[PATCH v2 0/2] HID: hiddev: move hiddev's minor number and refactoring

[PATCH v2 0/2] HID: hiddev: move hiddev's minor number and refactoring

[Jaejoong Kim]

Hi all,

   I found hiddev's minor number is always zero in struct hid_device. So,
   store the minor number asked from usb core in struct hid_device.

   This is my first approach.

   But after reviewed from Bendjamin, he suggested that it would make sense
   to store a minor number in struct hiddev like hidraw if it neeeded.

   So, I move the minor number from hid_device to hiddev and do some refactoring
   to access struct hiddev in hid-core

Chanes in v2:
- cp2112: tie in this series

- hiddev: rollback struct hiddev_list exported
          squash this patch in a seperate patch

Jaejoong Kim (2):
  HID: cp2112: use proper hidraw name with minor number
  HID: hiddev: reallocate hiddev's minor number

 drivers/hid/hid-core.c      |  2 +-
 drivers/hid/hid-cp2112.c    |  4 +++-
 drivers/hid/usbhid/hiddev.c | 15 ++++-----------
 include/linux/hid.h         |  1 -
 include/linux/hiddev.h      | 11 +++++++++++
 5 files changed, 19 insertions(+), 14 deletions(-)

-- 
2.7.4

[PATCH v2 1/2] HID: cp2112: use proper hidraw name with minor number

[Jaejoong Kim]

The cp2112 driver is working on hidraw not hiddev. So we need to use proper
hidraw name with hidraw's minor number.

Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
---
Changes in v2:
- tie in a series
---

 drivers/hid/hid-cp2112.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index b22d0f8..078026f 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -27,6 +27,7 @@
 #include <linux/gpio.h>
 #include <linux/gpio/driver.h>
 #include <linux/hid.h>
+#include <linux/hidraw.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/nls.h>
@@ -1297,7 +1298,8 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	dev->adap.algo_data	= dev;
 	dev->adap.dev.parent	= &hdev->dev;
 	snprintf(dev->adap.name, sizeof(dev->adap.name),
-		 "CP2112 SMBus Bridge on hiddev%d", hdev->minor);
+		 "CP2112 SMBus Bridge on hidraw%d",
+		 ((struct hidraw *)hdev->hidraw)->minor);
 	dev->hwversion = buf[2];
 	init_waitqueue_head(&dev->wait);
 
-- 
2.7.4

[PATCH v2 2/2] HID: hiddev: reallocate hiddev's minor number

[Jaejoong Kim]

We need to store the minor number each drivers. In case of hidraw, the
minor number is stored stores in struct hidraw. But hiddev's minor is
located in struct hid_device.

The hid-core driver announces a kernel message which driver is loaded when
HID device connected, but hiddev's minor number is always zero. To proper
display hiddev's minor number, we need to store the minor number asked from
usb core and do some refactoring work (move from hiddev.c to hiddev.h) to
access hiddev in hid-core.

Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
---
Chanes in v2:
- rollback struct hiddev_list exported
- squash this patch in a seperate patch
---

 drivers/hid/hid-core.c      |  2 +-
 drivers/hid/usbhid/hiddev.c | 15 ++++-----------
 include/linux/hid.h         |  1 -
 include/linux/hiddev.h      | 11 +++++++++++
 4 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index e9e87d3..1a0b910 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1695,7 +1695,7 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
 		len += sprintf(buf + len, "input");
 	if (hdev->claimed & HID_CLAIMED_HIDDEV)
 		len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
-				hdev->minor);
+				((struct hiddev *)hdev->hiddev)->minor);
 	if (hdev->claimed & HID_CLAIMED_HIDRAW)
 		len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
 				((struct hidraw *)hdev->hidraw)->minor);
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 700145b..27721c3 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -44,17 +44,7 @@
 #define HIDDEV_MINOR_BASE	96
 #define HIDDEV_MINORS		16
 #endif
-#define HIDDEV_BUFFER_SIZE	2048
-
-struct hiddev {
-	int exist;
-	int open;
-	struct mutex existancelock;
-	wait_queue_head_t wait;
-	struct hid_device *hid;
-	struct list_head list;
-	spinlock_t list_lock;
-};
+#define HIDDEV_BUFFER_SIZE      2048
 
 struct hiddev_list {
 	struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
@@ -910,6 +900,9 @@ int hiddev_connect(struct hid_device *hid, unsigned int force)
 		kfree(hiddev);
 		return -1;
 	}
+
+	hiddev->minor = usbhid->intf->minor;
+
 	return 0;
 }
 
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 28f38e2b8..643c017 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -541,7 +541,6 @@ struct hid_device {							/* device report descriptor */
 	struct list_head inputs;					/* The list of inputs */
 	void *hiddev;							/* The hiddev structure */
 	void *hidraw;
-	int minor;							/* Hiddev minor number */
 
 	int open;							/* is the device open by anyone? */
 	char name[128];							/* Device name */
diff --git a/include/linux/hiddev.h b/include/linux/hiddev.h
index a5dd814..fb407da 100644
--- a/include/linux/hiddev.h
+++ b/include/linux/hiddev.h
@@ -32,6 +32,17 @@
  * In-kernel definitions.
  */
 
+struct hiddev {
+	int minor;
+	int exist;
+	int open;
+	struct mutex existancelock;
+	wait_queue_head_t wait;
+	struct hid_device *hid;
+	struct list_head list;
+	spinlock_t list_lock;
+};
+
 struct hid_device;
 struct hid_usage;
 struct hid_field;
-- 
2.7.4

Re: [PATCH v2 0/2] HID: hiddev: move hiddev's minor number and refactoring

[Jiri Kosina]

On Fri, 3 Mar 2017, Jaejoong Kim wrote:

> Jaejoong Kim (2):
>   HID: cp2112: use proper hidraw name with minor number
>   HID: hiddev: reallocate hiddev's minor number

Applied to for-4.12/hiddev. Thanks,

-- 
Jiri Kosina
SUSE Labs