--- a/drivers/media/dvb/ttpci/budget-av.c	2008-07-13 23:51:29.000000000 +0200
+++ b/drivers/media/dvb/ttpci/budget-av.c	2008-08-18 21:53:10.000000000 +0200
@@ -65,10 +65,11 @@ struct budget_av {
 	struct tasklet_struct ciintf_irq_tasklet;
 	int slot_status;
 	struct dvb_ca_en50221 ca;
+	struct mutex camlock;
 	u8 reinitialise_demod:1;
 };
 
-static int ciintf_slot_shutdown(struct dvb_ca_en50221 *ca, int slot);
+static int ciintf_unlocked_slot_shutdown(struct dvb_ca_en50221 *ca, int slot);
 
 
 /* GPIO Connections:
@@ -128,7 +129,7 @@ static int i2c_writereg(struct i2c_adapt
 	return i2c_transfer(i2c, &msgs, 1);
 }
 
-static int ciintf_read_attribute_mem(struct dvb_ca_en50221 *ca, int slot, int address)
+static int ciintf_unlocked_read_attribute_mem(struct dvb_ca_en50221 *ca, int slot, int address)
 {
 	struct budget_av *budget_av = (struct budget_av *) ca->data;
 	int result;
@@ -141,9 +142,22 @@ static int ciintf_read_attribute_mem(str
 
 	result = ttpci_budget_debiread(&budget_av->budget, DEBICICAM, address & 0xfff, 1, 0, 1);
 	if (result == -ETIMEDOUT) {
-		ciintf_slot_shutdown(ca, slot);
+		ciintf_unlocked_slot_shutdown(ca, slot);
 		printk(KERN_INFO "budget-av: cam ejected 1\n");
 	}
+
+	return result;
+}
+
+static int ciintf_read_attribute_mem(struct dvb_ca_en50221 *ca, int slot, int address)
+{
+	struct budget_av *budget_av = (struct budget_av *) ca->data;
+	int result;
+
+	mutex_lock(&budget_av->camlock);
+	result = ciintf_unlocked_read_attribute_mem(ca, slot, address);
+	mutex_unlock(&budget_av->camlock);
+
 	return result;
 }
 
@@ -155,14 +169,19 @@ static int ciintf_write_attribute_mem(st
 	if (slot != 0)
 		return -EINVAL;
 
+	mutex_lock(&budget_av->camlock);
+
 	saa7146_setgpio(budget_av->budget.dev, 1, SAA7146_GPIO_OUTHI);
 	udelay(1);
 
 	result = ttpci_budget_debiwrite(&budget_av->budget, DEBICICAM, address & 0xfff, 1, value, 0, 1);
 	if (result == -ETIMEDOUT) {
-		ciintf_slot_shutdown(ca, slot);
+		ciintf_unlocked_slot_shutdown(ca, slot);
 		printk(KERN_INFO "budget-av: cam ejected 2\n");
 	}
+
+	mutex_unlock(&budget_av->camlock);
+
 	return result;
 }
 
@@ -174,15 +193,19 @@ static int ciintf_read_cam_control(struc
 	if (slot != 0)
 		return -EINVAL;
 
+	mutex_lock(&budget_av->camlock);
+
 	saa7146_setgpio(budget_av->budget.dev, 1, SAA7146_GPIO_OUTLO);
 	udelay(1);
 
 	result = ttpci_budget_debiread(&budget_av->budget, DEBICICAM, address & 3, 1, 0, 0);
 	if (result == -ETIMEDOUT) {
-		ciintf_slot_shutdown(ca, slot);
+		ciintf_unlocked_slot_shutdown(ca, slot);
 		printk(KERN_INFO "budget-av: cam ejected 3\n");
-		return -ETIMEDOUT;
 	}
+
+	mutex_unlock(&budget_av->camlock);
+
 	return result;
 }
 
@@ -194,14 +217,19 @@ static int ciintf_write_cam_control(stru
 	if (slot != 0)
 		return -EINVAL;
 
+	mutex_lock(&budget_av->camlock);
+
 	saa7146_setgpio(budget_av->budget.dev, 1, SAA7146_GPIO_OUTLO);
 	udelay(1);
 
 	result = ttpci_budget_debiwrite(&budget_av->budget, DEBICICAM, address & 3, 1, value, 0, 0);
 	if (result == -ETIMEDOUT) {
-		ciintf_slot_shutdown(ca, slot);
+		ciintf_unlocked_slot_shutdown(ca, slot);
 		printk(KERN_INFO "budget-av: cam ejected 5\n");
 	}
+
+	mutex_unlock(&budget_av->camlock);
+
 	return result;
 }
 
@@ -213,6 +241,8 @@ static int ciintf_slot_reset(struct dvb_
 	if (slot != 0)
 		return -EINVAL;
 
