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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/gadget/function/f_hid.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/gadget/function/f_hid.c')
-rw-r--r--drivers/usb/gadget/function/f_hid.c1357
1 files changed, 1357 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
new file mode 100644
index 000000000..f1ca9250c
--- /dev/null
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -0,0 +1,1357 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * f_hid.c -- USB HID function driver
+ *
+ * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/hid.h>
+#include <linux/idr.h>
+#include <linux/cdev.h>
+#include <linux/mutex.h>
+#include <linux/poll.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/usb/g_hid.h>
+
+#include "u_f.h"
+#include "u_hid.h"
+
+#define HIDG_MINORS 4
+
+static int major, minors;
+static struct class *hidg_class;
+static DEFINE_IDA(hidg_ida);
+static DEFINE_MUTEX(hidg_ida_lock); /* protects access to hidg_ida */
+
+/*-------------------------------------------------------------------------*/
+/* HID gadget struct */
+
+struct f_hidg_req_list {
+ struct usb_request *req;
+ unsigned int pos;
+ struct list_head list;
+};
+
+struct f_hidg {
+ /* configuration */
+ unsigned char bInterfaceSubClass;
+ unsigned char bInterfaceProtocol;
+ unsigned char protocol;
+ unsigned char idle;
+ unsigned short report_desc_length;
+ char *report_desc;
+ unsigned short report_length;
+ /*
+ * use_out_ep - if true, the OUT Endpoint (interrupt out method)
+ * will be used to receive reports from the host
+ * using functions with the "intout" suffix.
+ * Otherwise, the OUT Endpoint will not be configured
+ * and the SETUP/SET_REPORT method ("ssreport" suffix)
+ * will be used to receive reports.
+ */
+ bool use_out_ep;
+
+ /* recv report */
+ spinlock_t read_spinlock;
+ wait_queue_head_t read_queue;
+ /* recv report - interrupt out only (use_out_ep == 1) */
+ struct list_head completed_out_req;
+ unsigned int qlen;
+ /* recv report - setup set_report only (use_out_ep == 0) */
+ char *set_report_buf;
+ unsigned int set_report_length;
+
+ /* send report */
+ spinlock_t write_spinlock;
+ bool write_pending;
+ wait_queue_head_t write_queue;
+ struct usb_request *req;
+
+ struct device dev;
+ struct cdev cdev;
+ struct usb_function func;
+
+ struct usb_ep *in_ep;
+ struct usb_ep *out_ep;
+};
+
+static inline struct f_hidg *func_to_hidg(struct usb_function *f)
+{
+ return container_of(f, struct f_hidg, func);
+}
+
+static void hidg_release(struct device *dev)
+{
+ struct f_hidg *hidg = container_of(dev, struct f_hidg, dev);
+
+ kfree(hidg->report_desc);
+ kfree(hidg->set_report_buf);
+ kfree(hidg);
+}
+
+/*-------------------------------------------------------------------------*/
+/* Static descriptors */
+
+static struct usb_interface_descriptor hidg_interface_desc = {
+ .bLength = sizeof hidg_interface_desc,
+ .bDescriptorType = USB_DT_INTERFACE,
+ /* .bInterfaceNumber = DYNAMIC */
+ .bAlternateSetting = 0,
+ /* .bNumEndpoints = DYNAMIC (depends on use_out_ep) */
+ .bInterfaceClass = USB_CLASS_HID,
+ /* .bInterfaceSubClass = DYNAMIC */
+ /* .bInterfaceProtocol = DYNAMIC */
+ /* .iInterface = DYNAMIC */
+};
+
+static struct hid_descriptor hidg_desc = {
+ .bLength = sizeof hidg_desc,
+ .bDescriptorType = HID_DT_HID,
+ .bcdHID = cpu_to_le16(0x0101),
+ .bCountryCode = 0x00,
+ .bNumDescriptors = 0x1,
+ /*.desc[0].bDescriptorType = DYNAMIC */
+ /*.desc[0].wDescriptorLenght = DYNAMIC */
+};
+
+/* Super-Speed Support */
+
+static struct usb_endpoint_descriptor hidg_ss_in_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 4, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_ss_ep_comp_descriptor hidg_ss_in_comp_desc = {
+ .bLength = sizeof(hidg_ss_in_comp_desc),
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+
+ /* .bMaxBurst = 0, */
+ /* .bmAttributes = 0, */
+ /* .wBytesPerInterval = DYNAMIC */
+};
+
+static struct usb_endpoint_descriptor hidg_ss_out_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 4, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = {
