media: v4l2-core: move i2c helpers out of v4l2-common.c

Separate the i2c helpers to v4l2-i2c.c, in order to get rid
of the ifdefery. No functional changes intended, this is
just a cosmetic change to organize the code better.

Given I2C is a tristate symbol, a hidden boolean symbol
is introduced, to make the conditional build easier.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

5 files changed, 229 insertions, 182 deletions

diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index 7c5f62f196e5..39e3fb30ba0b 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -11,6 +11,11 @@ config VIDEO_V4L2
         select VIDEOBUF2_V4L2 if VIDEOBUF2_CORE
         default (I2C || I2C=n) && VIDEO_DEV
 
+config VIDEO_V4L2_I2C
+        bool
+        depends on I2C && VIDEO_V4L2
+        default y
+
 config VIDEO_ADV_DEBUG
         bool "Enable advanced debug functionality on V4L2 drivers"
         help
diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile
index 2deeeac6ee76..786bd1ec4d1b 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -12,6 +12,7 @@ videodev-$(CONFIG_COMPAT) += v4l2-compat-ioctl32.o
 videodev-$(CONFIG_TRACEPOINTS) += v4l2-trace.o
 videodev-$(CONFIG_MEDIA_CONTROLLER) += v4l2-mc.o
 videodev-$(CONFIG_SPI) += v4l2-spi.o
+videodev-$(CONFIG_VIDEO_V4L2_I2C) += v4l2-i2c.o
 
 obj-$(CONFIG_V4L2_FWNODE) += v4l2-fwnode.o
 obj-$(CONFIG_VIDEO_V4L2) += videodev.o
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index 8ffa758d9342..62f7aa92ac29 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -40,7 +40,6 @@
 #include <linux/mm.h>
 #include <linux/string.h>
 #include <linux/errno.h>
-#include <linux/i2c.h>
 #include <linux/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/io.h>
@@ -88,150 +87,6 @@ int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 _min, s32 _max, s32 _
 }
 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
 
