Re: [RFC PATCH v1 4/5] media: tegra: Add Tegra Video input driver for Tegra210

["Hans Verkuil (hansverk)" <hansverk@cisco.com>]

Hi Sowjanya,

Thank you very much for working on this! Much appreciated.

On 1/28/20 7:23 PM, Sowjanya Komatineni wrote:
> Tegra210 contains a powerful Video Input (VI) hardware controller
> which can support up to 6 MIPI CSI camera sensors.
> 
> Each Tegra CSI port can be one-to-one mapped to VI channel and can
> capture from an external camera sensor connected to CSI or from
> built-in test pattern generator.
> 
> Tegra210 supports built-in test pattern generator from CSI to VI.
> 
> This patch adds a V4L2 media controller and capture driver support
> for Tegra210 built-in CSI to VI test pattern generator.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  drivers/staging/media/Kconfig               |   2 +
>  drivers/staging/media/Makefile              |   1 +
>  drivers/staging/media/tegra/Kconfig         |  12 +
>  drivers/staging/media/tegra/Makefile        |  11 +
>  drivers/staging/media/tegra/TODO            |  10 +
>  drivers/staging/media/tegra/csi.h           | 111 +++++
>  drivers/staging/media/tegra/csi2_fops.c     | 335 +++++++++++++++
>  drivers/staging/media/tegra/csi2_fops.h     |  15 +

These three files...

>  drivers/staging/media/tegra/host1x-video.c  | 120 ++++++
>  drivers/staging/media/tegra/host1x-video.h  |  33 ++
>  drivers/staging/media/tegra/mc_common.h     | 131 ++++++

...and this one are a bit too generic. It is good practice to prefix headers
with something unique, e.g. tegra-csi.h etc.

For example, sunxi has sun6i_csi.h and sun4i_csi.h.