+ .bLength = sizeof(hidg_ss_out_comp_desc),
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+
+ /* .bMaxBurst = 0, */
+ /* .bmAttributes = 0, */
+ /* .wBytesPerInterval = DYNAMIC */
+};
+
+static struct usb_descriptor_header *hidg_ss_descriptors_intout[] = {
+ (struct usb_descriptor_header *)&hidg_interface_desc,
+ (struct usb_descriptor_header *)&hidg_desc,
+ (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
+ (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
+ (struct usb_descriptor_header *)&hidg_ss_out_ep_desc,
+ (struct usb_descriptor_header *)&hidg_ss_out_comp_desc,
+ NULL,
+};
+
+static struct usb_descriptor_header *hidg_ss_descriptors_ssreport[] = {
+ (struct usb_descriptor_header *)&hidg_interface_desc,
+ (struct usb_descriptor_header *)&hidg_desc,
+ (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
+ (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
+ NULL,
+};
+
+/* High-Speed Support */
+
+static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 4, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 4, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_descriptor_header *hidg_hs_descriptors_intout[] = {
+ (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,
+};
+
+static struct usb_descriptor_header *hidg_hs_descriptors_ssreport[] = {
+ (struct usb_descriptor_header *)&hidg_interface_desc,
+ (struct usb_descriptor_header *)&hidg_desc,
+ (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
+ NULL,
+};
+
+/* Full-Speed Support */
+
+static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 10, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ /*.wMaxPacketSize = DYNAMIC */
+ .bInterval = 10, /* FIXME: Add this field in the
+ * HID gadget configuration?
+ * (struct hidg_func_descriptor)
+ */
+};
+
+static struct usb_descriptor_header *hidg_fs_descriptors_intout[] = {
+ (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,
+};
+
+static struct usb_descriptor_header *hidg_fs_descriptors_ssreport[] = {
+ (struct usb_descriptor_header *)&hidg_interface_desc,
+ (struct usb_descriptor_header *)&hidg_desc,
+ (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
+ NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+/* Strings */
+
+#define CT_FUNC_HID_IDX 0
+
+static struct usb_string ct_func_string_defs[] = {
+ [CT_FUNC_HID_IDX].s = "HID Interface",
+ {}, /* end of list */
+};
+
+static struct usb_gadget_strings ct_func_string_table = {
+ .language = 0x0409, /* en-US */
+ .strings = ct_func_string_defs,
+};
+
+static struct usb_gadget_strings *ct_func_strings[] = {
+ &ct_func_string_table,
+ NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+/* Char Device */
+
+static ssize_t f_hidg_intout_read(struct file *file, char __user *buffer,
+ size_t count, loff_t *ptr)
+{
+ struct f_hidg *hidg = file->private_data;
+ struct f_hidg_req_list *list;
+ struct usb_request *req;
+ unsigned long flags;
+ int ret;
+
+ if (!count)
+ return 0;
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+
+#define READ_COND_INTOUT (!list_empty(&hidg->completed_out_req))
+
+ /* wait for at least one buffer to complete */
+ while (!READ_COND_INTOUT) {
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ if (wait_event_interruptible(hidg->read_queue, READ_COND_INTOUT))
+ return -ERESTARTSYS;
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+ }
+
+ /* pick the first one */
+ list = list_first_entry(&hidg->completed_out_req,
+ struct f_hidg_req_list, list);
+
+ /*
+ * Remove this from list to protect it from beign free()
+ * while host disables our function
+ */
+ list_del(&list->list);
+
+ req = list->req;
+ count = min_t(unsigned int, count, req->actual - list->pos);
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+ /* copy to user outside spinlock */
+ count -= copy_to_user(buffer, req->buf + list->pos, count);
+ list->pos += count;
+
+ /*
+ * if this request is completely handled and transfered to
+ * userspace, remove its entry from the list and requeue it
+ * again. Otherwise, we will revisit it again upon the next
+ * call, taking into account its current read position.
