[PATCH v4 26/43] usb: gadget: f_hid: conversion to new API

From: Robert Baldyga
Date: Wed Feb 03 2016 - 07:48:31 EST


Generate descriptors in new format and attach them to USB function in
prep_descs(). Implement prep_vendor_descs() to supply class specific
descriptors. Change set_alt() implementation and implement clear_alt()
operation. Move cdev initialization to hidg_alloc(). Remove boilerplate
code.

Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
---
drivers/usb/gadget/function/f_hid.c | 305 ++++++++++++++----------------------
1 file changed, 119 insertions(+), 186 deletions(-)

diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index 0456a53..8770289 100644
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -125,14 +125,6 @@ static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
*/
};

-static struct usb_descriptor_header *hidg_hs_descriptors[] = {
- (struct usb_descriptor_header *)&hidg_interface_desc,
- (struct usb_descriptor_header *)&hidg_desc,
- (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
- (struct usb_descriptor_header *)&hidg_hs_out_ep_desc,
- NULL,
-};
-
/* Full-Speed Support */

static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
@@ -159,13 +151,16 @@ static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
*/
};

-static struct usb_descriptor_header *hidg_fs_descriptors[] = {
- (struct usb_descriptor_header *)&hidg_interface_desc,
- (struct usb_descriptor_header *)&hidg_desc,
- (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
- (struct usb_descriptor_header *)&hidg_fs_out_ep_desc,
- NULL,
-};
+USB_COMPOSITE_ENDPOINT(ep_in, &hidg_fs_in_ep_desc,
+ &hidg_hs_in_ep_desc, NULL, NULL);
+USB_COMPOSITE_ENDPOINT(ep_out, &hidg_fs_out_ep_desc,
+ &hidg_hs_out_ep_desc, NULL, NULL);
+
+USB_COMPOSITE_ALTSETTING(intf0alt0, &hidg_interface_desc, &ep_in, &ep_out);
+
+USB_COMPOSITE_INTERFACE(intf0, &intf0alt0);
+
+USB_COMPOSITE_DESCRIPTORS(hidg_descs, &intf0);

/*-------------------------------------------------------------------------*/
/* Strings */
@@ -487,27 +482,6 @@ respond:
return status;
}

-static void hidg_disable(struct usb_function *f)
-{
- struct f_hidg *hidg = func_to_hidg(f);
- struct f_hidg_req_list *list, *next;
- int i;
-
- usb_ep_disable(hidg->in_ep);
- usb_ep_disable(hidg->out_ep);
-
- list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
- list_del(&list->list);
- kfree(list);
- }
-
- for (i = 0; i < hidg->qlen; ++i) {
- kfree(hidg->out_reqs[i]->buf);
- kfree(hidg->out_reqs[i]);
- }
- kfree(hidg->out_reqs);
-}
-
static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct usb_composite_dev *cdev = f->config->cdev;
@@ -516,65 +490,46 @@ static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)

VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);

- if (hidg->in_ep != NULL) {
- /* restart endpoint */
- usb_ep_disable(hidg->in_ep);
+ hidg->in_ep = usb_function_get_ep(f, intf, 0);
+ if (!hidg->in_ep)
+ return -ENODEV;
+ hidg->in_ep->driver_data = hidg;

- status = config_ep_by_speed(f->config->cdev->gadget, f,
- hidg->in_ep);
- if (status) {
- ERROR(cdev, "config_ep_by_speed FAILED!\n");
- goto fail;
- }
- status = usb_ep_enable(hidg->in_ep);
- if (status < 0) {
- ERROR(cdev, "Enable IN endpoint FAILED!\n");
- goto fail;
- }
- hidg->in_ep->driver_data = hidg;
- }
+ hidg->out_ep = usb_function_get_ep(f, intf, 1);
+ if (!hidg->out_ep)
+ return -ENODEV;
+ hidg->out_ep->driver_data = hidg;

+ /* preallocate request and buffer */
+ hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
+ if (!hidg->req)
+ return -ENOMEM;

- if (hidg->out_ep != NULL) {
- /* restart endpoint */
- usb_ep_disable(hidg->out_ep);
+ hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
+ if (!hidg->req->buf)
+ return -ENOMEM;