>  drivers/staging/media/tegra/tegra-channel.c | 628 ++++++++++++++++++++++++++++
>  drivers/staging/media/tegra/tegra-core.c    | 111 +++++
>  drivers/staging/media/tegra/tegra-core.h    | 125 ++++++
>  drivers/staging/media/tegra/tegra-csi.c     | 380 +++++++++++++++++
>  drivers/staging/media/tegra/tegra-vi.c      | 351 ++++++++++++++++
>  drivers/staging/media/tegra/tegra-vi.h      | 101 +++++
>  drivers/staging/media/tegra/vi2_fops.c      | 364 ++++++++++++++++
>  drivers/staging/media/tegra/vi2_fops.h      |  15 +
>  drivers/staging/media/tegra/vi2_formats.h   | 119 ++++++
>  drivers/staging/media/tegra/vi2_registers.h | 194 +++++++++
>  21 files changed, 3169 insertions(+)
>  create mode 100644 drivers/staging/media/tegra/Kconfig
>  create mode 100644 drivers/staging/media/tegra/Makefile
>  create mode 100644 drivers/staging/media/tegra/TODO
>  create mode 100644 drivers/staging/media/tegra/csi.h
>  create mode 100644 drivers/staging/media/tegra/csi2_fops.c
>  create mode 100644 drivers/staging/media/tegra/csi2_fops.h
>  create mode 100644 drivers/staging/media/tegra/host1x-video.c
>  create mode 100644 drivers/staging/media/tegra/host1x-video.h
>  create mode 100644 drivers/staging/media/tegra/mc_common.h
>  create mode 100644 drivers/staging/media/tegra/tegra-channel.c
>  create mode 100644 drivers/staging/media/tegra/tegra-core.c
>  create mode 100644 drivers/staging/media/tegra/tegra-core.h
>  create mode 100644 drivers/staging/media/tegra/tegra-csi.c
>  create mode 100644 drivers/staging/media/tegra/tegra-vi.c
>  create mode 100644 drivers/staging/media/tegra/tegra-vi.h
>  create mode 100644 drivers/staging/media/tegra/vi2_fops.c
>  create mode 100644 drivers/staging/media/tegra/vi2_fops.h
>  create mode 100644 drivers/staging/media/tegra/vi2_formats.h
>  create mode 100644 drivers/staging/media/tegra/vi2_registers.h
> 
> diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
> index c394abffea86..e367030d4407 100644
> --- a/drivers/staging/media/Kconfig
> +++ b/drivers/staging/media/Kconfig
> @@ -34,6 +34,8 @@ source "drivers/staging/media/sunxi/Kconfig"
>  
>  source "drivers/staging/media/tegra-vde/Kconfig"
>  
> +source "drivers/staging/media/tegra/Kconfig"
> +
>  source "drivers/staging/media/ipu3/Kconfig"
>  
>  source "drivers/staging/media/soc_camera/Kconfig"
> diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
> index ea9fce8014bb..67a22ac709e8 100644
> --- a/drivers/staging/media/Makefile
> +++ b/drivers/staging/media/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_VIDEO_IPU3_IMGU)	+= ipu3/
>  obj-$(CONFIG_SOC_CAMERA)	+= soc_camera/
>  obj-$(CONFIG_PHY_ROCKCHIP_DPHY_RX0)	+= phy-rockchip-dphy-rx0/
>  obj-$(CONFIG_VIDEO_ROCKCHIP_ISP1)	+= rkisp1/
> +obj-$(CONFIG_VIDEO_TEGRA)	+= tegra/
> diff --git a/drivers/staging/media/tegra/Kconfig b/drivers/staging/media/tegra/Kconfig
> new file mode 100644
> index 000000000000..443b99f2e2c9
> --- /dev/null
> +++ b/drivers/staging/media/tegra/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config VIDEO_TEGRA
> +	tristate "NVIDIA Tegra VI driver"
> +	depends on ARCH_TEGRA || (ARM && COMPILE_TEST)
> +	depends on COMMON_CLK
> +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
> +	depends on MEDIA_CONTROLLER
> +	select TEGRA_HOST1X
> +	select VIDEOBUF2_DMA_CONTIG
> +	select V4L2_FWNODE
> +	help
> +	  Say yes here to enable support for Tegra video input hardware
> diff --git a/drivers/staging/media/tegra/Makefile b/drivers/staging/media/tegra/Makefile
> new file mode 100644
> index 000000000000..003d23444d49
> --- /dev/null
> +++ b/drivers/staging/media/tegra/Makefile
> @@ -0,0 +1,11 @@
> +# SPDX-License-Identifier: GPL-2.0
> +tegra-video-y := \
> +		host1x-video.o \
> +		tegra-channel.o \
> +		tegra-core.o \
> +		csi2_fops.o \
> +		vi2_fops.o \
> +		tegra-vi.o \
> +		tegra-csi.o
> +
> +obj-$(CONFIG_VIDEO_TEGRA) += tegra-video.o
> diff --git a/drivers/staging/media/tegra/TODO b/drivers/staging/media/tegra/TODO
> new file mode 100644
> index 000000000000..d7d64b13535e
> --- /dev/null
> +++ b/drivers/staging/media/tegra/TODO
> @@ -0,0 +1,10 @@
> +TODO list
> +* Currently driver supports Tegra build-in TPG Only with direct media links from CSI to VI.
> +  Update the driver to do TPG Vs Sensor media links based on the kernel config CONFIG_VIDEO_TEGRA_TPG.
> +* Add real camera sensor capture support
> +* Add RAW10 packed video format support to Tegra210 video formats
> +* Add Tegra CSI MIPI pads calibration
> +* Add MIPI clock Settle time computation based on the data rate
> +* Add support for Ganged mode
> +* Make sure v4l2-compliance tests pass with all of the above implementations.
> +* Add SMMU support for VI to avoid cma_alloc failures with higher resolutions of some video formats.
> diff --git a/drivers/staging/media/tegra/csi.h b/drivers/staging/media/tegra/csi.h
> new file mode 100644
> index 000000000000..81cdda4b6bdd
> --- /dev/null
> +++ b/drivers/staging/media/tegra/csi.h
> @@ -0,0 +1,111 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#ifndef __CSI_H_
> +#define __CSI_H_
> +
> +#include <media/media-device.h>
> +#include <media/media-entity.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-dev.h>
> +#include <media/videobuf2-v4l2.h>
> +
> +/*
> + * Each CSI brick supports max of 4 lanes that can be used as either
> + * one x4 port using both CILA and CILB partitions of a CSI brick or can
> + * be used as two x2 ports with one x2 from CILA and the other x2 from
> + * CILB.
> + */
> +#define CSI_LANES_PER_BRICK	4
> +#define CSI_PORTS_PER_BRICK	2
> +
> +/* each CSI channel can have one sink and one source pads */
> +#define TEGRA_CSI_PADS_NUM	2
> +
> +enum tegra_csi_cil_port {
> +	PORT_A = 0,
> +	PORT_B,
> +};
> +
> +enum tegra_csi_block {
> +	CSI_CIL_AB = 0,
> +	CSI_CIL_CD,
> +	CSI_CIL_EF,
> +};
> +
> +struct tegra_csi_device;
> +
