[RFC v2 2/2] xhci: refactor handle_cmd_completion() switch branches into functions

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This patch refactors the switch statement in handle_cmd_completion() by
creating a separate function for each branch, named 'xhci_handle_cmd_<type>'.

Other changes introduced by this patch are:

- Renaming the already existed functions by adding the prefix
  'xhci_handle_cmd_' for consistency. Also, for handle_stopped_endpoint()
  the order of arguments was changed too, so that the prototype of
  'xhci_handle_cmd_' be similar and easy to follow.
- Additional local variables were added, such as cmd_trb, cmd_comp_code,
  cmd_type, add_flags and drop_flags, and the label 'update_ring',
  mainly to reduce code dublication and line length.
- The variable ep_ring, that was assigned in the case TRB_CONFIG_EP
  but never used, was removed.

Signed-off-by: Xenia Ragiadakou <burzalodowa@xxxxxxxxx>
---

Differences from version 1:

Create separate functions for each switch case branch, instead of a single
function holding the entire switch

 drivers/usb/host/xhci-ring.c | 310 ++++++++++++++++++++++++++-----------------
 1 file changed, 185 insertions(+), 125 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index ddbda35..bc9ce03 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -755,8 +755,8 @@ static void xhci_giveback_urb_in_irq(struct xhci_hcd *xhci,
  *  2. Otherwise, we turn all the TRBs in the TD into No-op TRBs (with the chain
  *     bit cleared) so that the HW will skip over them.
  */
-static void handle_stopped_endpoint(struct xhci_hcd *xhci,
-		union xhci_trb *trb, struct xhci_event_cmd *event)
+static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, union xhci_trb *trb)
 {
 	unsigned int slot_id;
 	unsigned int ep_index;
@@ -1063,9 +1063,8 @@ static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
  * endpoint doorbell to restart the ring, but only if there aren't more
  * cancellations pending.
  */
-static void handle_set_deq_completion(struct xhci_hcd *xhci,
-		struct xhci_event_cmd *event,
-		union xhci_trb *trb)
+static void xhci_handle_cmd_set_deq(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, union xhci_trb *trb)
 {
 	unsigned int slot_id;
 	unsigned int ep_index;
@@ -1157,9 +1156,8 @@ static void handle_set_deq_completion(struct xhci_hcd *xhci,
 	ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
 }
 
-static void handle_reset_ep_completion(struct xhci_hcd *xhci,
-		struct xhci_event_cmd *event,
-		union xhci_trb *trb)
+static void xhci_handle_cmd_reset_ep(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, union xhci_trb *trb)
 {
 	int slot_id;
 	unsigned int ep_index;
@@ -1372,21 +1370,160 @@ static int handle_stopped_cmd_ring(struct xhci_hcd *xhci,
 	return cur_trb_is_good;
 }
 
