xref: /openbmc/linux/drivers/media/platform/qcom/camss/camss.c (revision 2f908577)

// SPDX-License-Identifier: GPL-2.0
/*
 * camss.c
 *
 * Qualcomm MSM Camera Subsystem - Core
 *
 * Copyright (c) 2015, The Linux Foundation. All rights reserved.
 * Copyright (C) 2015-2018 Linaro Ltd.
 */
#include <linux/clk.h>
#include <linux/media-bus-format.h>
#include <linux/media.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
#include <linux/slab.h>
#include <linux/videodev2.h>

#include <media/media-device.h>
#include <media/v4l2-async.h>
#include <media/v4l2-device.h>
#include <media/v4l2-mc.h>
#include <media/v4l2-fwnode.h>

#include "camss.h"

#define CAMSS_CLOCK_MARGIN_NUMERATOR 105
#define CAMSS_CLOCK_MARGIN_DENOMINATOR 100

static const struct resources csiphy_res_8x16[] = {
	/* CSIPHY0 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy0_timer" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000 } },
		.reg = { "csiphy0", "csiphy0_clk_mux" },
		.interrupt = { "csiphy0" }
	},

	/* CSIPHY1 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy1_timer" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000 } },
		.reg = { "csiphy1", "csiphy1_clk_mux" },
		.interrupt = { "csiphy1" }
	}
};

static const struct resources csid_res_8x16[] = {
	/* CSID0 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi0_ahb", "ahb",
			   "csi0", "csi0_phy", "csi0_pix", "csi0_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid0" },
		.interrupt = { "csid0" }
	},

	/* CSID1 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi1_ahb", "ahb",
			   "csi1", "csi1_phy", "csi1_pix", "csi1_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid1" },
		.interrupt = { "csid1" }
	},
};

static const struct resources_ispif ispif_res_8x16 = {
	/* ISPIF */
	.clock = { "top_ahb", "ahb", "ispif_ahb",
		   "csi0", "csi0_pix", "csi0_rdi",
		   "csi1", "csi1_pix", "csi1_rdi" },
	.clock_for_reset = { "vfe0", "csi_vfe0" },
	.reg = { "ispif", "csi_clk_mux" },
	.interrupt = "ispif"

};

static const struct resources vfe_res_8x16[] = {
	/* VFE0 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "vfe0", "csi_vfe0",
			   "vfe_ahb", "vfe_axi", "ahb" },
		.clock_rate = { { 0 },
				{ 50000000, 80000000, 100000000, 160000000,
				  177780000, 200000000, 266670000, 320000000,
				  400000000, 465000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "vfe0" },
		.interrupt = { "vfe0" }
	}
};

static const struct resources csiphy_res_8x96[] = {
	/* CSIPHY0 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy0_timer" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 } },
		.reg = { "csiphy0", "csiphy0_clk_mux" },
		.interrupt = { "csiphy0" }
	},

	/* CSIPHY1 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy1_timer" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 } },
		.reg = { "csiphy1", "csiphy1_clk_mux" },
		.interrupt = { "csiphy1" }
	},

	/* CSIPHY2 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy2_timer" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 } },
		.reg = { "csiphy2", "csiphy2_clk_mux" },
		.interrupt = { "csiphy2" }
	}
};

static const struct resources csid_res_8x96[] = {
	/* CSID0 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi0_ahb", "ahb",
			   "csi0", "csi0_phy", "csi0_pix", "csi0_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid0" },
		.interrupt = { "csid0" }
	},

	/* CSID1 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi1_ahb", "ahb",
			   "csi1", "csi1_phy", "csi1_pix", "csi1_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid1" },
		.interrupt = { "csid1" }
	},

	/* CSID2 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi2_ahb", "ahb",
			   "csi2", "csi2_phy", "csi2_pix", "csi2_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid2" },
		.interrupt = { "csid2" }
	},