> +struct tegra_csi_port {
> +	void __iomem *pixel_parser;
> +	void __iomem *cila;
> +	void __iomem *cilb;
> +	void __iomem *tpg;
> +
> +	/* one pair of sink/source pad has one format */
> +	struct v4l2_mbus_framefmt format;
> +	unsigned int lanes;
> +};
> +
> +struct tegra_csi_channel {
> +	struct list_head list;
> +	struct v4l2_subdev subdev;
> +	struct media_pad pads[TEGRA_CSI_PADS_NUM];
> +	struct device_node *of_node;
> +	struct tegra_csi_device *csi;
> +	struct tegra_csi_port *ports;
> +	unsigned int numlanes;
> +	unsigned int numpads;
> +	u8 csi_port_num;
> +
> +	/* protects csi channel ports format fields */
> +	struct mutex format_lock;
> +};
> +
> +struct tegra_csi_soc_data {
> +	const struct tegra_csi_fops *csi_fops;
> +	unsigned int cil_max_clk_hz;
> +	unsigned int num_tpg_channels;
> +};
> +
> +/**
> + * struct tegra_csi_device - NVIDIA Tegra CSI device structure
> + * @dev: device struct
> + * @client: host1x_client struct
> + *
> + * @iomem: register base
> + * @csi_clk: clock for CSI
> + * @cilab_clk: clock for CIL AB
> + * @cilcd_clk: clock for CIL CD
> + * @cilef_clk: clock for CIL EF
> + * @tpg_clk: clock for internal CSI TPG logic
> + *
> + * @soc_data: pointer to SoC data structure
> + * @fops: csi operations
> + *
> + * @channels: list of CSI channels
> + */
> +struct tegra_csi_device {
> +	struct device *dev;
> +	struct host1x_client client;
> +
> +	void __iomem *iomem;
> +	struct clk *csi_clk;
> +	struct clk *cilab_clk;
> +	struct clk *cilcd_clk;
> +	struct clk *cilef_clk;
> +	struct clk *tpg_clk;
> +	atomic_t clk_refcnt;
> +
> +	const struct tegra_csi_soc_data *soc_data;
> +	const struct tegra_csi_fops *fops;
> +
> +	struct list_head csi_chans;
> +};
> +
> +void tegra_csi_error_status(struct v4l2_subdev *subdev);
> +
> +#endif
> diff --git a/drivers/staging/media/tegra/csi2_fops.c b/drivers/staging/media/tegra/csi2_fops.c
> new file mode 100644
> index 000000000000..5f2f7bd3ae50
> --- /dev/null
> +++ b/drivers/staging/media/tegra/csi2_fops.c
> @@ -0,0 +1,335 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/clk/tegra.h>
> +#include <linux/delay.h>
> +
> +#include "vi2_registers.h"
> +#include "mc_common.h"
> +#include "csi2_fops.h"
> +#include "csi.h"
> +
> +/* CSI block registers offset */
> +#define TEGRA210_CSI_PORT_OFFSET		0x34
> +/* CSI CIL parition registers offset */
> +#define TEGRA210_CSI_CIL_OFFSET			0x0f4
> +/* CSI TPG registers offset */
> +#define TEGRA210_CSI_TPG_OFFSET			0x18c
> +
> +#define CSI_PP_OFFSET(block)	((block) * 0x800)
> +
> +static void csi_write(struct tegra_csi_channel *chan, u8 block,
> +		      unsigned int addr, u32 val)
> +{
> +	void __iomem *csi_pp_base;
> +
> +	csi_pp_base = chan->csi->iomem + CSI_PP_OFFSET(block);
> +	writel(val, csi_pp_base + addr);
> +}
> +
> +/* Pixel parser registers accessors */
> +static void pp_write(struct tegra_csi_port *port, u32 addr, u32 val)
> +{
> +	writel(val, port->pixel_parser + addr);
> +}
> +
> +static u32 pp_read(struct tegra_csi_port *port, u32 addr)
> +{
> +	return readl(port->pixel_parser + addr);
> +}
> +
> +/* CSI CIL A/B port registers accessors */
> +static void cil_write(struct tegra_csi_port *port, u8 port_id,
> +		      u32 addr, u32 val)
> +{
> +	if (port_id & PORT_B)
> +		writel(val, port->cilb + addr);
> +	else
> +		writel(val, port->cila + addr);
> +}
> +
> +static u32 cil_read(struct tegra_csi_port *port, u8 port_id,
> +		    u32 addr)
> +{
> +	if (port_id & PORT_B)
> +		return readl(port->cilb + addr);
> +	else
> +		return readl(port->cila + addr);
> +}
> +
> +/* Test pattern generator registers accessor */
> +static void tpg_write(struct tegra_csi_port *port, unsigned int addr, u32 val)
> +{
> +	writel(val, port->tpg + addr);
> +}
> +
> +static void csi2_error_status(struct tegra_csi_channel *csi_chan)
> +{
> +	struct tegra_csi_device *csi = csi_chan->csi;
> +	unsigned int port_num = csi_chan->csi_port_num;
> +	struct tegra_csi_port *port = csi_chan->ports;
> +	u32 val;
> +
> +	val = pp_read(port, TEGRA_CSI_PIXEL_PARSER_STATUS);
> +	dev_err(csi->dev, "TEGRA_CSI_PIXEL_PARSER_STATUS 0x%08x\n", val);
> +
> +	val = cil_read(port, port_num, TEGRA_CSI_CIL_STATUS);
> +	dev_err(csi->dev, "TEGRA_CSI_CIL_STATUS 0x%08x\n", val);
> +
> +	val = cil_read(port, port_num, TEGRA_CSI_CILX_STATUS);
> +	dev_err(csi->dev, "TEGRA_CSI_CILX_STATUS 0x%08x\n", val);
> +}
> +
> +static int csi2_start_streaming(struct tegra_csi_channel *csi_chan,
> +				u8 pg_mode, int enable)
> +{
> +	struct tegra_csi_device *csi = csi_chan->csi;
> +	unsigned int port_num = csi_chan->csi_port_num;
> +	unsigned int block = port_num >> 1;
> +	struct tegra_csi_port *port = csi_chan->ports;
> +	unsigned int cil_max_freq = csi->soc_data->cil_max_clk_hz;
> +	struct clk *cil_clk;
> +	int ret;
> +
> +	if (block == CSI_CIL_AB)
> +		cil_clk = csi->cilab_clk;
> +	else if (block == CSI_CIL_CD)
> +		cil_clk = csi->cilcd_clk;
> +	else
> +		cil_clk = csi->cilef_clk;
> +
> +	if (enable) {
> +		ret = clk_set_rate(cil_clk, cil_max_freq);
> +		if (ret)
> +			dev_err(csi->dev,
> +				"failed to set cil clk rate, err: %d\n", ret);
> +
> +		/* enable CIL clock on first open */
> +		if (atomic_add_return(1, &csi->clk_refcnt) == 1) {
> +			ret = clk_prepare_enable(cil_clk);
> +			if (ret) {
> +				dev_err(csi->dev,
> +					"failed to enable cil clk, err: %d\n",
> +					ret);
> +				return ret;
> +			}
> +		}
> +
> +		/*
> +		 * On Tegra210, TPG internal logic uses PLLD out along with
> +		 * the CIL clock.
> +		 * So, enable TPG clock during TPG mode streaming.
> +		 */
> +		if (pg_mode) {
> +			ret = clk_set_rate(csi->tpg_clk, TEGRA210_TPG_CLOCK);
> +			if (ret)
> +				dev_err(csi->dev,
> +					"failed to set tpg clk rate\n");
> +
> +			ret = clk_prepare_enable(csi->tpg_clk);
> +			if (ret) {
> +				dev_err(csi->dev,
> +					"failed to enable tpg clk, err: %d\n",
> +					ret);
