[media] au0828: Add option to preallocate digital transfer buffers

Added command line parameter preallocate_big_buffers so that the digital
transfer buffers can be allocated when the driver is registered. They
do not have to be allocated every time a feed is started.

Signed-off-by: Tim Mester <tmester@ieee.org>
Acked-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

3 files changed, 57 insertions, 7 deletions

diff --git a/drivers/media/usb/au0828/au0828-core.c b/drivers/media/usb/au0828/au0828-core.c
index bd9d19a73efd..ab45a6f9dcc9 100644
--- a/drivers/media/usb/au0828/au0828-core.c
+++ b/drivers/media/usb/au0828/au0828-core.c
@@ -173,9 +173,8 @@ static int au0828_usb_probe(struct usb_interface *interface,
         const struct usb_device_id *id)
 {
         int ifnum;
-#ifdef CONFIG_VIDEO_AU0828_V4L2
-        int retval;
-#endif
+        int retval = 0;
+
         struct au0828_dev *dev;
         struct usb_device *usbdev = interface_to_usbdev(interface);
 
@@ -257,7 +256,11 @@ static int au0828_usb_probe(struct usb_interface *interface,
 #endif
 
         /* Digital TV */
-        au0828_dvb_register(dev);
+        retval = au0828_dvb_register(dev);
+        if (retval)
+                pr_err("%s() au0282_dev_register failed\n",
+                       __func__);
+
 
         /* Store the pointer to the au0828_dev so it can be accessed in
            au0828_usb_disconnect */
@@ -268,7 +271,7 @@ static int au0828_usb_probe(struct usb_interface *interface,
 
         mutex_unlock(&dev->lock);
 
-        return 0;
+        return retval;
 }
 
 static struct usb_driver au0828_usb_driver = {
diff --git a/drivers/media/usb/au0828/au0828-dvb.c b/drivers/media/usb/au0828/au0828-dvb.c
index 3c718dbeae71..19fe049aeb5e 100644
--- a/drivers/media/usb/au0828/au0828-dvb.c
+++ b/drivers/media/usb/au0828/au0828-dvb.c
@@ -33,6 +33,10 @@
 #include "mxl5007t.h"
 #include "tda18271.h"
 
+int preallocate_big_buffers;
+module_param_named(preallocate_big_buffers, preallocate_big_buffers, int, 0644);
+MODULE_PARM_DESC(preallocate_big_buffers, "Preallocate the larger transfer buffers at module load time");
+
 DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
 
 #define _AU0828_BULKPIPE 0x83
@@ -155,7 +159,9 @@ static int stop_urb_transfer(struct au0828_dev *dev)
         for (i = 0; i < URB_COUNT; i++) {
                 if (dev->urbs[i]) {
                         usb_kill_urb(dev->urbs[i]);
-                        kfree(dev->urbs[i]->transfer_buffer);
+                        if (!preallocate_big_buffers)
+                                kfree(dev->urbs[i]->transfer_buffer);
+
                         usb_free_urb(dev->urbs[i]);
                 }
         }
@@ -183,7 +189,12 @@ static int start_urb_transfer(struct au0828_dev *dev)
 
                 purb = dev->urbs[i];
 
-                purb->transfer_buffer = kzalloc(URB_BUFSIZE, GFP_KERNEL);
+                if (preallocate_big_buffers)
+                        purb->transfer_buffer = dev->dig_transfer_buffer[i];
+                else
+                        purb->transfer_buffer = kzalloc(URB_BUFSIZE,
+                                        GFP_KERNEL);
+
                 if (!purb->transfer_buffer) {
                         usb_free_urb(purb);
                         dev->urbs[i] = NULL;
@@ -334,6 +345,23 @@ static int dvb_register(struct au0828_dev *dev)
 
         dprintk(1, "%s()\n", __func__);
 
+        if (preallocate_big_buffers) {
+                int i;
+                for (i = 0; i < URB_COUNT; i++) {
+                        dev->dig_transfer_buffer[i] = kzalloc(URB_BUFSIZE,
+                                        GFP_KERNEL);
+
+                        if (!dev->dig_transfer_buffer[i]) {
+                                result = -ENOMEM;
+
+                                printk(KERN_ERR
+                                       "%s: failed buffer allocation (errno = %d)\n",
+                                       DRIVER_NAME, result);
+                                goto fail_adapter;
+                        }
+                }
+        }
+
         INIT_WORK(&dev->restart_streaming, au0828_restart_dvb_streaming);
 
         /* register adapter */
@@ -424,6 +452,13 @@ fail_frontend:
         dvb_frontend_detach(dvb->frontend);
         dvb_unregister_adapter(&dvb->adapter);
 fail_adapter:
+
+        if (preallocate_big_buffers) {
+                int i;
+                for (i = 0; i < URB_COUNT; i++)
+                        kfree(dev->dig_transfer_buffer[i]);
+        }
+
         return result;
 }
 
@@ -444,6 +479,14 @@ void au0828_dvb_unregister(struct au0828_dev *dev)
         dvb_unregister_frontend(dvb->frontend);
         dvb_frontend_detach(dvb->frontend);
         dvb_unregister_adapter(&dvb->adapter);
+
+        if (preallocate_big_buffers) {
+                int i;
+                for (i = 0; i < URB_COUNT; i++)
+                        kfree(dev->dig_transfer_buffer[i]);
+        }
+
+
 }
 
 /* All the DVB attach calls go here, this function get's modified
diff --git a/drivers/media/usb/au0828/au0828.h b/drivers/media/usb/au0828/au0828.h
index a00b400f8703..5439772c1551 100644
--- a/drivers/media/usb/au0828/au0828.h
+++ b/drivers/media/usb/au0828/au0828.h
@@ -262,6 +262,10 @@ struct au0828_dev {
         /* USB / URB Related */
         int             urb_streaming;
         struct urb      *urbs[URB_COUNT];
+
+        /* Preallocated transfer digital transfer buffers */
+
+        char *dig_transfer_buffer[URB_COUNT];
 };
 
 /* ----------------------------------------------------------- */