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, 130 insertions, 0 deletions

diff --git a/drivers/staging/wfx/debug.c b/drivers/staging/wfx/debug.c
index f28c94d8de89..0a328c96eaa0 100644
--- a/drivers/staging/wfx/debug.c
+++ b/drivers/staging/wfx/debug.c
@@ -7,16 +7,146 @@
  */
 #include <linux/debugfs.h>
 
+#include "debug.h"
 #include "wfx.h"
 
 #define CREATE_TRACE_POINTS
 #include "traces.h"
 
+static const struct trace_print_flags hif_msg_print_map[] = {
+	hif_msg_list,
+};
+
+static const struct trace_print_flags hif_mib_print_map[] = {
+	hif_mib_list,
+};
+
+static const struct trace_print_flags wfx_reg_print_map[] = {
+	wfx_reg_list,
+};
+
+static const char *get_symbol(unsigned long val,
+		const struct trace_print_flags *symbol_array)
+{
+	int i;
+
+	for (i = 0; symbol_array[i].mask != -1; i++) {
+		if (val == symbol_array[i].mask)
+			return symbol_array[i].name;
+	}
+
+	return "unknown";
+}
+
+const char *get_hif_name(unsigned long id)
+{
+	return get_symbol(id, hif_msg_print_map);
+}
+
+const char *get_mib_name(unsigned long id)
+{
+	return get_symbol(id, hif_mib_print_map);
+}
+
+const char *get_reg_name(unsigned long id)
+{
+	return get_symbol(id, wfx_reg_print_map);
+}
+
+struct dbgfs_hif_msg {
+	struct wfx_dev *wdev;
+	struct completion complete;
+	u8 reply[1024];
+	int ret;
+};
+
+static ssize_t wfx_send_hif_msg_write(struct file *file, const char __user *user_buf,
+				      size_t count, loff_t *ppos)
+{
+	struct dbgfs_hif_msg *context = file->private_data;
+	struct wfx_dev *wdev = context->wdev;
+	struct hif_msg *request;
+
+	if (completion_done(&context->complete)) {
+		dev_dbg(wdev->dev, "read previous result before start a new one\n");
+		return -EBUSY;
+	}
+	if (count < sizeof(struct hif_msg))
+		return -EINVAL;
+
+	// wfx_cmd_send() chekc that reply buffer is wide enough, but do not
+	// return precise length read. User have to know how many bytes should
+	// be read. Filling reply buffer with a memory pattern may help user.
+	memset(context->reply, sizeof(context->reply), 0xFF);
+	request = memdup_user(user_buf, count);
+	if (IS_ERR(request))
+		return PTR_ERR(request);
+	if (request->len != count) {
+		kfree(request);
+		return -EINVAL;
+	}
+	context->ret = wfx_cmd_send(wdev, request, context->reply, sizeof(context->reply), false);
+
+	kfree(request);
+	complete(&context->complete);
+	return count;
+}
+
+static ssize_t wfx_send_hif_msg_read(struct file *file, char __user *user_buf,
+				     size_t count, loff_t *ppos)
+{
+	struct dbgfs_hif_msg *context = file->private_data;
+	int ret;
+
+	if (count > sizeof(context->reply))
+		return -EINVAL;
+	ret = wait_for_completion_interruptible(&context->complete);
+	if (ret)
+		return ret;
+	if (context->ret < 0)
+		return context->ret;
+	// Be carefull, write() is waiting for a full message while read()
+	// only return a payload
+	ret = copy_to_user(user_buf, context->reply, count);
+	if (ret)
+		return ret;
+
+	return count;
+}
+
+static int wfx_send_hif_msg_open(struct inode *inode, struct file *file)
+{
+	struct dbgfs_hif_msg *context = kzalloc(sizeof(*context), GFP_KERNEL);
+
+	if (!context)
+		return -ENOMEM;
+	context->wdev = inode->i_private;
+	init_completion(&context->complete);
+	file->private_data = context;
+	return 0;
+}
+
+static int wfx_send_hif_msg_release(struct inode *inode, struct file *file)
+{
+	struct dbgfs_hif_msg *context = file->private_data;
+
+	kfree(context);
+	return 0;
+}
+
+static const struct file_operations wfx_send_hif_msg_fops = {
+	.open = wfx_send_hif_msg_open,
+	.release = wfx_send_hif_msg_release,
+	.write = wfx_send_hif_msg_write,
+	.read = wfx_send_hif_msg_read,
+};
+
 int wfx_debug_init(struct wfx_dev *wdev)
 {
 	struct dentry *d;
 
 	d = debugfs_create_dir("wfx", wdev->hw->wiphy->debugfsdir);
+	debugfs_create_file("send_hif_msg", 0600, d, wdev, &wfx_send_hif_msg_fops);
 
 	return 0;
 }