Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 908 insertions, 0 deletions

diff --git a/drivers/media/platform/qcom/camss/camss-csid.c b/drivers/media/platform/qcom/camss/camss-csid.c
new file mode 100644
index 000000000..6360314f0
--- /dev/null
+++ b/drivers/media/platform/qcom/camss/camss-csid.c
@@ -0,0 +1,908 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * camss-csid.c
+ *
+ * Qualcomm MSM Camera Subsystem - CSID (CSI Decoder) Module
+ *
+ * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2015-2018 Linaro Ltd.
+ */
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <media/media-entity.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-subdev.h>
+
+#include "camss-csid.h"
+#include "camss-csid-gen1.h"
+#include "camss.h"
+
+/* offset of CSID registers in VFE region for VFE 480 */
+#define VFE_480_CSID_OFFSET 0x1200
+#define VFE_480_LITE_CSID_OFFSET 0x200
+
+#define MSM_CSID_NAME "msm_csid"
+
+const char * const csid_testgen_modes[] = {
+	"Disabled",
+	"Incrementing",
+	"Alternating 0x55/0xAA",
+	"All Zeros 0x00",
+	"All Ones 0xFF",
+	"Pseudo-random Data",
+	"User Specified",
+	"Complex pattern",
+	"Color box",
+	"Color bars",
+	NULL
+};
+
+u32 csid_find_code(u32 *codes, unsigned int ncodes,
+		   unsigned int match_format_idx, u32 match_code)
+{
+	int i;
+
+	if (!match_code && (match_format_idx >= ncodes))
+		return 0;
+
+	for (i = 0; i < ncodes; i++)
+		if (match_code) {
+			if (codes[i] == match_code)
+				return match_code;
+		} else {
+			if (i == match_format_idx)
+				return codes[i];
+		}
+
+	return codes[0];
+}
+
+const struct csid_format *csid_get_fmt_entry(const struct csid_format *formats,
+					     unsigned int nformats,
+					     u32 code)
+{
+	unsigned int i;
+
+	for (i = 0; i < nformats; i++)
+		if (code == formats[i].code)
+			return &formats[i];
+
+	WARN(1, "Unknown format\n");
+
+	return &formats[0];
+}
+
+/*
+ * csid_set_clock_rates - Calculate and set clock rates on CSID module
+ * @csiphy: CSID device
+ */
+static int csid_set_clock_rates(struct csid_device *csid)
+{
+	struct device *dev = csid->camss->dev;
+	const struct csid_format *fmt;
+	s64 link_freq;
+	int i, j;
+	int ret;
+
+	fmt = csid_get_fmt_entry(csid->formats, csid->nformats,
+				 csid->fmt[MSM_CSIPHY_PAD_SINK].code);
+	link_freq = camss_get_link_freq(&csid->subdev.entity, fmt->bpp,
+					csid->phy.lane_cnt);
+	if (link_freq < 0)
+		link_freq = 0;
+
+	for (i = 0; i < csid->nclocks; i++) {
+		struct camss_clock *clock = &csid->clock[i];
+
+		if (!strcmp(clock->name, "csi0") ||
+		    !strcmp(clock->name, "csi1") ||
+		    !strcmp(clock->name, "csi2") ||
+		    !strcmp(clock->name, "csi3")) {
+			u64 min_rate = link_freq / 4;
+			long rate;
+
+			camss_add_clock_margin(&min_rate);
+
+			for (j = 0; j < clock->nfreqs; j++)
+				if (min_rate < clock->freq[j])
+					break;
+
+			if (j == clock->nfreqs) {
+				dev_err(dev,
+					"Pixel clock is too high for CSID\n");
+				return -EINVAL;
+			}
+
+			/* if sensor pixel clock is not available */
+			/* set highest possible CSID clock rate */
+			if (min_rate == 0)
+				j = clock->nfreqs - 1;
+
+			rate = clk_round_rate(clock->clk, clock->freq[j]);
+			if (rate < 0) {
+				dev_err(dev, "clk round rate failed: %ld\n",
+					rate);
+				return -EINVAL;
+			}
+
+			ret = clk_set_rate(clock->clk, rate);
+			if (ret < 0) {
