[PATCH 4/4] drm/vc4: add HDMI CEC support
Hans Verkuil
hverkuil at xs4all.nl
Tue Jul 11 11:20:21 UTC 2017
From: Hans Verkuil <hans.verkuil at cisco.com>
This patch adds support to VC4 for CEC.
To prevent the firmware from eating the CEC interrupts you need to add this to
your config.txt:
mask_gpu_interrupt1=0x100
Signed-off-by: Hans Verkuil <hans.verkuil at cisco.com>
---
drivers/gpu/drm/vc4/Kconfig | 8 ++
drivers/gpu/drm/vc4/vc4_hdmi.c | 203 ++++++++++++++++++++++++++++++++++++++++-
drivers/gpu/drm/vc4/vc4_regs.h | 5 +
3 files changed, 211 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/vc4/Kconfig b/drivers/gpu/drm/vc4/Kconfig
index 4361bdcfd28a..fdae18aeab4f 100644
--- a/drivers/gpu/drm/vc4/Kconfig
+++ b/drivers/gpu/drm/vc4/Kconfig
@@ -19,3 +19,11 @@ config DRM_VC4
This driver requires that "avoid_warnings=2" be present in
the config.txt for the firmware, to keep it from smashing
our display setup.
+
+config DRM_VC4_HDMI_CEC
+ bool "Broadcom VC4 HDMI CEC Support"
+ depends on DRM_VC4
+ select CEC_CORE
+ help
+ Choose this option if you have a Broadcom VC4 GPU
+ and want to use CEC.
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index b0521e6cc281..14e2ece5db94 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -57,6 +57,7 @@
#include <sound/pcm_drm_eld.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
+#include "media/cec.h"
#include "vc4_drv.h"
#include "vc4_regs.h"
@@ -85,6 +86,11 @@ struct vc4_hdmi {
int hpd_gpio;
bool hpd_active_low;
+ struct cec_adapter *cec_adap;
+ struct cec_msg cec_rx_msg;
+ bool cec_tx_ok;
+ bool cec_irq_was_rx;
+
struct clk *pixel_clock;
struct clk *hsm_clock;
};
@@ -156,6 +162,7 @@ static const struct {
HDMI_REG(VC4_HDMI_CEC_CNTRL_4),
HDMI_REG(VC4_HDMI_CEC_CNTRL_5),
HDMI_REG(VC4_HDMI_CPU_STATUS),
+ HDMI_REG(VC4_HDMI_CPU_MASK_STATUS),
HDMI_REG(VC4_HDMI_CEC_RX_DATA_1),
HDMI_REG(VC4_HDMI_CEC_RX_DATA_2),
@@ -232,8 +239,8 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
if (gpio_get_value_cansleep(vc4->hdmi->hpd_gpio) ^
vc4->hdmi->hpd_active_low)
return connector_status_connected;
- else
- return connector_status_disconnected;
+ cec_phys_addr_invalidate(vc4->hdmi->cec_adap);
+ return connector_status_disconnected;
}
if (drm_probe_ddc(vc4->hdmi->ddc))
@@ -241,8 +248,8 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
if (HDMI_READ(VC4_HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
return connector_status_connected;
- else
- return connector_status_disconnected;
+ cec_phys_addr_invalidate(vc4->hdmi->cec_adap);
+ return connector_status_disconnected;
}
static void vc4_hdmi_connector_destroy(struct drm_connector *connector)
@@ -263,6 +270,7 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
struct edid *edid;
edid = drm_get_edid(connector, vc4->hdmi->ddc);
+ cec_s_phys_addr_from_edid(vc4->hdmi->cec_adap, edid);
if (!edid)
return -ENODEV;
@@ -1137,6 +1145,165 @@ static void vc4_hdmi_audio_cleanup(struct vc4_hdmi *hdmi)
snd_soc_unregister_codec(dev);
}
+#ifdef CONFIG_DRM_VC4_HDMI_CEC
+static irqreturn_t vc4_cec_irq_handler_thread(int irq, void *priv)
+{
+ struct vc4_dev *vc4 = priv;
+ struct vc4_hdmi *hdmi = vc4->hdmi;
+
+ if (hdmi->cec_irq_was_rx) {
+ if (hdmi->cec_rx_msg.len)
+ cec_received_msg(hdmi->cec_adap, &hdmi->cec_rx_msg);
+ } else if (hdmi->cec_tx_ok) {
+ cec_transmit_done(hdmi->cec_adap, CEC_TX_STATUS_OK,
+ 0, 0, 0, 0);
+ } else {
+ /*
+ * This CEC implementation makes 1 retry, so if we
+ * get a NACK, then that means it made 2 attempts.
