i2c: Add support for custom probe function

The probe method used by i2c_new_probed_device() may not be suitable
for all cases. Let the caller provide its own, optional probe
function.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>

11 files changed, 31 insertions, 21 deletions

diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices
index e89490270aba..87da405a8597 100644
--- a/Documentation/i2c/instantiating-devices
+++ b/Documentation/i2c/instantiating-devices
@@ -102,7 +102,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
         memset(&i2c_info, 0, sizeof(struct i2c_board_info));
         strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE);
         isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info,
-                                                   normal_i2c);
+                                                   normal_i2c, NULL);
         i2c_put_adapter(i2c_adap);
         (...)
 }
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index df937df845eb..cf14ca063181 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1464,14 +1464,18 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
 struct i2c_client *
 i2c_new_probed_device(struct i2c_adapter *adap,
                       struct i2c_board_info *info,
-                      unsigned short const *addr_list)
+                      unsigned short const *addr_list,
+                      int (*probe)(struct i2c_adapter *, unsigned short addr))
 {
         int i;
 
-        /* Stop here if the bus doesn't support probing */
-        if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
-                dev_err(&adap->dev, "Probing not supported\n");
-                return NULL;
+        if (!probe) {
+                /* Stop here if the bus doesn't support probing */
+                if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
+                        dev_err(&adap->dev, "Probing not supported\n");
+                        return NULL;
+                }
+                probe = i2c_default_probe;
         }
 
         for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
@@ -1490,7 +1494,7 @@ i2c_new_probed_device(struct i2c_adapter *adap,
                 }
 
                 /* Test address responsiveness */
-                if (i2c_default_probe(adap, addr_list[i]))
+                if (probe(adap, addr_list[i]))
                         break;
         }
 
diff --git a/drivers/macintosh/therm_windtunnel.c b/drivers/macintosh/therm_windtunnel.c
index 5c9367acf0cf..7d1bfeb6a82c 100644
--- a/drivers/macintosh/therm_windtunnel.c
+++ b/drivers/macintosh/therm_windtunnel.c
@@ -322,10 +322,10 @@ do_attach( struct i2c_adapter *adapter )
 
                 memset(&info, 0, sizeof(struct i2c_board_info));
                 strlcpy(info.type, "therm_ds1775", I2C_NAME_SIZE);
-                i2c_new_probed_device(adapter, &info, scan_ds1775);
+                i2c_new_probed_device(adapter, &info, scan_ds1775, NULL);
 
                 strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE);
-                i2c_new_probed_device(adapter, &info, scan_adm1030);
+                i2c_new_probed_device(adapter, &info, scan_adm1030, NULL);
 
                 if( x.thermostat && x.fan ) {
                         x.running = 1;
diff --git a/drivers/media/video/bt8xx/bttv-i2c.c b/drivers/media/video/bt8xx/bttv-i2c.c
index 407fa61e4cda..685d6597ee79 100644
--- a/drivers/media/video/bt8xx/bttv-i2c.c
+++ b/drivers/media/video/bt8xx/bttv-i2c.c
@@ -411,7 +411,7 @@ void __devinit init_bttv_i2c_ir(struct bttv *btv)
 
                 memset(&info, 0, sizeof(struct i2c_board_info));
                 strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
-                i2c_new_probed_device(&btv->c.i2c_adap, &info, addr_list);
+                i2c_new_probed_device(&btv->c.i2c_adap, &info, addr_list, NULL);
         }
 }
 
diff --git a/drivers/media/video/cx18/cx18-i2c.c b/drivers/media/video/cx18/cx18-i2c.c
index 809f7d37129c..73ce90c2f577 100644
--- a/drivers/media/video/cx18/cx18-i2c.c
+++ b/drivers/media/video/cx18/cx18-i2c.c
@@ -117,7 +117,8 @@ static int cx18_i2c_new_ir(struct cx18 *cx, struct i2c_adapter *adap, u32 hw,
                 break;
         }
 
-        return i2c_new_probed_device(adap, &info, addr_list) == NULL ? -1 : 0;
+        return i2c_new_probed_device(adap, &info, addr_list, NULL) == NULL ?
+               -1 : 0;
 }
 
 int cx18_i2c_register(struct cx18 *cx, unsigned idx)
diff --git a/drivers/media/video/em28xx/em28xx-cards.c b/drivers/media/video/em28xx/em28xx-cards.c
index ffbe544e30f4..e7efb4bffabd 100644
--- a/drivers/media/video/em28xx/em28xx-cards.c
+++ b/drivers/media/video/em28xx/em28xx-cards.c
@@ -2385,7 +2385,7 @@ void em28xx_register_i2c_ir(struct em28xx *dev)
 
         if (dev->init_data.name)
                 info.platform_data = &dev->init_data;
-        i2c_new_probed_device(&dev->i2c_adap, &info, addr_list);
+        i2c_new_probed_device(&dev->i2c_adap, &info, addr_list, NULL);
 }
 