+	mutex_lock(&budget_av->camlock);
+
 	dprintk(1, "ciintf_slot_reset\n");
 	budget_av->slot_status = SLOTSTATUS_RESET;
 
@@ -231,10 +261,12 @@ static int ciintf_slot_reset(struct dvb_
 	if (budget_av->reinitialise_demod)
 		dvb_frontend_reinitialise(budget_av->budget.dvb_frontend);
 
+	mutex_unlock(&budget_av->camlock);
+
 	return 0;
 }
 
-static int ciintf_slot_shutdown(struct dvb_ca_en50221 *ca, int slot)
+static int ciintf_unlocked_slot_shutdown(struct dvb_ca_en50221 *ca, int slot)
 {
 	struct budget_av *budget_av = (struct budget_av *) ca->data;
 	struct saa7146_dev *saa = budget_av->budget.dev;
@@ -250,6 +282,18 @@ static int ciintf_slot_shutdown(struct d
 	return 0;
 }
 
+static int ciintf_slot_shutdown(struct dvb_ca_en50221 *ca, int slot)
+{
+	struct budget_av *budget_av = (struct budget_av *) ca->data;
+	int result;
+
+	mutex_lock(&budget_av->camlock);
+	result = ciintf_unlocked_slot_shutdown(ca, slot);
+	mutex_unlock(&budget_av->camlock);
+
+	return result;
+}
+
 static int ciintf_slot_ts_enable(struct dvb_ca_en50221 *ca, int slot)
 {
 	struct budget_av *budget_av = (struct budget_av *) ca->data;
@@ -258,10 +302,13 @@ static int ciintf_slot_ts_enable(struct 
 	if (slot != 0)
 		return -EINVAL;
 
-	dprintk(1, "ciintf_slot_ts_enable: %d\n", budget_av->slot_status);
+	mutex_lock(&budget_av->camlock);
 
+	dprintk(1, "ciintf_slot_ts_enable: %d\n", budget_av->slot_status);
 	ttpci_budget_set_video_port(saa, BUDGET_VIDEO_PORTA);
 
+	mutex_unlock(&budget_av->camlock);
+
 	return 0;
 }
 
@@ -274,6 +321,8 @@ static int ciintf_poll_slot_status(struc
 	if (slot != 0)
 		return -EINVAL;
 
+	mutex_lock(&budget_av->camlock);
+
 	/* test the card detect line - needs to be done carefully
 	 * since it never goes high for some CAMs on this interface (e.g. topuptv) */
 	if (budget_av->slot_status == SLOTSTATUS_NONE) {
@@ -302,8 +351,9 @@ static int ciintf_poll_slot_status(struc
 			printk(KERN_INFO "budget-av: cam inserted B\n");
 		} else if (result < 0) {
 			if (budget_av->slot_status != SLOTSTATUS_NONE) {
-				ciintf_slot_shutdown(ca, slot);
+				ciintf_unlocked_slot_shutdown(ca, slot);
 				printk(KERN_INFO "budget-av: cam ejected 5\n");
+				mutex_unlock(&budget_av->camlock);
 				return 0;
 			}
 		}
@@ -311,20 +361,23 @@ static int ciintf_poll_slot_status(struc
 
 	/* read from attribute memory in reset/ready state to know when the CAM is ready */
 	if (budget_av->slot_status == SLOTSTATUS_RESET) {
-		result = ciintf_read_attribute_mem(ca, slot, 0);
+		result = ciintf_unlocked_read_attribute_mem(ca, slot, 0);
 		if (result == 0x1d) {
 			budget_av->slot_status = SLOTSTATUS_READY;
 		}
 	}
 
 	/* work out correct return code */
+	result = 0;
 	if (budget_av->slot_status != SLOTSTATUS_NONE) {
-		if (budget_av->slot_status & SLOTSTATUS_READY) {
-			return DVB_CA_EN50221_POLL_CAM_PRESENT | DVB_CA_EN50221_POLL_CAM_READY;
-		}
-		return DVB_CA_EN50221_POLL_CAM_PRESENT;
+		result = DVB_CA_EN50221_POLL_CAM_PRESENT;
+		if (budget_av->slot_status & SLOTSTATUS_READY)
+			result |= DVB_CA_EN50221_POLL_CAM_READY;
 	}
-	return 0;
+
+	mutex_unlock(&budget_av->camlock);
+
+	return result;
 }
 
 static int ciintf_init(struct budget_av *budget_av)
@@ -332,6 +385,7 @@ static int ciintf_init(struct budget_av 
 	struct saa7146_dev *saa = budget_av->budget.dev;
 	int result;
 
+	mutex_init(&budget_av->camlock);
 	memset(&budget_av->ca, 0, sizeof(struct dvb_ca_en50221));
 
 	saa7146_setgpio(saa, 0, SAA7146_GPIO_OUTLO);