[PATCH v4 52/78] drm/vc4: hdmi: Add reset callback

From: Maxime Ripard
Date: Wed Jul 08 2020 - 13:43:54 EST


The BCM2711 and BCM283x HDMI controllers use a slightly different reset
sequence, so let's add a callback to reset the controller.

Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 31 ++++++++++++++++++-------------
drivers/gpu/drm/vc4/vc4_hdmi.h | 3 +++
2 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index a4fed1439bf3..80bc3dd9d4a8 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -69,6 +69,21 @@ static int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused)
return 0;
}

+static void vc4_hdmi_reset(struct vc4_hdmi *vc4_hdmi)
+{
+ HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_SW_RST);
+ udelay(1);
+ HDMI_WRITE(HDMI_M_CTL, 0);
+
+ HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_ENABLE);
+
+ HDMI_WRITE(HDMI_SW_RESET_CONTROL,
+ VC4_HDMI_SW_RESET_HDMI |
+ VC4_HDMI_SW_RESET_FORMAT_DETECT);
+
+ HDMI_WRITE(HDMI_SW_RESET_CONTROL, 0);
+}
+
static enum drm_connector_status
vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
{
@@ -363,11 +378,8 @@ static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder)
return;
}

- HDMI_WRITE(HDMI_SW_RESET_CONTROL,
- VC4_HDMI_SW_RESET_HDMI |
- VC4_HDMI_SW_RESET_FORMAT_DETECT);
-
- HDMI_WRITE(HDMI_SW_RESET_CONTROL, 0);
+ if (vc4_hdmi->variant->reset)
+ vc4_hdmi->variant->reset(vc4_hdmi);

/* PHY should be in reset, like
* vc4_hdmi_encoder_disable() does.
@@ -1292,14 +1304,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
vc4_hdmi->hpd_active_low = hpd_gpio_flags & OF_GPIO_ACTIVE_LOW;
}

- /* HDMI core must be enabled. */
- if (!(HDMI_READ(HDMI_M_CTL) & VC4_HD_M_ENABLE)) {
- HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_SW_RST);
- udelay(1);
- HDMI_WRITE(HDMI_M_CTL, 0);
-
- HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_ENABLE);
- }
pm_runtime_enable(dev);

drm_simple_encoder_init(drm, encoder, DRM_MODE_ENCODER_TMDS);
@@ -1428,6 +1432,7 @@ static const struct vc4_hdmi_variant bcm2835_variant = {
.num_registers = ARRAY_SIZE(vc4_hdmi_fields),

.init_resources = vc4_hdmi_init_resources,
+ .reset = vc4_hdmi_reset,
};

static const struct of_device_id vc4_hdmi_dt_match[] = {
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index b36e0210671f..17a30589f39c 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -35,6 +35,9 @@ struct vc4_hdmi_variant {
* clocks, etc) for that variant.
*/
int (*init_resources)(struct vc4_hdmi *vc4_hdmi);
+
+ /* Callback to reset the HDMI block */
+ void (*reset)(struct vc4_hdmi *vc4_hdmi);
};

/* HDMI audio information */
--
git-series 0.9.1