[PATCH 03/15] drm/vc4: hdmi: Fix register offset with longer CEC messages
From: Maxime Ripard <hidden>
Date: 2020-12-10 14:07:18
Also in:
dri-devel, linux-media, lkml
Subsystem:
drm drivers, drm drivers and misc gpu patches, drm drivers for vc4, the rest · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Dave Stevenson, Linus Torvalds
From: Dom Cobley <redacted>
The code prior to 311e305fdb4e ("drm/vc4: hdmi: Implement a register
layout abstraction") was relying on the fact that the register offset
was incremented by 4 for each readl call. That worked since the register
width is 4 bytes.
However, since that commit the HDMI_READ macro is now taking an enum,
and the offset doesn't increment by 4 but 1 now. Divide the index by 4
to fix this.
Fixes: 311e305fdb4e ("drm/vc4: hdmi: Implement a register layout abstraction")
Signed-off-by: Dom Cobley <redacted>
Signed-off-by: Maxime Ripard <redacted>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 3df1747dd917..28b78ea885ea 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c@@ -1434,13 +1434,20 @@ static irqreturn_t vc4_cec_irq_handler_thread(int irq, void *priv) static void vc4_cec_read_msg(struct vc4_hdmi *vc4_hdmi, u32 cntrl1) { + struct drm_device *dev = vc4_hdmi->connector.dev; 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); + + if (msg->len > 16) { + drm_err(dev, "Attempting to read too much data (%d)\n", msg->len); + return; + } + for (i = 0; i < msg->len; i += 4) { - u32 val = HDMI_READ(HDMI_CEC_RX_DATA_1 + i); + u32 val = HDMI_READ(HDMI_CEC_RX_DATA_1 + (i >> 2)); msg->msg[i] = val & 0xff; msg->msg[i + 1] = (val >> 8) & 0xff;
@@ -1533,11 +1540,17 @@ static int vc4_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, u32 signal_free_time, struct cec_msg *msg) { struct vc4_hdmi *vc4_hdmi = cec_get_drvdata(adap); + struct drm_device *dev = vc4_hdmi->connector.dev; u32 val; unsigned int i; + if (msg->len > 16) { + drm_err(dev, "Attempting to transmit too much data (%d)\n", msg->len); + return -ENOMEM; + } + for (i = 0; i < msg->len; i += 4) - HDMI_WRITE(HDMI_CEC_TX_DATA_1 + i, + HDMI_WRITE(HDMI_CEC_TX_DATA_1 + (i >> 2), (msg->msg[i]) | (msg->msg[i + 1] << 8) | (msg->msg[i + 2] << 16) |
--
2.28.0
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