+ */
+ cec_transmit_done(hdmi->cec_adap, CEC_TX_STATUS_NACK,
+ 0, 2, 0, 0);
+ }
+ return IRQ_HANDLED;
+}
+
+static void vc4_cec_read_msg(struct vc4_dev *vc4, u32 cntrl1)
+{
+ struct cec_msg *msg = &vc4->hdmi->cec_rx_msg;
+ unsigned int i;
+
+ msg->len = 1 + ((cntrl1 & VC4_HDMI_CEC_REC_WRD_CNT_MASK) >>
+ VC4_HDMI_CEC_REC_WRD_CNT_SHIFT);
+ for (i = 0; i < msg->len; i += 4) {
+ u32 val = HDMI_READ(VC4_HDMI_CEC_RX_DATA_1 + i);
+
+ msg->msg[i] = val & 0xff;
+ msg->msg[i + 1] = (val >> 8) & 0xff;
+ msg->msg[i + 2] = (val >> 16) & 0xff;
+ msg->msg[i + 3] = (val >> 24) & 0xff;
+ }
+}
+
+static irqreturn_t vc4_cec_irq_handler(int irq, void *priv)
+{
+ struct vc4_dev *vc4 = priv;
+ struct vc4_hdmi *hdmi = vc4->hdmi;
+ u32 stat = HDMI_READ(VC4_HDMI_CPU_STATUS);
+ u32 cntrl1, cntrl5;
+
+ if (!(stat & VC4_HDMI_CPU_CEC))
+ return IRQ_NONE;
+ hdmi->cec_rx_msg.len = 0;
+ cntrl1 = HDMI_READ(VC4_HDMI_CEC_CNTRL_1);
+ cntrl5 = HDMI_READ(VC4_HDMI_CEC_CNTRL_5);
+ hdmi->cec_irq_was_rx = cntrl5 & VC4_HDMI_CEC_RX_CEC_INT;
+ if (hdmi->cec_irq_was_rx) {
+ vc4_cec_read_msg(vc4, cntrl1);
+ cntrl1 |= VC4_HDMI_CEC_CLEAR_RECEIVE_OFF;
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1, cntrl1);
+ cntrl1 &= ~VC4_HDMI_CEC_CLEAR_RECEIVE_OFF;
+ } else {
+ hdmi->cec_tx_ok = cntrl1 & VC4_HDMI_CEC_TX_STATUS_GOOD;
+ cntrl1 &= ~VC4_HDMI_CEC_START_XMIT_BEGIN;
+ }
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1, cntrl1);
+ HDMI_WRITE(VC4_HDMI_CPU_CLEAR, VC4_HDMI_CPU_CEC);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static int vc4_hdmi_cec_adap_enable(struct cec_adapter *adap, bool enable)
+{
+ struct vc4_dev *vc4 = cec_get_drvdata(adap);
+ u32 hsm_clock = clk_get_rate(vc4->hdmi->hsm_clock);
+ u32 cntrl1 = HDMI_READ(VC4_HDMI_CEC_CNTRL_1);
+ u32 divclk = cntrl1 & VC4_HDMI_CEC_DIV_CLK_CNT_MASK;
+ /* clock period in microseconds */
+ u32 usecs = 1000000 / (hsm_clock / divclk);
+ u32 val = HDMI_READ(VC4_HDMI_CEC_CNTRL_5);
+
+ val &= ~(VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET |
+ VC4_HDMI_CEC_CNT_TO_4700_US_MASK |
+ VC4_HDMI_CEC_CNT_TO_4500_US_MASK);
+ val |= ((4700 / usecs) << VC4_HDMI_CEC_CNT_TO_4700_US_SHIFT) |
+ ((4500 / usecs) << VC4_HDMI_CEC_CNT_TO_4500_US_SHIFT);
+
+ if (enable) {
+ cntrl1 &= VC4_HDMI_CEC_DIV_CLK_CNT_MASK |
+ VC4_HDMI_CEC_ADDR_MASK;
+
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_5, val |
+ VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET);
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_5, val);