+ */
+ if (list->pos == req->actual) {
+ kfree(list);
+
+ req->length = hidg->report_length;
+ ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL);
+ if (ret < 0) {
+ free_ep_req(hidg->out_ep, req);
+ return ret;
+ }
+ } else {
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+ list_add(&list->list, &hidg->completed_out_req);
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+ wake_up(&hidg->read_queue);
+ }
+
+ return count;
+}
+
+#define READ_COND_SSREPORT (hidg->set_report_buf != NULL)
+
+static ssize_t f_hidg_ssreport_read(struct file *file, char __user *buffer,
+ size_t count, loff_t *ptr)
+{
+ struct f_hidg *hidg = file->private_data;
+ char *tmp_buf = NULL;
+ unsigned long flags;
+
+ if (!count)
+ return 0;
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+
+ while (!READ_COND_SSREPORT) {
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ if (wait_event_interruptible(hidg->read_queue, READ_COND_SSREPORT))
+ return -ERESTARTSYS;
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+ }
+
+ count = min_t(unsigned int, count, hidg->set_report_length);
+ tmp_buf = hidg->set_report_buf;
+ hidg->set_report_buf = NULL;
+
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+ if (tmp_buf != NULL) {
+ count -= copy_to_user(buffer, tmp_buf, count);
+ kfree(tmp_buf);
+ } else {
+ count = -ENOMEM;
+ }
+
+ wake_up(&hidg->read_queue);
+
+ return count;
+}
+
+static ssize_t f_hidg_read(struct file *file, char __user *buffer,
+ size_t count, loff_t *ptr)
+{
+ struct f_hidg *hidg = file->private_data;
+
+ if (hidg->use_out_ep)
+ return f_hidg_intout_read(file, buffer, count, ptr);
+ else
+ return f_hidg_ssreport_read(file, buffer, count, ptr);
+}
+
+static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
+ unsigned long flags;
+
+ if (req->status != 0) {
+ ERROR(hidg->func.config->cdev,
+ "End Point Request ERROR: %d\n", req->status);
+ }
+
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+ hidg->write_pending = 0;
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+ wake_up(&hidg->write_queue);
+}
+
+static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *offp)
+{
+ struct f_hidg *hidg = file->private_data;
+ struct usb_request *req;
+ unsigned long flags;
+ ssize_t status = -ENOMEM;
+
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+
+ if (!hidg->req) {
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+ return -ESHUTDOWN;
+ }
+
+#define WRITE_COND (!hidg->write_pending)
+try_again:
+ /* write queue */
+ while (!WRITE_COND) {
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ if (wait_event_interruptible_exclusive(
+ hidg->write_queue, WRITE_COND))
+ return -ERESTARTSYS;
+
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+ }
+
+ hidg->write_pending = 1;
+ req = hidg->req;
+ count = min_t(unsigned, count, hidg->report_length);
+
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+
+ if (!req) {
+ ERROR(hidg->func.config->cdev, "hidg->req is NULL\n");
+ status = -ESHUTDOWN;
+ goto release_write_pending;
+ }
+
+ status = copy_from_user(req->buf, buffer, count);
+ if (status != 0) {
+ ERROR(hidg->func.config->cdev,
+ "copy_from_user error\n");
+ status = -EINVAL;
+ goto release_write_pending;
+ }
+
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+
+ /* when our function has been disabled by host */
+ if (!hidg->req) {
+ free_ep_req(hidg->in_ep, req);
+ /*
+ * TODO
+ * Should we fail with error here?