-/* I2C Helper functions */
-
-#if IS_ENABLED(CONFIG_I2C)
-
-void v4l2_i2c_subdev_set_name(struct v4l2_subdev *sd, struct i2c_client *client,
-                              const char *devname, const char *postfix)
-{
-        if (!devname)
-                devname = client->dev.driver->name;
-        if (!postfix)
-                postfix = "";
-
-        snprintf(sd->name, sizeof(sd->name), "%s%s %d-%04x", devname, postfix,
-                 i2c_adapter_id(client->adapter), client->addr);
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_set_name);
-
-void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
-                const struct v4l2_subdev_ops *ops)
-{
-        v4l2_subdev_init(sd, ops);
-        sd->flags |= V4L2_SUBDEV_FL_IS_I2C;
-        /* the owner is the same as the i2c_client's driver owner */
-        sd->owner = client->dev.driver->owner;
-        sd->dev = &client->dev;
-        /* i2c_client and v4l2_subdev point to one another */
-        v4l2_set_subdevdata(sd, client);
-        i2c_set_clientdata(client, sd);
-        v4l2_i2c_subdev_set_name(sd, client, NULL, NULL);
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
-
-/* Load an i2c sub-device. */
-struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
-                struct i2c_adapter *adapter, struct i2c_board_info *info,
-                const unsigned short *probe_addrs)
-{
-        struct v4l2_subdev *sd = NULL;
-        struct i2c_client *client;
-
-        BUG_ON(!v4l2_dev);
-
-        request_module(I2C_MODULE_PREFIX "%s", info->type);
-
-        /* Create the i2c client */
-        if (info->addr == 0 && probe_addrs)
-                client = i2c_new_probed_device(adapter, info, probe_addrs,
-                                               NULL);
-        else
-                client = i2c_new_device(adapter, info);
-
-        /* Note: by loading the module first we are certain that c->driver
-           will be set if the driver was found. If the module was not loaded
-           first, then the i2c core tries to delay-load the module for us,
-           and then c->driver is still NULL until the module is finally
-           loaded. This delay-load mechanism doesn't work if other drivers
-           want to use the i2c device, so explicitly loading the module
-           is the best alternative. */
-        if (client == NULL || client->dev.driver == NULL)
-                goto error;
-
-        /* Lock the module so we can safely get the v4l2_subdev pointer */
-        if (!try_module_get(client->dev.driver->owner))
-                goto error;
-        sd = i2c_get_clientdata(client);
-
-        /* Register with the v4l2_device which increases the module's
-           use count as well. */
-        if (v4l2_device_register_subdev(v4l2_dev, sd))
-                sd = NULL;
-        /* Decrease the module use count to match the first try_module_get. */
-        module_put(client->dev.driver->owner);
-
-error:
-        /* If we have a client but no subdev, then something went wrong and
-           we must unregister the client. */
-        if (client && sd == NULL)
-                i2c_unregister_device(client);
-        return sd;
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
-
-struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
-                struct i2c_adapter *adapter, const char *client_type,
-                u8 addr, const unsigned short *probe_addrs)
-{
-        struct i2c_board_info info;
-
-        /* Setup the i2c board info with the device type and
-           the device address. */
-        memset(&info, 0, sizeof(info));
-        strscpy(info.type, client_type, sizeof(info.type));
-        info.addr = addr;
-
-        return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
-
-/* Return i2c client address of v4l2_subdev. */
-unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
-{
-        struct i2c_client *client = v4l2_get_subdevdata(sd);
-
-        return client ? client->addr : I2C_CLIENT_END;
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
-
-/* Return a list of I2C tuner addresses to probe. Use only if the tuner
-   addresses are unknown. */
-const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
-{
-        static const unsigned short radio_addrs[] = {
-#if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761)
-                0x10,
-#endif
-                0x60,
-                I2C_CLIENT_END
-        };
-        static const unsigned short demod_addrs[] = {
-                0x42, 0x43, 0x4a, 0x4b,
-                I2C_CLIENT_END
-        };
-        static const unsigned short tv_addrs[] = {
-                0x42, 0x43, 0x4a, 0x4b,         /* tda8290 */
-                0x60, 0x61, 0x62, 0x63, 0x64,
-                I2C_CLIENT_END
-        };
-
-        switch (type) {
-        case ADDRS_RADIO:
-                return radio_addrs;
-        case ADDRS_DEMOD:
-                return demod_addrs;
-        case ADDRS_TV:
-                return tv_addrs;
-        case ADDRS_TV_WITH_DEMOD:
-                return tv_addrs + 4;
-        }
-        return NULL;
-}
-EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);
-
-#endif /* defined(CONFIG_I2C) */
-
 /* Clamp x to be between min and max, aligned to a multiple of 2^align.  min
  * and max don't have to be aligned, but there must be at least one valid
  * value.  E.g., min=17,max=31,align=4 is not allowed as there are no multiples
diff --git a/drivers/media/v4l2-core/v4l2-i2c.c b/drivers/media/v4l2-core/v4l2-i2c.c
