V4L/DVB (6429): Avoid having two tuner commands happening at the same time

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 30 insertions, 10 deletions

diff --git a/drivers/media/video/tuner-xc2028.c b/drivers/media/video/tuner-xc2028.c
index 78e83700a13c..0e68002a4a04 100644
--- a/drivers/media/video/tuner-xc2028.c
+++ b/drivers/media/video/tuner-xc2028.c
@@ -12,6 +12,7 @@
 #include <linux/videodev.h>
 #include <linux/delay.h>
 #include <media/tuner.h>
+#include <linux/mutex.h>
 #include "tuner-driver.h"
 #include "tuner-xc2028.h"
 
@@ -47,6 +48,8 @@ struct xc2028_data {
                                                               were loaded? */
         enum tuner_mode mode;
         struct i2c_client       *i2c_client;
+        
+        struct mutex lock;
 };
 
 #define i2c_send(rc,c,buf,size)                                         \
@@ -286,20 +289,28 @@ static int check_firmware(struct i2c_client *c, enum tuner_mode new_mode,
 
 static int xc2028_signal(struct i2c_client *c)
 {
-        int lock, signal;
+        struct tuner       *t = i2c_get_clientdata(c);
+        struct xc2028_data *xc2028 = t->priv;
+        int                frq_lock, signal=0;
+
+        mutex_lock(&xc2028->lock);
 
         printk(KERN_INFO "xc2028: %s called\n", __FUNCTION__);
 
-        lock = xc2028_get_reg(c, 0x2);
-        if (lock<=0)
-                return lock;
+        frq_lock = xc2028_get_reg(c, 0x2);
+        if (frq_lock<=0)
+                goto ret;
 
         /* Frequency is locked. Return signal quality */
 
         signal = xc2028_get_reg(c, 0x40);
 
-        if(signal<=0)
-                return lock;
+        if(signal<=0) {
+                signal=frq_lock;
+        }
+
+ret:
+        mutex_unlock(&xc2028->lock);
 
         return signal;
 }
@@ -318,6 +329,8 @@ static void generic_set_tv_freq(struct i2c_client *c, u32 freq /* in Hz */,
            when freq is changed */
         struct xc2028_data      *xc2028 = t->priv;
 
+        mutex_lock(&xc2028->lock);
+
         xc2028->firm_type=0;
 
         /* Reset GPIO 1 */
@@ -325,13 +338,13 @@ static void generic_set_tv_freq(struct i2c_client *c, u32 freq /* in Hz */,
                 rc = t->tuner_callback( c->adapter->algo_data,
                                         XC2028_TUNER_RESET, 0);
                 if (rc<0)
-                        return;
+                        goto ret;
         }
         msleep(10);
         printk("xc3028: should set frequency %d kHz)\n", freq / 1000);
 
         if (check_firmware(c, new_mode, bandwidth)<0)
-                return;
+                goto ret;
 
         if(new_mode == T_DIGITAL_TV)
                 offset = 2750000;
@@ -344,7 +357,7 @@ static void generic_set_tv_freq(struct i2c_client *c, u32 freq /* in Hz */,
                 rc = t->tuner_callback( c->adapter->algo_data,
                                         XC2028_RESET_CLK, 1);
                 if (rc<0)
-                        return;
+                        goto ret;
         }
 
         msleep(10);
@@ -357,12 +370,15 @@ static void generic_set_tv_freq(struct i2c_client *c, u32 freq /* in Hz */,
 
         i2c_send(rc, c, buf, sizeof(buf));
         if (rc<0)
-                return;
+                goto ret;
         msleep(100);
 
         printk("divider= %02x %02x %02x %02x (freq=%d.%02d)\n",
                  buf[1],buf[2],buf[3],buf[4],
                  freq / 16, freq % 16 * 100 / 16);
+
+ret:
+        mutex_unlock(&xc2028->lock);
 }
 
 
@@ -416,6 +432,8 @@ int xc2028_tuner_init(struct i2c_client *c)
         xc2028->need_load_generic=1;
         xc2028->mode = T_UNINITIALIZED;
 
+        mutex_init(&xc2028->lock);
+
         /* FIXME: Check where t->priv will be freed */
 
         if (version<0)
@@ -498,5 +516,7 @@ int xc2028_attach(struct i2c_client *c, struct dvb_frontend *fe)
         return 0;
 }
 
+
+
 EXPORT_SYMBOL(xc2028_attach);