+ */
+ goto try_again;
+ }
+
+ req->status = 0;
+ req->zero = 0;
+ req->length = count;
+ req->complete = f_hidg_req_complete;
+ req->context = hidg;
+
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+
+ if (!hidg->in_ep->enabled) {
+ ERROR(hidg->func.config->cdev, "in_ep is disabled\n");
+ status = -ESHUTDOWN;
+ goto release_write_pending;
+ }
+
+ status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC);
+ if (status < 0)
+ goto release_write_pending;
+ else
+ status = count;
+
+ return status;
+release_write_pending:
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+ hidg->write_pending = 0;
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+
+ wake_up(&hidg->write_queue);
+
+ return status;
+}
+
+static __poll_t f_hidg_poll(struct file *file, poll_table *wait)
+{
+ struct f_hidg *hidg = file->private_data;
+ __poll_t ret = 0;
+
+ poll_wait(file, &hidg->read_queue, wait);
+ poll_wait(file, &hidg->write_queue, wait);
+
+ if (WRITE_COND)
+ ret |= EPOLLOUT | EPOLLWRNORM;
+
+ if (hidg->use_out_ep) {
+ if (READ_COND_INTOUT)
+ ret |= EPOLLIN | EPOLLRDNORM;
+ } else {
+ if (READ_COND_SSREPORT)
+ ret |= EPOLLIN | EPOLLRDNORM;
+ }
+
+ return ret;
+}
+
+#undef WRITE_COND
+#undef READ_COND_SSREPORT
+#undef READ_COND_INTOUT
+
+static int f_hidg_release(struct inode *inode, struct file *fd)
+{
+ fd->private_data = NULL;
+ return 0;
+}
+
+static int f_hidg_open(struct inode *inode, struct file *fd)
+{
+ struct f_hidg *hidg =
+ container_of(inode->i_cdev, struct f_hidg, cdev);
+
+ fd->private_data = hidg;
+
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+/* usb_function */
+
+static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
+ unsigned length)
+{
+ return alloc_ep_req(ep, length);
+}
+
+static void hidg_intout_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_hidg *hidg = (struct f_hidg *) req->context;
+ struct usb_composite_dev *cdev = hidg->func.config->cdev;
+ struct f_hidg_req_list *req_list;
+ unsigned long flags;
+
+ switch (req->status) {
+ case 0:
+ req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC);
+ if (!req_list) {
+ ERROR(cdev, "Unable to allocate mem for req_list\n");
+ goto free_req;
+ }
+
+ req_list->req = req;
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+ list_add_tail(&req_list->list, &hidg->completed_out_req);
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+ wake_up(&hidg->read_queue);
+ break;
+ default:
+ ERROR(cdev, "Set report failed %d\n", req->status);
+ fallthrough;
+ case -ECONNABORTED: /* hardware forced ep reset */
+ case -ECONNRESET: /* request dequeued */
+ case -ESHUTDOWN: /* disconnect from host */
+free_req:
+ free_ep_req(ep, req);
+ return;
+ }
+}
+
+static void hidg_ssreport_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_hidg *hidg = (struct f_hidg *)req->context;
+ struct usb_composite_dev *cdev = hidg->func.config->cdev;
+ char *new_buf = NULL;
+ unsigned long flags;
+
+ if (req->status != 0 || req->buf == NULL || req->actual == 0) {
+ ERROR(cdev,
+ "%s FAILED: status=%d, buf=%p, actual=%d\n",
+ __func__, req->status, req->buf, req->actual);
+ return;
+ }
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+
+ new_buf = krealloc(hidg->set_report_buf, req->actual, GFP_ATOMIC);
+ if (new_buf == NULL) {
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+ return;
+ }
+ hidg->set_report_buf = new_buf;
+
+ hidg->set_report_length = req->actual;
+ memcpy(hidg->set_report_buf, req->buf, req->actual);
+
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+ wake_up(&hidg->read_queue);
+}
+
+static int hidg_setup(struct usb_function *f,
+ const struct usb_ctrlrequest *ctrl)
+{
+ struct f_hidg *hidg = func_to_hidg(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct usb_request *req = cdev->req;
+ int status = 0;
+ __u16 value, length;
+
+ value = __le16_to_cpu(ctrl->wValue);
+ length = __le16_to_cpu(ctrl->wLength);
+
+ VDBG(cdev,
+ "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n",
+ __func__, ctrl->bRequestType, ctrl->bRequest, value);
+
+ switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
+ case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_GET_REPORT):
+ VDBG(cdev, "get_report\n");
+
+ /* send an empty report */
