Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e949f614 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: s5p-cec: add NACK detection support 



The s5p-cec driver returned CEC_TX_STATUS_ERROR for the NACK condition.

Some digging into the datasheet uncovered the S5P_CEC_TX_STAT1 register where
bit 0 indicates if the transmit was nacked or not.

Use this to return the correct CEC_TX_STATUS_NACK status to userspace.

This was the only driver that couldn't tell a NACK from another error, and
that was very unusual. And a potential problem for applications as well.

Tested with my Odroid-U3.

Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Acked-by: default avatarSylwester Nawrocki <s.nawrocki@samsung.com>
Cc: <stable@vger.kernel.org>      # for v4.12 and up
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 81b79c71

drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c

+2 −1
Original line number Diff line number Diff line
@@ -172,7 +172,8 @@ u32 s5p_cec_get_status(struct s5p_cec_dev *cec) 
{

	u32 status = 0;



	status = readb(cec->reg + S5P_CEC_STATUS_0);

	status = readb(cec->reg + S5P_CEC_STATUS_0) & 0xf;

	status |= (readb(cec->reg + S5P_CEC_TX_STAT1) & 0xf) << 4;

	status |= readb(cec->reg + S5P_CEC_STATUS_1) << 8;

	status |= readb(cec->reg + S5P_CEC_STATUS_2) << 16;

	status |= readb(cec->reg + S5P_CEC_STATUS_3) << 24;

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

+10 −1
Original line number Diff line number Diff line
@@ -92,7 +92,10 @@ static irqreturn_t s5p_cec_irq_handler(int irq, void *priv) 
	dev_dbg(cec->dev, "irq received\n");



	if (status & CEC_STATUS_TX_DONE) {

		if (status & CEC_STATUS_TX_ERROR) {

		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 {
@@ -135,6 +138,12 @@ static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv) 
		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,

drivers/media/platform/s5p-cec/s5p_cec.h

+2 −0
Original line number Diff line number Diff line
@@ -35,6 +35,7 @@ 
#define CEC_STATUS_TX_TRANSFERRING	(1 << 1)

#define CEC_STATUS_TX_DONE		(1 << 2)

#define CEC_STATUS_TX_ERROR		(1 << 3)

#define CEC_STATUS_TX_NACK		(1 << 4)

#define CEC_STATUS_TX_BYTES		(0xFF << 8)

#define CEC_STATUS_RX_RUNNING		(1 << 16)

#define CEC_STATUS_RX_RECEIVING		(1 << 17)
@@ -55,6 +56,7 @@ enum cec_state { 
	STATE_IDLE,

	STATE_BUSY,

	STATE_DONE,

	STATE_NACK,

	STATE_ERROR

};