Re: [PATCH v7 04/13] slimbus: core: Add slim controllers support

From: Srinivas Kandagatla
Date: Mon Nov 20 2017 - 01:48:10 EST




On 17/11/17 08:13, Greg KH wrote:
On Fri, Nov 17, 2017 at 10:12:22AM +0530, Vinod Koul wrote:
On Thu, Nov 16, 2017 at 05:29:35PM +0000, Srinivas Kandagatla wrote:
thanks for the comments.


On 16/11/17 16:42, Vinod Koul wrote:
On Wed, Nov 15, 2017 at 02:10:34PM +0000,srinivas.kandagatla@xxxxxxxxxx wrote:

+static void slim_dev_release(struct device *dev)
+{
+ struct slim_device *sbdev = to_slim_device(dev);
+
+ put_device(sbdev->ctrl->dev);
which device would that be?
This is controller device

+static int slim_add_device(struct slim_controller *ctrl,
+ struct slim_device *sbdev,
+ struct device_node *node)
+{
+ sbdev->dev.bus = &slimbus_bus;
+ sbdev->dev.parent = ctrl->dev;
+ sbdev->dev.release = slim_dev_release;
+ sbdev->dev.driver = NULL;
+ sbdev->ctrl = ctrl;
+
+ dev_set_name(&sbdev->dev, "%x:%x:%x:%x",
+ sbdev->e_addr.manf_id,
+ sbdev->e_addr.prod_code,
+ sbdev->e_addr.dev_index,
+ sbdev->e_addr.instance);
+
+ get_device(ctrl->dev);
is this controller device and you ensuring it doesnt go away while you have
slaves on it?
Yes.
I thought since you are marking ctrl->dev as parent, the device core should
ensure that parent doesn't go off when you have child device?

Greg, is that understanding correct, if so we may not need these calls.
That understanding should be correct, as the reference count is
incremented on the parent when a child is added.

It would be trivial for this to be tested, and yes, I am pretty sure you
don't need this call.


Thanks for suggestion, I will remove this in next version.


thanks,
srini