+ length = min_t(unsigned, length, hidg->report_length);
+ memset(req->buf, 0x0, length);
+
+ goto respond;
+ break;
+
+ case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_GET_PROTOCOL):
+ VDBG(cdev, "get_protocol\n");
+ length = min_t(unsigned int, length, 1);
+ ((u8 *) req->buf)[0] = hidg->protocol;
+ goto respond;
+ break;
+
+ case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_GET_IDLE):
+ VDBG(cdev, "get_idle\n");
+ length = min_t(unsigned int, length, 1);
+ ((u8 *) req->buf)[0] = hidg->idle;
+ goto respond;
+ break;
+
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_SET_REPORT):
+ VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
+ if (hidg->use_out_ep)
+ goto stall;
+ req->complete = hidg_ssreport_complete;
+ req->context = hidg;
+ goto respond;
+ break;
+
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_SET_PROTOCOL):
+ VDBG(cdev, "set_protocol\n");
+ if (value > HID_REPORT_PROTOCOL)
+ goto stall;
+ length = 0;
+ /*
+ * We assume that programs implementing the Boot protocol
+ * are also compatible with the Report Protocol
+ */
+ if (hidg->bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
+ hidg->protocol = value;
+ goto respond;
+ }
+ goto stall;
+ break;
+
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+ | HID_REQ_SET_IDLE):
+ VDBG(cdev, "set_idle\n");
+ length = 0;
+ hidg->idle = value >> 8;
+ goto respond;
+ break;
+
+ case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
+ | USB_REQ_GET_DESCRIPTOR):
+ switch (value >> 8) {
+ case HID_DT_HID:
+ {
+ struct hid_descriptor hidg_desc_copy = hidg_desc;
+
+ VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
+ hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
+ hidg_desc_copy.desc[0].wDescriptorLength =
+ cpu_to_le16(hidg->report_desc_length);
+
+ length = min_t(unsigned short, length,
+ hidg_desc_copy.bLength);
+ memcpy(req->buf, &hidg_desc_copy, length);
+ goto respond;
+ break;
+ }
+ case HID_DT_REPORT:
+ VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
+ length = min_t(unsigned short, length,
+ hidg->report_desc_length);
+ memcpy(req->buf, hidg->report_desc, length);
+ goto respond;
+ break;
+
+ default:
+ VDBG(cdev, "Unknown descriptor request 0x%x\n",
+ value >> 8);
+ goto stall;
+ break;
+ }
+ break;
+
+ default:
+ VDBG(cdev, "Unknown request 0x%x\n",
+ ctrl->bRequest);
+ goto stall;
+ break;
+ }
+
+stall:
+ return -EOPNOTSUPP;
+
+respond:
+ req->zero = 0;
+ req->length = length;
+ status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+ if (status < 0)
+ ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
+ 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;
+ unsigned long flags;
+
+ usb_ep_disable(hidg->in_ep);
+
+ if (hidg->out_ep) {
+ usb_ep_disable(hidg->out_ep);
+
+ spin_lock_irqsave(&hidg->read_spinlock, flags);
+ list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
+ free_ep_req(hidg->out_ep, list->req);
+ list_del(&list->list);
+ kfree(list);
+ }
+ spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+ }
+
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+ if (!hidg->write_pending) {
+ free_ep_req(hidg->in_ep, hidg->req);
+ hidg->write_pending = 1;
+ }
+
+ hidg->req = NULL;
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+}
+
+static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct f_hidg *hidg = func_to_hidg(f);
+ struct usb_request *req_in = NULL;
+ unsigned long flags;
+ int i, status = 0;
+
+ 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);
+
+ 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;
+
+ req_in = hidg_alloc_ep_req(hidg->in_ep, hidg->report_length);
+ if (!req_in) {
+ status = -ENOMEM;
+ goto disable_ep_in;
+ }
+ }
+
+ if (hidg->use_out_ep && hidg->out_ep != NULL) {
+ /* restart endpoint */
+ usb_ep_disable(hidg->out_ep);
+
+ status = config_ep_by_speed(f->config->cdev->gadget, f,
+ hidg->out_ep);
+ if (status) {
+ ERROR(cdev, "config_ep_by_speed FAILED!\n");
+ goto free_req_in;
+ }
+ status = usb_ep_enable(hidg->out_ep);
+ if (status < 0) {
+ ERROR(cdev, "Enable OUT endpoint FAILED!\n");
+ goto free_req_in;
+ }
+ hidg->out_ep->driver_data = hidg;
+
+ /*
+ * allocate a bunch of read buffers and queue them all at once.