- status = config_ep_by_speed(f->config->cdev->gadget, f,
- hidg->out_ep);
- if (status) {
- ERROR(cdev, "config_ep_by_speed FAILED!\n");
- goto fail;
- }
- status = usb_ep_enable(hidg->out_ep);
- if (status < 0) {
- ERROR(cdev, "Enable IN endpoint FAILED!\n");
- goto fail;
- }
- hidg->out_ep->driver_data = hidg;
-
- /*
- * allocate a bunch of read buffers and queue them all at once.
- */
- hidg->out_reqs = kzalloc(hidg->qlen *
- sizeof(*hidg->out_reqs), GFP_KERNEL);
- for (i = 0; i < hidg->qlen && status == 0; i++) {
- struct usb_request *req =
- hidg_alloc_ep_req(hidg->out_ep,
- hidg->report_length);
- if (req) {
+ /*
+ * allocate a bunch of read buffers and queue them all at once.
+ */
+ hidg->out_reqs = kzalloc(hidg->qlen *
+ sizeof(*hidg->out_reqs), GFP_KERNEL);
+ for (i = 0; i < hidg->qlen && status == 0; i++) {
+ struct usb_request *req =
+ hidg_alloc_ep_req(hidg->out_ep,
+ hidg->report_length);
+ if (req) {
hidg->out_reqs[i] = req;
- req->complete = hidg_set_report_complete;
- req->context = hidg;
- status = usb_ep_queue(hidg->out_ep, req,
- GFP_ATOMIC);
- if (status)
- ERROR(cdev, "%s queue req --> %d\n",
+ req->complete = hidg_set_report_complete;
+ req->context = hidg;
+ status = usb_ep_queue(hidg->out_ep, req,
+ GFP_ATOMIC);
+ if (status)
+ ERROR(cdev, "%s queue req --> %d\n",
hidg->out_ep->name, status);
- } else {
- usb_ep_disable(hidg->out_ep);
- status = -ENOMEM;
- goto free_req;
- }
+ } else {
+ status = -ENOMEM;
+ goto free_req;
}
}

@@ -587,10 +542,31 @@ free_req:
kfree(hidg->out_reqs);
}

-fail:
return status;
}

+static void hidg_clear_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+ struct f_hidg *hidg = func_to_hidg(f);
+ struct f_hidg_req_list *list, *next;
+ int i;
+
+ list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
+ list_del(&list->list);
+ kfree(list);
+ }
+
+ for (i = 0; i < hidg->qlen; ++i) {
+ kfree(hidg->out_reqs[i]->buf);
+ kfree(hidg->out_reqs[i]);
+ }
+ kfree(hidg->out_reqs);
+
+ /* disable/free request and end point */
+ kfree(hidg->req->buf);
+ usb_ep_free_request(hidg->in_ep, hidg->req);
+}
+
static const struct file_operations f_hidg_fops = {
.owner = THIS_MODULE,
.open = f_hidg_open,
@@ -601,50 +577,19 @@ static const struct file_operations f_hidg_fops = {
.llseek = noop_llseek,
};

-static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
+static int hidg_prep_descs(struct usb_function *f)
{
- struct usb_ep *ep;
+ struct usb_composite_dev *cdev = f->config->cdev;
struct f_hidg *hidg = func_to_hidg(f);
struct usb_string *us;
- struct device *device;
- int status;
- dev_t dev;

/* maybe allocate device-global string IDs, and patch descriptors */
- us = usb_gstrings_attach(c->cdev, ct_func_strings,
+ us = usb_gstrings_attach(cdev, ct_func_strings,
ARRAY_SIZE(ct_func_string_defs));
if (IS_ERR(us))
return PTR_ERR(us);
hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id;

- /* allocate instance-specific interface IDs, and patch descriptors */
- status = usb_interface_id(c, f);
- if (status < 0)
- goto fail;
- hidg_interface_desc.bInterfaceNumber = status;
-
- /* allocate instance-specific endpoints */
- status = -ENODEV;
- ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
- if (!ep)
- goto fail;
- hidg->in_ep = ep;
-
- ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
- if (!ep)
- goto fail;
- hidg->out_ep = ep;
-
- /* preallocate request and buffer */
- status = -ENOMEM;
- hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
- if (!hidg->req)
- goto fail;
-
- hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
- if (!hidg->req->buf)
- goto fail;
-
/* set descriptor dynamic values */
hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
@@ -652,6 +597,14 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+
+ return usb_function_set_descs(f, &hidg_descs);
+}
+
+static int hidg_prep_vendor_descs(struct usb_function *f)
+{
+ struct f_hidg *hidg = func_to_hidg(f);
+
/*
* We can use hidg_desc struct here but we should not relay
* that its content won't change after returning from this function.
@@ -660,50 +613,10 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
hidg_desc.desc[0].wDescriptorLength =
cpu_to_le16(hidg->report_desc_length);

