V4L/DVB (7893): xc5000: bug-fix: allow multiple devices in a single system

The current code passes a context pointer in the xc5000_config struct.
This context pointer is used in the tuner_callback function, used to
reset the device after firmware download.

The xc5000_config struct is a static structure, whose .priv member was
being assigned before calling xc5000_attach().  If there are more than
one of the same device type installed on a single system, the last one
to assign xc5000_config.priv will "win", and all others will cease to
function properly.

This patch passes the context pointer in xc5000_attach() rather that
storing it within the static struct xc5000_config.

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

3 files changed, 19 insertions, 14 deletions

diff --git a/drivers/media/common/tuners/xc5000.c b/drivers/media/common/tuners/xc5000.c
index 43d35bdb221f..ceae6db901ec 100644
--- a/drivers/media/common/tuners/xc5000.c
+++ b/drivers/media/common/tuners/xc5000.c
@@ -212,7 +212,7 @@ static void xc5000_TunerReset(struct dvb_frontend *fe)
         dprintk(1, "%s()\n", __func__);
 
         if (priv->cfg->tuner_callback) {
-                ret = priv->cfg->tuner_callback(priv->cfg->priv,
+                ret = priv->cfg->tuner_callback(priv->devptr,
                                                 XC5000_TUNER_RESET, 0);
                 if (ret)
                         printk(KERN_ERR "xc5000: reset failed\n");
@@ -900,9 +900,9 @@ static const struct dvb_tuner_ops xc5000_tuner_ops = {
         .get_status        = xc5000_get_status
 };
 
-struct dvb_frontend * xc5000_attach(struct dvb_frontend *fe,
-        struct i2c_adapter *i2c,
-        struct xc5000_config *cfg)
+struct dvb_frontend *xc5000_attach(struct dvb_frontend *fe,
+                                   struct i2c_adapter *i2c,
+                                   struct xc5000_config *cfg, void *devptr)
 {
         struct xc5000_priv *priv = NULL;
         u16 id = 0;
@@ -916,6 +916,7 @@ struct dvb_frontend * xc5000_attach(struct dvb_frontend *fe,
         priv->cfg = cfg;
         priv->bandwidth = BANDWIDTH_6_MHZ;
         priv->i2c = i2c;
+        priv->devptr = devptr;
 
         /* Check if firmware has been loaded. It is possible that another
            instance of the driver has loaded the firmware.
diff --git a/drivers/media/common/tuners/xc5000.h b/drivers/media/common/tuners/xc5000.h
index 0ee80f9d19b8..c910715addc9 100644
--- a/drivers/media/common/tuners/xc5000.h
+++ b/drivers/media/common/tuners/xc5000.h
@@ -31,29 +31,31 @@ struct xc5000_config {
         u8   i2c_address;
         u32  if_khz;
 
-        /* For each bridge framework, when it attaches either analog or digital,
-         * it has to store a reference back to its _core equivalent structure,
-         * so that it can service the hardware by steering gpio's etc.
-         * Each bridge implementation is different so cast priv accordingly.
-         * The xc5000 driver cares not for this value, other than ensuring
-         * it's passed back to a bridge during tuner_callback().
-         */
-        void *priv;
         int  (*tuner_callback) (void *priv, int command, int arg);
 };
 
 /* xc5000 callback command */
 #define XC5000_TUNER_RESET              0
 
+/* For each bridge framework, when it attaches either analog or digital,
+ * it has to store a reference back to its _core equivalent structure,
+ * so that it can service the hardware by steering gpio's etc.
+ * Each bridge implementation is different so cast devptr accordingly.
+ * The xc5000 driver cares not for this value, other than ensuring
+ * it's passed back to a bridge during tuner_callback().
+ */
+
 #if defined(CONFIG_MEDIA_TUNER_XC5000) || \
     (defined(CONFIG_MEDIA_TUNER_XC5000_MODULE) && defined(MODULE))
 extern struct dvb_frontend* xc5000_attach(struct dvb_frontend *fe,
                                           struct i2c_adapter *i2c,
-                                          struct xc5000_config *cfg);
+                                          struct xc5000_config *cfg,
+                                          void *devptr);
 #else
 static inline struct dvb_frontend* xc5000_attach(struct dvb_frontend *fe,
                                                  struct i2c_adapter *i2c,
-                                                 struct xc5000_config *cfg)
+                                                 struct xc5000_config *cfg,
+                                                 void *devptr)
 {
         printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
         return NULL;
diff --git a/drivers/media/common/tuners/xc5000_priv.h b/drivers/media/common/tuners/xc5000_priv.h
index 13b2d19341da..ecebfe4745ad 100644
--- a/drivers/media/common/tuners/xc5000_priv.h
+++ b/drivers/media/common/tuners/xc5000_priv.h
@@ -31,6 +31,8 @@ struct xc5000_priv {
         u8  video_standard;
         u8  rf_mode;
         u8  fwloaded;
+
+        void *devptr;
 };
 
 #endif