On Thu, 22 Dec 2011 02:21:18 +0100, Benoit Goby <benoit@xxxxxxxxxxx> wrote:
+struct mtp_dev {
+ struct usb_function function;
+ struct usb_composite_dev *cdev;
+ spinlock_t lock;
+
+ struct usb_ep *ep_in;
+ struct usb_ep *ep_out;
+ struct usb_ep *ep_intr;
+
+ int state;
+
+ /* synchronize access to our device file */
+ atomic_t open_excl;
+ /* to enforce only one ioctl at a time */
+ atomic_t ioctl_excl;
+
+ struct list_head tx_idle;
+ struct list_head intr_idle;
+
+ wait_queue_head_t read_wq;
+ wait_queue_head_t write_wq;
+ wait_queue_head_t intr_wq;
+ struct usb_request *rx_req[RX_REQ_MAX];
+ int rx_done;
+
+ /* for processing MTP_SEND_FILE, MTP_RECEIVE_FILE and
+ * MTP_SEND_FILE_WITH_HEADER ioctls on a work queue
+ */
Invalid comment style. This likely applies to other places as well.
+ struct workqueue_struct *wq;
+ struct work_struct send_file_work;
+ struct work_struct receive_file_work;
+ struct file *xfer_file;
+ loff_t xfer_file_offset;
+ int64_t xfer_file_length;
+ unsigned xfer_send_header;
+ uint16_t xfer_command;
+ uint32_t xfer_transaction_id;
+ int xfer_result;
+};
+/* Microsoft MTP OS String */
+static u8 mtp_os_string[] = {
+ 18, /* sizeof(mtp_os_string) */
+ USB_DT_STRING,
+ /* Signature field: "MSFT100" */
+ 'M', 0, 'S', 0, 'F', 0, 'T', 0, '1', 0, '0', 0, '0', 0,
Those zeroes are a bit confusing (at least for me). Could we replace zeros
by “'\0', ie.: 'M', '\0', ..., '1', '\0', '0', '\0', ...”, which I think is
more obvious.
+ /* vendor code */
+ 1,
+ /* padding */
+ 0
+};
+static inline int mtp_lock(atomic_t *excl)
+{
+ if (atomic_inc_return(excl) == 1) {
+ return 0;
+ } else {
+ atomic_dec(excl);
+ return -1;
+ }
+}
+
+static inline void mtp_unlock(atomic_t *excl)
+{
+ atomic_dec(excl);
+}
Why not xchg() or test_and_set_bit() and clear_bit(), ie.:
static inline int mpt_lock(unsigned *excl)
{
return xchg(1, excl) ? -1 : 0;
}
static inline void mtp_unlock(unsigned *excl)
{
*excl = 0;
}
--
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o
..o | Computer Science, Michał “mina86” Nazarewicz (o o)
ooo +----<email/xmpp: mpn@xxxxxxxxxx>--------------ooO--(_)--Ooo--
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