+				dev_err(dev, "clk set rate failed: %d\n", ret);
+				return ret;
+			}
+		} else if (clock->nfreqs) {
+			clk_set_rate(clock->clk, clock->freq[0]);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * csid_set_power - Power on/off CSID module
+ * @sd: CSID V4L2 subdevice
+ * @on: Requested power state
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+static int csid_set_power(struct v4l2_subdev *sd, int on)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+	struct camss *camss = csid->camss;
+	struct device *dev = camss->dev;
+	struct vfe_device *vfe = &camss->vfe[csid->id];
+	u32 version = camss->version;
+	int ret = 0;
+
+	if (on) {
+		if (version == CAMSS_8250 || version == CAMSS_845) {
+			ret = vfe_get(vfe);
+			if (ret < 0)
+				return ret;
+		}
+
+		ret = pm_runtime_resume_and_get(dev);
+		if (ret < 0)
+			return ret;
+
+		ret = regulator_bulk_enable(csid->num_supplies,
+					    csid->supplies);
+		if (ret < 0) {
+			pm_runtime_put_sync(dev);
+			return ret;
+		}
+
+		ret = csid_set_clock_rates(csid);
+		if (ret < 0) {
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
+			pm_runtime_put_sync(dev);
+			return ret;
+		}
+
+		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
+		if (ret < 0) {
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
+			pm_runtime_put_sync(dev);
+			return ret;
+		}
+
+		csid->phy.need_vc_update = true;
+
+		enable_irq(csid->irq);
+
+		ret = csid->ops->reset(csid);
+		if (ret < 0) {
+			disable_irq(csid->irq);
+			camss_disable_clocks(csid->nclocks, csid->clock);
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
+			pm_runtime_put_sync(dev);
+			return ret;
+		}
+
+		csid->ops->hw_version(csid);
+	} else {
+		disable_irq(csid->irq);
+		camss_disable_clocks(csid->nclocks, csid->clock);
+		regulator_bulk_disable(csid->num_supplies,
+				       csid->supplies);
+		pm_runtime_put_sync(dev);
+		if (version == CAMSS_8250 || version == CAMSS_845)
+			vfe_put(vfe);
+	}
+
+	return ret;
+}
+
+/*
+ * csid_set_stream - Enable/disable streaming on CSID module
+ * @sd: CSID V4L2 subdevice
+ * @enable: Requested streaming state
+ *
+ * Main configuration of CSID module is also done here.
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+static int csid_set_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+	int ret;
+
+	if (enable) {
+		ret = v4l2_ctrl_handler_setup(&csid->ctrls);
+		if (ret < 0) {
+			dev_err(csid->camss->dev,
+				"could not sync v4l2 controls: %d\n", ret);
+			return ret;
+		}
+
+		if (!csid->testgen.enabled &&
+		    !media_pad_remote_pad_first(&csid->pads[MSM_CSID_PAD_SINK]))
+			return -ENOLINK;
+	}
+
+	if (csid->phy.need_vc_update) {
+		csid->ops->configure_stream(csid, enable);
+		csid->phy.need_vc_update = false;
+	}
+
+	return 0;
+}
+
+/*
+ * __csid_get_format - Get pointer to format structure
+ * @csid: CSID device
+ * @cfg: V4L2 subdev pad configuration
+ * @pad: pad from which format is requested
+ * @which: TRY or ACTIVE format
+ *
+ * Return pointer to TRY or ACTIVE format structure
+ */
+static struct v4l2_mbus_framefmt *
+__csid_get_format(struct csid_device *csid,
+		  struct v4l2_subdev_state *sd_state,
+		  unsigned int pad,
+		  enum v4l2_subdev_format_whence which)
+{
+	if (which == V4L2_SUBDEV_FORMAT_TRY)
+		return v4l2_subdev_get_try_format(&csid->subdev, sd_state,
