[PATCH 2/6] media: qcom: camss: Add CSID 340 support

[Loic Poulain <loic.poulain@oss.qualcomm.com>]

Add support for CSID found in QCM2290, it's a simplified gen-2 version.
- There is no Test Pattern Generator (moved outside CSID)
- There is no subsampling (moved to CAMIF module)

Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
---
 drivers/media/platform/qcom/camss/Makefile    |   1 +
 .../platform/qcom/camss/camss-csid-340.c      | 190 ++++++++++++++++++
 .../media/platform/qcom/camss/camss-csid.h    |   1 +
 3 files changed, 192 insertions(+)
 create mode 100644 drivers/media/platform/qcom/camss/camss-csid-340.c

diff --git a/drivers/media/platform/qcom/camss/Makefile b/drivers/media/platform/qcom/camss/Makefile
index 719898f5d32b..3217bf40976d 100644
--- a/drivers/media/platform/qcom/camss/Makefile
+++ b/drivers/media/platform/qcom/camss/Makefile
@@ -6,6 +6,7 @@ qcom-camss-objs += \
 		camss-csid.o \
 		camss-csid-4-1.o \
 		camss-csid-4-7.o \
+		camss-csid-340.o \
 		camss-csid-680.o \
 		camss-csid-gen2.o \
 		camss-csid-780.o \
diff --git a/drivers/media/platform/qcom/camss/camss-csid-340.c b/drivers/media/platform/qcom/camss/camss-csid-340.c
new file mode 100644
index 000000000000..24f8f6fb6f4c
--- /dev/null
+++ b/drivers/media/platform/qcom/camss/camss-csid-340.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Qualcomm MSM Camera Subsystem - CSID (CSI Decoder) Module 340
+ *
+ * Copyright (c) 2025 Qualcomm Technologies, Inc.
+ */
+
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+
+#include "camss.h"
+#include "camss-csid.h"
+#include "camss-csid-gen2.h"
+
+#define CSID_RST_STROBES					(0x010)
+#define		CSID_RST_SW_REGS			BIT(0)
+#define		CSID_RST_IRQ				BIT(1)
+#define CSID_RST_IFE_CLK				BIT(2)
+#define		CSID_RST_PHY_CLK			BIT(3)
+#define		CSID_RST_CSID_CLK			BIT(4)
+
+#define CSID_IRQ_STATUS						(0x070)
+#define CSID_IRQ_MASK						(0x074)
+#define		CSID_IRQ_MASK_RST_DONE			BIT(0)
+#define CSID_IRQ_CLEAR						(0x078)
+#define CSID_IRQ_CMD						(0x080)
+#define		CSID_IRQ_CMD_CLEAR			BIT(0)
+
+#define CSID_CSI2_RX_CFG0					(0x100)
+#define		CSI2_RX_CFG0_NUM_ACTIVE_LANES		0
+#define		CSI2_RX_CFG0_DL0_INPUT_SEL		4
+#define		CSI2_RX_CFG0_DL1_INPUT_SEL		8
+#define		CSI2_RX_CFG0_DL2_INPUT_SEL		12
+#define		CSI2_RX_CFG0_DL3_INPUT_SEL		16
+#define		CSI2_RX_CFG0_PHY_NUM_SEL		20
+#define		CSI2_RX_CFG0_PHY_SEL_BASE_IDX		1
+#define		CSI2_RX_CFG0_PHY_TYPE_SEL		24
+
+#define CSID_CSI2_RX_CFG1					(0x104)
+#define		CSI2_RX_CFG1_PACKET_ECC_CORRECTION_EN	BIT(0)
+#define		CSI2_RX_CFG1_MISR_EN			BIT(6)
+#define		CSI2_RX_CFG1_CGC_MODE			BIT(7)
+
+#define CSID_RDI_CFG0(rdi)					(0x300 + 0x100 * (rdi))
+#define		CSID_RDI_CFG0_BYTE_CNTR_EN		BIT(0)
+#define		CSID_RDI_CFG0_TIMESTAMP_EN		BIT(1)
+#define		CSID_RDI_CFG0_DECODE_FORMAT_NOP		(0xf << 12)
+#define		CSID_RDI_CFG0_DT(dt)			((dt) << 16)
+#define		CSID_RDI_CFG0_VC(vc)			((vc) << 22)
+#define		CSID_RDI_CFG0_DTID(dtid)		((dtid) << 22)
+#define		CSID_RDI_CFG0_ENABLE			BIT(31)
+
+#define CSID_RDI_CTRL(rdi)					(0x308 + 0x100 * (rdi))
+#define CSID_RDI_CTRL_HALT_AT_FRAME_BOUNDARY		0
+#define CSID_RDI_CTRL_RESUME_AT_FRAME_BOUNDARY		1
+
+static void __csid_configure_rx(struct csid_device *csid,
+				struct csid_phy_config *phy, int vc)
+{
+	u32 val;
+
+	val = (phy->lane_cnt - 1) << CSI2_RX_CFG0_NUM_ACTIVE_LANES;
+	val |= phy->lane_assign << CSI2_RX_CFG0_DL0_INPUT_SEL;
+	val |= (phy->csiphy_id + CSI2_RX_CFG0_PHY_SEL_BASE_IDX) << CSI2_RX_CFG0_PHY_NUM_SEL;
+	writel_relaxed(val, csid->base + CSID_CSI2_RX_CFG0);
+
+	val = CSI2_RX_CFG1_PACKET_ECC_CORRECTION_EN;
+	writel_relaxed(val, csid->base + CSID_CSI2_RX_CFG1);
+}
+
+static void __csid_ctrl_rdi(struct csid_device *csid, int enable, u8 rdi)
+{
+	writel(!!enable, csid->base + CSID_RDI_CTRL(rdi));
