[PATCH v2 04/16] rpmsg: ctrl: implement the ioctl function to create device

[Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>]

Implement the ioctl function that parses the list of
rpmsg drivers registered to create an associated device.
To be ISO user API, in a first step, the driver_override
is only allowed for the RPMsg raw service, supported by the
rpmsg_char driver.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
 drivers/rpmsg/rpmsg_ctrl.c | 43 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c
index 065e2e304019..8381b5b2b794 100644
--- a/drivers/rpmsg/rpmsg_ctrl.c
+++ b/drivers/rpmsg/rpmsg_ctrl.c
@@ -56,12 +56,51 @@ static int rpmsg_ctrl_dev_open(struct inode *inode, struct file *filp)
 	return 0;
 }
 
+static const char *rpmsg_ctrl_get_drv_name(u32 service)
+{
+	struct rpmsg_ctl_info *drv_info;
+
+	list_for_each_entry(drv_info, &rpmsg_drv_list, node) {
+		if (drv_info->ctrl->service == service)
+			return drv_info->ctrl->drv_name;
+	}
+
+	return NULL;
+}
+
 static long rpmsg_ctrl_dev_ioctl(struct file *fp, unsigned int cmd,
 				 unsigned long arg)
 {
 	struct rpmsg_ctrl_dev *ctrldev = fp->private_data;
-
-	dev_info(&ctrldev->dev, "Control not yet implemented\n");
+	void __user *argp = (void __user *)arg;
+	struct rpmsg_channel_info chinfo;
+	struct rpmsg_endpoint_info eptinfo;
+	struct rpmsg_device *newch;
+
+	if (cmd != RPMSG_CREATE_EPT_IOCTL)
+		return -EINVAL;
+
+	if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
+		return -EFAULT;
+
+	/*
+	 * In a frst step only the rpmsg_raw service is supported.
+	 * The override is foorced to RPMSG_RAW_SERVICE
+	 */
+	chinfo.driver_override = rpmsg_ctrl_get_drv_name(RPMSG_RAW_SERVICE);
+	if (!chinfo.driver_override)
+		return -ENODEV;
+
+	memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
+	chinfo.name[RPMSG_NAME_SIZE - 1] = '\0';
+	chinfo.src = eptinfo.src;
+	chinfo.dst = eptinfo.dst;
+
+	newch = rpmsg_create_channel(ctrldev->rpdev, &chinfo);
+	if (!newch) {
+		dev_err(&ctrldev->dev, "rpmsg_create_channel failed\n");
+		return -ENXIO;
+	}
 
 	return 0;
 };
-- 
2.17.1