[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_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
	11	void v4l2_i2c_subdev_set_name(struct v4l2_subdev sd, struct i2c_client client,
	12	const char devname, const char postfix)
	13	{
	14	if (!devname)
	15	devname = client->dev.driver->name;
	16	if (!postfix)
	17	postfix = "";
	18
	19	snprintf(sd->name, sizeof(sd->name), "%s%s %d-%04x", devname, postfix,
	20	i2c_adapter_id(client->adapter), client->addr);
	21	}
	22	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_set_name);
	23
	24	void v4l2_i2c_subdev_init(struct v4l2_subdev sd, struct i2c_client client,
	25	const struct v4l2_subdev_ops *ops)
	26	{
	27	v4l2_subdev_init(sd, ops);
	28	sd->flags \|= V4L2_SUBDEV_FL_IS_I2C;
	29	/* the owner is the same as the i2c_client's driver owner */
	30	sd->owner = client->dev.driver->owner;
	31	sd->dev = &client->dev;
	32	/* i2c_client and v4l2_subdev point to one another */
	33	v4l2_set_subdevdata(sd, client);
	34	i2c_set_clientdata(client, sd);
	35	v4l2_i2c_subdev_set_name(sd, client, NULL, NULL);
	36	}
	37	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
	38
	39	/* Load an i2c sub-device. */
	40	struct v4l2_subdev v4l2_i2c_new_subdev_board(struct v4l2_device v4l2_dev,
	41	struct i2c_adapter adapter, struct i2c_board_info info,
	42	const unsigned short *probe_addrs)
	43	{
	44	struct v4l2_subdev *sd = NULL;
	45	struct i2c_client *client;
	46
	47	BUG_ON(!v4l2_dev);
	48
	49	request_module(I2C_MODULE_PREFIX "%s", info->type);
	50
	51	/* Create the i2c client */
	52	if (info->addr == 0 && probe_addrs)
	53	client = i2c_new_probed_device(adapter, info, probe_addrs,
	54	NULL);
	55	else
	56	client = i2c_new_device(adapter, info);
	57
	58	/* Note: by loading the module first we are certain that c->driver
	59	will be set if the driver was found. If the module was not loaded
	60	first, then the i2c core tries to delay-load the module for us,
	61	and then c->driver is still NULL until the module is finally
	62	loaded. This delay-load mechanism doesn't work if other drivers
	63	want to use the i2c device, so explicitly loading the module
	64	is the best alternative. */
65	if (client == NULL \|\| client->dev.driver == NULL)
66	goto error;
67
68	/* Lock the module so we can safely get the v4l2_subdev pointer */
69	if (!try_module_get(client->dev.driver->owner))
70	goto error;
71	sd = i2c_get_clientdata(client);
72
73	/* Register with the v4l2_device which increases the module's
74	use count as well. */
75	if (v4l2_device_register_subdev(v4l2_dev, sd))
76	sd = NULL;
77	/* Decrease the module use count to match the first try_module_get. */
78	module_put(client->dev.driver->owner);
79
80	error:
81	/* If we have a client but no subdev, then something went wrong and
82	we must unregister the client. */
83	if (client && sd == NULL)
84	i2c_unregister_device(client);
85	return sd;
86	}
87	EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
88
89	struct v4l2_subdev v4l2_i2c_new_subdev(struct v4l2_device v4l2_dev,
90	struct i2c_adapter adapter, const char client_type,
91	u8 addr, const unsigned short *probe_addrs)
92	{
93	struct i2c_board_info info;
94
95	/* Setup the i2c board info with the device type and
96	the device address. */
97	memset(&info, 0, sizeof(info));
98	strscpy(info.type, client_type, sizeof(info.type));
99	info.addr = addr;
100
101	return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
102	}
103	EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
104
105	/* Return i2c client address of v4l2_subdev. */
106	unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
107	{
108	struct i2c_client *client = v4l2_get_subdevdata(sd);
109
110	return client ? client->addr : I2C_CLIENT_END;
111	}
112	EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
113
114	/* Return a list of I2C tuner addresses to probe. Use only if the tuner
115	addresses are unknown. */
116	const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
117	{
118	static const unsigned short radio_addrs[] = {
119	#if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761)
120	0x10,
121	#endif
122	0x60,
123	I2C_CLIENT_END
124	};
125	static const unsigned short demod_addrs[] = {
126	0x42, 0x43, 0x4a, 0x4b,
127	I2C_CLIENT_END
128	};
129	static const unsigned short tv_addrs[] = {
130	0x42, 0x43, 0x4a, 0x4b, /* tda8290 */
131	0x60, 0x61, 0x62, 0x63, 0x64,
132	I2C_CLIENT_END
133	};
134
135	switch (type) {
136	case ADDRS_RADIO:
137	return radio_addrs;
138	case ADDRS_DEMOD:
139	return demod_addrs;
140	case ADDRS_TV:
141	return tv_addrs;
142	case ADDRS_TV_WITH_DEMOD:
143	return tv_addrs + 4;
144	}
145	return NULL;
146	}
147	EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);