+}
+
+static void __csid_configure_rdi_stream(struct csid_device *csid, u8 enable, u8 vc)
+{
+	struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_FIRST_SRC + vc];
+	const struct csid_format_info *format = csid_get_fmt_entry(csid->res->formats->formats,
+								   csid->res->formats->nformats,
+								   input_format->code);
+	u8 lane_cnt = csid->phy.lane_cnt;
+	u8 dt_id;
+	u32 val;
+
+	if (!lane_cnt)
+		lane_cnt = 4;
+
+	/*
+	 * DT_ID is a two bit bitfield that is concatenated with
+	 * the four least significant bits of the five bit VC
+	 * bitfield to generate an internal CID value.
+	 *
+	 * CSID_RDI_CFG0(vc)
+	 * DT_ID : 28:27
+	 * VC    : 26:22
+	 * DT    : 21:16
+	 *
+	 * CID   : VC 3:0 << 2 | DT_ID 1:0
+	 */
+	dt_id = vc & 0x03;
+
+	val = CSID_RDI_CFG0_DECODE_FORMAT_NOP; /* only for RDI path */
+	val |= CSID_RDI_CFG0_DT(format->data_type);
+	val |= CSID_RDI_CFG0_VC(vc);
+	val |= CSID_RDI_CFG0_DTID(dt_id);
+
+	if (enable)
+		val |= CSID_RDI_CFG0_ENABLE;
+
+	dev_dbg(csid->camss->dev, "CSID%u: Stream %s (dt:0x%x vc=%u)\n",
+		csid->id, enable ? "enable" : "disable", format->data_type, vc);
+
+	writel_relaxed(val, csid->base + CSID_RDI_CFG0(vc));
+}
+
+static void csid_configure_stream(struct csid_device *csid, u8 enable)
+{
+	int i;
+
+	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_ctrl_rdi(csid, enable, i);
+		}
+	}
+}
+
+static int csid_reset(struct csid_device *csid)
+{
+	unsigned long time;
+
+	writel_relaxed(CSID_IRQ_MASK_RST_DONE, csid->base + CSID_IRQ_MASK);
+	writel_relaxed(CSID_IRQ_MASK_RST_DONE, csid->base + CSID_IRQ_CLEAR);
+	writel_relaxed(CSID_IRQ_CMD_CLEAR, csid->base + CSID_IRQ_CMD);
+
+	reinit_completion(&csid->reset_complete);
+
+	/* Reset with registers preserved */
+	writel(CSID_RST_IRQ | CSID_RST_IFE_CLK | CSID_RST_PHY_CLK | CSID_RST_CSID_CLK,
+	       csid->base + CSID_RST_STROBES);
+
+	time = wait_for_completion_timeout(&csid->reset_complete,
+					   msecs_to_jiffies(CSID_RESET_TIMEOUT_MS));
+	if (!time) {
+		dev_err(csid->camss->dev, "CSID%u: reset timeout\n", csid->id);
+		return -EIO;
+	}
+
+	dev_dbg(csid->camss->dev, "CSID%u: reset done\n", csid->id);
+
+	return 0;
+}
+
+static irqreturn_t csid_isr(int irq, void *dev)
+{
+	struct csid_device *csid = dev;
+	u32 val;
+
+	val = readl_relaxed(csid->base + CSID_IRQ_STATUS);
+	writel_relaxed(val, csid->base + CSID_IRQ_CLEAR);
+	writel_relaxed(CSID_IRQ_CMD_CLEAR, csid->base + CSID_IRQ_CMD);
+
+	if (val & CSID_IRQ_MASK_RST_DONE)
+		complete(&csid->reset_complete);
+	else
+		dev_warn_ratelimited(csid->camss->dev, "Spurious CSID interrupt\n");
+
+	return IRQ_HANDLED;
+}
+
+static int csid_configure_testgen_pattern(struct csid_device *csid, s32 val)
+{
+	return -EOPNOTSUPP; /* Not part of CSID */
+}
+
+static void csid_subdev_init(struct csid_device *csid) {}
+
+const struct csid_hw_ops csid_ops_340 = {
+	.configure_testgen_pattern = csid_configure_testgen_pattern,
+	.configure_stream = csid_configure_stream,
+	.hw_version = csid_hw_version,
+	.isr = csid_isr,
+	.reset = csid_reset,
+	.src_pad_code = csid_src_pad_code,
+	.subdev_init = csid_subdev_init,
+};
diff --git a/drivers/media/platform/qcom/camss/camss-csid.h b/drivers/media/platform/qcom/camss/camss-csid.h
index 9dc826d8c8f6..3399e92658d8 100644
--- a/drivers/media/platform/qcom/camss/camss-csid.h
+++ b/drivers/media/platform/qcom/camss/camss-csid.h
@@ -213,6 +213,7 @@ extern const struct csid_formats csid_formats_gen2;
 
 extern const struct csid_hw_ops csid_ops_4_1;
 extern const struct csid_hw_ops csid_ops_4_7;
+extern const struct csid_hw_ops csid_ops_340;
 extern const struct csid_hw_ops csid_ops_680;
 extern const struct csid_hw_ops csid_ops_gen2;
 extern const struct csid_hw_ops csid_ops_780;
-- 
2.34.1