- hidg_hs_in_ep_desc.bEndpointAddress =
- hidg_fs_in_ep_desc.bEndpointAddress;
- hidg_hs_out_ep_desc.bEndpointAddress =
- hidg_fs_out_ep_desc.bEndpointAddress;
-
- status = usb_assign_descriptors(f, hidg_fs_descriptors,
- hidg_hs_descriptors, NULL);
- if (status)
- goto fail;
-
- mutex_init(&hidg->lock);
- spin_lock_init(&hidg->spinlock);
- init_waitqueue_head(&hidg->write_queue);
- init_waitqueue_head(&hidg->read_queue);
- INIT_LIST_HEAD(&hidg->completed_out_req);
-
- /* create char device */
- cdev_init(&hidg->cdev, &f_hidg_fops);
- dev = MKDEV(major, hidg->minor);
- status = cdev_add(&hidg->cdev, dev, 1);
- if (status)
- goto fail_free_descs;
-
- device = device_create(hidg_class, NULL, dev, NULL,
- "%s%d", "hidg", hidg->minor);
- if (IS_ERR(device)) {
- status = PTR_ERR(device);
- goto del;
- }
+ usb_altset_add_vendor_desc(f, 0, 0,
+ (struct usb_descriptor_header *)&hidg_desc);

return 0;
-del:
- cdev_del(&hidg->cdev);
-fail_free_descs:
- usb_free_all_descriptors(f);
-fail:
- ERROR(f->config->cdev, "hidg_bind FAILED\n");
- if (hidg->req != NULL) {
- kfree(hidg->req->buf);
- if (hidg->in_ep != NULL)
- usb_ep_free_request(hidg->in_ep, hidg->req);
- }
-
- return status;
}

static inline int hidg_get_minor(void)
@@ -914,6 +827,10 @@ static void hidg_free(struct usb_function *f)

hidg = func_to_hidg(f);
opts = container_of(f->fi, struct f_hid_opts, func_inst);
+
+ device_destroy(hidg_class, MKDEV(major, hidg->minor));
+ cdev_del(&hidg->cdev);
+
kfree(hidg->report_desc);
kfree(hidg);
mutex_lock(&opts->lock);
@@ -921,31 +838,25 @@ static void hidg_free(struct usb_function *f)
mutex_unlock(&opts->lock);
}

-static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
-{
- struct f_hidg *hidg = func_to_hidg(f);
-
- device_destroy(hidg_class, MKDEV(major, hidg->minor));
- cdev_del(&hidg->cdev);
-
- /* disable/free request and end point */
- usb_ep_disable(hidg->in_ep);
- kfree(hidg->req->buf);
- usb_ep_free_request(hidg->in_ep, hidg->req);
-
- usb_free_all_descriptors(f);
-}
-
static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
{
struct f_hidg *hidg;
struct f_hid_opts *opts;
+ struct device *device;
+ dev_t dev;
+ int ret;

/* allocate and initialize one new instance */
hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
if (!hidg)
return ERR_PTR(-ENOMEM);

+ mutex_init(&hidg->lock);
+ spin_lock_init(&hidg->spinlock);
+ init_waitqueue_head(&hidg->write_queue);
+ init_waitqueue_head(&hidg->read_queue);
+ INIT_LIST_HEAD(&hidg->completed_out_req);
+
opts = container_of(fi, struct f_hid_opts, func_inst);

mutex_lock(&opts->lock);
@@ -961,26 +872,48 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
opts->report_desc_length,
GFP_KERNEL);
if (!hidg->report_desc) {
- kfree(hidg);
mutex_unlock(&opts->lock);
- return ERR_PTR(-ENOMEM);
+ ret = -ENOMEM;
+ goto err_hidg;
}
}

mutex_unlock(&opts->lock);

hidg->func.name = "hid";
- hidg->func.bind = hidg_bind;
- hidg->func.unbind = hidg_unbind;
+ hidg->func.prep_descs = hidg_prep_descs;
+ hidg->func.prep_vendor_descs = hidg_prep_vendor_descs;
hidg->func.set_alt = hidg_set_alt;
- hidg->func.disable = hidg_disable;
+ hidg->func.clear_alt = hidg_clear_alt;
hidg->func.setup = hidg_setup;
hidg->func.free_func = hidg_free;

/* this could me made configurable at some point */
hidg->qlen = 4;

+ /* create char device */
+ cdev_init(&hidg->cdev, &f_hidg_fops);
+ dev = MKDEV(major, hidg->minor);
+ ret = cdev_add(&hidg->cdev, dev, 1);
+ if (ret < 0)
+ goto err_report;
+
+ device = device_create(hidg_class, NULL, dev, NULL,
+ "%s%d", "hidg", hidg->minor);
+ if (IS_ERR(device)) {
+ ret = PTR_ERR(device);
+ goto err_cdev;
+ }
+
return &hidg->func;
+
+err_cdev:
+ cdev_del(&hidg->cdev);
+err_report:
+ kfree(hidg->report_desc);
+err_hidg:
+ kfree(hidg);
+ return ERR_PTR(ret);
}

DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
--
1.9.1