[media] saa7164: buffer crc checks and ensure we use the memcpy func

Buffer crc checks and ensure we use the correct PCIe IO memcpy func

Signed-off-by: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

5 files changed, 191 insertions, 40 deletions

diff --git a/drivers/media/video/saa7164/saa7164-buffer.c b/drivers/media/video/saa7164/saa7164-buffer.c
index 0760891d5fa8..b75157d411dd 100644
--- a/drivers/media/video/saa7164/saa7164-buffer.c
+++ b/drivers/media/video/saa7164/saa7164-buffer.c
@@ -113,6 +113,7 @@ struct saa7164_buffer *saa7164_buffer_alloc(struct saa7164_port *port,
         buf->flags = SAA7164_BUFFER_FREE;
         buf->pos = 0;
         buf->actual_size = params->pitch * params->numberoflines;
+        buf->crc = 0;
         /* TODO: arg len is being ignored */
         buf->pci_size = SAA7164_PT_ENTRIES * 0x1000;
         buf->pt_size = (SAA7164_PT_ENTRIES * sizeof(u64)) + 0x1000;
@@ -129,8 +130,9 @@ struct saa7164_buffer *saa7164_buffer_alloc(struct saa7164_port *port,
                 goto fail2;
 
         /* init the buffers to a known pattern, easier during debugging */
-        memset(buf->cpu, 0xff, buf->pci_size);
-        memset(buf->pt_cpu, 0xff, buf->pt_size);
+        memset_io(buf->cpu, 0xff, buf->pci_size);
+        buf->crc = crc32(0, buf->cpu, buf->actual_size);
+        memset_io(buf->pt_cpu, 0xff, buf->pt_size);
 
         dprintk(DBGLVL_BUF, "%s()   allocated buffer @ 0x%p\n",
                 __func__, buf);
@@ -296,6 +298,7 @@ struct saa7164_user_buffer *saa7164_buffer_alloc_user(struct saa7164_dev *dev, u
 
         buf->actual_size = len;
         buf->pos = 0;
+        buf->crc = 0;
 
         dprintk(DBGLVL_BUF, "%s()   allocated user buffer @ 0x%p\n",
                 __func__, buf);
diff --git a/drivers/media/video/saa7164/saa7164-bus.c b/drivers/media/video/saa7164/saa7164-bus.c
index 49414c814859..ccc61007f33a 100644
--- a/drivers/media/video/saa7164/saa7164-bus.c
+++ b/drivers/media/video/saa7164/saa7164-bus.c
@@ -217,28 +217,28 @@ int saa7164_bus_set(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf)
                         dprintk(DBGLVL_BUS, "%s() tr4\n", __func__);
 
                         /* Split the msg into pieces as the ring wraps */
-                        memcpy(bus->m_pdwSetRing + curr_swp, msg, space_rem);
-                        memcpy(bus->m_pdwSetRing, (u8 *)msg + space_rem,
+                        memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, space_rem);
+                        memcpy_toio(bus->m_pdwSetRing, (u8 *)msg + space_rem,
                                 sizeof(*msg) - space_rem);
 
-                        memcpy(bus->m_pdwSetRing + sizeof(*msg) - space_rem,
+                        memcpy_toio(bus->m_pdwSetRing + sizeof(*msg) - space_rem,
                                 buf, msg->size);
 
                 } else if (space_rem == sizeof(*msg)) {
                         dprintk(DBGLVL_BUS, "%s() tr5\n", __func__);
 
                         /* Additional data at the beginning of the ring */
-                        memcpy(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
-                        memcpy(bus->m_pdwSetRing, buf, msg->size);
+                        memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
+                        memcpy_toio(bus->m_pdwSetRing, buf, msg->size);
 
