drivers/media/i2c/tlv320aic23b.c

Source file repositories/reference/linux-study-clean/drivers/media/i2c/tlv320aic23b.c

File Facts

System
Linux kernel
Corpus path
drivers/media/i2c/tlv320aic23b.c
Extension
.c
Size
5226 bytes
Lines
206
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct tlv320aic23b_state {
	struct v4l2_subdev sd;
	struct v4l2_ctrl_handler hdl;
};

static inline struct tlv320aic23b_state *to_state(struct v4l2_subdev *sd)
{
	return container_of(sd, struct tlv320aic23b_state, sd);
}

static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
{
	return &container_of(ctrl->handler, struct tlv320aic23b_state, hdl)->sd;
}

static int tlv320aic23b_write(struct v4l2_subdev *sd, int reg, u16 val)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int i;

	if ((reg < 0 || reg > 9) && (reg != 15)) {
		v4l2_err(sd, "Invalid register R%d\n", reg);
		return -1;
	}

	for (i = 0; i < 3; i++)
		if (i2c_smbus_write_byte_data(client,
				(reg << 1) | (val >> 8), val & 0xff) == 0)
			return 0;
	v4l2_err(sd, "I2C: cannot write %03x to register R%d\n", val, reg);
	return -1;
}

static int tlv320aic23b_s_clock_freq(struct v4l2_subdev *sd, u32 freq)
{
	switch (freq) {
	case 32000: /* set sample rate to 32 kHz */
		tlv320aic23b_write(sd, 8, 0x018);
		break;
	case 44100: /* set sample rate to 44.1 kHz */
		tlv320aic23b_write(sd, 8, 0x022);
		break;
	case 48000: /* set sample rate to 48 kHz */
		tlv320aic23b_write(sd, 8, 0x000);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static int tlv320aic23b_s_ctrl(struct v4l2_ctrl *ctrl)
{
	struct v4l2_subdev *sd = to_sd(ctrl);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		tlv320aic23b_write(sd, 0, 0x180); /* mute both channels */
		/* set gain on both channels to +3.0 dB */
		if (!ctrl->val)
			tlv320aic23b_write(sd, 0, 0x119);
		return 0;
	}
	return -EINVAL;
}

static int tlv320aic23b_log_status(struct v4l2_subdev *sd)
{
	struct tlv320aic23b_state *state = to_state(sd);

	v4l2_ctrl_handler_log_status(&state->hdl, sd->name);
	return 0;
}

/* ----------------------------------------------------------------------- */

static const struct v4l2_ctrl_ops tlv320aic23b_ctrl_ops = {
	.s_ctrl = tlv320aic23b_s_ctrl,
};

static const struct v4l2_subdev_core_ops tlv320aic23b_core_ops = {
	.log_status = tlv320aic23b_log_status,
};

static const struct v4l2_subdev_audio_ops tlv320aic23b_audio_ops = {
	.s_clock_freq = tlv320aic23b_s_clock_freq,
};

static const struct v4l2_subdev_ops tlv320aic23b_ops = {
	.core = &tlv320aic23b_core_ops,

Annotation

Implementation Notes