+						  pad);
+
+	return &csid->fmt[pad];
+}
+
+/*
+ * csid_try_format - Handle try format by pad subdev method
+ * @csid: CSID device
+ * @cfg: V4L2 subdev pad configuration
+ * @pad: pad on which format is requested
+ * @fmt: pointer to v4l2 format structure
+ * @which: wanted subdev format
+ */
+static void csid_try_format(struct csid_device *csid,
+			    struct v4l2_subdev_state *sd_state,
+			    unsigned int pad,
+			    struct v4l2_mbus_framefmt *fmt,
+			    enum v4l2_subdev_format_whence which)
+{
+	unsigned int i;
+
+	switch (pad) {
+	case MSM_CSID_PAD_SINK:
+		/* Set format on sink pad */
+
+		for (i = 0; i < csid->nformats; i++)
+			if (fmt->code == csid->formats[i].code)
+				break;
+
+		/* If not found, use UYVY as default */
+		if (i >= csid->nformats)
+			fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
+
+		fmt->width = clamp_t(u32, fmt->width, 1, 8191);
+		fmt->height = clamp_t(u32, fmt->height, 1, 8191);
+
+		fmt->field = V4L2_FIELD_NONE;
+		fmt->colorspace = V4L2_COLORSPACE_SRGB;
+
+		break;
+
+	case MSM_CSID_PAD_SRC:
+		if (csid->testgen_mode->cur.val == 0) {
+			/* Test generator is disabled, */
+			/* keep pad formats in sync */
+			u32 code = fmt->code;
+
+			*fmt = *__csid_get_format(csid, sd_state,
+						      MSM_CSID_PAD_SINK, which);
+			fmt->code = csid->ops->src_pad_code(csid, fmt->code, 0, code);
+		} else {
+			/* Test generator is enabled, set format on source */
+			/* pad to allow test generator usage */
+
+			for (i = 0; i < csid->nformats; i++)
+				if (csid->formats[i].code == fmt->code)
+					break;
+
+			/* If not found, use UYVY as default */
+			if (i >= csid->nformats)
+				fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
+
+			fmt->width = clamp_t(u32, fmt->width, 1, 8191);
+			fmt->height = clamp_t(u32, fmt->height, 1, 8191);
+
+			fmt->field = V4L2_FIELD_NONE;
+		}
+		break;
+	}
+
+	fmt->colorspace = V4L2_COLORSPACE_SRGB;
+}
+
+/*
+ * csid_enum_mbus_code - Handle pixel format enumeration
+ * @sd: CSID V4L2 subdevice
+ * @cfg: V4L2 subdev pad configuration
+ * @code: pointer to v4l2_subdev_mbus_code_enum structure
+ * return -EINVAL or zero on success
+ */
+static int csid_enum_mbus_code(struct v4l2_subdev *sd,
+			       struct v4l2_subdev_state *sd_state,
+			       struct v4l2_subdev_mbus_code_enum *code)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+
+	if (code->pad == MSM_CSID_PAD_SINK) {
+		if (code->index >= csid->nformats)
+			return -EINVAL;
+
+		code->code = csid->formats[code->index].code;
+	} else {
+		if (csid->testgen_mode->cur.val == 0) {
+			struct v4l2_mbus_framefmt *sink_fmt;
+
+			sink_fmt = __csid_get_format(csid, sd_state,
+						     MSM_CSID_PAD_SINK,
+						     code->which);
+
+			code->code = csid->ops->src_pad_code(csid, sink_fmt->code,
+						       code->index, 0);
+			if (!code->code)
+				return -EINVAL;
+		} else {
+			if (code->index >= csid->nformats)
+				return -EINVAL;
+
+			code->code = csid->formats[code->index].code;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * csid_enum_frame_size - Handle frame size enumeration
+ * @sd: CSID V4L2 subdevice
+ * @cfg: V4L2 subdev pad configuration
+ * @fse: pointer to v4l2_subdev_frame_size_enum structure
+ * return -EINVAL or zero on success
+ */
+static int csid_enum_frame_size(struct v4l2_subdev *sd,
+				struct v4l2_subdev_state *sd_state,