                 } else {
                         /* Additional data wraps around the ring */
-                        memcpy(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
+                        memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
                         if (msg->size > 0) {
-                                memcpy(bus->m_pdwSetRing + curr_swp +
+                                memcpy_toio(bus->m_pdwSetRing + curr_swp +
                                         sizeof(*msg), buf, space_rem -
                                         sizeof(*msg));
-                                memcpy(bus->m_pdwSetRing, (u8 *)buf +
+                                memcpy_toio(bus->m_pdwSetRing, (u8 *)buf +
                                         space_rem - sizeof(*msg),
                                         bytes_to_write - space_rem);
                         }
@@ -250,8 +250,8 @@ int saa7164_bus_set(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf)
                 dprintk(DBGLVL_BUS, "%s() tr6\n", __func__);
 
                 /* The ring buffer doesn't wrap, two simple copies */
-                memcpy(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
-                memcpy(bus->m_pdwSetRing + curr_swp + sizeof(*msg), buf,
+                memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg));
+                memcpy_toio(bus->m_pdwSetRing + curr_swp + sizeof(*msg), buf,
                         msg->size);
         }
 
@@ -343,19 +343,19 @@ int saa7164_bus_get(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf,
                 new_grp -= bus->m_dwSizeGetRing;
                 space_rem = bus->m_dwSizeGetRing - curr_grp;
 
-                memcpy(&msg_tmp, bus->m_pdwGetRing + curr_grp, space_rem);
-                memcpy((u8 *)&msg_tmp + space_rem, bus->m_pdwGetRing,
+                memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, space_rem);
+                memcpy_fromio((u8 *)&msg_tmp + space_rem, bus->m_pdwGetRing,
                         bytes_to_read - space_rem);
 
         } else {
                 /* No wrapping */
-                memcpy(&msg_tmp, bus->m_pdwGetRing + curr_grp, bytes_to_read);
+                memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, bytes_to_read);
         }
 
         /* No need to update the read positions, because this was a peek */
         /* If the caller specifically want to peek, return */
         if (peekonly) {
-                memcpy(msg, &msg_tmp, sizeof(*msg));
+                memcpy_fromio(msg, &msg_tmp, sizeof(*msg));
                 goto peekout;
         }
 
@@ -401,24 +401,24 @@ int saa7164_bus_get(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf,
 
                 if (space_rem < sizeof(*msg)) {
                         /* msg wraps around the ring */
-                        memcpy(msg, bus->m_pdwGetRing + curr_grp, space_rem);
-                        memcpy((u8 *)msg + space_rem, bus->m_pdwGetRing,
+                        memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, space_rem);
+                        memcpy_fromio((u8 *)msg + space_rem, bus->m_pdwGetRing,
                                 sizeof(*msg) - space_rem);
                         if (buf)
-                                memcpy(buf, bus->m_pdwGetRing + sizeof(*msg) -
+                                memcpy_fromio(buf, bus->m_pdwGetRing + sizeof(*msg) -
                                         space_rem, buf_size);
 
                 } else if (space_rem == sizeof(*msg)) {
-                        memcpy(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+                        memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
                         if (buf)
                                 memcpy(buf, bus->m_pdwGetRing, buf_size);
                 } else {
                         /* Additional data wraps around the ring */
-                        memcpy(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+                        memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
                         if (buf) {
-                                memcpy(buf, bus->m_pdwGetRing + curr_grp +
+                                memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp +
                                         sizeof(*msg), space_rem - sizeof(*msg));
-                                memcpy(buf + space_rem - sizeof(*msg),
+                                memcpy_fromio(buf + space_rem - sizeof(*msg),
                                         bus->m_pdwGetRing, bytes_to_read -
                                         space_rem);
                         }
@@ -427,9 +427,9 @@ int saa7164_bus_get(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf,
 
         } else {
                 /* No wrapping */
-                memcpy(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+                memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
                 if (buf)
-                        memcpy(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg),
+                        memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg),
                                 buf_size);
         }
 
diff --git a/drivers/media/video/saa7164/saa7164-core.c b/drivers/media/video/saa7164/saa7164-core.c
index e96bbe4698b9..79e1a2ee7e9e 100644
--- a/drivers/media/video/saa7164/saa7164-core.c
+++ b/drivers/media/video/saa7164/saa7164-core.c
@@ -72,6 +72,28 @@ LIST_HEAD(saa7164_devlist);
 