> +				return ret;
> +			}
> +		}
> +
> +		csi_write(csi_chan, block, TEGRA_CSI_CLKEN_OVERRIDE, 0);
> +
> +		/* clean up status */
> +		pp_write(port, TEGRA_CSI_PIXEL_PARSER_STATUS, 0xFFFFFFFF);
> +		cil_write(port, port_num, TEGRA_CSI_CIL_STATUS, 0xFFFFFFFF);
> +		cil_write(port, port_num, TEGRA_CSI_CILX_STATUS, 0xFFFFFFFF);
> +		cil_write(port, port_num, TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0);
> +
> +		/* CIL PHY registers setup */
> +		cil_write(port, port_num, TEGRA_CSI_CIL_PAD_CONFIG0, 0x0);
> +		cil_write(port, port_num, TEGRA_CSI_CIL_PHY_CONTROL, 0xA);
> +
> +		/*
> +		 * The CSI unit provides for connection of up to six cameras in
> +		 * the system and is organized as three identical instances of
> +		 * two MIPI support blocks, each with a separate 4-lane
> +		 * interface that can be configured as a single camera with 4
> +		 * lanes or as a dual camera with 2 lanes available for each
> +		 * camera.
> +		 */
> +		if (port->lanes == 4) {
> +			cil_write(port, port_num, TEGRA_CSI_CIL_PAD_CONFIG0,
> +				  BRICK_CLOCK_A_4X);
> +
> +			cil_write(port, (port_num + 1),
> +				  TEGRA_CSI_CIL_PAD_CONFIG0, 0x0);
> +
> +			cil_write(port, (port_num + 1),
> +				  TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0);
> +
> +			cil_write(port, (port_num + 1),
> +				  TEGRA_CSI_CIL_PHY_CONTROL, 0xA);
> +
> +			csi_write(csi_chan, block, TEGRA_CSI_PHY_CIL_COMMAND,
> +				  CSI_A_PHY_CIL_ENABLE | CSI_B_PHY_CIL_ENABLE);
> +		} else {
> +			u32 val = ((port_num & 1) == PORT_A) ?
> +				  CSI_A_PHY_CIL_ENABLE | CSI_B_PHY_CIL_NOP :
> +				  CSI_B_PHY_CIL_ENABLE | CSI_A_PHY_CIL_NOP;
> +			csi_write(csi_chan, block, TEGRA_CSI_PHY_CIL_COMMAND,
> +				  val);
> +		}
> +
> +		/* CSI pixel parser registers setup */
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
> +			 (0xF << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
> +			 CSI_PP_SINGLE_SHOT_ENABLE | CSI_PP_RST);
> +		pp_write(port, TEGRA_CSI_PIXEL_PARSER_INTERRUPT_MASK, 0x0);
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_CONTROL0,
> +			 CSI_PP_PACKET_HEADER_SENT |
> +			 CSI_PP_DATA_IDENTIFIER_ENABLE |
> +			 CSI_PP_WORD_COUNT_SELECT_HEADER |
> +			 CSI_PP_CRC_CHECK_ENABLE |  CSI_PP_WC_CHECK |
> +			 CSI_PP_OUTPUT_FORMAT_STORE |
> +			 CSI_PP_HEADER_EC_DISABLE | CSI_PPA_PAD_FRAME_NOPAD |
> +			 (port_num & 1));
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_CONTROL1,
> +			 (0x1 << CSI_PP_TOP_FIELD_FRAME_OFFSET) |
> +			 (0x1 << CSI_PP_TOP_FIELD_FRAME_MASK_OFFSET));
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_GAP,
> +			 0x14 << PP_FRAME_MIN_GAP_OFFSET);
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_EXPECTED_FRAME, 0x0);
> +		pp_write(port, TEGRA_CSI_INPUT_STREAM_CONTROL,
> +			 (0x3f << CSI_SKIP_PACKET_THRESHOLD_OFFSET) |
> +			 (port->lanes - 1));
> +
> +		/* TPG setup */
> +		if (pg_mode) {
> +			tpg_write(port, TEGRA_CSI_PATTERN_GENERATOR_CTRL,
> +				  ((pg_mode - 1) << PG_MODE_OFFSET) |
> +				  PG_ENABLE);
> +			tpg_write(port, TEGRA_CSI_PG_PHASE, 0x0);
> +			tpg_write(port, TEGRA_CSI_PG_RED_FREQ,
> +				  (0x10 << PG_RED_VERT_INIT_FREQ_OFFSET) |
> +				  (0x10 << PG_RED_HOR_INIT_FREQ_OFFSET));
> +			tpg_write(port, TEGRA_CSI_PG_RED_FREQ_RATE, 0x0);
> +			tpg_write(port, TEGRA_CSI_PG_GREEN_FREQ,
> +				  (0x10 << PG_GREEN_VERT_INIT_FREQ_OFFSET) |
> +				  (0x10 << PG_GREEN_HOR_INIT_FREQ_OFFSET));
> +			tpg_write(port, TEGRA_CSI_PG_GREEN_FREQ_RATE, 0x0);
> +			tpg_write(port, TEGRA_CSI_PG_BLUE_FREQ,
> +				  (0x10 << PG_BLUE_VERT_INIT_FREQ_OFFSET) |
> +				  (0x10 << PG_BLUE_HOR_INIT_FREQ_OFFSET));
> +			tpg_write(port, TEGRA_CSI_PG_BLUE_FREQ_RATE, 0x0);
> +		}
> +
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
> +			 (0xF << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
> +			 CSI_PP_SINGLE_SHOT_ENABLE | CSI_PP_ENABLE);
> +	} else {
> +		u32 val = pp_read(port, TEGRA_CSI_PIXEL_PARSER_STATUS);
> +
> +		dev_dbg(csi->dev, "TEGRA_CSI_PIXEL_PARSER_STATUS 0x%08x\n",
> +			val);
> +
> +		val = cil_read(port, port_num, TEGRA_CSI_CIL_STATUS);
> +		dev_dbg(csi->dev, "TEGRA_CSI_CIL_STATUS 0x%08x\n", val);
> +
> +		val = cil_read(port, port_num, TEGRA_CSI_CILX_STATUS);
> +		dev_dbg(csi->dev, "TEGRA_CSI_CILX_STATUS 0x%08x\n", val);
> +
> +		pp_write(port, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
> +			 (0xF << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
> +			 CSI_PP_DISABLE);
> +
> +		if (pg_mode) {
> +			tpg_write(port, TEGRA_CSI_PATTERN_GENERATOR_CTRL,
> +				  ((pg_mode - 1) << PG_MODE_OFFSET) |
> +				  PG_DISABLE);
> +			clk_disable_unprepare(csi->tpg_clk);
> +		}
> +
> +		if (port->lanes == 4) {
> +			csi_write(csi_chan, block, TEGRA_CSI_PHY_CIL_COMMAND,
> +				  CSI_A_PHY_CIL_DISABLE |
> +				  CSI_B_PHY_CIL_DISABLE);
> +
> +		} else {
> +			u32 val = ((port_num & 1) == PORT_A) ?
> +				  CSI_A_PHY_CIL_DISABLE | CSI_B_PHY_CIL_NOP :
> +				  CSI_B_PHY_CIL_DISABLE | CSI_A_PHY_CIL_NOP;
> +			csi_write(csi_chan, block, TEGRA_CSI_PHY_CIL_COMMAND,
> +				  val);
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int csi2_hw_init(struct tegra_csi_device *csi)
> +{
> +	struct tegra_csi_channel *csi_chan;
> +	struct tegra_csi_port *port;
> +	u8 portno;
> +	int ret;
> +
> +	csi->cilab_clk = devm_clk_get(csi->dev, "cilab");
> +	if (IS_ERR(csi->cilab_clk)) {
> +		dev_err(csi->dev, "Failed to get cilab clock\n");
> +		return PTR_ERR(csi->cilab_clk);
> +	}
> +
> +	csi->cilcd_clk = devm_clk_get(csi->dev, "cilcd");
> +	if (IS_ERR(csi->cilcd_clk)) {
> +		dev_err(csi->dev, "Failed to get cilcd clock\n");
> +		return PTR_ERR(csi->cilcd_clk);
> +	}
> +
> +	csi->cilef_clk = devm_clk_get(csi->dev, "cile");
> +	if (IS_ERR(csi->cilef_clk)) {
> +		dev_err(csi->dev, "Failed to get cile clock\n");
> +		return PTR_ERR(csi->cilef_clk);
> +	}
> +
> +	csi->tpg_clk = devm_clk_get(csi->dev, "csi_tpg");