+				struct v4l2_subdev_frame_size_enum *fse)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt format;
+
+	if (fse->index != 0)
+		return -EINVAL;
+
+	format.code = fse->code;
+	format.width = 1;
+	format.height = 1;
+	csid_try_format(csid, sd_state, fse->pad, &format, fse->which);
+	fse->min_width = format.width;
+	fse->min_height = format.height;
+
+	if (format.code != fse->code)
+		return -EINVAL;
+
+	format.code = fse->code;
+	format.width = -1;
+	format.height = -1;
+	csid_try_format(csid, sd_state, fse->pad, &format, fse->which);
+	fse->max_width = format.width;
+	fse->max_height = format.height;
+
+	return 0;
+}
+
+/*
+ * csid_get_format - Handle get format by pads subdev method
+ * @sd: CSID V4L2 subdevice
+ * @cfg: V4L2 subdev pad configuration
+ * @fmt: pointer to v4l2 subdev format structure
+ *
+ * Return -EINVAL or zero on success
+ */
+static int csid_get_format(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_state *sd_state,
+			   struct v4l2_subdev_format *fmt)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt *format;
+
+	format = __csid_get_format(csid, sd_state, fmt->pad, fmt->which);
+	if (format == NULL)
+		return -EINVAL;
+
+	fmt->format = *format;
+
+	return 0;
+}
+
+/*
+ * csid_set_format - Handle set format by pads subdev method
+ * @sd: CSID V4L2 subdevice
+ * @cfg: V4L2 subdev pad configuration
+ * @fmt: pointer to v4l2 subdev format structure
+ *
+ * Return -EINVAL or zero on success
+ */
+static int csid_set_format(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_state *sd_state,
+			   struct v4l2_subdev_format *fmt)
+{
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt *format;
+	int i;
+
+	format = __csid_get_format(csid, sd_state, fmt->pad, fmt->which);
+	if (format == NULL)
+		return -EINVAL;
+
+	csid_try_format(csid, sd_state, fmt->pad, &fmt->format, fmt->which);
+	*format = fmt->format;
+
+	/* Propagate the format from sink to source pads */
+	if (fmt->pad == MSM_CSID_PAD_SINK) {
+		for (i = MSM_CSID_PAD_FIRST_SRC; i < MSM_CSID_PADS_NUM; ++i) {
+			format = __csid_get_format(csid, sd_state, i, fmt->which);
+
+			*format = fmt->format;
+			csid_try_format(csid, sd_state, i, format, fmt->which);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * csid_init_formats - Initialize formats on all pads
+ * @sd: CSID V4L2 subdevice
+ * @fh: V4L2 subdev file handle
+ *
+ * Initialize all pad formats with default values.
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+static int csid_init_formats(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct v4l2_subdev_format format = {
+		.pad = MSM_CSID_PAD_SINK,
+		.which = fh ? V4L2_SUBDEV_FORMAT_TRY :
+			      V4L2_SUBDEV_FORMAT_ACTIVE,
+		.format = {
+			.code = MEDIA_BUS_FMT_UYVY8_2X8,
+			.width = 1920,
+			.height = 1080
+		}
+	};
+
+	return csid_set_format(sd, fh ? fh->state : NULL, &format);
+}
+
+/*
+ * csid_set_test_pattern - Set test generator's pattern mode
+ * @csid: CSID device
+ * @value: desired test pattern mode
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+static int csid_set_test_pattern(struct csid_device *csid, s32 value)
+{
+	struct csid_testgen_config *tg = &csid->testgen;
+
+	/* If CSID is linked to CSIPHY, do not allow to enable test generator */
+	if (value && media_pad_remote_pad_first(&csid->pads[MSM_CSID_PAD_SINK]))
