+/*
+ * W1 triplet callback function - used for searching ROM addresses.
+ * Registered only when controller is in 1-wire mode.
+ */
+static u8 omap_w1_triplet(void *_hdq, u8 bdir)
+{
+ u8 id_bit, comp_bit;
+ int err;
+ u8 ret = 0x3; /* no slaves responded */
+ struct hdq_data *hdq_data = _hdq;
+ u8 ctrl = OMAP_HDQ_CTRL_STATUS_SINGLE | OMAP_HDQ_CTRL_STATUS_GO |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK;
+ u8 mask = ctrl | OMAP_HDQ_CTRL_STATUS_DIR;
+
+ omap_hdq_get(_hdq);
+
+ err = mutex_lock_interruptible(&hdq_data->hdq_mutex);
+ if (err < 0) {
+ dev_dbg(hdq_data->dev, "Could not acquire mutex\n");
+ goto rtn;
+ }
+
+ hdq_data->hdq_irqstatus = 0;
+ /* read id_bit */
+ hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS,
+ ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask);
+ err = wait_event_timeout(hdq_wait_queue,
+ (hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
+ OMAP_HDQ_TIMEOUT);
+ if (err == 0) {
+ dev_dbg(hdq_data->dev, "RX wait elapsed\n");
+ goto out;
+ }
+ id_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01);
+
+ hdq_data->hdq_irqstatus = 0;
+ /* read comp_bit */
+ hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS,
+ ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask);
+ err = wait_event_timeout(hdq_wait_queue,
+ (hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
+ OMAP_HDQ_TIMEOUT);
+ if (err == 0) {
+ dev_dbg(hdq_data->dev, "RX wait elapsed\n");
+ goto out;
+ }
+ comp_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01);
+
+ if (id_bit && comp_bit) {
+ ret = 0x03; /* no slaves responded */
+ goto out;
+ }
+ if (!id_bit && !comp_bit) {
+ /* Both bits are valid, take the direction given */
+ ret = bdir ? 0x04 : 0;
+ } else {
+ /* Only one bit is valid, take that direction */
+ bdir = id_bit;
+ ret = id_bit ? 0x05 : 0x02;
+ }
+
+ /* write bdir bit */
+ hdq_reg_out(_hdq, OMAP_HDQ_TX_DATA, bdir);
+ hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, ctrl, mask);
+ err = wait_event_timeout(hdq_wait_queue,
+ (hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_TXCOMPLETE),
+ OMAP_HDQ_TIMEOUT);
+ if (err == 0) {
+ dev_dbg(hdq_data->dev, "TX wait elapsed\n");
+ goto out;
+ }
+
+ hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, 0,
+ OMAP_HDQ_CTRL_STATUS_SINGLE);
+
+out:
+ mutex_unlock(&hdq_data->hdq_mutex);
+rtn:
+ omap_hdq_put(_hdq);
+ return ret;
+}
+
+/* reset callback */
+static u8 omap_w1_reset_bus(void *_hdq)
+{
+ omap_hdq_get(_hdq);
+ omap_hdq_break(_hdq);
+ omap_hdq_put(_hdq);
+ return 0;
+}
+