+ */
+ 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) {
+ req->complete = hidg_intout_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);
+ free_ep_req(hidg->out_ep, req);
+ }
+ } else {
+ status = -ENOMEM;
+ goto disable_out_ep;
+ }
+ }
+ }
+
+ if (hidg->in_ep != NULL) {
+ spin_lock_irqsave(&hidg->write_spinlock, flags);
+ hidg->req = req_in;
+ hidg->write_pending = 0;
+ spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+
+ wake_up(&hidg->write_queue);
+ }
+ return 0;
+disable_out_ep:
+ if (hidg->out_ep)
+ usb_ep_disable(hidg->out_ep);
+free_req_in:
+ if (req_in)
+ free_ep_req(hidg->in_ep, req_in);
+
+disable_ep_in:
+ if (hidg->in_ep)
+ usb_ep_disable(hidg->in_ep);
+
+fail:
+ return status;
+}
+
+static const struct file_operations f_hidg_fops = {
+ .owner = THIS_MODULE,
+ .open = f_hidg_open,
+ .release = f_hidg_release,
+ .write = f_hidg_write,
+ .read = f_hidg_read,
+ .poll = f_hidg_poll,
+ .llseek = noop_llseek,
+};
+
+static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_ep *ep;
+ struct f_hidg *hidg = func_to_hidg(f);
+ struct usb_string *us;
+ int status;
+
+ /* maybe allocate device-global string IDs, and patch descriptors */
+ us = usb_gstrings_attach(c->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;
+
+ hidg->out_ep = NULL;
+ if (hidg->use_out_ep) {
+ ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
+ if (!ep)
+ goto fail;
+ hidg->out_ep = ep;
+ }
+
+ /* used only if use_out_ep == 1 */
+ hidg->set_report_buf = NULL;
+
+ /* set descriptor dynamic values */
+ hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
+ hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
+ hidg_interface_desc.bNumEndpoints = hidg->use_out_ep ? 2 : 1;
+ hidg->protocol = HID_REPORT_PROTOCOL;
+ hidg->idle = 1;
+ hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ hidg_ss_in_comp_desc.wBytesPerInterval =
+ cpu_to_le16(hidg->report_length);
+ hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ hidg_ss_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ hidg_ss_out_comp_desc.wBytesPerInterval =
+ 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);
+ /*
+ * We can use hidg_desc struct here but we should not relay
+ * that its content won't change after returning from this function.
+ */
+ hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
+ 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;
+
+ hidg_ss_in_ep_desc.bEndpointAddress =
+ hidg_fs_in_ep_desc.bEndpointAddress;
+ hidg_ss_out_ep_desc.bEndpointAddress =
+ hidg_fs_out_ep_desc.bEndpointAddress;
+
+ if (hidg->use_out_ep)
+ status = usb_assign_descriptors(f,
+ hidg_fs_descriptors_intout,
+ hidg_hs_descriptors_intout,
+ hidg_ss_descriptors_intout,
+ hidg_ss_descriptors_intout);
+ else
+ status = usb_assign_descriptors(f,
+ hidg_fs_descriptors_ssreport,
+ hidg_hs_descriptors_ssreport,
+ hidg_ss_descriptors_ssreport,
+ hidg_ss_descriptors_ssreport);
+
+ if (status)
+ goto fail;
+
+ spin_lock_init(&hidg->write_spinlock);
+ hidg->write_pending = 1;
+ hidg->req = NULL;
+ spin_lock_init(&hidg->read_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);
+ status = cdev_device_add(&hidg->cdev, &hidg->dev);
+ if (status)
+ goto fail_free_descs;
+
+ return 0;
+fail_free_descs:
+ usb_free_all_descriptors(f);
+fail:
+ ERROR(f->config->cdev, "hidg_bind FAILED\n");
+ if (hidg->req != NULL)
+ free_ep_req(hidg->in_ep, hidg->req);
+
+ return status;
+}
+
+static inline int hidg_get_minor(void)
+{
+ int ret;
+
+ ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