> +	if (IS_ERR(csi->tpg_clk)) {
> +		dev_err(csi->dev, "Failed to get csi_tpg clock\n");
> +		return PTR_ERR(csi->tpg_clk);
> +	}
> +
> +	csi->csi_clk = devm_clk_get(csi->dev, "csi");
> +	if (IS_ERR(csi->csi_clk)) {
> +		dev_err(csi->dev, "Failed to get csi clock\n");
> +		return PTR_ERR(csi->csi_clk);
> +	}
> +
> +	ret = clk_prepare_enable(csi->csi_clk);
> +	if (ret) {
> +		dev_err(csi->dev, "Failed to enable csi clk, err: %d\n", ret);
> +		return ret;
> +	}
> +
> +	list_for_each_entry(csi_chan, &csi->csi_chans, list) {
> +		void __iomem *csi_pp_base;
> +
> +		port = csi_chan->ports;
> +		portno = csi_chan->csi_port_num;
> +		csi_pp_base = csi->iomem + CSI_PP_OFFSET(portno >> 1);
> +		port->pixel_parser = csi_pp_base +
> +				     (portno % CSI_PORTS_PER_BRICK) *
> +				     TEGRA210_CSI_PORT_OFFSET;
> +		port->cila = csi_pp_base + TEGRA210_CSI_CIL_OFFSET;
> +		port->cilb = port->cila + TEGRA210_CSI_PORT_OFFSET;
> +		port->tpg = port->pixel_parser + TEGRA210_CSI_TPG_OFFSET;
> +	}
> +
> +	return 0;
> +}
> +
> +const struct tegra_csi_fops csi2_fops = {
> +	.hw_init = csi2_hw_init,
> +	.csi_start_streaming = csi2_start_streaming,
> +	.csi_err_status = csi2_error_status,
> +};
> +EXPORT_SYMBOL(csi2_fops);
> diff --git a/drivers/staging/media/tegra/csi2_fops.h b/drivers/staging/media/tegra/csi2_fops.h
> new file mode 100644
> index 000000000000..cf22a28ceb1f
> --- /dev/null
> +++ b/drivers/staging/media/tegra/csi2_fops.h
> @@ -0,0 +1,15 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#ifndef __CSI2_H__
> +#define __CSI2_H__
> +
> +#define	TEGRA210_TPG_CLOCK		594000000
> +#define	TEGRA210_CSI_CIL_CLK_MAX	102000000
> +#define TEGRA210_CSI_BRICKS_MAX		3
> +
> +extern const struct tegra_csi_fops csi2_fops;
> +
> +#endif
> diff --git a/drivers/staging/media/tegra/host1x-video.c b/drivers/staging/media/tegra/host1x-video.c
> new file mode 100644
> index 000000000000..740806121e6b
> --- /dev/null
> +++ b/drivers/staging/media/tegra/host1x-video.c
> @@ -0,0 +1,120 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#include <linux/host1x.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#include "host1x-video.h"
> +
> +static int host1x_video_probe(struct host1x_device *dev)
> +{
> +	struct tegra_camera *cam;
> +	int ret;
> +
> +	cam = devm_kzalloc(&dev->dev, sizeof(*cam), GFP_KERNEL);
> +	if (!cam)
> +		return -ENOMEM;
> +
> +	cam->dev = get_device(&dev->dev);
> +	cam->media_dev.dev = cam->dev;
> +	strscpy(cam->media_dev.model, "NVIDIA Tegra Video Input Device",
> +		sizeof(cam->media_dev.model));
> +	cam->media_dev.hw_revision = 3;
> +
> +	media_device_init(&cam->media_dev);
> +	ret = media_device_register(&cam->media_dev);
> +	if (ret < 0) {
> +		dev_err(cam->dev, "failed to register media device: %d\n", ret);
> +		return ret;
> +	}
> +
> +	cam->v4l2_dev.mdev = &cam->media_dev;
> +	ret = v4l2_device_register(cam->dev, &cam->v4l2_dev);
> +	if (ret < 0) {
> +		dev_err(cam->dev, "V4L2 device registration failed: %d\n", ret);
> +		goto register_error;
> +	}
> +
> +	dev_set_drvdata(&dev->dev, cam);
> +
> +	ret = host1x_device_init(dev);
> +	if (ret < 0)
> +		goto dev_exit;
> +
> +	return 0;
> +
> +dev_exit:
> +	host1x_device_exit(dev);
> +	v4l2_device_unregister(&cam->v4l2_dev);
> +register_error:
> +	media_device_unregister(&cam->media_dev);
> +	media_device_cleanup(&cam->media_dev);
> +
> +	return ret;
> +}
> +
> +static int host1x_video_remove(struct host1x_device *dev)
> +{
> +	struct tegra_camera *cam = dev_get_drvdata(&dev->dev);
> +
> +	host1x_device_exit(dev);
> +	v4l2_device_unregister(&cam->v4l2_dev);
> +	media_device_unregister(&cam->media_dev);
> +	media_device_cleanup(&cam->media_dev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id host1x_video_subdevs[] = {
> +	{ .compatible = "nvidia,tegra210-csi", },
> +	{ .compatible = "nvidia,tegra210-vi", },
> +	{ }
> +};
> +
> +static struct host1x_driver host1x_video_driver = {
> +	.driver = {
> +		.name = "host1x_video",
> +	},
> +	.probe = host1x_video_probe,
> +	.remove = host1x_video_remove,
> +	.subdevs = host1x_video_subdevs,
> +};
> +
> +static struct platform_driver * const drivers[] = {
> +	&tegra_csi_driver,
> +	&tegra_vi_driver,
> +};
> +
> +static int __init host1x_video_init(void)
> +{
> +	int err;
> +
> +	err = host1x_driver_register(&host1x_video_driver);
> +	if (err < 0)
> +		return err;
> +
> +	err = platform_register_drivers(drivers, ARRAY_SIZE(drivers));
> +	if (err < 0)
> +		goto unregister_host1x;
> +
> +	return 0;
> +
> +unregister_host1x:
> +	host1x_driver_unregister(&host1x_video_driver);
> +	return err;
> +}
> +module_init(host1x_video_init);
> +
> +static void __exit host1x_video_exit(void)
> +{
> +	platform_unregister_drivers(drivers, ARRAY_SIZE(drivers));
> +	host1x_driver_unregister(&host1x_video_driver);
> +}
> +module_exit(host1x_video_exit);
> +
> +MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@nvidia.com>");
> +MODULE_DESCRIPTION("NVIDIA Tegra Host1x Video driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/staging/media/tegra/host1x-video.h b/drivers/staging/media/tegra/host1x-video.h
> new file mode 100644
> index 000000000000..84d28e6f4362
> --- /dev/null
> +++ b/drivers/staging/media/tegra/host1x-video.h
> @@ -0,0 +1,33 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#ifndef HOST1X_VIDEO_H
> +#define HOST1X_VIDEO_H 1
> +
> +#include <linux/host1x.h>
> +
> +#include <media/media-device.h>
> +#include <media/media-entity.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-dev.h>
> +#include <media/videobuf2-v4l2.h>
> +
> +#include "tegra-vi.h"
> +#include "csi.h"
> +
> +struct tegra_camera {
> +	struct v4l2_device v4l2_dev;
> +	struct media_device media_dev;
> +	struct device *dev;
> +	struct tegra_vi *vi;
> +	struct tegra_csi_device *csi;
> +};
> +
> +extern struct platform_driver tegra_vi_driver;
> +extern struct platform_driver tegra_csi_driver;