 #define INT_SIZE 16
 
+void saa7164_dumphex16FF(struct saa7164_dev *dev, u8 *buf, int len)
+{
+        int i;
+        u8 tmp[16];
+        memset(&tmp[0], 0xff, sizeof(tmp));
+
+        printk(KERN_INFO "--------------------> "
+                "00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f\n");
+
+        for (i = 0; i < len; i += 16) {
+                if (memcmp(&tmp, buf + i, sizeof(tmp)) != 0) {
+                        printk(KERN_INFO "         [0x%08x] "
+                                "%02x %02x %02x %02x %02x %02x %02x %02x "
+                                "%02x %02x %02x %02x %02x %02x %02x %02x\n", i,
+                        *(buf+i+0), *(buf+i+1), *(buf+i+2), *(buf+i+3),
+                        *(buf+i+4), *(buf+i+5), *(buf+i+6), *(buf+i+7),
+                        *(buf+i+8), *(buf+i+9), *(buf+i+10), *(buf+i+11),
+                        *(buf+i+12), *(buf+i+13), *(buf+i+14), *(buf+i+15));
+                }
+        }
+}
+
 static void saa7164_ts_verifier(struct saa7164_buffer *buf)
 {
         struct saa7164_port *port = buf->port;
@@ -216,6 +238,7 @@ static void saa7164_work_enchandler(struct work_struct *w)
         struct saa7164_user_buffer *ubuf;
         struct list_head *c, *n;
         int wp, rp, i = 0;
+        u32 crc, ok = 0;
         u8 *p;
 
         port->last_svc_msecs_diff = port->last_svc_msecs;
@@ -277,10 +300,19 @@ static void saa7164_work_enchandler(struct work_struct *w)
                         saa7164_dumphex16(dev, p + buf->actual_size - 32, 64);
                 }
 
+                if (buf->idx == wp) {
+                        /* Ignore this, it's being updated currently by the dma engine */
+                } else
                 if (buf->idx == rp) {
+
+                        crc = crc32(0, buf->cpu, buf->actual_size);
+                        if (crc != port->shadow_crc[rp])
+                                printk(KERN_ERR "%s crc didn't match shadow was 0x%x now 0x%x\n",
+                                        __func__, port->shadow_crc[rp], crc);
+
                         /* Found the buffer, deal with it */
-                        dprintk(DBGLVL_IRQ, "%s() wp: %d processing: %d\n",
-                                __func__, wp, rp);
+                        dprintk(DBGLVL_IRQ, "%s() wp: %d processing: %d crc32: 0x%x\n",
+                                __func__, wp, rp, buf->crc);
 
                         /* Validate the incoming buffer content */
                         if (port->encoder_params.stream_type == V4L2_MPEG_STREAM_TYPE_MPEG2_TS)
@@ -293,9 +325,23 @@ static void saa7164_work_enchandler(struct work_struct *w)
                                 ubuf = list_first_entry(&port->list_buf_free.list,
                                         struct saa7164_user_buffer, list);
 
