HID: introduce hid_is_using_ll_driver

Although HID itself is transport-agnostic, occasionally a driver may
want to interact with the low-level transport that a device is connected
through. To do this, we need to know what kind of bus is in use. The
first guess may be to look at the 'bus' field of the 'struct hid_device',
but this field may be emulated in some cases (e.g. uhid).

More ideally, we can check which ll_driver a device is using. This
function introduces a 'hid_is_using_ll_driver' function and makes the
'struct hid_ll_driver' of the four most common transports accessible
through hid.h.

Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Acked-By: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 046f692fd0a2675ceb98f800b3e73f76e8da286b..77396145d2d093af60e44c825ffaabd25f9b68a1 100644 (file)
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -780,7 +780,7 @@ static int i2c_hid_power(struct hid_device *hid, int lvl)
        return 0;
 }
 
-static struct hid_ll_driver i2c_hid_ll_driver = {
+struct hid_ll_driver i2c_hid_ll_driver = {
        .parse = i2c_hid_parse,
        .start = i2c_hid_start,
        .stop = i2c_hid_stop,
@@ -790,6 +790,7 @@ static struct hid_ll_driver i2c_hid_ll_driver = {
        .output_report = i2c_hid_output_report,
        .raw_request = i2c_hid_raw_request,
 };
+EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
 
 static int i2c_hid_init_irq(struct i2c_client *client)
 {

diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index 7f8ff39ed44bd7900f006956b001e57f93c22143..6f819f144cb4f063a4962a202dc8b472c921a235 100644 (file)
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -369,7 +369,7 @@ static int uhid_hid_output_report(struct hid_device *hid, __u8 *buf,
        return uhid_hid_output_raw(hid, buf, count, HID_OUTPUT_REPORT);
 }
 
-static struct hid_ll_driver uhid_hid_driver = {
+struct hid_ll_driver uhid_hid_driver = {
        .start = uhid_hid_start,
        .stop = uhid_hid_stop,
        .open = uhid_hid_open,
@@ -378,6 +378,7 @@ static struct hid_ll_driver uhid_hid_driver = {
        .raw_request = uhid_hid_raw_request,
        .output_report = uhid_hid_output_report,
 };
+EXPORT_SYMBOL_GPL(uhid_hid_driver);
 
 #ifdef CONFIG_COMPAT
 

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 76013eb5cb7faedbf5ec6ca62dca6181afc5919b..e1047ad0d59bee95af76a65e01e01b080c4f5059 100644 (file)
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1261,7 +1261,7 @@ static int usbhid_idle(struct hid_device *hid, int report, int idle,
        return hid_set_idle(dev, ifnum, report, idle);
 }
 
-static struct hid_ll_driver usb_hid_driver = {
+struct hid_ll_driver usb_hid_driver = {
        .parse = usbhid_parse,
        .start = usbhid_start,
        .stop = usbhid_stop,
@@ -1274,6 +1274,7 @@ static struct hid_ll_driver usb_hid_driver = {
        .output_report = usbhid_output_report,
        .idle = usbhid_idle,
 };
+EXPORT_SYMBOL_GPL(usb_hid_driver);
 
 static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {

diff --git a/include/linux/hid.h b/include/linux/hid.h
index 5006f9b5d83701a77529988644cd9b018485bf7b..3853408daf7f4f6d135e7f1d4a77a0770762e22b 100644 (file)
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -777,6 +777,17 @@ struct hid_ll_driver {
        int (*idle)(struct hid_device *hdev, int report, int idle, int reqtype);
 };
 
+extern struct hid_ll_driver i2c_hid_ll_driver;
+extern struct hid_ll_driver hidp_hid_driver;
+extern struct hid_ll_driver uhid_hid_driver;
+extern struct hid_ll_driver usb_hid_driver;
+
+static inline bool hid_is_using_ll_driver(struct hid_device *hdev,
+               struct hid_ll_driver *driver)
+{
+       return hdev->ll_driver == driver;
+}
+
 #define        PM_HINT_FULLON  1<<5
 #define PM_HINT_NORMAL 1<<1
 

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 002743ea509c2035f78212097bb00af2b0392d1c..8112893037bdc0afee1247dad7ac6433ac0168bb 100644 (file)
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -734,7 +734,7 @@ static void hidp_stop(struct hid_device *hid)
        hid->claimed = 0;
 }
 
-static struct hid_ll_driver hidp_hid_driver = {
+struct hid_ll_driver hidp_hid_driver = {
        .parse = hidp_parse,
        .start = hidp_start,
        .stop = hidp_stop,
@@ -743,6 +743,7 @@ static struct hid_ll_driver hidp_hid_driver = {
        .raw_request = hidp_raw_request,
        .output_report = hidp_output_report,
 };
+EXPORT_SYMBOL_GPL(hidp_hid_driver);
 
 /* This function sets up the hid device. It does not add it
    to the HID system. That is done in hidp_add_connection(). */