-static void handle_cmd_completion(struct xhci_hcd *xhci,
+static void xhci_handle_cmd_enable_slot(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, u32 cmd_comp_code)
+{
+	int slot_id;
+
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	if (cmd_comp_code == COMP_SUCCESS)
+		xhci->slot_id = slot_id;
+	else
+		xhci->slot_id = 0;
+	complete(&xhci->addr_dev);
+}
+
+static void xhci_handle_cmd_disable_slot(struct xhci_hcd *xhci,
 		struct xhci_event_cmd *event)
 {
-	int slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
-	u64 cmd_dma;
-	dma_addr_t cmd_dequeue_dma;
-	struct xhci_input_control_ctx *ctrl_ctx;
+	int slot_id;
 	struct xhci_virt_device *virt_dev;
+
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	virt_dev = xhci->devs[slot_id];
+	if (!virt_dev)
+		return;
+	if (xhci->quirks & XHCI_EP_LIMIT_QUIRK)
+		/* Delete default control endpoint resources */
+		xhci_free_device_endpoint_resources(xhci, virt_dev, true);
+	xhci_free_virt_device(xhci, slot_id);
+}
+
+static void xhci_handle_cmd_config_ep(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, u32 cmd_comp_code)
+{
+	int slot_id;
+	struct xhci_virt_device *virt_dev;
+	struct xhci_input_control_ctx *ctrl_ctx;
 	unsigned int ep_index;
-	struct xhci_ring *ep_ring;
 	unsigned int ep_state;
+	u32 add_flags, drop_flags;
+
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	virt_dev = xhci->devs[slot_id];
+	if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
+		return;
+	/*
+	 * Configure endpoint commands can come from the USB core
+	 * configuration or alt setting changes, or because the HW
+	 * needed an extra configure endpoint command after a reset
+	 * endpoint command or streams were being configured.
+	 * If the command was for a halted endpoint, the xHCI driver
+	 * is not waiting on the configure endpoint command.
+	 */
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
+	if (!ctrl_ctx) {
+		xhci_warn(xhci, "Could not get input context, bad type.\n");
+		return;
+	}
+	add_flags = le32_to_cpu(ctrl_ctx->add_flags);
+	drop_flags = le32_to_cpu(ctrl_ctx->drop_flags);
+	/* Input ctx add_flags are the endpoint index plus one */
+	ep_index = xhci_last_valid_endpoint(add_flags) - 1;
+	/* A usb_set_interface() call directly after clearing a halted
+	 * condition may race on this quirky hardware.  Not worth
+	 * worrying about, since this is prototype hardware.  Not sure
+	 * if this will work for streams, but streams support was
+	 * untested on this prototype.
+	 */
+	if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
+			ep_index != (unsigned int) -1 &&
+			add_flags - SLOT_FLAG == drop_flags) {
+		ep_state = virt_dev->eps[ep_index].ep_state;
+		if (!(ep_state & EP_HALTED))
+			goto bandwidth_change;
+		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
+				"Completed config ep cmd - "
+				"last ep index = %d, state = %d",
+				ep_index, ep_state);
+		/* Clear internal halted state and restart ring(s) */
+		virt_dev->eps[ep_index].ep_state &= ~EP_HALTED;
+		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
+		return;
+	}
+bandwidth_change:
+	xhci_dbg_trace(xhci,  trace_xhci_dbg_context_change,
+			"Completed config ep cmd");
+	virt_dev->cmd_status = cmd_comp_code;
+	complete(&virt_dev->cmd_completion);
+}
+
+static void xhci_handle_cmd_eval_ctx(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, u32 cmd_comp_code)
+{
+	int slot_id;
+	struct xhci_virt_device *virt_dev;
+
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	virt_dev = xhci->devs[slot_id];
+	if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
+		return;
+	virt_dev->cmd_status = cmd_comp_code;
+	complete(&virt_dev->cmd_completion);
+}
+
+static void xhci_handle_cmd_addr_dev(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event, u32 cmd_comp_code)
+{
+	int slot_id;
+
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	xhci->devs[slot_id]->cmd_status = cmd_comp_code;
+	complete(&xhci->addr_dev);
+}
+
+static void xhci_handle_cmd_reset_dev(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event)
+{
+	int slot_id;
+	struct xhci_virt_device *virt_dev;
+
+	xhci_dbg(xhci, "Completed reset device command.\n");
+	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
+	virt_dev = xhci->devs[slot_id];
+	if (virt_dev)
+		handle_cmd_in_cmd_wait_list(xhci, virt_dev, event);
+	else
+		xhci_warn(xhci, "Reset device command completion "
+				"for disabled slot %u\n", slot_id);
+}
+
+static void xhci_handle_cmd_nec_get_fw(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event)
+{
+	if (!(xhci->quirks & XHCI_NEC_HOST)) {
+		xhci->error_bitmask |= 1 << 6;
+		return;
+	}
+	xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
+			"NEC firmware version %2x.%02x",
+			 NEC_FW_MAJOR(le32_to_cpu(event->status)),
+			 NEC_FW_MINOR(le32_to_cpu(event->status)));
+}
+
+static void handle_cmd_completion(struct xhci_hcd *xhci,
+		struct xhci_event_cmd *event)
+{
+	u64 cmd_dma;
+	dma_addr_t cmd_dequeue_dma;
+	union xhci_trb *cmd_trb;
+	u32 cmd_comp_code;
+	u32 cmd_type;
 
 	cmd_dma = le64_to_cpu(event->cmd_trb);
+	cmd_trb = xhci->cmd_ring->dequeue;
 	cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
-			xhci->cmd_ring->dequeue);
+						cmd_trb);
 	/* Is the command ring deq ptr out of sync with the deq seg ptr? */
 	if (cmd_dequeue_dma == 0) {
 		xhci->error_bitmask |= 1 << 4;
@@ -1398,142 +1535,65 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
 		return;
 	}
 