-                                if (ubuf->actual_size == buf->actual_size) {
-                                        memcpy(ubuf->data, buf->cpu,
-                                                ubuf->actual_size);
+                                if (ubuf->actual_size >= buf->actual_size) {
+                                        memcpy(ubuf->data, port->shadow_buf[rp], 312 * 188);
+
+                                        /* Throw a new checksum on the read buffer */
+                                        ubuf->crc = crc32(0, ubuf->data, ubuf->actual_size);
+
+                                        if ((crc == port->shadow_crc[rp]) && (crc == ubuf->crc))
+                                                ok = 1;
+                                        else
+                                                ok = 0;
+
+                                        if (ok == 0)
+                                                printk(KERN_ERR
+                                                        "rp: %d dmacrc: 0x%08x shadcrc: 0x%08x ubufcrc: 0x%08x %s\n",
+                                                        rp, buf->crc, port->shadow_crc[rp], ubuf->crc,
+                                                        ok ? "crcgood" : "crcbad");
+
                                 } else {
                                         printk(KERN_ERR "buf %p actual fails match\n", buf);
                                 }
@@ -315,9 +361,21 @@ static void saa7164_work_enchandler(struct work_struct *w)
                         /* Ensure offset into buffer remains 0, fill buffer
                          * with known bad data. */
                         saa7164_buffer_zero_offsets(port, rp);
-                        memset(buf->cpu, 0xff, buf->pci_size);
+                        memset_io(buf->cpu, 0xff, buf->pci_size);
+                        buf->crc = crc32(0, buf->cpu, buf->actual_size);
+
+//                      break;
+                } else {
+                        /* Validate all other checksums, on previous buffers - they should never change */
+                        crc = crc32(0, buf->cpu, buf->actual_size);
+                        if (crc != buf->crc) {
+                                printk(KERN_ERR "buf[%d].crc became invalid, was 0x%x became 0x%x rp: %d wp: %d\n",
+                                        buf->idx, buf->crc, crc, rp, wp);
+                                //saa7164_dumphex16FF(dev, (u8 *)buf->cpu, buf->actual_size);
+                                saa7164_dumphex16FF(dev, (u8 *)buf->cpu, 256);
+                                buf->crc = crc;
+                        }
 
-                        break;
                 }
 
         }
@@ -332,7 +390,6 @@ static void saa7164_work_enchandler(struct work_struct *w)
                 print_histogram = 64 + port->nr;
         }
 }
-
 static void saa7164_work_cmdhandler(struct work_struct *w)
 {
         struct saa7164_dev *dev = container_of(w, struct saa7164_dev, workcmd);
@@ -354,7 +411,11 @@ static void saa7164_buffer_deliver(struct saa7164_buffer *buf)
 static irqreturn_t saa7164_irq_encoder(struct saa7164_port *port)
 {
         struct saa7164_dev *dev = port->dev;
-        int wp, rp;
+        struct saa7164_buffer *buf;
+        struct saa7164_user_buffer *ubuf;
+        struct list_head *c, *n;
+        int wp, rp, i = 0;
+        u8 *p;
 
         /* Find the current write point from the hardware */
         wp = saa7164_readl(port->bufcounter);
@@ -400,7 +461,48 @@ static irqreturn_t saa7164_irq_encoder(struct saa7164_port *port)
                 port->last_irq_wp,
                 port->last_irq_rp
                 );
+        /* Find the used buffer, shadow copy it before we've
+         * acked the interrupt.
+         */
+//      mutex_lock(&port->dmaqueue_lock);
+        list_for_each_safe(c, n, &port->dmaqueue.list) {
+
+                buf = list_entry(c, struct saa7164_buffer, list);
+                if (i++ > port->hwcfg.buffercount) {
+                        printk(KERN_ERR "%s() illegal i count %d\n",
+                                __func__, i);
+                        break;
+                }
+
+                p = (u8 *)buf->cpu;
+                if (    (*(p + buf->actual_size + 0) != 0xff) ||
+                        (*(p + buf->actual_size + 1) != 0xff) ||
+                        (*(p + buf->actual_size + 2) != 0xff) ||
+                        (*(p + buf->actual_size + 3) != 0xff) ||
+                        (*(p + buf->actual_size + 0x10) != 0xff) ||
+                        (*(p + buf->actual_size + 0x11) != 0xff) ||
+                        (*(p + buf->actual_size + 0x12) != 0xff) ||
+                        (*(p + buf->actual_size + 0x13) != 0xff) )
+                {
+                        printk(KERN_ERR "buf %p failed guard check\n", buf);
+                        saa7164_dumphex16(dev, p + buf->actual_size - 32, 64);
+                }
+
+                if (buf->idx == rp) {
+
+                        memcpy_fromio(port->shadow_buf[rp], buf->cpu, 312 * 188);
+                        port->shadow_crc[rp] = crc32(0, port->shadow_buf[rp], 312 * 188);
 
