[linux-block.git] / drivers / media / v4l2-core / v4l2-i2c.c

// 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_unregister(struct v4l2_subdev *sd)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	/*
	 * We need to unregister the i2c client
	 * explicitly. We cannot rely on
	 * i2c_del_adapter to always unregister
	 * clients for us, since if the i2c bus is a
	 * platform bus, then it is never deleted.
	 *
	 * Device tree or ACPI based devices must not
	 * be unregistered as they have not been
	 * registered by us, and would not be
	 * re-created by just probing the V4L2 driver.
	 */
	if (client && !client->dev.of_node && !client->dev.fwnode)
		i2c_unregister_device(client);
}

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);
Commit	Line	Data
02283b98 EG	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/*
	3	* v4l2-i2c - I2C helpers for Video4Linux2
	4	*/
	5
	6	#include <linux/i2c.h>
	7	#include <linux/module.h>
	8	#include <media/v4l2-common.h>
	9	#include <media/v4l2-device.h>
	10
51ff392c EG	11	void v4l2_i2c_subdev_unregister(struct v4l2_subdev *sd)
	12	{
	13	struct i2c_client *client = v4l2_get_subdevdata(sd);
	14
	15	/*
	16	* We need to unregister the i2c client
	17	* explicitly. We cannot rely on
	18	* i2c_del_adapter to always unregister
	19	* clients for us, since if the i2c bus is a
	20	* platform bus, then it is never deleted.
	21	*
	22	* Device tree or ACPI based devices must not
	23	* be unregistered as they have not been
	24	* registered by us, and would not be
	25	* re-created by just probing the V4L2 driver.
	26	*/
	27	if (client && !client->dev.of_node && !client->dev.fwnode)
	28	i2c_unregister_device(client);
	29	}
	30
02283b98 EG	31	void v4l2_i2c_subdev_set_name(struct v4l2_subdev sd, struct i2c_client client,
	32	const char devname, const char postfix)
	33	{
	34	if (!devname)
	35	devname = client->dev.driver->name;
	36	if (!postfix)
	37	postfix = "";
	38
	39	snprintf(sd->name, sizeof(sd->name), "%s%s %d-%04x", devname, postfix,
	40	i2c_adapter_id(client->adapter), client->addr);
	41	}
	42	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_set_name);
	43
	44	void v4l2_i2c_subdev_init(struct v4l2_subdev sd, struct i2c_client client,
	45	const struct v4l2_subdev_ops *ops)
	46	{
	47	v4l2_subdev_init(sd, ops);
	48	sd->flags \|= V4L2_SUBDEV_FL_IS_I2C;
	49	/* the owner is the same as the i2c_client's driver owner */
	50	sd->owner = client->dev.driver->owner;
	51	sd->dev = &client->dev;
	52	/* i2c_client and v4l2_subdev point to one another */
	53	v4l2_set_subdevdata(sd, client);
	54	i2c_set_clientdata(client, sd);
	55	v4l2_i2c_subdev_set_name(sd, client, NULL, NULL);
	56	}
	57	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
	58
	59	/* Load an i2c sub-device. */
	60	struct v4l2_subdev v4l2_i2c_new_subdev_board(struct v4l2_device v4l2_dev,
	61	struct i2c_adapter adapter, struct i2c_board_info info,
	62	const unsigned short *probe_addrs)
	63	{
	64	struct v4l2_subdev *sd = NULL;
	65	struct i2c_client *client;
	66
	67	BUG_ON(!v4l2_dev);
	68
	69	request_module(I2C_MODULE_PREFIX "%s", info->type);
	70
	71	/* Create the i2c client */
	72	if (info->addr == 0 && probe_addrs)
	73	client = i2c_new_probed_device(adapter, info, probe_addrs,
	74	NULL);
	75	else
	76	client = i2c_new_device(adapter, info);
	77
	78	/* Note: by loading the module first we are certain that c->driver
	79	will be set if the driver was found. If the module was not loaded
	80	first, then the i2c core tries to delay-load the module for us,
	81	and then c->driver is still NULL until the module is finally
	82	loaded. This delay-load mechanism doesn't work if other drivers
	83	want to use the i2c device, so explicitly loading the module
	84	is the best alternative. */
	85	if (client == NULL \|\| client->dev.driver == NULL)
	86	goto error;
	87
	88	/* Lock the module so we can safely get the v4l2_subdev pointer */
	89	if (!try_module_get(client->dev.driver->owner))
	90	goto error;
	91	sd = i2c_get_clientdata(client);
	92
	93	/* Register with the v4l2_device which increases the module's
	94	use count as well. */
95	if (v4l2_device_register_subdev(v4l2_dev, sd))
96	sd = NULL;
97	/* Decrease the module use count to match the first try_module_get. */
98	module_put(client->dev.driver->owner);
99
100	error:
101	/* If we have a client but no subdev, then something went wrong and
102	we must unregister the client. */
103	if (client && sd == NULL)
104	i2c_unregister_device(client);
105	return sd;
106	}
107	EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
108
109	struct v4l2_subdev v4l2_i2c_new_subdev(struct v4l2_device v4l2_dev,
110	struct i2c_adapter adapter, const char client_type,
111	u8 addr, const unsigned short *probe_addrs)
112	{
113	struct i2c_board_info info;
114
115	/* Setup the i2c board info with the device type and
116	the device address. */
117	memset(&info, 0, sizeof(info));
118	strscpy(info.type, client_type, sizeof(info.type));
119	info.addr = addr;
120
121	return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
122	}
123	EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
124
125	/* Return i2c client address of v4l2_subdev. */
126	unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
127	{
128	struct i2c_client *client = v4l2_get_subdevdata(sd);
129
130	return client ? client->addr : I2C_CLIENT_END;
131	}
132	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
133
134	/* Return a list of I2C tuner addresses to probe. Use only if the tuner
135	addresses are unknown. */
136	const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
137	{
138	static const unsigned short radio_addrs[] = {
139	#if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761)
140	0x10,
141	#endif
142	0x60,
143	I2C_CLIENT_END
144	};
145	static const unsigned short demod_addrs[] = {
146	0x42, 0x43, 0x4a, 0x4b,
147	I2C_CLIENT_END
148	};
149	static const unsigned short tv_addrs[] = {
150	0x42, 0x43, 0x4a, 0x4b, /* tda8290 */
151	0x60, 0x61, 0x62, 0x63, 0x64,
152	I2C_CLIENT_END
153	};
154
155	switch (type) {
156	case ADDRS_RADIO:
157	return radio_addrs;
158	case ADDRS_DEMOD:
159	return demod_addrs;
160	case ADDRS_TV:
161	return tv_addrs;
162	case ADDRS_TV_WITH_DEMOD:
163	return tv_addrs + 4;
164	}
165	return NULL;
166	}
167	EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);