This is a note to let you know that I've just added the patch titled
media: s5p-cec: add NACK detection support
to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
media-s5p-cec-add-nack-detection-support.patch
and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e949f61461ab83b094cad564c89a8d2b078b4508 Mon Sep 17 00:00:00 2001
From: Hans Verkuil <hverkuil@xxxxxxxxx>
Date: Thu, 31 Aug 2017 12:56:10 -0400
Subject: media: s5p-cec: add NACK detection support
From: Hans Verkuil <hverkuil@xxxxxxxxx>
commit e949f61461ab83b094cad564c89a8d2b078b4508 upstream.
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: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Acked-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c | 3 ++-
drivers/media/platform/s5p-cec/s5p_cec.c | 11 ++++++++++-
drivers/media/platform/s5p-cec/s5p_cec.h | 2 ++
3 files changed, 14 insertions(+), 2 deletions(-)
--- a/drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c
+++ b/drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c
@@ -172,7 +172,8 @@ u32 s5p_cec_get_status(struct s5p_cec_de
{
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;
--- a/drivers/media/platform/s5p-cec/s5p_cec.c
+++ b/drivers/media/platform/s5p-cec/s5p_cec.c
@@ -92,7 +92,10 @@ static irqreturn_t s5p_cec_irq_handler(i
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_t
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,
--- a/drivers/media/platform/s5p-cec/s5p_cec.h
+++ b/drivers/media/platform/s5p-cec/s5p_cec.h
@@ -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
};
Patches currently in stable-queue which might be from hverkuil@xxxxxxxxx are
queue-4.13/media-s5p-cec-add-nack-detection-support.patch