+		return -EBUSY;
+
+	tg->enabled = !!value;
+
+	return csid->ops->configure_testgen_pattern(csid, value);
+}
+
+/*
+ * csid_s_ctrl - Handle set control subdev method
+ * @ctrl: pointer to v4l2 control structure
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+static int csid_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct csid_device *csid = container_of(ctrl->handler,
+						struct csid_device, ctrls);
+	int ret = -EINVAL;
+
+	switch (ctrl->id) {
+	case V4L2_CID_TEST_PATTERN:
+		ret = csid_set_test_pattern(csid, ctrl->val);
+		break;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops csid_ctrl_ops = {
+	.s_ctrl = csid_s_ctrl,
+};
+
+/*
+ * msm_csid_subdev_init - Initialize CSID device structure and resources
+ * @csid: CSID device
+ * @res: CSID module resources table
+ * @id: CSID module id
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+int msm_csid_subdev_init(struct camss *camss, struct csid_device *csid,
+			 const struct resources *res, u8 id)
+{
+	struct device *dev = camss->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	int i, j;
+	int ret;
+
+	csid->camss = camss;
+	csid->id = id;
+
+	if (camss->version == CAMSS_8x16) {
+		csid->ops = &csid_ops_4_1;
+	} else if (camss->version == CAMSS_8x96 ||
+		   camss->version == CAMSS_660) {
+		csid->ops = &csid_ops_4_7;
+	} else if (camss->version == CAMSS_845 ||
+		   camss->version == CAMSS_8250) {
+		csid->ops = &csid_ops_gen2;
+	} else {
+		return -EINVAL;
+	}
+	csid->ops->subdev_init(csid);
+
+	/* Memory */
+
+	if (camss->version == CAMSS_8250) {
+		/* for titan 480, CSID registers are inside the VFE region,
+		 * between the VFE "top" and "bus" registers. this requires
+		 * VFE to be initialized before CSID
+		 */
+		if (id >= 2) /* VFE/CSID lite */
+			csid->base = camss->vfe[id].base + VFE_480_LITE_CSID_OFFSET;
+		else
+			csid->base = camss->vfe[id].base + VFE_480_CSID_OFFSET;
+	} else {
+		csid->base = devm_platform_ioremap_resource_byname(pdev, res->reg[0]);
+		if (IS_ERR(csid->base))
+			return PTR_ERR(csid->base);
+	}
+
+	/* Interrupt */
+
+	ret = platform_get_irq_byname(pdev, res->interrupt[0]);
+	if (ret < 0)
+		return ret;
+
+	csid->irq = ret;
+	snprintf(csid->irq_name, sizeof(csid->irq_name), "%s_%s%d",
+		 dev_name(dev), MSM_CSID_NAME, csid->id);
+	ret = devm_request_irq(dev, csid->irq, csid->ops->isr,
+			       IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN,
+			       csid->irq_name, csid);
+	if (ret < 0) {
+		dev_err(dev, "request_irq failed: %d\n", ret);
+		return ret;
+	}
+
+	/* Clocks */
+
+	csid->nclocks = 0;
+	while (res->clock[csid->nclocks])
+		csid->nclocks++;
+
+	csid->clock = devm_kcalloc(dev, csid->nclocks, sizeof(*csid->clock),
+				    GFP_KERNEL);
+	if (!csid->clock)
+		return -ENOMEM;
+
+	for (i = 0; i < csid->nclocks; i++) {
+		struct camss_clock *clock = &csid->clock[i];
+
+		clock->clk = devm_clk_get(dev, res->clock[i]);
+		if (IS_ERR(clock->clk))
+			return PTR_ERR(clock->clk);
+
+		clock->name = res->clock[i];
+
+		clock->nfreqs = 0;
+		while (res->clock_rate[i][clock->nfreqs])
+			clock->nfreqs++;
+
+		if (!clock->nfreqs) {
+			clock->freq = NULL;
+			continue;
+		}
+
+		clock->freq = devm_kcalloc(dev,
+					   clock->nfreqs,
+					   sizeof(*clock->freq),
+					   GFP_KERNEL);
+		if (!clock->freq)
+			return -ENOMEM;
+
