LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Viresh Kumar <viresh.kumar@linaro.org>
To: Jason Wang <jasowang@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Rob Herring <robh+dt@kernel.org>, Arnd Bergmann <arnd@kernel.org>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: "Viresh Kumar" <viresh.kumar@linaro.org>,
	"Vincent Guittot" <vincent.guittot@linaro.org>,
	"Bill Mills" <bill.mills@linaro.org>,
	"Alex Bennée" <alex.bennee@linaro.org>,
	"Enrico Weigelt, metux IT consult" <info@metux.net>,
	"Jie Deng" <jie.deng@intel.com>,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	"Arnd Bergmann" <arnd@arndb.de>
Subject: [PATCH V4 5/5] virtio: Bind virtio device to device-tree node
Date: Tue, 27 Jul 2021 10:53:52 +0530	[thread overview]
Message-ID: <94c12705602929968477aaf27e02439eb7a7f253.1627362340.git.viresh.kumar@linaro.org> (raw)
In-Reply-To: <cover.1627362340.git.viresh.kumar@linaro.org>

Bind the virtio devices with their of_node. This will help users of the
virtio devices to mention their dependencies on the device in the DT
itself. Like GPIO pin users can use the phandle of the device node, or
the node may contain more subnodes to add i2c or spi eeproms and other
users.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/virtio/virtio.c | 57 ++++++++++++++++++++++++++++++++++++++---
 1 file changed, 54 insertions(+), 3 deletions(-)

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 4b15c00c0a0a..5f80786c2aa2 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -4,6 +4,7 @@
 #include <linux/virtio_config.h>
 #include <linux/module.h>
 #include <linux/idr.h>
+#include <linux/of.h>
 #include <uapi/linux/virtio_ids.h>
 
 /* Unique numbering for virtio devices. */
@@ -292,6 +293,9 @@ static int virtio_dev_remove(struct device *_d)
 
 	/* Acknowledge the device's existence again. */
 	virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+
+	of_node_put(dev->dev.of_node);
+
 	return 0;
 }
 
@@ -319,6 +323,43 @@ void unregister_virtio_driver(struct virtio_driver *driver)
 }
 EXPORT_SYMBOL_GPL(unregister_virtio_driver);
 
+static int virtio_device_of_init(struct virtio_device *dev)
+{
+	struct device_node *np, *pnode = dev_of_node(dev->dev.parent);
+	char compat[] = "virtio,deviceXXXXXXXX";
+	int ret, count;
+
+	if (!pnode)
+		return 0;
+
+	count = of_get_available_child_count(pnode);
+	if (!count)
+		return 0;
+
+	/* There can be only 1 child node */
+	if (WARN_ON(count > 1))
+		return -EINVAL;
+
+	np = of_get_next_available_child(pnode, NULL);
+	if (WARN_ON(!np))
+		return -ENODEV;
+
+	ret = snprintf(compat, sizeof(compat), "virtio,device%x", dev->id.device);
+	BUG_ON(ret >= sizeof(compat));
+
+	if (!of_device_is_compatible(np, compat)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	dev->dev.of_node = np;
+	return 0;
+
+out:
+	of_node_put(np);
+	return ret;
+}
+
 /**
  * register_virtio_device - register virtio device
  * @dev        : virtio device to be registered
@@ -343,6 +384,10 @@ int register_virtio_device(struct virtio_device *dev)
 	dev->index = err;
 	dev_set_name(&dev->dev, "virtio%u", dev->index);
 
+	err = virtio_device_of_init(dev);
+	if (err)
+		goto out_ida_remove;
+
 	spin_lock_init(&dev->config_lock);
 	dev->config_enabled = false;
 	dev->config_change_pending = false;
@@ -362,10 +407,16 @@ int register_virtio_device(struct virtio_device *dev)
 	 */
 	err = device_add(&dev->dev);
 	if (err)
-		ida_simple_remove(&virtio_index_ida, dev->index);
+		goto out_of_node_put;
+
+	return 0;
+
+out_of_node_put:
+	of_node_put(dev->dev.of_node);
+out_ida_remove:
+	ida_simple_remove(&virtio_index_ida, dev->index);
 out:
-	if (err)
-		virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
+	virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
 	return err;
 }
 EXPORT_SYMBOL_GPL(register_virtio_device);
-- 
2.31.1.272.g89b43f80a514


  parent reply	other threads:[~2021-07-27  5:24 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-27  5:23 [PATCH V4 0/5] virtio: Add virtio-device bindings Viresh Kumar
2021-07-27  5:23 ` [PATCH V4 1/5] dt-bindings: virtio: Add binding for virtio devices Viresh Kumar
2021-07-27  7:51   ` Arnd Bergmann
2021-08-02 19:40   ` Rob Herring
2021-07-27  5:23 ` [PATCH V4 2/5] dt-bindings: i2c: Add bindings for i2c-virtio Viresh Kumar
2021-08-02 19:41   ` Rob Herring
2021-07-27  5:23 ` [PATCH V4 3/5] dt-bindings: gpio: Add bindings for gpio-virtio Viresh Kumar
2021-08-02 19:40   ` Rob Herring
2021-08-03  4:30     ` Viresh Kumar
2021-08-03 15:47       ` Rob Herring
2021-08-04  3:49         ` Viresh Kumar
2021-07-27  5:23 ` [PATCH V4 4/5] uapi: virtio_ids: Sync ids with specification Viresh Kumar
2021-07-27  5:23 ` Viresh Kumar [this message]
2021-08-04  3:56 ` [PATCH V4 0/5] virtio: Add virtio-device bindings Viresh Kumar
2021-08-11  5:38   ` Viresh Kumar
2021-08-31  5:31 ` Viresh Kumar
2021-08-31 14:25   ` Michael S. Tsirkin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=94c12705602929968477aaf27e02439eb7a7f253.1627362340.git.viresh.kumar@linaro.org \
    --to=viresh.kumar@linaro.org \
    --cc=alex.bennee@linaro.org \
    --cc=arnd@arndb.de \
    --cc=arnd@kernel.org \
    --cc=bill.mills@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=info@metux.net \
    --cc=jasowang@redhat.com \
    --cc=jean-philippe@linaro.org \
    --cc=jie.deng@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=robh+dt@kernel.org \
    --cc=vincent.guittot@linaro.org \
    --cc=virtualization@lists.linux-foundation.org \
    --subject='Re: [PATCH V4 5/5] virtio: Bind virtio device to device-tree node' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).