> +
> +#endif /* HOST1X_VIDEO_H */
> diff --git a/drivers/staging/media/tegra/mc_common.h b/drivers/staging/media/tegra/mc_common.h
> new file mode 100644
> index 000000000000..9e88f3295ef4
> --- /dev/null
> +++ b/drivers/staging/media/tegra/mc_common.h
> @@ -0,0 +1,131 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#ifndef __MC_COMMON_H_
> +#define __MC_COMMON_H_
> +
> +#include <linux/host1x.h>
> +#include <linux/mutex.h>
> +#include <linux/spinlock.h>
> +
> +#include <media/media-device.h>
> +#include <media/media-entity.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-dev.h>
> +#include <media/videobuf2-v4l2.h>
> +
> +#include "tegra-core.h"
> +#include "tegra-vi.h"
> +#include "csi.h"
> +
> +#define MAX_FORMAT_NUM	64
> +
> +struct tegra_csi_fops {
> +	int (*hw_init)(struct tegra_csi_device *csi);
> +	int (*csi_start_streaming)(struct tegra_csi_channel *csi_chan,
> +				   u8 pg_mode, int enable);
> +	void (*csi_err_status)(struct tegra_csi_channel *csi_chan);
> +};
> +
> +/**
> + * struct tegra_channel - Tegra video channel
> + * @list: list entry in a composite device dmas list
> + * @video: V4L2 video device associated with the video channel
> + * @video_lock: protects the @format and @queue fields
> + * @pad: media pad for the video device entity
> + *
> + * @vi: composite device DT node port number for the channel
> + *
> + * @sp: host1x syncpoint pointer
> + *
> + * @kthread_capture_start: capture start kthread of this video channel
> + * @start_wait: wait queue used by capture start kthread
> + * @kthread_capture_done: capture done kthread of this video channel
> + * @done_wait: wait queue used by capture done kthread
> + *
> + * @format: active V4L2 pixel format
> + * @fmtinfo: format information corresponding to the active @format
> + * @video_formats: supported video formats
> + * @nformats: supported number of video formats
> + *
> + * @queue: vb2 buffers queue
> + * @sequence: V4L2 buffers sequence number
> + *
> + * @capture: list of queued buffers for capture
> + * @start_lock: protects the capture queued list
> + * @done: list of capture done queued buffers
> + * @done_lock: protects the capture done queue list
> + *
> + * @stride_align: channel buffer stride alignment
> + * @width_align: channel buffer width alignment
> + * @height_align: channel buffer height alignment
> + * @size_align: channel buffer size alignment
> +
> + * @port: CSI port of this video channel
> + *
> + * @ctrl_handler: V4L2 control handler of this video channel
> + * @tpg_fmts_bitmap: a bitmap for supported TPG formats
> + */
> +struct tegra_channel {
> +	struct list_head list;
> +	struct video_device video;
> +	/* protects the @format and @queue fields */
> +	struct mutex video_lock;
> +	struct media_pad pad;
> +
> +	struct tegra_vi *vi;
> +	struct host1x_syncpt *sp;
> +
> +	struct task_struct *kthread_capture_start;
> +	wait_queue_head_t start_wait;
> +	struct task_struct *kthread_capture_done;
> +	wait_queue_head_t done_wait;
> +
> +	struct v4l2_pix_format format;
> +	const struct tegra_video_format *fmtinfo;
> +	const struct tegra_video_format *video_formats;
> +	unsigned int nformats;
> +	struct vb2_queue queue;
> +	u32 sequence;
> +
> +	struct list_head capture;
> +	/* protects the capture queued list */
> +	spinlock_t start_lock;
> +	struct list_head done;
> +	/* protects the capture done queue list */
> +	spinlock_t done_lock;
> +
> +	unsigned int stride_align;
> +	unsigned int width_align;
> +	unsigned int height_align;
> +	unsigned int size_align;
> +	unsigned char port;
> +
> +	struct v4l2_ctrl_handler ctrl_handler;
> +	DECLARE_BITMAP(tpg_fmts_bitmap, MAX_FORMAT_NUM);
> +};
> +
> +#define to_tegra_channel(vdev) \
> +	container_of(vdev, struct tegra_channel, video)
> +
> +const struct tegra_video_format *tegra_core_get_default_format(void);
> +u32 tegra_core_get_fourcc_by_idx(struct tegra_channel *chan,
> +				 unsigned int index);
> +int tegra_core_get_idx_by_code(struct tegra_channel *chan, unsigned int code,
> +			       unsigned int offset);
> +const struct tegra_video_format *
> +tegra_core_get_format_by_fourcc(struct tegra_channel *chan, u32 fourcc);
> +
> +int tegra_channel_init(struct tegra_channel *chan);
> +int tegra_channel_setup_ctrl_handler(struct tegra_channel *chan);
> +int tegra_channel_cleanup(struct tegra_channel *chan);
> +int tegra_channel_set_stream(struct tegra_channel *chan, bool on);
> +void tegra_channel_queued_buf_done(struct tegra_channel *chan,
> +				   enum vb2_buffer_state state);
> +int tegra_channel_csi_error_status(struct tegra_channel *chan);
> +
> +#endif
> diff --git a/drivers/staging/media/tegra/tegra-channel.c b/drivers/staging/media/tegra/tegra-channel.c
> new file mode 100644
> index 000000000000..7561f6fb8748
> --- /dev/null
> +++ b/drivers/staging/media/tegra/tegra-channel.c
> @@ -0,0 +1,628 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#include <linux/atomic.h>
> +#include <linux/bitmap.h>
> +#include <linux/clk.h>
> +#include <linux/host1x.h>
> +#include <linux/kthread.h>
> +#include <linux/lcm.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-fh.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include <soc/tegra/pmc.h>
> +
> +#include "mc_common.h"
> +#include "tegra-vi.h"
> +#include "host1x-video.h"
> +
> +#define MAX_CID_CONTROLS		1
> +
> +static const char *const vi_pattern_strings[] = {
> +	"Black/White Direct Mode",
> +	"Color Patch Mode",
> +};
> +
> +static int vi_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct tegra_channel *chan = container_of(ctrl->handler,
> +						  struct tegra_channel,
> +						  ctrl_handler);
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_TEST_PATTERN:
> +		chan->vi->pg_mode = ctrl->val + 1;
> +		dev_info(chan->vi->dev, "TPG mode is set to %s\n",
> +			 vi_pattern_strings[ctrl->val]);