	/* CSID3 */
	{
		.regulator = { "vdda" },
		.clock = { "top_ahb", "ispif_ahb", "csi3_ahb", "ahb",
			   "csi3", "csi3_phy", "csi3_pix", "csi3_rdi" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 266666667 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid3" },
		.interrupt = { "csid3" }
	}
};

static const struct resources_ispif ispif_res_8x96 = {
	/* ISPIF */
	.clock = { "top_ahb", "ahb", "ispif_ahb",
		   "csi0", "csi0_pix", "csi0_rdi",
		   "csi1", "csi1_pix", "csi1_rdi",
		   "csi2", "csi2_pix", "csi2_rdi",
		   "csi3", "csi3_pix", "csi3_rdi" },
	.clock_for_reset = { "vfe0", "csi_vfe0", "vfe1", "csi_vfe1" },
	.reg = { "ispif", "csi_clk_mux" },
	.interrupt = "ispif"
};

static const struct resources vfe_res_8x96[] = {
	/* VFE0 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ahb", "vfe0", "csi_vfe0", "vfe_ahb",
			   "vfe0_ahb", "vfe_axi", "vfe0_stream"},
		.clock_rate = { { 0 },
				{ 0 },
				{ 75000000, 100000000, 300000000,
				  320000000, 480000000, 600000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "vfe0" },
		.interrupt = { "vfe0" }
	},

	/* VFE1 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ahb", "vfe1", "csi_vfe1", "vfe_ahb",
			   "vfe1_ahb", "vfe_axi", "vfe1_stream"},
		.clock_rate = { { 0 },
				{ 0 },
				{ 75000000, 100000000, 300000000,
				  320000000, 480000000, 600000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "vfe1" },
		.interrupt = { "vfe1" }
	}
};

static const struct resources csiphy_res_660[] = {
	/* CSIPHY0 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy0_timer",
			   "csi0_phy", "csiphy_ahb2crif" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 269333333 },
				{ 0 } },
		.reg = { "csiphy0", "csiphy0_clk_mux" },
		.interrupt = { "csiphy0" }
	},

	/* CSIPHY1 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy1_timer",
			   "csi1_phy", "csiphy_ahb2crif" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 269333333 },
				{ 0 } },
		.reg = { "csiphy1", "csiphy1_clk_mux" },
		.interrupt = { "csiphy1" }
	},

	/* CSIPHY2 */
	{
		.regulator = { NULL },
		.clock = { "top_ahb", "ispif_ahb", "ahb", "csiphy2_timer",
			   "csi2_phy", "csiphy_ahb2crif" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 269333333 },
				{ 0 } },
		.reg = { "csiphy2", "csiphy2_clk_mux" },
		.interrupt = { "csiphy2" }
	}
};

static const struct resources csid_res_660[] = {
	/* CSID0 */
	{
		.regulator = { "vdda", "vdd_sec" },
		.clock = { "top_ahb", "ispif_ahb", "csi0_ahb", "ahb",
			   "csi0", "csi0_phy", "csi0_pix", "csi0_rdi",
			   "cphy_csid0" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 310000000,
				  404000000, 465000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid0" },
		.interrupt = { "csid0" }
	},

	/* CSID1 */
	{
		.regulator = { "vdda", "vdd_sec" },
		.clock = { "top_ahb", "ispif_ahb", "csi1_ahb", "ahb",
			   "csi1", "csi1_phy", "csi1_pix", "csi1_rdi",
			   "cphy_csid1" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 310000000,
				  404000000, 465000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid1" },
		.interrupt = { "csid1" }
	},

	/* CSID2 */
	{
		.regulator = { "vdda", "vdd_sec" },
		.clock = { "top_ahb", "ispif_ahb", "csi2_ahb", "ahb",
			   "csi2", "csi2_phy", "csi2_pix", "csi2_rdi",
			   "cphy_csid2" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 310000000,
				  404000000, 465000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid2" },
		.interrupt = { "csid2" }
	},

	/* CSID3 */
	{
		.regulator = { "vdda", "vdd_sec" },
		.clock = { "top_ahb", "ispif_ahb", "csi3_ahb", "ahb",
			   "csi3", "csi3_phy", "csi3_pix", "csi3_rdi",
			   "cphy_csid3" },
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 100000000, 200000000, 310000000,
				  404000000, 465000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "csid3" },
		.interrupt = { "csid3" }
	}
};

