[PATCH v2] HID: autoload hid-multitouch as needed
From: benjamin.tissoires <hidden>
Date: 2012-03-27 16:12:25
From: Benjamin Tissoires <redacted> When the generic hid parsing of the report descriptors in hid-core detects that the device contains the field ContactID, the device should be handled by hid-multitouch, and hid-core should release it. This patch implements a temporary fix for hid-core to automatically call the loading of hid-multitouch. A better solution would involve userspace. The code is inspired from what is done in the bttv module. Signed-off-by: Benjamin Tissoires <redacted> --- Hi guys, I finally managed to find some time to resend this patch. Cheers, Benjamin drivers/hid/hid-core.c | 33 ++++++++++++++++++++++++++++++++- include/linux/hid.h | 8 ++++++++ 2 files changed, 40 insertions(+), 1 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 990fe19..a84221e 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c@@ -1210,6 +1210,31 @@ static struct bin_attribute dev_bin_attr_report_desc = { .size = HID_MAX_DESCRIPTOR_SIZE, }; +#if defined(CONFIG_MODULES) && defined(MODULE) +/* Loading of hid_multitouch. This is done from the kernel until we come up + * with a more robust solution. */ +static void hid_request_hid_mt_module_async(struct work_struct *work) +{ + request_module("hid-multitouch"); +} + +static void hid_request_hid_mt_module(struct hid_device *dev) +{ + dev->request_hid_mt_module = 1; + INIT_WORK(&dev->request_hid_mt_module_wk, + hid_request_hid_mt_module_async); + schedule_work(&dev->request_hid_mt_module_wk); +} + +static void hid_flush_request_modules(struct hid_device *dev) +{ + flush_work_sync(&dev->request_hid_mt_module_wk); +} +#else +#define hid_request_hid_mt_module(dev) +#define hid_flush_request_modules(dev) +#endif /* CONFIG_MODULES */ + int hid_connect(struct hid_device *hdev, unsigned int connect_mask) { static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
@@ -1235,7 +1260,9 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask) connect_mask & HID_CONNECT_HIDINPUT_FORCE)) hdev->claimed |= HID_CLAIMED_INPUT; if (hdev->quirks & HID_QUIRK_MULTITOUCH) { - /* this device should be handled by hid-multitouch, skip it */ + /* this device should be handled by hid-multitouch, request + * for hid-multitouch to be loaded and leave the device to it */ + hid_request_hid_mt_module(hdev); return -ENODEV; }
@@ -2107,6 +2134,8 @@ struct hid_device *hid_allocate_device(void) INIT_LIST_HEAD(&hdev->debug_list); sema_init(&hdev->driver_lock, 1); + hdev->request_hid_mt_module = 0; + return hdev; err: put_device(&hdev->dev);
@@ -2121,6 +2150,8 @@ static void hid_remove_device(struct hid_device *hdev) hid_debug_unregister(hdev); hdev->status &= ~HID_STAT_ADDED; } + if (hdev->request_hid_mt_module) + hid_flush_request_modules(hdev); } /**
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 3a95da6..0058ca9 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h@@ -538,6 +538,14 @@ struct hid_device { /* device report descriptor */ struct dentry *debug_events; struct list_head debug_list; wait_queue_head_t debug_wait; + + /* This is a temporary fix to make hid-multitouch loadable from + * the kernel before we come up with more robust solution + * (with userspace involvement). + * In case we detect a multitouch device through the parsing of + * hid-core, we request for hid-multitouch to be loaded. */ + struct work_struct request_hid_mt_module_wk; + bool request_hid_mt_module; }; static inline void *hid_get_drvdata(struct hid_device *hdev)
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1.7.7.6