There is no need to spam the log with this message.

> +		break;
> +
> +	default:
> +		dev_err(chan->vi->dev, "Invalid Tegra video control\n");

This can be dropped as well. Actually, this should never happen since the
control framework will call this function for valid controls only.

> +		return -EINVAL;

Traditionally the 'default: return -EINVAL;' is kept, just in case we ever
hit this through some regression.

> +	}
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ctrl_ops vi_ctrl_ops = {
> +	.s_ctrl	= vi_s_ctrl,
> +};
> +
> +/*
> + * videobuf2 queue operations
> + */
> +static int tegra_channel_queue_setup(struct vb2_queue *vq,
> +				     unsigned int *nbuffers,
> +				     unsigned int *nplanes,
> +				     unsigned int sizes[],
> +				     struct device *alloc_devs[])
> +{
> +	struct tegra_channel *chan = vb2_get_drv_priv(vq);
> +	unsigned int count = *nbuffers;
> +
> +	if (*nplanes)
> +		return sizes[0] < chan->format.sizeimage ? -EINVAL : 0;
> +
> +	*nplanes = 1;
> +	sizes[0] = chan->format.sizeimage;
> +	alloc_devs[0] = chan->vi->dev;
> +
> +	return 0;
> +}
> +
> +static int tegra_channel_buffer_prepare(struct vb2_buffer *vb)
> +{
> +	struct tegra_channel *chan = vb2_get_drv_priv(vb->vb2_queue);
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct tegra_channel_buffer *buf = to_tegra_channel_buffer(vbuf);
> +	unsigned long size = chan->format.sizeimage;
> +
> +	if (vb2_plane_size(vb, 0) < size) {
> +		v4l2_err(chan->video.v4l2_dev, "buffer too small (%lu < %lu)\n",
> +			 vb2_plane_size(vb, 0), size);
> +		return -EINVAL;
> +	}
> +
> +	vb2_set_plane_payload(vb, 0, size);
> +	buf->chan = chan;
> +	buf->addr = vb2_dma_contig_plane_dma_addr(vb, 0);
> +
> +	return 0;
> +}
> +
> +static void tegra_channel_buffer_queue(struct vb2_buffer *vb)
> +{
> +	struct tegra_channel *chan = vb2_get_drv_priv(vb->vb2_queue);
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct tegra_channel_buffer *buf = to_tegra_channel_buffer(vbuf);
> +
> +	/* put buffer into the capture queue */
> +	spin_lock(&chan->start_lock);
> +	list_add_tail(&buf->queue, &chan->capture);
> +	spin_unlock(&chan->start_lock);
> +
> +	/* wait up kthread for capture */
> +	wake_up_interruptible(&chan->start_wait);
> +}
> +
> +int tegra_channel_csi_error_status(struct tegra_channel *chan)
> +{
> +	struct media_entity *entity;
> +	struct media_pad *pad;
> +	struct v4l2_subdev *subdev;
> +
> +	pad = media_entity_remote_pad(&chan->pad);
> +	if (!pad)
> +		return -ENODEV;
> +
> +	entity = pad->entity;
> +	subdev = media_entity_to_v4l2_subdev(entity);
> +
> +	tegra_csi_error_status(subdev);
> +
> +	return 0;
> +}
> +
> +static struct v4l2_subdev *
> +tegra_channel_get_remote_subdev(struct tegra_channel *chan)
> +{
> +	struct media_pad *pad;
> +	struct v4l2_subdev *subdev;
> +	struct media_entity *entity;
> +
> +	pad = media_entity_remote_pad(&chan->pad);
> +	entity = pad->entity;
> +	subdev = media_entity_to_v4l2_subdev(entity);
> +
> +	return subdev;
> +}
> +
> +int tegra_channel_set_stream(struct tegra_channel *chan, bool on)
> +{
> +	struct v4l2_subdev *subdev;
> +	int ret;
> +
> +	/* stream CSI */
> +	subdev = tegra_channel_get_remote_subdev(chan);
> +	v4l2_set_subdev_hostdata(subdev, chan);
> +	ret = v4l2_subdev_call(subdev, video, s_stream, on);
> +	if (on && ret < 0 && ret != -ENOIOCTLCMD)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +void tegra_channel_queued_buf_done(struct tegra_channel *chan,
> +				   enum vb2_buffer_state state)
> +{
> +	struct tegra_channel_buffer *buf, *nbuf;
> +
> +	spin_lock(&chan->start_lock);
> +	list_for_each_entry_safe(buf, nbuf, &chan->capture, queue) {
> +		vb2_buffer_done(&buf->buf.vb2_buf, state);
> +		list_del(&buf->queue);
> +	}
> +
> +	spin_unlock(&chan->start_lock);
> +}
> +
> +static int tegra_channel_start_streaming(struct vb2_queue *vq, u32 count)
> +{
> +	struct tegra_channel *chan = vb2_get_drv_priv(vq);
> +
> +	if (chan->vi->fops->vi_start_streaming)
> +		return chan->vi->fops->vi_start_streaming(vq, count);
> +
> +	return 0;
> +}
> +
> +static void tegra_channel_stop_streaming(struct vb2_queue *vq)
> +{
> +	struct tegra_channel *chan = vb2_get_drv_priv(vq);
> +
> +	if (chan->vi->fops->vi_start_streaming)
> +		chan->vi->fops->vi_stop_streaming(vq);
> +}
> +
> +static const struct vb2_ops tegra_channel_queue_qops = {
> +	.queue_setup = tegra_channel_queue_setup,
> +	.buf_prepare = tegra_channel_buffer_prepare,
> +	.buf_queue = tegra_channel_buffer_queue,
> +	.wait_prepare = vb2_ops_wait_prepare,
> +	.wait_finish = vb2_ops_wait_finish,
> +	.start_streaming = tegra_channel_start_streaming,
> +	.stop_streaming = tegra_channel_stop_streaming,
> +};
> +
> +/*
> + * V4L2 ioctls
> + */
> +static int tegra_channel_querycap(struct file *file, void *fh,
> +				  struct v4l2_capability *cap)
> +{
> +	struct v4l2_fh *vfh = file->private_data;
> +	struct tegra_channel *chan = to_tegra_channel(vfh->vdev);
> +
> +	cap->device_caps = chan->video.device_caps;
> +	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;

