drivers/media/cec/platform/s5p/s5p_cec.c

Source file repositories/reference/linux-study-clean/drivers/media/cec/platform/s5p/s5p_cec.c

File Facts

System
Linux kernel
Corpus path
drivers/media/cec/platform/s5p/s5p_cec.c
Extension
.c
Size
7292 bytes
Lines
310
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

if (status & CEC_STATUS_TX_NACK) {
			dev_dbg(cec->dev, "CEC_STATUS_TX_NACK set\n");
			cec->tx = STATE_NACK;
		} else if (status & CEC_STATUS_TX_ERROR) {
			dev_dbg(cec->dev, "CEC_STATUS_TX_ERROR set\n");
			cec->tx = STATE_ERROR;
		} else {
			dev_dbg(cec->dev, "CEC_STATUS_TX_DONE\n");
			cec->tx = STATE_DONE;
		}
		s5p_clr_pending_tx(cec);
	}

	if (status & CEC_STATUS_RX_DONE) {
		if (status & CEC_STATUS_RX_ERROR) {
			dev_dbg(cec->dev, "CEC_STATUS_RX_ERROR set\n");
			s5p_cec_rx_reset(cec);
			s5p_cec_enable_rx(cec);
		} else {
			dev_dbg(cec->dev, "CEC_STATUS_RX_DONE set\n");
			if (cec->rx != STATE_IDLE)
				dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n");
			cec->rx = STATE_BUSY;
			cec->msg.len = status >> 24;
			if (cec->msg.len > CEC_MAX_MSG_SIZE)
				cec->msg.len = CEC_MAX_MSG_SIZE;
			cec->msg.rx_status = CEC_RX_STATUS_OK;
			s5p_cec_get_rx_buf(cec, cec->msg.len,
					cec->msg.msg);
			cec->rx = STATE_DONE;
			s5p_cec_enable_rx(cec);
		}
		/* Clear interrupt pending bit */
		s5p_clr_pending_rx(cec);
	}
	return IRQ_WAKE_THREAD;
}

static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv)
{
	struct s5p_cec_dev *cec = priv;

	dev_dbg(cec->dev, "irq processing thread\n");
	switch (cec->tx) {
	case STATE_DONE:
		cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0);
		cec->tx = STATE_IDLE;
		break;
	case STATE_NACK:
		cec_transmit_done(cec->adap,
			CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_NACK,
			0, 1, 0, 0);
		cec->tx = STATE_IDLE;
		break;
	case STATE_ERROR:
		cec_transmit_done(cec->adap,
			CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_ERROR,
			0, 0, 0, 1);
		cec->tx = STATE_IDLE;
		break;
	case STATE_BUSY:
		dev_err(cec->dev, "state set to busy, this should not occur here\n");
		break;
	default:
		break;
	}

	switch (cec->rx) {
	case STATE_DONE:
		cec_received_msg(cec->adap, &cec->msg);
		cec->rx = STATE_IDLE;
		break;
	default:
		break;
	}

	return IRQ_HANDLED;
}

static const struct cec_adap_ops s5p_cec_adap_ops = {
	.adap_enable = s5p_cec_adap_enable,
	.adap_log_addr = s5p_cec_adap_log_addr,
	.adap_transmit = s5p_cec_adap_transmit,
};

static int s5p_cec_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device *hdmi_dev;
	struct s5p_cec_dev *cec;

Annotation

Implementation Notes