-	trace_xhci_cmd_completion(&xhci->cmd_ring->dequeue->generic,
-					(struct xhci_generic_trb *) event);
+	trace_xhci_cmd_completion(cmd_trb, (struct xhci_generic_trb *) event);
 
-	if ((GET_COMP_CODE(le32_to_cpu(event->status)) == COMP_CMD_ABORT) ||
-		(GET_COMP_CODE(le32_to_cpu(event->status)) == COMP_CMD_STOP)) {
+	cmd_comp_code = GET_COMP_CODE(le32_to_cpu(event->status));
+	if (cmd_comp_code == COMP_CMD_ABORT || cmd_comp_code == COMP_CMD_STOP) {
 		/* If the return value is 0, we think the trb pointed by
 		 * command ring dequeue pointer is a good trb. The good
 		 * trb means we don't want to cancel the trb, but it have
 		 * been stopped by host. So we should handle it normally.
 		 * Otherwise, driver should invoke inc_deq() and return.
 		 */
-		if (handle_stopped_cmd_ring(xhci,
-				GET_COMP_CODE(le32_to_cpu(event->status)))) {
-			inc_deq(xhci, xhci->cmd_ring);
-			return;
-		}
+		if (handle_stopped_cmd_ring(xhci, cmd_comp_code))
+			goto update_ring;
 	}
 
