V4L/DVB (10743): dm1105: not demuxing from interrupt context.

The driver already has DMA buffer organized like ringbuffer,
so it is easy to switch to a work queue.
Length of ringbuffer can easily be increased, if someone need it.

Signed-off-by: Igor M. Liplianin <liplianin@netup.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 60 insertions, 50 deletions

diff --git a/drivers/media/dvb/dm1105/dm1105.c b/drivers/media/dvb/dm1105/dm1105.c
index f48f73aff195..d9f55beb4890 100644
--- a/drivers/media/dvb/dm1105/dm1105.c
+++ b/drivers/media/dvb/dm1105/dm1105.c
@@ -220,10 +220,14 @@ struct dm1105dvb {
         /* i2c */
         struct i2c_adapter i2c_adap;
 
+        /* irq */
+        struct work_struct work;
+
         /* dma */
         dma_addr_t dma_addr;
         unsigned char *ts_buf;
         u32 wrp;
+        u32 nextwrp;
         u32 buffer_size;
         unsigned int    PacketErrorCount;
         unsigned int dmarst;
@@ -415,6 +419,9 @@ static void dm1105_emit_key(unsigned long parm)
         u8 data;
         u16 keycode;
 
+        if (ir_debug)
+                printk(KERN_INFO "%s: received byte 0x%04x\n", __func__, ircom);
+
         data = (ircom >> 8) & 0x7f;
 
         input_event(ir->input_dev, EV_MSC, MSC_RAW, (0x0000f8 << 16) | data);
@@ -431,14 +438,45 @@ static void dm1105_emit_key(unsigned long parm)
 
 }
 
+/* work handler */
+static void dm1105_dmx_buffer(struct work_struct *work)
+{
+        struct dm1105dvb *dm1105dvb =
+                                container_of(work, struct dm1105dvb, work);
+        unsigned int nbpackets;
+        u32 oldwrp = dm1105dvb->wrp;
+        u32 nextwrp = dm1105dvb->nextwrp;
+
+        if (!((dm1105dvb->ts_buf[oldwrp] == 0x47) &&
+                        (dm1105dvb->ts_buf[oldwrp + 188] == 0x47) &&
+                        (dm1105dvb->ts_buf[oldwrp + 188 * 2] == 0x47))) {
+                dm1105dvb->PacketErrorCount++;
+                /* bad packet found */
+                if ((dm1105dvb->PacketErrorCount >= 2) &&
+                                (dm1105dvb->dmarst == 0)) {
+                        outb(1, dm_io_mem(DM1105_RST));
+                        dm1105dvb->wrp = 0;
+                        dm1105dvb->PacketErrorCount = 0;
+                        dm1105dvb->dmarst = 0;
+                        return;
+                }
+        }
+
+        if (nextwrp < oldwrp) {
+                memcpy(dm1105dvb->ts_buf + dm1105dvb->buffer_size,
+                                                dm1105dvb->ts_buf, nextwrp);
+                nbpackets = ((dm1105dvb->buffer_size - oldwrp) + nextwrp) / 188;
+        } else
+                nbpackets = (nextwrp - oldwrp) / 188;
+
+        dm1105dvb->wrp = nextwrp;
+        dvb_dmx_swfilter_packets(&dm1105dvb->demux,
+                                        &dm1105dvb->ts_buf[oldwrp], nbpackets);
+}
+
 static irqreturn_t dm1105dvb_irq(int irq, void *dev_id)
 {
         struct dm1105dvb *dm1105dvb = dev_id;
-        unsigned int piece;
-        unsigned int nbpackets;
-        u32 command;
-        u32 nextwrp;
-        u32 oldwrp;
 
