && (hog->report_map[i] & 0xfc) == 0x84)
+ hog->has_report_id = TRUE;
+
+ DBG("\t%s", item2string(itemstr, &hog->report_map[i],
+ ilen));
+
+ i += ilen;
+ } else {
+ error("Report Map parsing failed at %d", i);
+
+ /* Just print remaining items at once and break */
+ DBG("\t%s", item2string(itemstr, &hog->report_map[i],
+ vlen - i));
+ break;
+ }
+ }
+
+ /* create uHID device */
+ uhid_create(hog);
DBG("HoG created uHID device");
}
@@ -1602,6 +1622,12 @@ bool bt_hog_attach(struct bt_hog *hog, void *gatt)
bt_hog_attach(instance, gatt);
}
+ /* Try to initiate UHID_CREATE if we already have the report map to
+ * avoid re-reading the report map from the peer device.
+ */
+ if (hog->report_map_len > 0)
+ uhid_create(hog);
+
if (!hog->uhid_created) {
DBG("HoG discovering characteristics");
if (hog->attr)
@@ -1627,6 +1653,29 @@ bool bt_hog_attach(struct bt_hog *hog, void *gatt)
return true;
}
+static void uhid_destroy(struct bt_hog *hog)
+{
+ int err;
+ struct uhid_event ev;
+
+ if (!hog->uhid_created)
+ return;
+
+ bt_uhid_unregister_all(hog->uhid);
+
+ memset(&ev, 0, sizeof(ev));
+ ev.type = UHID_DESTROY;
+
+ err = bt_uhid_send(hog->uhid, &ev);
+
+ if (err < 0) {
+ error("bt_uhid_send: %s", strerror(-err));
+ return;
+ }
+
+ hog->uhid_created = false;
+}
+
void bt_hog_detach(struct bt_hog *hog)
{
GSList *l;
@@ -1660,6 +1709,7 @@ void bt_hog_detach(struct bt_hog *hog)
queue_foreach(hog->gatt_op, (void *) cancel_gatt_req, NULL);
g_attrib_unref(hog->attrib);
hog->attrib = NULL;
+ uhid_destroy(hog);
}
int bt_hog_set_control_point(struct bt_hog *hog, bool suspend)
--
2.26.2