static const struct resources_ispif ispif_res_660 = {
	/* ISPIF */
	.clock = { "top_ahb", "ahb", "ispif_ahb",
		   "csi0", "csi0_pix", "csi0_rdi",
		   "csi1", "csi1_pix", "csi1_rdi",
		   "csi2", "csi2_pix", "csi2_rdi",
		   "csi3", "csi3_pix", "csi3_rdi" },
	.clock_for_reset = { "vfe0", "csi_vfe0", "vfe1", "csi_vfe1" },
	.reg = { "ispif", "csi_clk_mux" },
	.interrupt = "ispif"
};

static const struct resources vfe_res_660[] = {
	/* VFE0 */
	{
		.regulator = { NULL },
		.clock = { "throttle_axi", "top_ahb", "ahb", "vfe0",
			   "csi_vfe0", "vfe_ahb", "vfe0_ahb", "vfe_axi",
			   "vfe0_stream"},
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 120000000, 200000000, 256000000,
				  300000000, 404000000, 480000000,
				  540000000, 576000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "vfe0" },
		.interrupt = { "vfe0" }
	},

	/* VFE1 */
	{
		.regulator = { NULL },
		.clock = { "throttle_axi", "top_ahb", "ahb", "vfe1",
			   "csi_vfe1", "vfe_ahb", "vfe1_ahb", "vfe_axi",
			   "vfe1_stream"},
		.clock_rate = { { 0 },
				{ 0 },
				{ 0 },
				{ 120000000, 200000000, 256000000,
				  300000000, 404000000, 480000000,
				  540000000, 576000000 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 },
				{ 0 } },
		.reg = { "vfe1" },
		.interrupt = { "vfe1" }
	}
};

/*
 * camss_add_clock_margin - Add margin to clock frequency rate
 * @rate: Clock frequency rate
 *
 * When making calculations with physical clock frequency values
 * some safety margin must be added. Add it.
 */
inline void camss_add_clock_margin(u64 *rate)
{
	*rate *= CAMSS_CLOCK_MARGIN_NUMERATOR;
	*rate = div_u64(*rate, CAMSS_CLOCK_MARGIN_DENOMINATOR);
}

/*
 * camss_enable_clocks - Enable multiple clocks
 * @nclocks: Number of clocks in clock array
 * @clock: Clock array
 * @dev: Device
 *
 * Return 0 on success or a negative error code otherwise
 */
int camss_enable_clocks(int nclocks, struct camss_clock *clock,
			struct device *dev)
{
	int ret;
	int i;

	for (i = 0; i < nclocks; i++) {
		ret = clk_prepare_enable(clock[i].clk);
		if (ret) {
			dev_err(dev, "clock enable failed: %d\n", ret);
			goto error;
		}
	}

	return 0;

error:
	for (i--; i >= 0; i--)
		clk_disable_unprepare(clock[i].clk);

	return ret;
}

/*
 * camss_disable_clocks - Disable multiple clocks
 * @nclocks: Number of clocks in clock array
 * @clock: Clock array
 */
void camss_disable_clocks(int nclocks, struct camss_clock *clock)
{
	int i;

	for (i = nclocks - 1; i >= 0; i--)
		clk_disable_unprepare(clock[i].clk);
}

/*
 * camss_find_sensor - Find a linked media entity which represents a sensor
 * @entity: Media entity to start searching from
 *
 * Return a pointer to sensor media entity or NULL if not found
 */
struct media_entity *camss_find_sensor(struct media_entity *entity)
{
	struct media_pad *pad;

	while (1) {
		pad = &entity->pads[0];
		if (!(pad->flags & MEDIA_PAD_FL_SINK))
			return NULL;

		pad = media_entity_remote_pad(pad);
		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
			return NULL;

		entity = pad->entity;

		if (entity->function == MEDIA_ENT_F_CAM_SENSOR)
			return entity;
	}
}

/**
 * camss_get_link_freq - Get link frequency from sensor
 * @entity: Media entity in the current pipeline
 * @bpp: Number of bits per pixel for the current format
 * @lanes: Number of lanes in the link to the sensor
 *
 * Return link frequency on success or a negative error code otherwise
 */
s64 camss_get_link_freq(struct media_entity *entity, unsigned int bpp,
			unsigned int lanes)
{
	struct media_entity *sensor;
	struct v4l2_subdev *subdev;

	sensor = camss_find_sensor(entity);
	if (!sensor)
		return -ENODEV;

	subdev = media_entity_to_v4l2_subdev(sensor);

