3 files changed, 110 insertions, 16 deletions

diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
new file mode 100644
index 000000000000..34536effd652
--- /dev/null
+++ b/include/linux/i2c-mux.h
@@ -0,0 +1,46 @@
+/*
+ *
+ * i2c-mux.h - functions for the i2c-bus mux support
+ *
+ * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
+ * Michael Lawnick <michael.lawnick.ext@nsn.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _LINUX_I2C_MUX_H
+#define _LINUX_I2C_MUX_H
+
+#ifdef __KERNEL__
+
+/*
+ * Called to create a i2c bus on a multiplexed bus segment.
+ * The mux_dev and chan_id parameters are passed to the select
+ * and deselect callback functions to perform hardware-specific
+ * mux control.
+ */
+struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
+                                void *mux_dev, u32 force_nr, u32 chan_id,
+                                int (*select) (struct i2c_adapter *,
+                                               void *mux_dev, u32 chan_id),
+                                int (*deselect) (struct i2c_adapter *,
+                                                 void *mux_dev, u32 chan_id));
+
+int i2c_del_mux_adapter(struct i2c_adapter *adap);
+
+#endif /* __KERNEL__ */
+
+#endif /* _LINUX_I2C_MUX_H */
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 38dd4025aa4e..4bae0b72ed3c 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -37,6 +37,7 @@
 #include <linux/of.h>           /* for struct device_node */
 
 extern struct bus_type i2c_bus_type;
+extern struct device_type i2c_adapter_type;
 
 /* --- General options ------------------------------------------------ */
 
@@ -284,12 +285,18 @@ 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));
+
+/* Common custom probe functions */
+extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
 
 /* For devices that use several addresses, use i2c_new_dummy() to make
  * client handles for the extra addresses.
@@ -362,6 +369,7 @@ struct i2c_adapter {
         char name[48];
         struct completion dev_released;
 
+        struct mutex userspace_clients_lock;
         struct list_head userspace_clients;
 };
 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
@@ -376,23 +384,16 @@ static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
         dev_set_drvdata(&dev->dev, data);
 }
 
-/**
- * i2c_lock_adapter - Prevent access to an I2C bus segment
- * @adapter: Target I2C bus segment
- */
-static inline void i2c_lock_adapter(struct i2c_adapter *adapter)
+static inline int i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
 {
-        rt_mutex_lock(&adapter->bus_lock);
+        return adapter->dev.parent != NULL
+                && adapter->dev.parent->bus == &i2c_bus_type
+                && adapter->dev.parent->type == &i2c_adapter_type;
 }
 
-/**
- * i2c_unlock_adapter - Reauthorize access to an I2C bus segment
- * @adapter: Target I2C bus segment
- */
-static inline void i2c_unlock_adapter(struct i2c_adapter *adapter)
-{
-        rt_mutex_unlock(&adapter->bus_lock);
-}
+/* Adapter locking functions, exported for shared pin cases */
+void i2c_lock_adapter(struct i2c_adapter *);
+void i2c_unlock_adapter(struct i2c_adapter *);
 
 /*flags for the client struct: */
 #define I2C_CLIENT_PEC  0x04            /* Use Packet Error Checking */
diff --git a/include/linux/i2c/pca954x.h b/include/linux/i2c/pca954x.h
new file mode 100644
index 000000000000..28f1f8d5ab1f
--- /dev/null
+++ b/include/linux/i2c/pca954x.h
@@ -0,0 +1,47 @@
+/*
+ *
+ * pca954x.h - I2C multiplexer/switch support
+ *
+ * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
+ * Michael Lawnick <michael.lawnick.ext@nsn.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#ifndef _LINUX_I2C_PCA954X_H
+#define _LINUX_I2C_PCA954X_H
+
+/* Platform data for the PCA954x I2C multiplexers */
+
+/* Per channel initialisation data:
+ * @adap_id: bus number for the adapter. 0 = don't care
+ * @deselect_on_exit: set this entry to 1, if your H/W needs deselection
+ *                    of this channel after transaction.
+ *
+ */
+struct pca954x_platform_mode {
+        int             adap_id;
+        unsigned int    deselect_on_exit:1;
+};
+
+/* Per mux/switch data, used with i2c_register_board_info */
+struct pca954x_platform_data {
+        struct pca954x_platform_mode *modes;
+        int num_modes;
+};
+
+#endif /* _LINUX_I2C_PCA954X_H */