* Internal driver structures.
*/
+/*
+ * The only reason to have several buffers is to accomodate assumptions
+ * in line disciplines. They ask for empty space amount, receive our URB size,
+ * and proceed to issue several 1-character writes, assuming they will fit.
+ * The very first write takes a complete URB. Fortunately, this only happens
+ * when processing onlcr, so we only need 2 buffers.
+ */
+#define ACM_NWB 2
+#define ACM_NRU 16
+#define ACM_NRB 16
+
+struct acm_wb {
+ unsigned char *buf;
+ dma_addr_t dmah;
+ int len;
+ int use;
+};
+
+struct acm_rb {
+ struct list_head list;
+ int size;
+ unsigned char *base;
+ dma_addr_t dma;
+};
+
+struct acm_ru {
+ struct list_head list;
+ struct acm_rb *buffer;
+ struct urb *urb;
+ struct acm *instance;
+};
+
struct acm {
struct usb_device *dev; /* the corresponding usb device */
struct usb_interface *control; /* control interface */
struct usb_interface *data; /* data interface */
struct tty_struct *tty; /* the corresponding tty */
- struct urb *ctrlurb, *readurb, *writeurb; /* urbs */
- u8 *ctrl_buffer, *read_buffer, *write_buffer; /* buffers of urbs */
- dma_addr_t ctrl_dma, read_dma, write_dma; /* dma handles of buffers */
+ struct urb *ctrlurb, *writeurb; /* urbs */
+ u8 *ctrl_buffer; /* buffers of urbs */
+ dma_addr_t ctrl_dma; /* dma handles of buffers */
+ struct acm_wb wb[ACM_NWB];
+ struct acm_ru ru[ACM_NRU];
+ struct acm_rb rb[ACM_NRB];
+ int rx_endpoint;
+ spinlock_t read_lock;
+ struct list_head spare_read_urbs;
+ struct list_head spare_read_bufs;
+ struct list_head filled_read_bufs;
+ int write_current; /* current write buffer */
+ int write_used; /* number of non-empty write buffers */
+ int write_ready; /* write urb is not running */
+ spinlock_t write_lock;
struct usb_cdc_line_coding line; /* bits, stop, parity */
struct work_struct work; /* work queue entry for line discipline waking up */
- struct tasklet_struct bh; /* rx processing */
+ struct tasklet_struct urb_task; /* rx processing */
spinlock_t throttle_lock; /* synchronize throtteling and read callback */
unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */
unsigned int ctrlout; /* output control lines (DTR, RTS) */
unsigned int minor; /* acm minor number */
unsigned char throttle; /* throttled by tty layer */
unsigned char clocal; /* termios CLOCAL */
- unsigned char ready_for_write; /* write urb can be used */
- unsigned char resubmit_to_unthrottle; /* throtteling has disabled the read urb */
unsigned int ctrl_caps; /* control capabilities from the class specific header */
};