+ if (ret >= HIDG_MINORS) {
+ ida_simple_remove(&hidg_ida, ret);
+ ret = -ENODEV;
+ }
+
+ return ret;
+}
+
+static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_hid_opts,
+ func_inst.group);
+}
+
+static void hid_attr_release(struct config_item *item)
+{
+ struct f_hid_opts *opts = to_f_hid_opts(item);
+
+ usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations hidg_item_ops = {
+ .release = hid_attr_release,
+};
+
+#define F_HID_OPT(name, prec, limit) \
+static ssize_t f_hid_opts_##name##_show(struct config_item *item, char *page)\
+{ \
+ struct f_hid_opts *opts = to_f_hid_opts(item); \
+ int result; \
+ \
+ mutex_lock(&opts->lock); \
+ result = sprintf(page, "%d\n", opts->name); \
+ mutex_unlock(&opts->lock); \
+ \
+ return result; \
+} \
+ \
+static ssize_t f_hid_opts_##name##_store(struct config_item *item, \
+ const char *page, size_t len) \
+{ \
+ struct f_hid_opts *opts = to_f_hid_opts(item); \
+ int ret; \
+ u##prec num; \
+ \
+ mutex_lock(&opts->lock); \
+ if (opts->refcnt) { \
+ ret = -EBUSY; \
+ goto end; \
+ } \
+ \
+ ret = kstrtou##prec(page, 0, &num); \
+ if (ret) \
+ goto end; \
+ \
+ if (num > limit) { \
+ ret = -EINVAL; \
+ goto end; \
+ } \
+ opts->name = num; \
+ ret = len; \
+ \
+end: \
+ mutex_unlock(&opts->lock); \
+ return ret; \
+} \
+ \
+CONFIGFS_ATTR(f_hid_opts_, name)
+
+F_HID_OPT(subclass, 8, 255);
+F_HID_OPT(protocol, 8, 255);
+F_HID_OPT(no_out_endpoint, 8, 1);
+F_HID_OPT(report_length, 16, 65535);
+
+static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page)
+{
+ struct f_hid_opts *opts = to_f_hid_opts(item);
+ int result;
+
+ mutex_lock(&opts->lock);
+ result = opts->report_desc_length;
+ memcpy(page, opts->report_desc, opts->report_desc_length);
+ mutex_unlock(&opts->lock);
+
+ return result;
+}
+
+static ssize_t f_hid_opts_report_desc_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct f_hid_opts *opts = to_f_hid_opts(item);
+ int ret = -EBUSY;
+ char *d;
+
+ mutex_lock(&opts->lock);
+
+ if (opts->refcnt)
+ goto end;
+ if (len > PAGE_SIZE) {
+ ret = -ENOSPC;
+ goto end;
+ }
+ d = kmemdup(page, len, GFP_KERNEL);
+ if (!d) {
+ ret = -ENOMEM;
+ goto end;
+ }
+ kfree(opts->report_desc);
+ opts->report_desc = d;
+ opts->report_desc_length = len;
+ opts->report_desc_alloc = true;
+ ret = len;
+end:
+ mutex_unlock(&opts->lock);
+ return ret;
+}
+
+CONFIGFS_ATTR(f_hid_opts_, report_desc);
+
+static ssize_t f_hid_opts_dev_show(struct config_item *item, char *page)
+{
+ struct f_hid_opts *opts = to_f_hid_opts(item);
+
+ return sprintf(page, "%d:%d\n", major, opts->minor);
+}
+
+CONFIGFS_ATTR_RO(f_hid_opts_, dev);
+
+static struct configfs_attribute *hid_attrs[] = {
+ &f_hid_opts_attr_subclass,
+ &f_hid_opts_attr_protocol,
+ &f_hid_opts_attr_no_out_endpoint,
+ &f_hid_opts_attr_report_length,
+ &f_hid_opts_attr_report_desc,
+ &f_hid_opts_attr_dev,
+ NULL,
+};
+
+static const struct config_item_type hid_func_type = {
+ .ct_item_ops = &hidg_item_ops,
+ .ct_attrs = hid_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static inline void hidg_put_minor(int minor)
+{
+ ida_simple_remove(&hidg_ida, minor);
+}
+
+static void hidg_free_inst(struct usb_function_instance *f)
+{
+ struct f_hid_opts *opts;
+
+ opts = container_of(f, struct f_hid_opts, func_inst);
+
+ mutex_lock(&hidg_ida_lock);
+
+ hidg_put_minor(opts->minor);
+ if (ida_is_empty(&hidg_ida))
+ ghid_cleanup();
+
+ mutex_unlock(&hidg_ida_lock);
+
+ if (opts->report_desc_alloc)
+ kfree(opts->report_desc);