 void em28xx_card_setup(struct em28xx *dev)
diff --git a/drivers/media/video/ivtv/ivtv-i2c.c b/drivers/media/video/ivtv/ivtv-i2c.c
index d391bbdb0b8a..a74fa099c565 100644
--- a/drivers/media/video/ivtv/ivtv-i2c.c
+++ b/drivers/media/video/ivtv/ivtv-i2c.c
@@ -183,8 +183,8 @@ static int ivtv_i2c_new_ir(struct ivtv *itv, u32 hw, const char *type, u8 addr)
                         return -1;
                 memset(&info, 0, sizeof(struct i2c_board_info));
                 strlcpy(info.type, type, I2C_NAME_SIZE);
-                return i2c_new_probed_device(adap, &info, addr_list) == NULL
-                                                                     ? -1 : 0;
+                return i2c_new_probed_device(adap, &info, addr_list, NULL)
+                                                           == NULL ? -1 : 0;
         }
 
         /* Only allow one IR receiver to be registered per board */
@@ -221,7 +221,8 @@ static int ivtv_i2c_new_ir(struct ivtv *itv, u32 hw, const char *type, u8 addr)
         info.platform_data = init_data;
         strlcpy(info.type, type, I2C_NAME_SIZE);
 
-        return i2c_new_probed_device(adap, &info, addr_list) == NULL ? -1 : 0;
+        return i2c_new_probed_device(adap, &info, addr_list, NULL) == NULL ?
+               -1 : 0;
 }
 
 /* Instantiate the IR receiver device using probing -- undesirable */
@@ -249,7 +250,7 @@ struct i2c_client *ivtv_i2c_new_ir_legacy(struct ivtv *itv)
 
         memset(&info, 0, sizeof(struct i2c_board_info));
         strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
-        return i2c_new_probed_device(&itv->i2c_adap, &info, addr_list);
+        return i2c_new_probed_device(&itv->i2c_adap, &info, addr_list, NULL);
 }
 
 int ivtv_i2c_register(struct ivtv *itv, unsigned idx)
diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c
index 3ce7c64e5789..8ee1179be926 100644
--- a/drivers/media/video/v4l2-common.c
+++ b/drivers/media/video/v4l2-common.c
@@ -381,7 +381,8 @@ struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
 
         /* Create the i2c client */
         if (info->addr == 0 && probe_addrs)
-                client = i2c_new_probed_device(adapter, info, probe_addrs);
+                client = i2c_new_probed_device(adapter, info, probe_addrs,
+                                               NULL);
         else
                 client = i2c_new_device(adapter, info);
 
diff --git a/drivers/usb/host/ohci-pnx4008.c b/drivers/usb/host/ohci-pnx4008.c
index cd74bbdd007c..653d6a60edb5 100644
--- a/drivers/usb/host/ohci-pnx4008.c
+++ b/drivers/usb/host/ohci-pnx4008.c
@@ -329,7 +329,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
         memset(&i2c_info, 0, sizeof(struct i2c_board_info));
         strlcpy(i2c_info.type, "isp1301_pnx", I2C_NAME_SIZE);
         isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info,
-                                                   normal_i2c);
+                                                   normal_i2c, NULL);
         i2c_put_adapter(i2c_adap);
         if (!isp1301_i2c_client) {
                 err("failed to connect I2C to ISP1301 USB Transceiver");
diff --git a/drivers/video/matrox/i2c-matroxfb.c b/drivers/video/matrox/i2c-matroxfb.c
index 403b14445a78..0fb280ead3dc 100644
--- a/drivers/video/matrox/i2c-matroxfb.c
+++ b/drivers/video/matrox/i2c-matroxfb.c
@@ -191,7 +191,7 @@ static void* i2c_matroxfb_probe(struct matrox_fb_info* minfo) {
                         };
 
                         i2c_new_probed_device(&m2info->maven.adapter,
-                                              &maven_info, addr_list);
+                                              &maven_info, addr_list, NULL);
                 }
         }
         return m2info;
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 38dd4025aa4e..59a9f3cdc0b5 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -284,12 +284,15 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
 
 /* If you don't know the exact address of an I2C device, use this variant
  * instead, which can probe for device presence in a list of possible
- * addresses.
+ * addresses. The "probe" callback function is optional. If it is provided,
+ * it must return 1 on successful probe, 0 otherwise. If it is not provided,
+ * a default probing method is used.
  */
 extern struct i2c_client *
 i2c_new_probed_device(struct i2c_adapter *adap,
                       struct i2c_board_info *info,
-                      unsigned short const *addr_list);
+                      unsigned short const *addr_list,
+                      int (*probe)(struct i2c_adapter *, unsigned short addr));
 
 /* For devices that use several addresses, use i2c_new_dummy() to make
  * client handles for the extra addresses.