	return v4l2_get_link_freq(subdev->ctrl_handler, bpp, 2 * lanes);
}

/*
 * camss_get_pixel_clock - Get pixel clock rate from sensor
 * @entity: Media entity in the current pipeline
 * @pixel_clock: Received pixel clock value
 *
 * Return 0 on success or a negative error code otherwise
 */
int camss_get_pixel_clock(struct media_entity *entity, u64 *pixel_clock)
{
	struct media_entity *sensor;
	struct v4l2_subdev *subdev;
	struct v4l2_ctrl *ctrl;

	sensor = camss_find_sensor(entity);
	if (!sensor)
		return -ENODEV;

	subdev = media_entity_to_v4l2_subdev(sensor);

	ctrl = v4l2_ctrl_find(subdev->ctrl_handler, V4L2_CID_PIXEL_RATE);

	if (!ctrl)
		return -EINVAL;

	*pixel_clock = v4l2_ctrl_g_ctrl_int64(ctrl);

	return 0;
}

int camss_pm_domain_on(struct camss *camss, int id)
{
	if (camss->version == CAMSS_8x96 ||
	    camss->version == CAMSS_660) {
		camss->genpd_link[id] = device_link_add(camss->dev,
				camss->genpd[id], DL_FLAG_STATELESS |
				DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);

		if (!camss->genpd_link[id])
			return -EINVAL;
	}

	return 0;
}

void camss_pm_domain_off(struct camss *camss, int id)
{
	if (camss->version == CAMSS_8x96 ||
	    camss->version == CAMSS_660)
		device_link_del(camss->genpd_link[id]);
}

/*
 * camss_of_parse_endpoint_node - Parse port endpoint node
 * @dev: Device
 * @node: Device node to be parsed
 * @csd: Parsed data from port endpoint node
 *
 * Return 0 on success or a negative error code on failure
 */
static int camss_of_parse_endpoint_node(struct device *dev,
					struct device_node *node,
					struct camss_async_subdev *csd)
{
	struct csiphy_lanes_cfg *lncfg = &csd->interface.csi2.lane_cfg;
	struct v4l2_fwnode_bus_mipi_csi2 *mipi_csi2;
	struct v4l2_fwnode_endpoint vep = { { 0 } };
	unsigned int i;

	v4l2_fwnode_endpoint_parse(of_fwnode_handle(node), &vep);

	csd->interface.csiphy_id = vep.base.port;

	mipi_csi2 = &vep.bus.mipi_csi2;
	lncfg->clk.pos = mipi_csi2->clock_lane;
	lncfg->clk.pol = mipi_csi2->lane_polarities[0];
	lncfg->num_data = mipi_csi2->num_data_lanes;

	lncfg->data = devm_kcalloc(dev,
				   lncfg->num_data, sizeof(*lncfg->data),
				   GFP_KERNEL);
	if (!lncfg->data)
		return -ENOMEM;

	for (i = 0; i < lncfg->num_data; i++) {
		lncfg->data[i].pos = mipi_csi2->data_lanes[i];
		lncfg->data[i].pol = mipi_csi2->lane_polarities[i + 1];
	}

	return 0;
}

/*
 * camss_of_parse_ports - Parse ports node
 * @dev: Device
 * @notifier: v4l2_device notifier data
 *
 * Return number of "port" nodes found in "ports" node
 */
static int camss_of_parse_ports(struct camss *camss)
{
	struct device *dev = camss->dev;
	struct device_node *node = NULL;
	struct device_node *remote = NULL;
	int ret, num_subdevs = 0;

	for_each_endpoint_of_node(dev->of_node, node) {
		struct camss_async_subdev *csd;

		if (!of_device_is_available(node))
			continue;

		remote = of_graph_get_remote_port_parent(node);
		if (!remote) {
			dev_err(dev, "Cannot get remote parent\n");
			ret = -EINVAL;
			goto err_cleanup;
		}

		csd = v4l2_async_notifier_add_fwnode_subdev(
			&camss->notifier, of_fwnode_handle(remote),
			struct camss_async_subdev);
		of_node_put(remote);
		if (IS_ERR(csd)) {
			ret = PTR_ERR(csd);
			goto err_cleanup;
		}

		ret = camss_of_parse_endpoint_node(dev, node, csd);
		if (ret < 0)
			goto err_cleanup;