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_2,
+ ((1500 / usecs) << VC4_HDMI_CEC_CNT_TO_1500_US_SHIFT) |
+ ((1300 / usecs) << VC4_HDMI_CEC_CNT_TO_1300_US_SHIFT) |
+ ((800 / usecs) << VC4_HDMI_CEC_CNT_TO_800_US_SHIFT) |
+ ((600 / usecs) << VC4_HDMI_CEC_CNT_TO_600_US_SHIFT) |
+ ((400 / usecs) << VC4_HDMI_CEC_CNT_TO_400_US_SHIFT));
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_3,
+ ((2750 / usecs) << VC4_HDMI_CEC_CNT_TO_2750_US_SHIFT) |
+ ((2400 / usecs) << VC4_HDMI_CEC_CNT_TO_2400_US_SHIFT) |
+ ((2050 / usecs) << VC4_HDMI_CEC_CNT_TO_2050_US_SHIFT) |
+ ((1700 / usecs) << VC4_HDMI_CEC_CNT_TO_1700_US_SHIFT));
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_4,
+ ((4300 / usecs) << VC4_HDMI_CEC_CNT_TO_4300_US_SHIFT) |
+ ((3900 / usecs) << VC4_HDMI_CEC_CNT_TO_3900_US_SHIFT) |
+ ((3600 / usecs) << VC4_HDMI_CEC_CNT_TO_3600_US_SHIFT) |
+ ((3500 / usecs) << VC4_HDMI_CEC_CNT_TO_3500_US_SHIFT));
+
+ HDMI_WRITE(VC4_HDMI_CPU_MASK_CLEAR, VC4_HDMI_CPU_CEC);
+ } else {
+ HDMI_WRITE(VC4_HDMI_CPU_MASK_SET, VC4_HDMI_CPU_CEC);
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_5, val |
+ VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET);
+ }
+ return 0;
+}
+
+static int vc4_hdmi_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
+{
+ struct vc4_dev *vc4 = cec_get_drvdata(adap);
+
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1,
+ (HDMI_READ(VC4_HDMI_CEC_CNTRL_1) & ~VC4_HDMI_CEC_ADDR_MASK) |
+ (log_addr & 0xf) << VC4_HDMI_CEC_ADDR_SHIFT);
+ return 0;
+}
+
+static int vc4_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time, struct cec_msg *msg)
+{
+ struct vc4_dev *vc4 = cec_get_drvdata(adap);
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < msg->len; i += 4)
+ HDMI_WRITE(VC4_HDMI_CEC_TX_DATA_1 + i,
+ (msg->msg[i]) |
+ (msg->msg[i + 1] << 8) |
+ (msg->msg[i + 2] << 16) |
+ (msg->msg[i + 3] << 24));
+
+ val = HDMI_READ(VC4_HDMI_CEC_CNTRL_1);
+ val &= ~VC4_HDMI_CEC_START_XMIT_BEGIN;
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1, val);
+ val &= ~VC4_HDMI_CEC_MESSAGE_LENGTH_MASK;
+ val |= (msg->len - 1) << VC4_HDMI_CEC_MESSAGE_LENGTH_SHIFT;
+ val |= VC4_HDMI_CEC_START_XMIT_BEGIN;
+
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1, val);
+ return 0;
+}
+
+static const struct cec_adap_ops vc4_hdmi_cec_adap_ops = {
+ .adap_enable = vc4_hdmi_cec_adap_enable,
+ .adap_log_addr = vc4_hdmi_cec_adap_log_addr,
+ .adap_transmit = vc4_hdmi_cec_adap_transmit,
+};
+#endif
+
static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -1247,6 +1414,26 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
ret = PTR_ERR(hdmi->connector);
goto err_destroy_encoder;
}
+#ifdef CONFIG_DRM_VC4_HDMI_CEC
+ hdmi->cec_adap = cec_allocate_adapter(&vc4_hdmi_cec_adap_ops,
+ vc4, "vc4", CEC_CAP_TRANSMIT | CEC_CAP_LOG_ADDRS |
+ CEC_CAP_PASSTHROUGH | CEC_CAP_RC, 1);
+ ret = PTR_ERR_OR_ZERO(hdmi->cec_adap);
+ if (ret < 0)
+ goto err_destroy_conn;
+ HDMI_WRITE(VC4_HDMI_CPU_MASK_SET, 0xffffffff);
+ HDMI_WRITE(VC4_HDMI_CEC_CNTRL_1,
+ (HDMI_READ(VC4_HDMI_CEC_CNTRL_1) | VC4_HDMI_CEC_ADDR_MASK));
+ ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0),
+ vc4_cec_irq_handler,
+ vc4_cec_irq_handler_thread, 0,
+ "vc4 hdmi cec", vc4);
+ if (ret)
+ goto err_delete_cec_adap;
+ ret = cec_register_adapter(hdmi->cec_adap, dev);
+ if (ret < 0)
+ goto err_delete_cec_adap;
+#endif
ret = vc4_hdmi_audio_init(hdmi);
if (ret)
@@ -1254,6 +1441,12 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
return 0;
+#ifdef CONFIG_DRM_VC4_HDMI_CEC
+err_delete_cec_adap:
+ cec_delete_adapter(hdmi->cec_adap);
+err_destroy_conn:
+ vc4_hdmi_connector_destroy(hdmi->connector);
+#endif
err_destroy_encoder:
vc4_hdmi_encoder_destroy(hdmi->encoder);
err_unprepare_hsm:
@@ -1273,7 +1466,7 @@ static void vc4_hdmi_unbind(struct device *dev, struct device *master,
struct vc4_hdmi *hdmi = vc4->hdmi;
vc4_hdmi_audio_cleanup(hdmi);
-
+ cec_unregister_adapter(hdmi->cec_adap);
vc4_hdmi_connector_destroy(hdmi->connector);
vc4_hdmi_encoder_destroy(hdmi->encoder);
diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h
index b18cc20ee185..55677bd50f66 100644
--- a/drivers/gpu/drm/vc4/vc4_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_regs.h
@@ -595,6 +595,7 @@
# define VC4_HDMI_CEC_ADDR_MASK VC4_MASK(15, 12)
# define VC4_HDMI_CEC_ADDR_SHIFT 12
/* Divides off of HSM clock to generate CEC bit clock. */
+/* With the current defaults the CEC bit clock is 40 kHz = 25 usec */
# define VC4_HDMI_CEC_DIV_CLK_CNT_MASK VC4_MASK(11, 0)
# define VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT 0
@@ -670,6 +671,10 @@
# define VC4_HDMI_CPU_CEC BIT(6)
# define VC4_HDMI_CPU_HOTPLUG BIT(0)
+#define VC4_HDMI_CPU_MASK_STATUS 0x34c
+#define VC4_HDMI_CPU_MASK_SET 0x350
+#define VC4_HDMI_CPU_MASK_CLEAR 0x354
+
#define VC4_HDMI_GCP(x) (0x400 + ((x) * 0x4))
#define VC4_HDMI_RAM_PACKET(x) (0x400 + ((x) * 0x24))
#define VC4_HDMI_PACKET_STRIDE 0x24
--
2.11.0
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