staging: wfx: allow to send commands to chip

Chip has multiple input buffers and can handle multiple 802.11 frames
in parallel. However, other HIF command must be sent sequentially.
wsm_send_cmd() handles these requests.

This commit also add send_hif_cmd in debugfs. This file allows to send
arbitrary commands to chip. It can be used for debug and testing.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20190919142527.31797-12-Jerome.Pouiller@silabs.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 45 insertions, 0 deletions

diff --git a/drivers/staging/wfx/hif_rx.c b/drivers/staging/wfx/hif_rx.c
index 5c207e6d4348..ba8ea4f3c91b 100644
--- a/drivers/staging/wfx/hif_rx.c
+++ b/drivers/staging/wfx/hif_rx.c
@@ -13,6 +13,43 @@
 #include "wfx.h"
 #include "hif_api_cmd.h"
 
+static int hif_generic_confirm(struct wfx_dev *wdev, struct hif_msg *hif, void *buf)
+{
+	// All confirm messages start with status
+	int status = le32_to_cpu(*((__le32 *) buf));
+	int cmd = hif->id;
+	int len = hif->len - 4; // drop header
+
+	WARN(!mutex_is_locked(&wdev->hif_cmd.lock), "data locking error");
+
+	if (!wdev->hif_cmd.buf_send) {
+		dev_warn(wdev->dev, "unexpected confirmation: 0x%.2x\n", cmd);
+		return -EINVAL;
+	}
+
+	if (cmd != wdev->hif_cmd.buf_send->id) {
+		dev_warn(wdev->dev, "chip response mismatch request: 0x%.2x vs 0x%.2x\n",
+			 cmd, wdev->hif_cmd.buf_send->id);
+		return -EINVAL;
+	}
+
+	if (wdev->hif_cmd.buf_recv) {
+		if (wdev->hif_cmd.len_recv >= len)
+			memcpy(wdev->hif_cmd.buf_recv, buf, len);
+		else
+			status = -ENOMEM;
+	}
+	wdev->hif_cmd.ret = status;
+
+	if (!wdev->hif_cmd.async) {
+		complete(&wdev->hif_cmd.done);
+	} else {
+		wdev->hif_cmd.buf_send = NULL;
+		mutex_unlock(&wdev->hif_cmd.lock);
+	}
+	return status;
+}
+
 static int hif_startup_indication(struct wfx_dev *wdev, struct hif_msg *hif, void *buf)
 {
 	struct hif_ind_startup *body = buf;
@@ -44,6 +81,14 @@ void wfx_handle_rx(struct wfx_dev *wdev, struct sk_buff *skb)
 	struct hif_msg *hif = (struct hif_msg *) skb->data;
 	int hif_id = hif->id;
 
+	// Note: mutex_is_lock cause an implicit memory barrier that protect
+	// buf_send
+	if (mutex_is_locked(&wdev->hif_cmd.lock)
+	    && wdev->hif_cmd.buf_send
+	    && wdev->hif_cmd.buf_send->id == hif_id) {
+		hif_generic_confirm(wdev, hif, hif->body);
+		goto free;
+	}
 	for (i = 0; i < ARRAY_SIZE(hif_handlers); i++) {
 		if (hif_handlers[i].msg_id == hif_id) {
 			if (hif_handlers[i].handler)