+		for (j = 0; j < clock->nfreqs; j++)
+			clock->freq[j] = res->clock_rate[i][j];
+	}
+
+	/* Regulator */
+	for (i = 0; i < ARRAY_SIZE(res->regulators); i++) {
+		if (res->regulators[i])
+			csid->num_supplies++;
+	}
+
+	if (csid->num_supplies) {
+		csid->supplies = devm_kmalloc_array(camss->dev,
+						    csid->num_supplies,
+						    sizeof(*csid->supplies),
+						    GFP_KERNEL);
+		if (!csid->supplies)
+			return -ENOMEM;
+	}
+
+	for (i = 0; i < csid->num_supplies; i++)
+		csid->supplies[i].supply = res->regulators[i];
+
+	ret = devm_regulator_bulk_get(camss->dev, csid->num_supplies,
+				      csid->supplies);
+	if (ret)
+		return ret;
+
+	init_completion(&csid->reset_complete);
+
+	return 0;
+}
+
+/*
+ * msm_csid_get_csid_id - Get CSID HW module id
+ * @entity: Pointer to CSID media entity structure
+ * @id: Return CSID HW module id here
+ */
+void msm_csid_get_csid_id(struct media_entity *entity, u8 *id)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct csid_device *csid = v4l2_get_subdevdata(sd);
+
+	*id = csid->id;
+}
+
+/*
+ * csid_get_lane_assign - Calculate CSI2 lane assign configuration parameter
+ * @lane_cfg - CSI2 lane configuration
+ *
+ * Return lane assign
+ */
+static u32 csid_get_lane_assign(struct csiphy_lanes_cfg *lane_cfg)
+{
+	u32 lane_assign = 0;
+	int i;
+
+	for (i = 0; i < lane_cfg->num_data; i++)
+		lane_assign |= lane_cfg->data[i].pos << (i * 4);
+
+	return lane_assign;
+}
+
+/*
+ * csid_link_setup - Setup CSID connections
+ * @entity: Pointer to media entity structure
+ * @local: Pointer to local pad
+ * @remote: Pointer to remote pad
+ * @flags: Link flags
+ *
+ * Return 0 on success
+ */
+static int csid_link_setup(struct media_entity *entity,
+			   const struct media_pad *local,
+			   const struct media_pad *remote, u32 flags)
+{
+	if (flags & MEDIA_LNK_FL_ENABLED)
+		if (media_pad_remote_pad_first(local))
+			return -EBUSY;
+
+	if ((local->flags & MEDIA_PAD_FL_SINK) &&
+	    (flags & MEDIA_LNK_FL_ENABLED)) {
+		struct v4l2_subdev *sd;
+		struct csid_device *csid;
+		struct csiphy_device *csiphy;
+		struct csiphy_lanes_cfg *lane_cfg;
+
+		sd = media_entity_to_v4l2_subdev(entity);
+		csid = v4l2_get_subdevdata(sd);
+
+		/* If test generator is enabled */
+		/* do not allow a link from CSIPHY to CSID */
+		if (csid->testgen_mode->cur.val != 0)
+			return -EBUSY;
+
+		sd = media_entity_to_v4l2_subdev(remote->entity);
+		csiphy = v4l2_get_subdevdata(sd);
+
+		/* If a sensor is not linked to CSIPHY */
+		/* do no allow a link from CSIPHY to CSID */
+		if (!csiphy->cfg.csi2)
+			return -EPERM;
+
+		csid->phy.csiphy_id = csiphy->id;
+
+		lane_cfg = &csiphy->cfg.csi2->lane_cfg;
+		csid->phy.lane_cnt = lane_cfg->num_data;
+		csid->phy.lane_assign = csid_get_lane_assign(lane_cfg);
+	}
+	/* Decide which virtual channels to enable based on which source pads are enabled */
+	if (local->flags & MEDIA_PAD_FL_SOURCE) {
+		struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+		struct csid_device *csid = v4l2_get_subdevdata(sd);
+		struct device *dev = csid->camss->dev;
+
+		if (flags & MEDIA_LNK_FL_ENABLED)
+			csid->phy.en_vc |= BIT(local->index - 1);
+		else
+			csid->phy.en_vc &= ~BIT(local->index - 1);
+
+		csid->phy.need_vc_update = true;
+
+		dev_dbg(dev, "%s: Enabled CSID virtual channels mask 0x%x\n",
+			__func__, csid->phy.en_vc);