		num_subdevs++;
	}

	return num_subdevs;

err_cleanup:
	of_node_put(node);
	return ret;
}

/*
 * camss_init_subdevices - Initialize subdev structures and resources
 * @camss: CAMSS device
 *
 * Return 0 on success or a negative error code on failure
 */
static int camss_init_subdevices(struct camss *camss)
{
	const struct resources *csiphy_res;
	const struct resources *csid_res;
	const struct resources_ispif *ispif_res;
	const struct resources *vfe_res;
	unsigned int i;
	int ret;

	if (camss->version == CAMSS_8x16) {
		csiphy_res = csiphy_res_8x16;
		csid_res = csid_res_8x16;
		ispif_res = &ispif_res_8x16;
		vfe_res = vfe_res_8x16;
	} else if (camss->version == CAMSS_8x96) {
		csiphy_res = csiphy_res_8x96;
		csid_res = csid_res_8x96;
		ispif_res = &ispif_res_8x96;
		vfe_res = vfe_res_8x96;
	} else if (camss->version == CAMSS_660) {
		csiphy_res = csiphy_res_660;
		csid_res = csid_res_660;
		ispif_res = &ispif_res_660;
		vfe_res = vfe_res_660;
	} else {
		return -EINVAL;
	}

	for (i = 0; i < camss->csiphy_num; i++) {
		ret = msm_csiphy_subdev_init(camss, &camss->csiphy[i],
					     &csiphy_res[i], i);
		if (ret < 0) {
			dev_err(camss->dev,
				"Failed to init csiphy%d sub-device: %d\n",
				i, ret);
			return ret;
		}
	}

	for (i = 0; i < camss->csid_num; i++) {
		ret = msm_csid_subdev_init(camss, &camss->csid[i],
					   &csid_res[i], i);
		if (ret < 0) {
			dev_err(camss->dev,
				"Failed to init csid%d sub-device: %d\n",
				i, ret);
			return ret;
		}
	}

	ret = msm_ispif_subdev_init(&camss->ispif, ispif_res);
	if (ret < 0) {
		dev_err(camss->dev, "Failed to init ispif sub-device: %d\n",
			ret);
		return ret;
	}

	for (i = 0; i < camss->vfe_num; i++) {
		ret = msm_vfe_subdev_init(camss, &camss->vfe[i],
					  &vfe_res[i], i);
		if (ret < 0) {
			dev_err(camss->dev,
				"Fail to init vfe%d sub-device: %d\n", i, ret);
			return ret;
		}
	}

	return 0;
}

/*
 * camss_register_entities - Register subdev nodes and create links
 * @camss: CAMSS device
 *
 * Return 0 on success or a negative error code on failure
 */
static int camss_register_entities(struct camss *camss)
{
	int i, j, k;
	int ret;

	for (i = 0; i < camss->csiphy_num; i++) {
		ret = msm_csiphy_register_entity(&camss->csiphy[i],
						 &camss->v4l2_dev);
		if (ret < 0) {
			dev_err(camss->dev,
				"Failed to register csiphy%d entity: %d\n",
				i, ret);
			goto err_reg_csiphy;
		}
	}

	for (i = 0; i < camss->csid_num; i++) {
		ret = msm_csid_register_entity(&camss->csid[i],
					       &camss->v4l2_dev);
		if (ret < 0) {
			dev_err(camss->dev,
				"Failed to register csid%d entity: %d\n",
				i, ret);
			goto err_reg_csid;
		}
	}

	ret = msm_ispif_register_entities(&camss->ispif, &camss->v4l2_dev);
	if (ret < 0) {
		dev_err(camss->dev, "Failed to register ispif entities: %d\n",
			ret);
		goto err_reg_ispif;
	}

	for (i = 0; i < camss->vfe_num; i++) {
		ret = msm_vfe_register_entities(&camss->vfe[i],
						&camss->v4l2_dev);
		if (ret < 0) {
			dev_err(camss->dev,
				"Failed to register vfe%d entities: %d\n",
				i, ret);
			goto err_reg_vfe;
		}
	}