+                        buf->crc = crc32(0, buf->cpu, 312 * 188);
+
+                        if (port->shadow_crc[rp] != buf->crc)
+                                printk(KERN_ERR "%s() crc check failed 0x%x vs 0x%x\n",
+                                        __func__, port->shadow_crc[rp], buf->crc);
+                        break;
+                }
+
+        }
+//      mutex_unlock(&port->dmaqueue_lock);
         schedule_work(&port->workenc);
 
         return 0;
@@ -693,10 +795,10 @@ static void saa7164_dump_busdesc(struct saa7164_dev *dev)
  */
 static void saa7164_get_descriptors(struct saa7164_dev *dev)
 {
-        memcpy(&dev->hwdesc, dev->bmmio, sizeof(tmComResHWDescr_t));
-        memcpy(&dev->intfdesc, dev->bmmio + sizeof(tmComResHWDescr_t),
+        memcpy_fromio(&dev->hwdesc, dev->bmmio, sizeof(tmComResHWDescr_t));
+        memcpy_fromio(&dev->intfdesc, dev->bmmio + sizeof(tmComResHWDescr_t),
                 sizeof(tmComResInterfaceDescr_t));
-        memcpy(&dev->busdesc, dev->bmmio + dev->intfdesc.BARLocation,
+        memcpy_fromio(&dev->busdesc, dev->bmmio + dev->intfdesc.BARLocation,
                 sizeof(tmComResBusDescr_t));
 
         if (dev->hwdesc.bLength != sizeof(tmComResHWDescr_t)) {
@@ -742,6 +844,7 @@ static int get_resources(struct saa7164_dev *dev)
 static int saa7164_port_init(struct saa7164_dev *dev, int portnr)
 {
         struct saa7164_port *port = 0;
+        int i;
 
         if ((portnr < 0) || (portnr >= SAA7164_MAX_PORTS))
                 BUG();
@@ -780,6 +883,18 @@ static int saa7164_port_init(struct saa7164_dev *dev, int portnr)
         saa7164_histogram_reset(&port->poll_interval,
                 "encoder poll() intervals");
 
+        if (port->type == SAA7164_MPEG_ENCODER) {
+                for (i = 0; i < 8; i ++) {
+                        port->shadow_buf[i] = kzalloc(312 * 188, GFP_KERNEL);
+                        if (port->shadow_buf[i] == 0)
+                                printk(KERN_ERR "%s() shadow_buf ENOMEM\n", __func__);
+                        else {
+                                memset(port->shadow_buf[i], 0xff, 312 * 188);
+                                port->shadow_crc[i] = crc32(0, port->shadow_buf[i], 312 * 188);
+                        }
+                }
+        }
+
         return 0;
 }
 
@@ -1057,6 +1172,8 @@ static void saa7164_shutdown(struct saa7164_dev *dev)
 static void __devexit saa7164_finidev(struct pci_dev *pci_dev)
 {
         struct saa7164_dev *dev = pci_get_drvdata(pci_dev);
+        struct saa7164_port *port;
+        int i;
 
         saa7164_histogram_print(&dev->ports[ SAA7164_PORT_ENC1 ],
                 &dev->ports[ SAA7164_PORT_ENC1 ].irq_interval);
@@ -1071,6 +1188,22 @@ static void __devexit saa7164_finidev(struct pci_dev *pci_dev)
 
         saa7164_shutdown(dev);
 
