[PATCH v2 1/5] media: qcom: camss: Fix RDI streaming for CSID 680

[bod@kernel.org]

From: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

Fix streaming to RDI1 and RDI2. csid->phy.en_vc contains a bitmask of
enabled CSID ports not virtual channels.

We cycle through the number of available CSID ports and test this value
against the vc_en bitmask.

We then use the passed value both as an index to the port configuration
macros and as a virtual channel index.

This is a very broken pattern. Reviewing the initial introduction of VC
support it states that you can only map one CSID to one VFE. This is true
however each CSID has multiple sources which can sink inside of the VFE -
for example there is a "pixel" path for bayer stats which sources @
CSID(x):3 and sinks on VFE(x):pix.

That is CSID port # 3 should drive VFE port #3. With our current setup only
a sensor which drives virtual channel number #3 could possibly enable that
setup.

This is deeply wrong the virtual channel has no relevance to hooking CSID
to VFE, a fact that is proven after this patch is applied allowing
RDI0,RDI1 and RDI2 to function with VC0 whereas before only RDI1 worked.

Another way the current model breaks is the DT field. A sensor driving
different data-types on the same VC would not be able to separate the VC:DT
pair to separate RDI outputs, thus breaking another feature of VCs in the
MIPI data-stream.

Default the VC back to zero. A follow on series will implement subdev
streams to actually enable VCs without breaking CSID source to VFE sink.

Fixes: 253314b20408 ("media: qcom: camss: Add CSID 680 support")
Cc: stable@vger.kernel.org
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 drivers/media/platform/qcom/camss/camss-csid-680.c | 28 +++++++++++-----------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-csid-680.c b/drivers/media/platform/qcom/camss/camss-csid-680.c
index 3ad3a174bcfb8..0fc908096a99b 100644
--- a/drivers/media/platform/qcom/camss/camss-csid-680.c
+++ b/drivers/media/platform/qcom/camss/camss-csid-680.c
@@ -219,9 +219,9 @@ static void __csid_configure_top(struct csid_device *csid)
 	    CSID_TOP_IO_PATH_CFG0(csid->id));
 }
 
-static void __csid_configure_rdi_stream(struct csid_device *csid, u8 enable, u8 vc)
+static void __csid_configure_rdi_stream(struct csid_device *csid, u8 enable, u8 port, u8 vc)
 {
-	struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_FIRST_SRC + vc];
+	struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_FIRST_SRC + port];
 	const struct csid_format_info *format = csid_get_fmt_entry(csid->res->formats->formats,
 								   csid->res->formats->nformats,
 								   input_format->code);
@@ -240,21 +240,21 @@ static void __csid_configure_rdi_stream(struct csid_device *csid, u8 enable, u8
 	 * the four least significant bits of the five bit VC
 	 * bitfield to generate an internal CID value.
 	 *
-	 * CSID_RDI_CFG0(vc)
+	 * CSID_RDI_CFG0(port)
 	 * DT_ID : 28:27
 	 * VC    : 26:22
 	 * DT    : 21:16
 	 *
 	 * CID   : VC 3:0 << 2 | DT_ID 1:0
 	 */
-	dt_id = vc & 0x03;
+	dt_id = port & 0x03;
 
 	/* note: for non-RDI path, this should be format->decode_format */
 	val |= DECODE_FORMAT_PAYLOAD_ONLY << RDI_CFG0_DECODE_FORMAT;
 	val |= format->data_type << RDI_CFG0_DATA_TYPE;
 	val |= vc << RDI_CFG0_VIRTUAL_CHANNEL;
 	val |= dt_id << RDI_CFG0_DT_ID;
-	writel(val, csid->base + CSID_RDI_CFG0(vc));
+	writel(val, csid->base + CSID_RDI_CFG0(port));
 
 	val = RDI_CFG1_TIMESTAMP_STB_FRAME;
 	val |= RDI_CFG1_BYTE_CNTR_EN;
@@ -265,23 +265,23 @@ static void __csid_configure_rdi_stream(struct csid_device *csid, u8 enable, u8
 	val |= RDI_CFG1_CROP_V_EN;
 	val |= RDI_CFG1_PACKING_MIPI;
 
-	writel(val, csid->base + CSID_RDI_CFG1(vc));
+	writel(val, csid->base + CSID_RDI_CFG1(port));
 
 	val = 0;
-	writel(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(vc));
+	writel(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(port));
 
 	val = 1;
-	writel(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(vc));
+	writel(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(port));
 
 	val = 0;
-	writel(val, csid->base + CSID_RDI_CTRL(vc));
+	writel(val, csid->base + CSID_RDI_CTRL(port));
 
-	val = readl(csid->base + CSID_RDI_CFG0(vc));
+	val = readl(csid->base + CSID_RDI_CFG0(port));
 	if (enable)
 		val |= RDI_CFG0_ENABLE;
 	else
 		val &= ~RDI_CFG0_ENABLE;
-	writel(val, csid->base + CSID_RDI_CFG0(vc));
+	writel(val, csid->base + CSID_RDI_CFG0(port));
 }
 
 static void csid_configure_stream(struct csid_device *csid, u8 enable)
@@ -290,11 +290,11 @@ static void csid_configure_stream(struct csid_device *csid, u8 enable)
 
 	__csid_configure_top(csid);
 
-       /* Loop through all enabled VCs and configure stream for each */
+	/* Loop through all enabled ports and configure a stream for each */
 	for (i = 0; i < MSM_CSID_MAX_SRC_STREAMS; i++) {
 		if (csid->phy.en_vc & BIT(i)) {
-			__csid_configure_rdi_stream(csid, enable, i);
-			__csid_configure_rx(csid, &csid->phy, i);
+			__csid_configure_rdi_stream(csid, enable, i, 0);
+			__csid_configure_rx(csid, &csid->phy, 0);
 			__csid_ctrl_rdi(csid, enable, i);
 		}
 	}

-- 
2.52.0