	for (i = 0; i < camss->csiphy_num; i++) {
		for (j = 0; j < camss->csid_num; j++) {
			ret = media_create_pad_link(
				&camss->csiphy[i].subdev.entity,
				MSM_CSIPHY_PAD_SRC,
				&camss->csid[j].subdev.entity,
				MSM_CSID_PAD_SINK,
				0);
			if (ret < 0) {
				dev_err(camss->dev,
					"Failed to link %s->%s entities: %d\n",
					camss->csiphy[i].subdev.entity.name,
					camss->csid[j].subdev.entity.name,
					ret);
				goto err_link;
			}
		}
	}

	for (i = 0; i < camss->csid_num; i++) {
		for (j = 0; j < camss->ispif.line_num; j++) {
			ret = media_create_pad_link(
				&camss->csid[i].subdev.entity,
				MSM_CSID_PAD_SRC,
				&camss->ispif.line[j].subdev.entity,
				MSM_ISPIF_PAD_SINK,
				0);
			if (ret < 0) {
				dev_err(camss->dev,
					"Failed to link %s->%s entities: %d\n",
					camss->csid[i].subdev.entity.name,
					camss->ispif.line[j].subdev.entity.name,
					ret);
				goto err_link;
			}
		}
	}

	for (i = 0; i < camss->ispif.line_num; i++)
		for (k = 0; k < camss->vfe_num; k++)
			for (j = 0; j < ARRAY_SIZE(camss->vfe[k].line); j++) {
				ret = media_create_pad_link(
					&camss->ispif.line[i].subdev.entity,
					MSM_ISPIF_PAD_SRC,
					&camss->vfe[k].line[j].subdev.entity,
					MSM_VFE_PAD_SINK,
					0);
				if (ret < 0) {
					dev_err(camss->dev,
						"Failed to link %s->%s entities: %d\n",
						camss->ispif.line[i].subdev.entity.name,
						camss->vfe[k].line[j].subdev.entity.name,
						ret);
					goto err_link;
				}
			}

	return 0;

err_link:
	i = camss->vfe_num;
err_reg_vfe:
	for (i--; i >= 0; i--)
		msm_vfe_unregister_entities(&camss->vfe[i]);

	msm_ispif_unregister_entities(&camss->ispif);
err_reg_ispif:

	i = camss->csid_num;
err_reg_csid:
	for (i--; i >= 0; i--)
		msm_csid_unregister_entity(&camss->csid[i]);

	i = camss->csiphy_num;
err_reg_csiphy:
	for (i--; i >= 0; i--)
		msm_csiphy_unregister_entity(&camss->csiphy[i]);

	return ret;
}

/*
 * camss_unregister_entities - Unregister subdev nodes
 * @camss: CAMSS device
 *
 * Return 0 on success or a negative error code on failure
 */
static void camss_unregister_entities(struct camss *camss)
{
	unsigned int i;

	for (i = 0; i < camss->csiphy_num; i++)
		msm_csiphy_unregister_entity(&camss->csiphy[i]);

	for (i = 0; i < camss->csid_num; i++)
		msm_csid_unregister_entity(&camss->csid[i]);

	msm_ispif_unregister_entities(&camss->ispif);

	for (i = 0; i < camss->vfe_num; i++)
		msm_vfe_unregister_entities(&camss->vfe[i]);
}

static int camss_subdev_notifier_bound(struct v4l2_async_notifier *async,
				       struct v4l2_subdev *subdev,
				       struct v4l2_async_subdev *asd)
{
	struct camss *camss = container_of(async, struct camss, notifier);
	struct camss_async_subdev *csd =
		container_of(asd, struct camss_async_subdev, asd);
	u8 id = csd->interface.csiphy_id;
	struct csiphy_device *csiphy = &camss->csiphy[id];

	csiphy->cfg.csi2 = &csd->interface.csi2;
	subdev->host_priv = csiphy;

	return 0;
}

static int camss_subdev_notifier_complete(struct v4l2_async_notifier *async)
{
	struct camss *camss = container_of(async, struct camss, notifier);
	struct v4l2_device *v4l2_dev = &camss->v4l2_dev;
	struct v4l2_subdev *sd;
	int ret;

	list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
		if (sd->host_priv) {
			struct media_entity *sensor = &sd->entity;
			struct csiphy_device *csiphy =
					(struct csiphy_device *) sd->host_priv;
			struct media_entity *input = &csiphy->subdev.entity;
			unsigned int i;