         /* Read-Write INSTS Ack's Interrupt for DM1105 chip 16.03.2008 */
         unsigned int intsts = inb(dm_io_mem(DM1105_INTSTS));
@@ -447,48 +485,17 @@ static irqreturn_t dm1105dvb_irq(int irq, void *dev_id)
         switch (intsts) {
         case INTSTS_TSIRQ:
         case (INTSTS_TSIRQ | INTSTS_IR):
-                nextwrp = inl(dm_io_mem(DM1105_WRP)) -
-                        inl(dm_io_mem(DM1105_STADR)) ;
-                oldwrp = dm1105dvb->wrp;
-                spin_lock(&dm1105dvb->lock);
-                if (!((dm1105dvb->ts_buf[oldwrp] == 0x47) &&
-                                (dm1105dvb->ts_buf[oldwrp + 188] == 0x47) &&
-                                (dm1105dvb->ts_buf[oldwrp + 188 * 2] == 0x47))) {
-                        dm1105dvb->PacketErrorCount++;
-                        /* bad packet found */
-                        if ((dm1105dvb->PacketErrorCount >= 2) &&
-                                        (dm1105dvb->dmarst == 0)) {
-                                outb(1, dm_io_mem(DM1105_RST));
-                                dm1105dvb->wrp = 0;
-                                dm1105dvb->PacketErrorCount = 0;
-                                dm1105dvb->dmarst = 0;
-                                spin_unlock(&dm1105dvb->lock);
-                                return IRQ_HANDLED;
-                        }
-                }
-                if (nextwrp < oldwrp) {
-                        piece = dm1105dvb->buffer_size - oldwrp;
-                        memcpy(dm1105dvb->ts_buf + dm1105dvb->buffer_size, dm1105dvb->ts_buf, nextwrp);
-                        nbpackets = (piece + nextwrp)/188;
-                } else  {
-                        nbpackets = (nextwrp - oldwrp)/188;
-                }
-                dvb_dmx_swfilter_packets(&dm1105dvb->demux, &dm1105dvb->ts_buf[oldwrp], nbpackets);
-                dm1105dvb->wrp = nextwrp;
-                spin_unlock(&dm1105dvb->lock);
+                dm1105dvb->nextwrp = inl(dm_io_mem(DM1105_WRP)) -
+                                        inl(dm_io_mem(DM1105_STADR));
+                schedule_work(&dm1105dvb->work);
                 break;
         case INTSTS_IR:
-                command = inl(dm_io_mem(DM1105_IRCODE));
-                if (ir_debug)
-                        printk("dm1105: received byte 0x%04x\n", command);
-
-                dm1105dvb->ir.ir_command = command;
+                dm1105dvb->ir.ir_command = inl(dm_io_mem(DM1105_IRCODE));
                 tasklet_schedule(&dm1105dvb->ir.ir_tasklet);
                 break;
         }
-        return IRQ_HANDLED;
-
 
+        return IRQ_HANDLED;
 }
 
 /* register with input layer */
@@ -710,7 +717,7 @@ static int __devinit dm1105_probe(struct pci_dev *pdev,
 
         dm1105dvb = kzalloc(sizeof(struct dm1105dvb), GFP_KERNEL);
         if (!dm1105dvb)
-                goto out;
+                return -ENOMEM;
 
         dm1105dvb->pdev = pdev;
         dm1105dvb->buffer_size = 5 * DM1105_DMA_BYTES;
@@ -740,13 +747,9 @@ static int __devinit dm1105_probe(struct pci_dev *pdev,
         spin_lock_init(&dm1105dvb->lock);
         pci_set_drvdata(pdev, dm1105dvb);
 
-        ret = request_irq(pdev->irq, dm1105dvb_irq, IRQF_SHARED, DRIVER_NAME, dm1105dvb);
-        if (ret < 0)
-                goto err_pci_iounmap;
-
         ret = dm1105dvb_hw_init(dm1105dvb);
         if (ret < 0)
-                goto err_free_irq;
+                goto err_pci_iounmap;
 
         /* i2c */
         i2c_set_adapdata(&dm1105dvb->i2c_adap, dm1105dvb);
@@ -813,8 +816,15 @@ static int __devinit dm1105_probe(struct pci_dev *pdev,
 
         dvb_net_init(dvb_adapter, &dm1105dvb->dvbnet, dmx);
         dm1105_ir_init(dm1105dvb);
-out:
-        return ret;
+
+        INIT_WORK(&dm1105dvb->work, dm1105_dmx_buffer);
+
+        ret = request_irq(pdev->irq, dm1105dvb_irq, IRQF_SHARED,
+                                                DRIVER_NAME, dm1105dvb);
+        if (ret < 0)
+                goto err_free_irq;
+
+        return 0;
 
 err_disconnect_frontend:
         dmx->disconnect_frontend(dmx);
@@ -843,7 +853,7 @@ err_pci_disable_device:
 err_kfree:
         pci_set_drvdata(pdev, NULL);
         kfree(dm1105dvb);
-        goto out;
+        return ret;
 }
 
 static void __devexit dm1105_remove(struct pci_dev *pdev)