Changeset c657bd7 in mainline for uspace/drv/hid/ps2mouse/ps2mouse.c

Timestamp:

2017-11-20T10:06:59Z (8 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

19ea61d

Parents:

5d50c419

git-author:

Jiri Svoboda <jiri@…> (2017-11-19 22:05:26)

git-committer:

Jiri Svoboda <jiri@…> (2017-11-20 10:06:59)

Message:

Less is sometimes more. Need chardev_read to be able to return less bytes than requested if less is available. Otherwise cannot read variable-sized packets except yte-by-byte.

File:

• uspace/drv/hid/ps2mouse/ps2mouse.c (modified) (5 diffs)

uspace/drv/hid/ps2mouse/ps2mouse.c

@@ -212 +212 @@
 }
 
+/** Read fixed-size mouse packet.
+ *
+ * Continue reading until entire packet is received.
+ *
+ * @param mouse Mouse device
+ * @param pbuf Buffer for storing packet
+ * @param psize Packet size
+ *
+ * @return EOK on success or non-zero error code
+ */
+static int ps2_mouse_read_packet(ps2_mouse_t *mouse, void *pbuf, size_t psize)
+{
+        int rc;
+        size_t pos;
+        size_t nread;
+
+        pos = 0;
+        while (pos < psize) {
+                rc = chardev_read(mouse->chardev, pbuf + pos, psize - pos,
+                    &nread);
+                if (rc != EOK) {
+                        ddf_msg(LVL_WARN, "Error reading packet.");
+                        return rc;
+                }
+
+                pos += nread;
+        }
+
+        return EOK;
+}
+
 /** Get data and parse ps2 protocol packets.
  * @param arg Pointer to ps2_mouse_t structure.
@@ -219 +250 @@
 {
         ps2_mouse_t *mouse = (ps2_mouse_t *) arg;
-        size_t nread;
         int rc;
 
@@ -225 +255 @@
         while (1) {
                 uint8_t packet[PS2_BUFSIZE] = {};
-                rc = chardev_read(mouse->chardev, packet, PS2_BUFSIZE, &nread);
-                if (rc != EOK || nread != PS2_BUFSIZE) {
-                        ddf_msg(LVL_WARN, "Incorrect packet size: %zd.", nread);
+                rc = ps2_mouse_read_packet(mouse, packet, PS2_BUFSIZE);
+                if (rc != EOK)
                         continue;
-                }
 
                 ddf_msg(LVL_DEBUG2, "Got packet: %hhx:%hhx:%hhx.",
@@ -274 +302 @@
 {
         ps2_mouse_t *mouse = (ps2_mouse_t *) arg;
-        size_t nread;
         int rc;
 
@@ -280 +307 @@
         while (1) {
                 uint8_t packet[INTELLIMOUSE_BUFSIZE] = {};
-                rc = chardev_read(mouse->chardev, packet, INTELLIMOUSE_BUFSIZE,
-                    &nread);
-                if (rc != EOK || nread != INTELLIMOUSE_BUFSIZE) {
-                        ddf_msg(LVL_WARN, "Incorrect packet size: %zd.", nread);
+                rc = ps2_mouse_read_packet(mouse, packet, INTELLIMOUSE_BUFSIZE);
+                if (rc != EOK)
                         continue;
-                }
+
                 ddf_msg(LVL_DEBUG2, "Got packet: %hhx:%hhx:%hhx:%hhx.",
                     packet[0], packet[1], packet[2], packet[3]);