			for (i = 0; i < sensor->num_pads; i++) {
				if (sensor->pads[i].flags & MEDIA_PAD_FL_SOURCE)
					break;
			}
			if (i == sensor->num_pads) {
				dev_err(camss->dev,
					"No source pad in external entity\n");
				return -EINVAL;
			}

			ret = media_create_pad_link(sensor, i,
				input, MSM_CSIPHY_PAD_SINK,
				MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
			if (ret < 0) {
				dev_err(camss->dev,
					"Failed to link %s->%s entities: %d\n",
					sensor->name, input->name, ret);
				return ret;
			}
		}
	}

	ret = v4l2_device_register_subdev_nodes(&camss->v4l2_dev);
	if (ret < 0)
		return ret;

	return media_device_register(&camss->media_dev);
}

static const struct v4l2_async_notifier_operations camss_subdev_notifier_ops = {
	.bound = camss_subdev_notifier_bound,
	.complete = camss_subdev_notifier_complete,
};

static const struct media_device_ops camss_media_ops = {
	.link_notify = v4l2_pipeline_link_notify,
};

/*
 * camss_probe - Probe CAMSS platform device
 * @pdev: Pointer to CAMSS platform device
 *
 * Return 0 on success or a negative error code on failure
 */
static int camss_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct camss *camss;
	int num_subdevs, ret;

	camss = kzalloc(sizeof(*camss), GFP_KERNEL);
	if (!camss)
		return -ENOMEM;

	atomic_set(&camss->ref_count, 0);
	camss->dev = dev;
	platform_set_drvdata(pdev, camss);

	if (of_device_is_compatible(dev->of_node, "qcom,msm8916-camss")) {
		camss->version = CAMSS_8x16;
		camss->csiphy_num = 2;
		camss->csid_num = 2;
		camss->vfe_num = 1;
	} else if (of_device_is_compatible(dev->of_node,
					   "qcom,msm8996-camss")) {
		camss->version = CAMSS_8x96;
		camss->csiphy_num = 3;
		camss->csid_num = 4;
		camss->vfe_num = 2;
	} else if (of_device_is_compatible(dev->of_node,
					   "qcom,sdm660-camss")) {
		camss->version = CAMSS_660;
		camss->csiphy_num = 3;
		camss->csid_num = 4;
		camss->vfe_num = 2;
	} else {
		ret = -EINVAL;
		goto err_free;
	}

	camss->csiphy = devm_kcalloc(dev, camss->csiphy_num,
				     sizeof(*camss->csiphy), GFP_KERNEL);
	if (!camss->csiphy) {
		ret = -ENOMEM;
		goto err_free;
	}

	camss->csid = devm_kcalloc(dev, camss->csid_num, sizeof(*camss->csid),
				   GFP_KERNEL);
	if (!camss->csid) {
		ret = -ENOMEM;
		goto err_free;
	}

	camss->vfe = devm_kcalloc(dev, camss->vfe_num, sizeof(*camss->vfe),
				  GFP_KERNEL);
	if (!camss->vfe) {
		ret = -ENOMEM;
		goto err_free;
	}

	v4l2_async_notifier_init(&camss->notifier);

	num_subdevs = camss_of_parse_ports(camss);
	if (num_subdevs < 0) {
		ret = num_subdevs;
		goto err_cleanup;
	}

	ret = camss_init_subdevices(camss);
	if (ret < 0)
		goto err_cleanup;

	ret = dma_set_mask_and_coherent(dev, 0xffffffff);
	if (ret)
		goto err_cleanup;

	camss->media_dev.dev = camss->dev;
	strscpy(camss->media_dev.model, "Qualcomm Camera Subsystem",
		sizeof(camss->media_dev.model));
	camss->media_dev.ops = &camss_media_ops;
	media_device_init(&camss->media_dev);

	camss->v4l2_dev.mdev = &camss->media_dev;
	ret = v4l2_device_register(camss->dev, &camss->v4l2_dev);
	if (ret < 0) {
		dev_err(dev, "Failed to register V4L2 device: %d\n", ret);
		goto err_cleanup;
	}

	ret = camss_register_entities(camss);
	if (ret < 0)
		goto err_register_entities;

	if (num_subdevs) {
		camss->notifier.ops = &camss_subdev_notifier_ops;

