lkml.org 
[lkml]   [2020]   [Mar]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/2] uio: add resource managed devm_uio_register_device() function
Date
This change adds a resource managed equivalent of uio_register_device().
Not adding devm_uio_unregister_device(), since the intent is to discourage
it's usage. Having such a function may allow some bad driver designs. Most
users of devm_*register*() functions rarely use the unregister equivalents.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---
drivers/uio/uio.c | 38 ++++++++++++++++++++++++++++++++++++++
include/linux/uio_driver.h | 9 +++++++++
2 files changed, 47 insertions(+)

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index a57698985f9c..6e725c6c6256 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -996,6 +996,44 @@ int __uio_register_device(struct module *owner,
}
EXPORT_SYMBOL_GPL(__uio_register_device);

+static void devm_uio_unregister_device(struct device *dev, void *res)
+{
+ uio_unregister_device(*(struct uio_info **)res);
+}
+
+/**
+ * devm_uio_register_device - Resource managed uio_register_device()
+ * @owner: module that creates the new device
+ * @parent: parent device
+ * @info: UIO device capabilities
+ *
+ * returns zero on success or a negative error code.
+ */
+int __devm_uio_register_device(struct module *owner,
+ struct device *parent,
+ struct uio_info *info)
+{
+ struct uio_info **ptr;
+ int ret;
+
+ ptr = devres_alloc(devm_uio_unregister_device, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ *ptr = info;
+ ret = __uio_register_device(owner, parent, info);
+ if (ret) {
+ devres_free(ptr);
+ return ret;
+ }
+
+ devres_add(parent, ptr);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__devm_uio_register_device);
+
/**
* uio_unregister_device - unregister a industrial IO device
* @info: UIO device capabilities
diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h
index 01081c4726c0..c5a306bd458c 100644
--- a/include/linux/uio_driver.h
+++ b/include/linux/uio_driver.h
@@ -123,6 +123,15 @@ extern int __must_check
extern void uio_unregister_device(struct uio_info *info);
extern void uio_event_notify(struct uio_info *info);

+extern int __must_check
+ __devm_uio_register_device(struct module *owner,
+ struct device *parent,
+ struct uio_info *info);
+
+/* use a define to avoid include chaining to get THIS_MODULE */
+#define devm_uio_register_device(parent, info) \
+ __devm_uio_register_device(THIS_MODULE, parent, info)
+
/* defines for uio_info->irq */
#define UIO_IRQ_CUSTOM -1
#define UIO_IRQ_NONE 0
--
2.20.1
\
 
 \ /
  Last update: 2020-03-06 17:16    [W:0.031 / U:5.576 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site