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authorHans Verkuil <hverkuil@xs4all.nl>2017-08-31 12:56:10 -0400
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2017-09-23 07:29:30 -0400
commite949f61461ab83b094cad564c89a8d2b078b4508 (patch)
tree9bb255c603c6ccc1f23712494b535710e0245153
parent81b79c71e546fc15e95e804de2497a448cc51a47 (diff)
downloadlinux-e949f61461ab83b094cad564c89a8d2b078b4508.tar.bz2
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: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Cc: <stable@vger.kernel.org> # for v4.12 and up Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
-rw-r--r--drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c3
-rw-r--r--drivers/media/platform/s5p-cec/s5p_cec.c11
-rw-r--r--drivers/media/platform/s5p-cec/s5p_cec.h2
3 files changed, 14 insertions, 2 deletions
diff --git a/drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c b/drivers/media/platform/s5p-cec/exynos_hdmi_cecctrl.c
index 1edf667d562a..146ae6f25cdb 100644
--- 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_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;
diff --git a/drivers/media/platform/s5p-cec/s5p_cec.c b/drivers/media/platform/s5p-cec/s5p_cec.c
index 58d200e7c838..8837e2678bde 100644
--- 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(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,
diff --git a/drivers/media/platform/s5p-cec/s5p_cec.h b/drivers/media/platform/s5p-cec/s5p_cec.h
index 8bcd8dc1aeb9..86ded522ef27 100644
--- 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
};