+	}
+
+	return 0;
+}
+
+static const struct v4l2_subdev_core_ops csid_core_ops = {
+	.s_power = csid_set_power,
+	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
+	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
+};
+
+static const struct v4l2_subdev_video_ops csid_video_ops = {
+	.s_stream = csid_set_stream,
+};
+
+static const struct v4l2_subdev_pad_ops csid_pad_ops = {
+	.enum_mbus_code = csid_enum_mbus_code,
+	.enum_frame_size = csid_enum_frame_size,
+	.get_fmt = csid_get_format,
+	.set_fmt = csid_set_format,
+};
+
+static const struct v4l2_subdev_ops csid_v4l2_ops = {
+	.core = &csid_core_ops,
+	.video = &csid_video_ops,
+	.pad = &csid_pad_ops,
+};
+
+static const struct v4l2_subdev_internal_ops csid_v4l2_internal_ops = {
+	.open = csid_init_formats,
+};
+
+static const struct media_entity_operations csid_media_ops = {
+	.link_setup = csid_link_setup,
+	.link_validate = v4l2_subdev_link_validate,
+};
+
+/*
+ * msm_csid_register_entity - Register subdev node for CSID module
+ * @csid: CSID device
+ * @v4l2_dev: V4L2 device
+ *
+ * Return 0 on success or a negative error code otherwise
+ */
+int msm_csid_register_entity(struct csid_device *csid,
+			     struct v4l2_device *v4l2_dev)
+{
+	struct v4l2_subdev *sd = &csid->subdev;
+	struct media_pad *pads = csid->pads;
+	struct device *dev = csid->camss->dev;
+	int i;
+	int ret;
+
+	v4l2_subdev_init(sd, &csid_v4l2_ops);
+	sd->internal_ops = &csid_v4l2_internal_ops;
+	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
+		     V4L2_SUBDEV_FL_HAS_EVENTS;
+	snprintf(sd->name, ARRAY_SIZE(sd->name), "%s%d",
+		 MSM_CSID_NAME, csid->id);
+	v4l2_set_subdevdata(sd, csid);
+
+	ret = v4l2_ctrl_handler_init(&csid->ctrls, 1);
+	if (ret < 0) {
+		dev_err(dev, "Failed to init ctrl handler: %d\n", ret);
+		return ret;
+	}
+
+	csid->testgen_mode = v4l2_ctrl_new_std_menu_items(&csid->ctrls,
+				&csid_ctrl_ops, V4L2_CID_TEST_PATTERN,
+				csid->testgen.nmodes, 0, 0,
+				csid->testgen.modes);
+
+	if (csid->ctrls.error) {
+		dev_err(dev, "Failed to init ctrl: %d\n", csid->ctrls.error);
+		ret = csid->ctrls.error;
+		goto free_ctrl;
+	}
+
+	csid->subdev.ctrl_handler = &csid->ctrls;
+
+	ret = csid_init_formats(sd, NULL);
+	if (ret < 0) {
+		dev_err(dev, "Failed to init format: %d\n", ret);
+		goto free_ctrl;
+	}
+
+	pads[MSM_CSID_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+	for (i = MSM_CSID_PAD_FIRST_SRC; i < MSM_CSID_PADS_NUM; ++i)
+		pads[i].flags = MEDIA_PAD_FL_SOURCE;
+
+	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+	sd->entity.ops = &csid_media_ops;
+	ret = media_entity_pads_init(&sd->entity, MSM_CSID_PADS_NUM, pads);
+	if (ret < 0) {
+		dev_err(dev, "Failed to init media entity: %d\n", ret);
+		goto free_ctrl;
+	}
+
+	ret = v4l2_device_register_subdev(v4l2_dev, sd);
+	if (ret < 0) {
+		dev_err(dev, "Failed to register subdev: %d\n", ret);
+		goto media_cleanup;
+	}
+
+	return 0;
+
+media_cleanup:
+	media_entity_cleanup(&sd->entity);
+free_ctrl:
+	v4l2_ctrl_handler_free(&csid->ctrls);
+
+	return ret;
+}
+
+/*
+ * msm_csid_unregister_entity - Unregister CSID module subdev node
+ * @csid: CSID device
+ */
+void msm_csid_unregister_entity(struct csid_device *csid)
+{
+	v4l2_device_unregister_subdev(&csid->subdev);
+	media_entity_cleanup(&csid->subdev.entity);
+	v4l2_ctrl_handler_free(&csid->ctrls);
+}