new file mode 100644
index 000000000000..f393dd4f1c00
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-i2c.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * v4l2-i2c - I2C helpers for Video4Linux2
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-device.h>
+
+void v4l2_i2c_subdev_set_name(struct v4l2_subdev *sd, struct i2c_client *client,
+                              const char *devname, const char *postfix)
+{
+        if (!devname)
+                devname = client->dev.driver->name;
+        if (!postfix)
+                postfix = "";
+
+        snprintf(sd->name, sizeof(sd->name), "%s%s %d-%04x", devname, postfix,
+                 i2c_adapter_id(client->adapter), client->addr);
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_set_name);
+
+void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
+                const struct v4l2_subdev_ops *ops)
+{
+        v4l2_subdev_init(sd, ops);
+        sd->flags |= V4L2_SUBDEV_FL_IS_I2C;
+        /* the owner is the same as the i2c_client's driver owner */
+        sd->owner = client->dev.driver->owner;
+        sd->dev = &client->dev;
+        /* i2c_client and v4l2_subdev point to one another */
+        v4l2_set_subdevdata(sd, client);
+        i2c_set_clientdata(client, sd);
+        v4l2_i2c_subdev_set_name(sd, client, NULL, NULL);
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
+
+/* Load an i2c sub-device. */
+struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter, struct i2c_board_info *info,
+                const unsigned short *probe_addrs)
+{
+        struct v4l2_subdev *sd = NULL;
+        struct i2c_client *client;
+
+        BUG_ON(!v4l2_dev);
+
+        request_module(I2C_MODULE_PREFIX "%s", info->type);
+
+        /* Create the i2c client */
+        if (info->addr == 0 && probe_addrs)
+                client = i2c_new_probed_device(adapter, info, probe_addrs,
+                                               NULL);
+        else
+                client = i2c_new_device(adapter, info);
+
+        /* Note: by loading the module first we are certain that c->driver
+           will be set if the driver was found. If the module was not loaded
+           first, then the i2c core tries to delay-load the module for us,
+           and then c->driver is still NULL until the module is finally
+           loaded. This delay-load mechanism doesn't work if other drivers
+           want to use the i2c device, so explicitly loading the module
+           is the best alternative. */
+        if (client == NULL || client->dev.driver == NULL)
+                goto error;
+
+        /* Lock the module so we can safely get the v4l2_subdev pointer */
+        if (!try_module_get(client->dev.driver->owner))
+                goto error;
+        sd = i2c_get_clientdata(client);
+
+        /* Register with the v4l2_device which increases the module's
+           use count as well. */
+        if (v4l2_device_register_subdev(v4l2_dev, sd))
+                sd = NULL;
+        /* Decrease the module use count to match the first try_module_get. */
+        module_put(client->dev.driver->owner);
+
+error:
+        /* If we have a client but no subdev, then something went wrong and
+           we must unregister the client. */
+        if (client && sd == NULL)
+                i2c_unregister_device(client);
+        return sd;
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
+
+struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter, const char *client_type,
+                u8 addr, const unsigned short *probe_addrs)
+{
+        struct i2c_board_info info;
+
+        /* Setup the i2c board info with the device type and
+           the device address. */
+        memset(&info, 0, sizeof(info));
+        strscpy(info.type, client_type, sizeof(info.type));
+        info.addr = addr;
+
+        return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
+
+/* Return i2c client address of v4l2_subdev. */
+unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
+{
+        struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+        return client ? client->addr : I2C_CLIENT_END;
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
+
+/* Return a list of I2C tuner addresses to probe. Use only if the tuner
+   addresses are unknown. */
+const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
+{
+        static const unsigned short radio_addrs[] = {
+#if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761)
+                0x10,
+#endif
+                0x60,
+                I2C_CLIENT_END
+        };
+        static const unsigned short demod_addrs[] = {
+                0x42, 0x43, 0x4a, 0x4b,
+                I2C_CLIENT_END
+        };
+        static const unsigned short tv_addrs[] = {
+                0x42, 0x43, 0x4a, 0x4b,         /* tda8290 */
+                0x60, 0x61, 0x62, 0x63, 0x64,
+                I2C_CLIENT_END
+        };
+
+        switch (type) {
+        case ADDRS_RADIO:
+                return radio_addrs;
+        case ADDRS_DEMOD:
+                return demod_addrs;
+        case ADDRS_TV:
+                return tv_addrs;
+        case ADDRS_TV_WITH_DEMOD:
+                return tv_addrs + 4;
+        }
+        return NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index a1c5288caa6a..8e66edddd37b 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -96,16 +96,45 @@ int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl,
 