-	switch (le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3])
-		& TRB_TYPE_BITMASK) {
-	case TRB_TYPE(TRB_ENABLE_SLOT):
-		if (GET_COMP_CODE(le32_to_cpu(event->status)) == COMP_SUCCESS)
-			xhci->slot_id = slot_id;
-		else
-			xhci->slot_id = 0;
-		complete(&xhci->addr_dev);
+	cmd_type = TRB_FIELD_TO_TYPE(le32_to_cpu(cmd_trb->generic.field[3]));
+
+	switch (cmd_type) {
+
+	case TRB_ENABLE_SLOT:
+		xhci_handle_cmd_enable_slot(xhci, event, cmd_comp_code);
 		break;
-	case TRB_TYPE(TRB_DISABLE_SLOT):
-		if (xhci->devs[slot_id]) {
-			if (xhci->quirks & XHCI_EP_LIMIT_QUIRK)
-				/* Delete default control endpoint resources */
-				xhci_free_device_endpoint_resources(xhci,
-						xhci->devs[slot_id], true);
-			xhci_free_virt_device(xhci, slot_id);
-		}
+	case TRB_DISABLE_SLOT:
+		xhci_handle_cmd_disable_slot(xhci, event);
 		break;
-	case TRB_TYPE(TRB_CONFIG_EP):
-		virt_dev = xhci->devs[slot_id];
-		if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
-			break;
-		/*
-		 * Configure endpoint commands can come from the USB core
-		 * configuration or alt setting changes, or because the HW
-		 * needed an extra configure endpoint command after a reset
-		 * endpoint command or streams were being configured.
-		 * If the command was for a halted endpoint, the xHCI driver
-		 * is not waiting on the configure endpoint command.
-		 */
-		ctrl_ctx = xhci_get_input_control_ctx(xhci,
-				virt_dev->in_ctx);
-		if (!ctrl_ctx) {
-			xhci_warn(xhci, "Could not get input context, bad type.\n");
-			break;
-		}
-		/* Input ctx add_flags are the endpoint index plus one */
-		ep_index = xhci_last_valid_endpoint(le32_to_cpu(ctrl_ctx->add_flags)) - 1;
-		/* A usb_set_interface() call directly after clearing a halted
-		 * condition may race on this quirky hardware.  Not worth
-		 * worrying about, since this is prototype hardware.  Not sure
-		 * if this will work for streams, but streams support was
-		 * untested on this prototype.
-		 */
-		if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
-				ep_index != (unsigned int) -1 &&
-		    le32_to_cpu(ctrl_ctx->add_flags) - SLOT_FLAG ==
-		    le32_to_cpu(ctrl_ctx->drop_flags)) {
-			ep_ring = xhci->devs[slot_id]->eps[ep_index].ring;
-			ep_state = xhci->devs[slot_id]->eps[ep_index].ep_state;
-			if (!(ep_state & EP_HALTED))
-				goto bandwidth_change;
-			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
-					"Completed config ep cmd - "
-					"last ep index = %d, state = %d",
-					ep_index, ep_state);
-			/* Clear internal halted state and restart ring(s) */
-			xhci->devs[slot_id]->eps[ep_index].ep_state &=
-				~EP_HALTED;
-			ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
-			break;
-		}
-bandwidth_change:
-		xhci_dbg_trace(xhci,  trace_xhci_dbg_context_change,
-				"Completed config ep cmd");
-		xhci->devs[slot_id]->cmd_status =
-			GET_COMP_CODE(le32_to_cpu(event->status));
-		complete(&xhci->devs[slot_id]->cmd_completion);
+	case TRB_CONFIG_EP:
+		xhci_handle_cmd_config_ep(xhci, event, cmd_comp_code);
 		break;
-	case TRB_TYPE(TRB_EVAL_CONTEXT):
-		virt_dev = xhci->devs[slot_id];
-		if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
-			break;
-		xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(le32_to_cpu(event->status));
-		complete(&xhci->devs[slot_id]->cmd_completion);
+	case TRB_EVAL_CONTEXT:
+		xhci_handle_cmd_eval_ctx(xhci, event, cmd_comp_code);
 		break;
-	case TRB_TYPE(TRB_ADDR_DEV):
-		xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(le32_to_cpu(event->status));
-		complete(&xhci->addr_dev);
+	case TRB_ADDR_DEV:
+		xhci_handle_cmd_addr_dev(xhci, event, cmd_comp_code);
 		break;
-	case TRB_TYPE(TRB_STOP_RING):
-		handle_stopped_endpoint(xhci, xhci->cmd_ring->dequeue, event);
+	case TRB_STOP_RING:
+		xhci_handle_cmd_stop_ep(xhci, event, cmd_trb);
 		break;
-	case TRB_TYPE(TRB_SET_DEQ):
-		handle_set_deq_completion(xhci, event, xhci->cmd_ring->dequeue);
+	case TRB_SET_DEQ:
+		xhci_handle_cmd_set_deq(xhci, event, cmd_trb);
 		break;
-	case TRB_TYPE(TRB_CMD_NOOP):
+	case TRB_CMD_NOOP:
 		break;
-	case TRB_TYPE(TRB_RESET_EP):
-		handle_reset_ep_completion(xhci, event, xhci->cmd_ring->dequeue);
+	case TRB_RESET_EP:
+		xhci_handle_cmd_reset_ep(xhci, event, cmd_trb);
 		break;
-	case TRB_TYPE(TRB_RESET_DEV):
-		xhci_dbg(xhci, "Completed reset device command.\n");
-		slot_id = TRB_TO_SLOT_ID(
-			le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3]));
-		virt_dev = xhci->devs[slot_id];
-		if (virt_dev)
-			handle_cmd_in_cmd_wait_list(xhci, virt_dev, event);
-		else
-			xhci_warn(xhci, "Reset device command completion "
-					"for disabled slot %u\n", slot_id);
+	case TRB_RESET_DEV:
+		xhci_handle_cmd_reset_dev(xhci, event);
 		break;
-	case TRB_TYPE(TRB_NEC_GET_FW):
-		if (!(xhci->quirks & XHCI_NEC_HOST)) {
-			xhci->error_bitmask |= 1 << 6;
-			break;
-		}
-		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
-			"NEC firmware version %2x.%02x",
-			 NEC_FW_MAJOR(le32_to_cpu(event->status)),
-			 NEC_FW_MINOR(le32_to_cpu(event->status)));
+	case TRB_NEC_GET_FW:
+		xhci_handle_cmd_nec_get_fw(xhci, event);
 		break;
 	default:
 		/* Skip over unknown commands on the event ring */
 		xhci->error_bitmask |= 1 << 6;
 		break;
 	}
+
+update_ring:
 	inc_deq(xhci, xhci->cmd_ring);
+	return;
 }
 
 static void handle_vendor_event(struct xhci_hcd *xhci,
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux