From: Hans Verkuil <hans.verk...@cisco.com>
Add HDMI CEC support to the Allwinner A10 SoC.
This SoC uses a poor-man's CEC implementation by polling the CEC pin. It is
using the CEC_PIN core implementation for such devices to do the heavy
lifting. It just provides the callbacks to read/drive the CEC pin.
Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
---
drivers/gpu/drm/sun4i/Kconfig | 9 ++++++
drivers/gpu/drm/sun4i/sun4i_hdmi.h | 8 +++++
drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c | 57 +++++++++++++++++++++++++++++++++-
3 files changed, 73 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/sun4i/Kconfig b/drivers/gpu/drm/sun4i/Kconfig
index 5bcad8f5fb4f..e884d265c0b3 100644
--- a/drivers/gpu/drm/sun4i/Kconfig
+++ b/drivers/gpu/drm/sun4i/Kconfig
@@ -21,6 +21,15 @@ config DRM_SUN4I_HDMI
Choose this option if you have an Allwinner SoC with an HDMI
controller.
+config DRM_SUN4I_HDMI_CEC
+ bool "Allwinner A10 HDMI CEC Support"
+ depends on DRM_SUN4I_HDMI
+ select CEC_CORE
+ select CEC_PIN
+ help
+ Choose this option if you have an Allwinner SoC with an HDMI
+ controller and want to use CEC.
+
config DRM_SUN4I_BACKEND
tristate "Support for Allwinner A10 Display Engine Backend"
depends on DRM_SUN4I
diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi.h
b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
index 2f2f2ff1ea63..8263de225b36 100644
--- a/drivers/gpu/drm/sun4i/sun4i_hdmi.h
+++ b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
@@ -15,6 +15,8 @@
#include <drm/drm_connector.h>
#include <drm/drm_encoder.h>
+#include <media/cec-pin.h>
+
#define SUN4I_HDMI_CTRL_REG 0x004
#define SUN4I_HDMI_CTRL_ENABLE BIT(31)
@@ -86,6 +88,11 @@
#define SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK BIT(21)
#define SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_SHIFT 21
+#define SUN4I_HDMI_CEC 0x214
+#define SUN4I_HDMI_CEC_ENABLE BIT(11)
+#define SUN4I_HDMI_CEC_TX BIT(9)
+#define SUN4I_HDMI_CEC_RX BIT(8)
+
#define SUN4I_HDMI_PKT_CTRL_REG(n) (0x2f0 + (4 * (n)))
#define SUN4I_HDMI_PKT_CTRL_TYPE(n, t) ((t) << (((n) % 4) * 4))
@@ -149,6 +156,7 @@ struct sun4i_hdmi {
struct sun4i_drv *drv;
bool hdmi_monitor;
+ struct cec_adapter *cec_adap;
};
int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *clk);
diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c
b/drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c
index d3398f6250ef..8b89b4e25893 100644
--- a/drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c
+++ b/drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c
@@ -271,6 +271,9 @@ static int sun4i_hdmi_get_modes(struct drm_connector
*connector)
clk_set_rate(hdmi->ddc_clk, 100000);
edid = drm_do_get_edid(connector, sun4i_hdmi_read_edid_block, hdmi);
+
+ cec_s_phys_addr_from_edid(hdmi->cec_adap, edid);
+
if (!edid)
return 0;
@@ -299,8 +302,10 @@ sun4i_hdmi_connector_detect(struct drm_connector
*connector, bool force)
if (readl_poll_timeout(hdmi->base + SUN4I_HDMI_HPD_REG, reg,
reg & SUN4I_HDMI_HPD_HIGH,
- 0, 500000))
+ 0, 500000)) {
+ cec_phys_addr_invalidate(hdmi->cec_adap);
return connector_status_disconnected;
+ }
return connector_status_connected;
}
@@ -315,6 +320,40 @@ static const struct drm_connector_funcs
sun4i_hdmi_connector_funcs = {
.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};
+#ifdef CONFIG_DRM_SUN4I_HDMI_CEC
+static bool sun4i_hdmi_cec_pin_read(struct cec_adapter *adap)
+{
+ struct sun4i_hdmi *hdmi = cec_get_drvdata(adap);
+
+ return readl(hdmi->base + SUN4I_HDMI_CEC) & SUN4I_HDMI_CEC_RX;
+}
+
+static void sun4i_hdmi_cec_pin_low(struct cec_adapter *adap)
+{
+ struct sun4i_hdmi *hdmi = cec_get_drvdata(adap);
+
+ /* Start driving the CEC pin low */
+ writel(SUN4I_HDMI_CEC_ENABLE, hdmi->base + SUN4I_HDMI_CEC);
+}
+
+static void sun4i_hdmi_cec_pin_high(struct cec_adapter *adap)
+{
+ struct sun4i_hdmi *hdmi = cec_get_drvdata(adap);
+
+ /*
+ * Stop driving the CEC pin, the pull up will take over
+ * unless another CEC device is driving the pin low.
+ */
+ writel(0, hdmi->base + SUN4I_HDMI_CEC);
+}
+
+static const struct cec_pin_ops sun4i_hdmi_cec_pin_ops = {
+ .read = sun4i_hdmi_cec_pin_read,
+ .low = sun4i_hdmi_cec_pin_low,
+ .high = sun4i_hdmi_cec_pin_high,
+};
+#endif
+
static int sun4i_hdmi_bind(struct device *dev, struct device *master,
void *data)
{
@@ -430,6 +469,17 @@ static int sun4i_hdmi_bind(struct device *dev, struct
device *master,
if (!hdmi->encoder.possible_crtcs)
return -EPROBE_DEFER;
+#ifdef CONFIG_DRM_SUN4I_HDMI_CEC
+ hdmi->cec_adap = cec_pin_allocate_adapter(&sun4i_hdmi_cec_pin_ops,
+ hdmi, "sun4i", CEC_CAP_TRANSMIT | CEC_CAP_LOG_ADDRS |
+ CEC_CAP_PASSTHROUGH | CEC_CAP_RC);
+ ret = PTR_ERR_OR_ZERO(hdmi->cec_adap);
+ if (ret < 0)
+ goto err_cleanup_connector;
+ writel(readl(hdmi->base + SUN4I_HDMI_CEC) & ~SUN4I_HDMI_CEC_TX,
+ hdmi->base + SUN4I_HDMI_CEC);
+#endif
+
drm_connector_helper_add(&hdmi->connector,
&sun4i_hdmi_connector_helper_funcs);
ret = drm_connector_init(drm, &hdmi->connector,
@@ -445,11 +495,15 @@ static int sun4i_hdmi_bind(struct device *dev, struct
device *master,
hdmi->connector.polled = DRM_CONNECTOR_POLL_CONNECT |
DRM_CONNECTOR_POLL_DISCONNECT;
+ ret = cec_register_adapter(hdmi->cec_adap, dev);
+ if (ret < 0)
+ goto err_cleanup_connector;
drm_mode_connector_attach_encoder(&hdmi->connector, &hdmi->encoder);
return 0;
err_cleanup_connector:
+ cec_delete_adapter(hdmi->cec_adap);
drm_encoder_cleanup(&hdmi->encoder);
return ret;
}
@@ -459,6 +513,7 @@ static void sun4i_hdmi_unbind(struct device *dev, struct
device *master,
{
struct sun4i_hdmi *hdmi = dev_get_drvdata(dev);
+ cec_unregister_adapter(hdmi->cec_adap);
drm_connector_cleanup(&hdmi->connector);
drm_encoder_cleanup(&hdmi->encoder);
}
--
2.11.0