		ret = v4l2_async_notifier_register(&camss->v4l2_dev,
						   &camss->notifier);
		if (ret) {
			dev_err(dev,
				"Failed to register async subdev nodes: %d\n",
				ret);
			goto err_register_subdevs;
		}
	} else {
		ret = v4l2_device_register_subdev_nodes(&camss->v4l2_dev);
		if (ret < 0) {
			dev_err(dev, "Failed to register subdev nodes: %d\n",
				ret);
			goto err_register_subdevs;
		}

		ret = media_device_register(&camss->media_dev);
		if (ret < 0) {
			dev_err(dev, "Failed to register media device: %d\n",
				ret);
			goto err_register_subdevs;
		}
	}

	if (camss->version == CAMSS_8x96 ||
	    camss->version == CAMSS_660) {
		camss->genpd[PM_DOMAIN_VFE0] = dev_pm_domain_attach_by_id(
						camss->dev, PM_DOMAIN_VFE0);
		if (IS_ERR(camss->genpd[PM_DOMAIN_VFE0]))
			return PTR_ERR(camss->genpd[PM_DOMAIN_VFE0]);

		camss->genpd[PM_DOMAIN_VFE1] = dev_pm_domain_attach_by_id(
						camss->dev, PM_DOMAIN_VFE1);
		if (IS_ERR(camss->genpd[PM_DOMAIN_VFE1])) {
			dev_pm_domain_detach(camss->genpd[PM_DOMAIN_VFE0],
					     true);
			return PTR_ERR(camss->genpd[PM_DOMAIN_VFE1]);
		}
	}

	pm_runtime_enable(dev);

	return 0;

err_register_subdevs:
	camss_unregister_entities(camss);
err_register_entities:
	v4l2_device_unregister(&camss->v4l2_dev);
err_cleanup:
	v4l2_async_notifier_cleanup(&camss->notifier);
err_free:
	kfree(camss);

	return ret;
}

void camss_delete(struct camss *camss)
{
	v4l2_device_unregister(&camss->v4l2_dev);
	media_device_unregister(&camss->media_dev);
	media_device_cleanup(&camss->media_dev);

	pm_runtime_disable(camss->dev);

	if (camss->version == CAMSS_8x96 ||
	    camss->version == CAMSS_660) {
		dev_pm_domain_detach(camss->genpd[PM_DOMAIN_VFE0], true);
		dev_pm_domain_detach(camss->genpd[PM_DOMAIN_VFE1], true);
	}

	kfree(camss);
}

/*
 * camss_remove - Remove CAMSS platform device
 * @pdev: Pointer to CAMSS platform device
 *
 * Always returns 0.
 */
static int camss_remove(struct platform_device *pdev)
{
	struct camss *camss = platform_get_drvdata(pdev);

	v4l2_async_notifier_unregister(&camss->notifier);
	v4l2_async_notifier_cleanup(&camss->notifier);
	camss_unregister_entities(camss);

	if (atomic_read(&camss->ref_count) == 0)
		camss_delete(camss);

	return 0;
}

static const struct of_device_id camss_dt_match[] = {
	{ .compatible = "qcom,msm8916-camss" },
	{ .compatible = "qcom,msm8996-camss" },
	{ .compatible = "qcom,sdm660-camss" },
	{ }
};

MODULE_DEVICE_TABLE(of, camss_dt_match);

static int __maybe_unused camss_runtime_suspend(struct device *dev)
{
	return 0;
}

static int __maybe_unused camss_runtime_resume(struct device *dev)
{
	return 0;
}

static const struct dev_pm_ops camss_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
				pm_runtime_force_resume)
	SET_RUNTIME_PM_OPS(camss_runtime_suspend, camss_runtime_resume, NULL)
};

static struct platform_driver qcom_camss_driver = {
	.probe = camss_probe,
	.remove = camss_remove,
	.driver = {
		.name = "qcom-camss",
		.of_match_table = camss_dt_match,
		.pm = &camss_pm_ops,
	},
};

module_platform_driver(qcom_camss_driver);

MODULE_ALIAS("platform:qcom-camss");
MODULE_DESCRIPTION("Qualcomm Camera Subsystem driver");
MODULE_AUTHOR("Todor Tomov <todor.tomov@linaro.org>");
MODULE_LICENSE("GPL v2");