 /* ------------------------------------------------------------------------- */
 
-/* I2C Helper functions */
-
-struct i2c_driver;
-struct i2c_adapter;
-struct i2c_client;
-struct i2c_device_id;
 struct v4l2_device;
 struct v4l2_subdev;
 struct v4l2_subdev_ops;
 
+/* I2C Helper functions */
+#include <linux/i2c.h>
+
+/**
+ * enum v4l2_i2c_tuner_type - specifies the range of tuner address that
+ *      should be used when seeking for I2C devices.
+ *
+ * @ADDRS_RADIO:                Radio tuner addresses.
+ *                              Represent the following I2C addresses:
+ *                              0x10 (if compiled with tea5761 support)
+ *                              and 0x60.
+ * @ADDRS_DEMOD:                Demod tuner addresses.
+ *                              Represent the following I2C addresses:
+ *                              0x42, 0x43, 0x4a and 0x4b.
+ * @ADDRS_TV:                   TV tuner addresses.
+ *                              Represent the following I2C addresses:
+ *                              0x42, 0x43, 0x4a, 0x4b, 0x60, 0x61, 0x62,
+ *                              0x63 and 0x64.
+ * @ADDRS_TV_WITH_DEMOD:        TV tuner addresses if demod is present, this
+ *                              excludes addresses used by the demodulator
+ *                              from the list of candidates.
+ *                              Represent the following I2C addresses:
+ *                              0x60, 0x61, 0x62, 0x63 and 0x64.
+ *
+ * NOTE: All I2C addresses above use the 7-bit notation.
+ */
+enum v4l2_i2c_tuner_type {
+        ADDRS_RADIO,
+        ADDRS_DEMOD,
+        ADDRS_TV,
+        ADDRS_TV_WITH_DEMOD,
+};
+
+#if defined(CONFIG_VIDEO_V4L2_I2C)
+
 /**
  * v4l2_i2c_new_subdev - Load an i2c module and return an initialized
  *      &struct v4l2_subdev.
@@ -123,8 +152,6 @@ struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
                 struct i2c_adapter *adapter, const char *client_type,
                 u8 addr, const unsigned short *probe_addrs);
 
-struct i2c_board_info;
-
 /**
  * v4l2_i2c_new_subdev_board - Load an i2c module and return an initialized
  *      &struct v4l2_subdev.
@@ -175,35 +202,6 @@ void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
 unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd);
 
 /**
- * enum v4l2_i2c_tuner_type - specifies the range of tuner address that
- *      should be used when seeking for I2C devices.
- *
- * @ADDRS_RADIO:                Radio tuner addresses.
- *                              Represent the following I2C addresses:
- *                              0x10 (if compiled with tea5761 support)
- *                              and 0x60.
- * @ADDRS_DEMOD:                Demod tuner addresses.
- *                              Represent the following I2C addresses:
- *                              0x42, 0x43, 0x4a and 0x4b.
- * @ADDRS_TV:                   TV tuner addresses.
- *                              Represent the following I2C addresses:
- *                              0x42, 0x43, 0x4a, 0x4b, 0x60, 0x61, 0x62,
- *                              0x63 and 0x64.
- * @ADDRS_TV_WITH_DEMOD:        TV tuner addresses if demod is present, this
- *                              excludes addresses used by the demodulator
- *                              from the list of candidates.
- *                              Represent the following I2C addresses:
- *                              0x60, 0x61, 0x62, 0x63 and 0x64.
- *
- * NOTE: All I2C addresses above use the 7-bit notation.
- */
-enum v4l2_i2c_tuner_type {
-        ADDRS_RADIO,
-        ADDRS_DEMOD,
-        ADDRS_TV,
-        ADDRS_TV_WITH_DEMOD,
-};
-/**
  * v4l2_i2c_tuner_addrs - Return a list of I2C tuner addresses to probe.
  *
  * @type: type of the tuner to seek, as defined by
@@ -213,6 +211,47 @@ enum v4l2_i2c_tuner_type {
  */
 const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type);
 
+#else
+
+static inline struct v4l2_subdev *
+v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
+                    struct i2c_adapter *adapter, const char *client_type,
+                    u8 addr, const unsigned short *probe_addrs)
+{
+        return NULL;
+}
+
+static inline struct v4l2_subdev *
+v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
+                          struct i2c_adapter *adapter, struct i2c_board_info *info,
+                          const unsigned short *probe_addrs)
+{
+        return NULL;
+}
+
+static inline void
+v4l2_i2c_subdev_set_name(struct v4l2_subdev *sd, struct i2c_client *client,
+                         const char *devname, const char *postfix)
+{}
+
+static inline void
+v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
+                     const struct v4l2_subdev_ops *ops)
+{}
+
+static inline unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
+{
+        return I2C_CLIENT_END;
+}
+
+static inline const unsigned short *
+v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
+{
+        return NULL;
+}
+
+#endif
+
 /* ------------------------------------------------------------------------- */
 
 /* SPI Helper functions */