+
+ kfree(opts);
+}
+
+static struct usb_function_instance *hidg_alloc_inst(void)
+{
+ struct f_hid_opts *opts;
+ struct usb_function_instance *ret;
+ int status = 0;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return ERR_PTR(-ENOMEM);
+ mutex_init(&opts->lock);
+ opts->func_inst.free_func_inst = hidg_free_inst;
+ ret = &opts->func_inst;
+
+ mutex_lock(&hidg_ida_lock);
+
+ if (ida_is_empty(&hidg_ida)) {
+ status = ghid_setup(NULL, HIDG_MINORS);
+ if (status) {
+ ret = ERR_PTR(status);
+ kfree(opts);
+ goto unlock;
+ }
+ }
+
+ opts->minor = hidg_get_minor();
+ if (opts->minor < 0) {
+ ret = ERR_PTR(opts->minor);
+ kfree(opts);
+ if (ida_is_empty(&hidg_ida))
+ ghid_cleanup();
+ goto unlock;
+ }
+ config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type);
+
+unlock:
+ mutex_unlock(&hidg_ida_lock);
+ return ret;
+}
+
+static void hidg_free(struct usb_function *f)
+{
+ struct f_hidg *hidg;
+ struct f_hid_opts *opts;
+
+ hidg = func_to_hidg(f);
+ opts = container_of(f->fi, struct f_hid_opts, func_inst);
+ put_device(&hidg->dev);
+ mutex_lock(&opts->lock);
+ --opts->refcnt;
+ mutex_unlock(&opts->lock);
+}
+
+static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct f_hidg *hidg = func_to_hidg(f);
+
+ cdev_device_del(&hidg->cdev, &hidg->dev);
+
+ 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;
+ int ret;
+
+ /* allocate and initialize one new instance */
+ hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
+ if (!hidg)
+ return ERR_PTR(-ENOMEM);
+
+ opts = container_of(fi, struct f_hid_opts, func_inst);
+
+ mutex_lock(&opts->lock);
+ ++opts->refcnt;
+
+ device_initialize(&hidg->dev);
+ hidg->dev.release = hidg_release;
+ hidg->dev.class = hidg_class;
+ hidg->dev.devt = MKDEV(major, opts->minor);
+ ret = dev_set_name(&hidg->dev, "hidg%d", opts->minor);
+ if (ret) {
+ --opts->refcnt;
+ mutex_unlock(&opts->lock);
+ return ERR_PTR(ret);
+ }
+
+ hidg->bInterfaceSubClass = opts->subclass;
+ hidg->bInterfaceProtocol = opts->protocol;
+ hidg->report_length = opts->report_length;
+ hidg->report_desc_length = opts->report_desc_length;
+ if (opts->report_desc) {
+ hidg->report_desc = kmemdup(opts->report_desc,
+ opts->report_desc_length,
+ GFP_KERNEL);
+ if (!hidg->report_desc) {
+ put_device(&hidg->dev);
+ --opts->refcnt;
+ mutex_unlock(&opts->lock);
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+ hidg->use_out_ep = !opts->no_out_endpoint;
+
+ mutex_unlock(&opts->lock);
+
+ hidg->func.name = "hid";
+ hidg->func.bind = hidg_bind;
+ hidg->func.unbind = hidg_unbind;
+ hidg->func.set_alt = hidg_set_alt;
+ hidg->func.disable = hidg_disable;
+ hidg->func.setup = hidg_setup;
+ hidg->func.free_func = hidg_free;
+
+ /* this could be made configurable at some point */
+ hidg->qlen = 4;
+
+ return &hidg->func;
+}
+
+DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Fabien Chouteau");
+
+int ghid_setup(struct usb_gadget *g, int count)
+{
+ int status;
+ dev_t dev;
+
+ hidg_class = class_create(THIS_MODULE, "hidg");
+ if (IS_ERR(hidg_class)) {
+ status = PTR_ERR(hidg_class);
+ hidg_class = NULL;
+ return status;
+ }
+
+ status = alloc_chrdev_region(&dev, 0, count, "hidg");
+ if (status) {
+ class_destroy(hidg_class);
+ hidg_class = NULL;
+ return status;
+ }
+
+ major = MAJOR(dev);
+ minors = count;
+
+ return 0;
+}
+
+void ghid_cleanup(void)
+{
+ if (major) {
+ unregister_chrdev_region(MKDEV(major, 0), minors);
+ major = minors = 0;
+ }
+
+ class_destroy(hidg_class);
+ hidg_class = NULL;
+}