+        port = &dev->ports[ SAA7164_PORT_ENC1 ];
+        if (port->type == SAA7164_MPEG_ENCODER) {
+                for (i = 0; i < 8; i ++) {
+                        kfree(port->shadow_buf[i]);
+                        port->shadow_buf[i] = 0;
+                }
+        }
+        port = &dev->ports[ SAA7164_PORT_ENC2 ];
+        if (port->type == SAA7164_MPEG_ENCODER) {
+                for (i = 0; i < 8; i ++) {
+                        kfree(port->shadow_buf[i]);
+                        port->shadow_buf[i] = 0;
+                }
+        }
+
+
         if (saa7164_boards[dev->board].porta == SAA7164_MPEG_DVB)
                 saa7164_dvb_unregister(&dev->ports[ SAA7164_PORT_TS1 ]);
 
diff --git a/drivers/media/video/saa7164/saa7164-encoder.c b/drivers/media/video/saa7164/saa7164-encoder.c
index c61907d0efb9..f3ecdc93e20e 100644
--- a/drivers/media/video/saa7164/saa7164-encoder.c
+++ b/drivers/media/video/saa7164/saa7164-encoder.c
@@ -865,6 +865,7 @@ static int saa7164_encoder_start_streaming(struct saa7164_port *port)
 
         /* Configure the encoder with any cache values */
         saa7164_api_set_encoder(port);
+        saa7164_api_get_encoder(port);
 
         saa7164_buffer_cfg_port(port);
 
@@ -1006,11 +1007,19 @@ struct saa7164_user_buffer *saa7164_enc_next_buf(struct saa7164_port *port)
 {
         struct saa7164_user_buffer *buf = 0;
         struct saa7164_dev *dev = port->dev;
+        u32 crc;
 
         mutex_lock(&port->dmaqueue_lock);
         if (!list_empty(&port->list_buf_used.list)) {
                 buf = list_first_entry(&port->list_buf_used.list,
                         struct saa7164_user_buffer, list);
+
+                crc = crc32(0, buf->data, buf->actual_size);
+                if (crc != buf->crc) {
+                        printk(KERN_ERR "%s() buf %p crc became invalid, was 0x%x became 0x%x\n", __func__,
+                                buf, buf->crc, crc);
+                }
+
         }
         mutex_unlock(&port->dmaqueue_lock);
 
diff --git a/drivers/media/video/saa7164/saa7164.h b/drivers/media/video/saa7164/saa7164.h
index 796d21df52b2..a8a29e56b2ce 100644
--- a/drivers/media/video/saa7164/saa7164.h
+++ b/drivers/media/video/saa7164/saa7164.h
@@ -50,6 +50,7 @@
 #include <linux/kdev_t.h>
 #include <linux/version.h>
 #include <linux/mutex.h>
+#include <linux/crc32.h>
 
 #include <media/tuner.h>
 #include <media/tveeprom.h>
@@ -194,6 +195,8 @@ struct saa7164_user_buffer {
         u8  *data;
         u32 pos;
         u32 actual_size;
+
+        u32 crc;
 };
 
 struct saa7164_fw_status {
@@ -282,12 +285,13 @@ struct saa7164_buffer {
 
         /* A block of page align PCI memory */
         u32 pci_size;   /* PCI allocation size in bytes */
-        u64 *cpu;       /* Virtual address */
+        u64 __iomem *cpu;       /* Virtual address */
         dma_addr_t dma; /* Physical address */
+        u32 crc;        /* Checksum for the entire buffer data */
 
         /* A page table that splits the block into a number of entries */
         u32 pt_size;            /* PCI allocation size in bytes */
-        u64 *pt_cpu;            /* Virtual address */
+        u64 __iomem *pt_cpu;            /* Virtual address */
         dma_addr_t pt_dma;      /* Physical address */
 
         /* Encoder fops */
@@ -386,6 +390,9 @@ struct saa7164_port {
         u32 a_cc_errors;
         u8 last_v_cc;
         u8 last_a_cc;
+
+        u8 *shadow_buf[8];
+        u32 shadow_crc[8];
 };
 
 struct saa7164_dev {
@@ -536,7 +543,6 @@ extern struct saa7164_user_buffer *saa7164_buffer_alloc_user(
 extern void saa7164_buffer_dealloc_user(struct saa7164_user_buffer *buf);
 extern int saa7164_buffer_zero_offsets(struct saa7164_port *port, int i);
 
-
 /* ----------------------------------------------------------- */
 /* saa7164-encoder.c                                            */
 int saa7164_encoder_register(struct saa7164_port *port);