1 files changed, 27 insertions, 15 deletions

diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c
index c8bc69c97d1a..5ffdb364ea40 100644
--- a/drivers/char/synclink_gt.c
+++ b/drivers/char/synclink_gt.c
@@ -303,7 +303,7 @@ struct slgt_info {
         u32 idle_mode;
         u32 max_frame_size;       /* as set by device config */
 
-        unsigned int raw_rx_size;
+        unsigned int rbuf_fill_level;
         unsigned int if_mode;
 
         /* device status */
@@ -2676,8 +2676,29 @@ static int tx_abort(struct slgt_info *info)
 static int rx_enable(struct slgt_info *info, int enable)
 {
         unsigned long flags;
-        DBGINFO(("%s rx_enable(%d)\n", info->device_name, enable));
+        unsigned int rbuf_fill_level;
+        DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
         spin_lock_irqsave(&info->lock,flags);
+        /*
+         * enable[31..16] = receive DMA buffer fill level
+         * 0 = noop (leave fill level unchanged)
+         * fill level must be multiple of 4 and <= buffer size
+         */
+        rbuf_fill_level = ((unsigned int)enable) >> 16;
+        if (rbuf_fill_level) {
+                if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4))
+                        return -EINVAL;
+                info->rbuf_fill_level = rbuf_fill_level;
+                rx_stop(info); /* restart receiver to use new fill level */
+        }
+
+        /*
+         * enable[1..0] = receiver enable command
+         * 0 = disable
+         * 1 = enable
+         * 2 = enable or force hunt mode if already enabled
+         */
+        enable &= 3;
         if (enable) {
                 if (!info->rx_enabled)
                         rx_start(info);
@@ -3444,7 +3465,7 @@ static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev
                 info->magic = MGSL_MAGIC;
                 INIT_WORK(&info->task, bh_handler);
                 info->max_frame_size = 4096;
-                info->raw_rx_size = DMABUFSIZE;
+                info->rbuf_fill_level = DMABUFSIZE;
                 info->port.close_delay = 5*HZ/10;
                 info->port.closing_wait = 30*HZ;
                 init_waitqueue_head(&info->status_event_wait_q);
@@ -4447,16 +4468,7 @@ static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last
         while(!done) {
                 /* reset current buffer for reuse */
                 info->rbufs[i].status = 0;
-                switch(info->params.mode) {
-                case MGSL_MODE_RAW:
-                case MGSL_MODE_MONOSYNC:
-                case MGSL_MODE_BISYNC:
-                        set_desc_count(info->rbufs[i], info->raw_rx_size);
-                        break;
-                default:
-                        set_desc_count(info->rbufs[i], DMABUFSIZE);
-                }
-
+                set_desc_count(info->rbufs[i], info->rbuf_fill_level);
                 if (i == last)
                         done = 1;
                 if (++i == info->rbuf_count)
@@ -4563,7 +4575,7 @@ check_again:
 
         DBGBH(("%s rx frame status=%04X size=%d\n",
                 info->device_name, status, framesize));
-        DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, DMABUFSIZE), "rx");
+        DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
 
         if (framesize) {
                 if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
@@ -4583,7 +4595,7 @@ check_again:
                         info->icount.rxok++;
 
                         while(copy_count) {
-                                int partial_count = min(copy_count, DMABUFSIZE);
+                                int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
                                 memcpy(p, info->rbufs[i].buf, partial_count);
                                 p += partial_count;
                                 copy_count -= partial_count;