caif-hsi: Making read and writes asynchronous.

Some platforms do not allow to put HSI block into low-power
mode when FIFO is not empty. The patch flushes (by reading)
FIFO at wake down sequence. Asynchronous read and write is
implemented for that. As a side effect this will also greatly
improve performance.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 9 deletions

diff --git a/include/net/caif/caif_hsi.h b/include/net/caif/caif_hsi.h
index c5dedd87b4cb..17dff451efe3 100644
--- a/include/net/caif/caif_hsi.h
+++ b/include/net/caif/caif_hsi.h
@@ -75,18 +75,21 @@ struct cfhsi_desc {
 #define CFHSI_WAKE_UP_ACK                       1
 #define CFHSI_WAKE_DOWN_ACK                     2
 #define CFHSI_AWAKE                             3
-#define CFHSI_PENDING_RX                        4
-#define CFHSI_SHUTDOWN                          6
-#define CFHSI_FLUSH_FIFO                        7
+#define CFHSI_WAKELOCK_HELD                     4
+#define CFHSI_SHUTDOWN                          5
+#define CFHSI_FLUSH_FIFO                        6
 
 #ifndef CFHSI_INACTIVITY_TOUT
 #define CFHSI_INACTIVITY_TOUT                   (1 * HZ)
 #endif /* CFHSI_INACTIVITY_TOUT */
 
-#ifndef CFHSI_WAKEUP_TOUT
-#define CFHSI_WAKEUP_TOUT                       (3 * HZ)
-#endif /* CFHSI_WAKEUP_TOUT */
+#ifndef CFHSI_WAKE_TOUT
+#define CFHSI_WAKE_TOUT                 (3 * HZ)
+#endif /* CFHSI_WAKE_TOUT */
 
+#ifndef CFHSI_MAX_RX_RETRIES
+#define CFHSI_MAX_RX_RETRIES            (10 * HZ)
+#endif
 
 /* Structure implemented by the CAIF HSI driver. */
 struct cfhsi_drv {
@@ -109,6 +112,15 @@ struct cfhsi_dev {
         struct cfhsi_drv *drv;
 };
 
+/* Structure holds status of received CAIF frames processing */
+struct cfhsi_rx_state {
+        int state;
+        int nfrms;
+        int pld_len;
+        int retries;
+        bool piggy_desc;
+};
+
 /* Structure implemented by CAIF HSI drivers. */
 struct cfhsi {
         struct caif_dev_common cfdev;
@@ -118,7 +130,7 @@ struct cfhsi {
         struct cfhsi_drv drv;
         struct cfhsi_dev *dev;
         int tx_state;
-        int rx_state;
+        struct cfhsi_rx_state rx_state;
         int rx_len;
         u8 *rx_ptr;
         u8 *tx_buf;
@@ -130,13 +142,12 @@ struct cfhsi {
         struct list_head list;
         struct work_struct wake_up_work;
         struct work_struct wake_down_work;
-        struct work_struct rx_done_work;
-        struct work_struct tx_done_work;
         struct workqueue_struct *wq;
         wait_queue_head_t wake_up_wait;
         wait_queue_head_t wake_down_wait;
         wait_queue_head_t flush_fifo_wait;
         struct timer_list timer;
+        struct timer_list rx_slowpath_timer;
         unsigned long bits;
 };