Just drop these two lines. You already set device_caps in struct video_device,
and that's sufficient. The v4l2 core will set these two fields for you
based on the video_device.

> +	strscpy(cap->driver, "tegra-video", sizeof(cap->driver));
> +	strscpy(cap->card, chan->video.name, sizeof(cap->card));
> +	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s:%u",
> +		 dev_name(chan->vi->dev), chan->port);
> +
> +	return 0;
> +}
> +
> +static int tegra_channel_enum_format(struct file *file, void *fh,
> +				     struct v4l2_fmtdesc *f)
> +{
> +	struct v4l2_fh *vfh = file->private_data;
> +	struct tegra_channel *chan = to_tegra_channel(vfh->vdev);
> +	unsigned int index = 0, i;
> +	unsigned long *fmts_bitmap = chan->tpg_fmts_bitmap;
> +
> +	if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
> +		return -EINVAL;
> +
> +	for (i = 0; i < f->index + 1; i++, index++)
> +		index = find_next_bit(fmts_bitmap, MAX_FORMAT_NUM, index);
> +
> +	f->pixelformat = tegra_core_get_fourcc_by_idx(chan, index - 1);
> +
> +	return 0;
> +}
> +
> +static void
> +tegra_channel_fmt_align(struct tegra_channel *chan,
> +			const struct tegra_frac *bpp,
> +			u32 *width, u32 *height, u32 *bytesperline)
> +{
> +	unsigned int min_width, max_width;
> +	unsigned int min_bpl, max_bpl, bpl;
> +	unsigned int align, fmt_align;
> +	unsigned int temp_width, temp_bpl;
> +	unsigned int numerator, denominator;
> +
> +	denominator = (!bpp->denominator) ? 1 : bpp->denominator;
> +	numerator = (!bpp->numerator) ? 1 : bpp->numerator;
> +	fmt_align = (denominator == 1) ? numerator : 1;
> +	align = lcm(chan->width_align, fmt_align);
> +	bpl = (*width * numerator) / denominator;
> +
> +	if (chan->vi->fops->vi_stride_align)
> +		chan->vi->fops->vi_stride_align(&bpl);
> +
> +	if (!*bytesperline)
> +		*bytesperline = bpl;
> +
> +	/*
> +	 * The transfer alignment requirements are expressed in bytes. Compute
> +	 * the minimum and maximum values, clamp the requested width and convert
> +	 * it back to pixels.
> +	 * use bytesperline to adjust width for applicaton related requriements.
> +	 */
> +	min_width = roundup(TEGRA_MIN_WIDTH, align);
> +	max_width = rounddown(TEGRA_MAX_WIDTH, align);
> +	temp_width = roundup(bpl, align);
> +	*width = (clamp(temp_width, min_width, max_width) * denominator) /
> +			numerator;
> +	*height = clamp(*height, TEGRA_MIN_HEIGHT, TEGRA_MAX_HEIGHT);
> +
> +	/*
> +	 * Clamp the requested bytes per line value. If the maximum bytes per
> +	 * line value is zero, the module doesn't support user configurable line
> +	 * sizes. Override the requested value with the minimum in that case.
> +	 */
> +	min_bpl = bpl;
> +	max_bpl = rounddown(TEGRA_MAX_WIDTH, chan->stride_align);
> +	temp_bpl = roundup(*bytesperline, chan->stride_align);
> +	*bytesperline = clamp(temp_bpl, min_bpl, max_bpl);
> +}
> +
> +static void tegra_channel_update_format(struct tegra_channel *chan, u32 width,
> +					u32 height, u32 fourcc,
> +					const struct tegra_frac *bpp,
> +					u32 preferred_stride)
> +{
> +	u32 denominator = (!bpp->denominator) ? 1 : bpp->denominator;
> +	u32 numerator = (!bpp->numerator) ? 1 : bpp->numerator;
> +	u32 bytesperline = (width * numerator / denominator);
> +	u32 sizeimage, height_aligned;
> +
> +	chan->format.width = width;
> +	chan->format.height = height;
> +	chan->format.pixelformat = fourcc;
> +	chan->format.bytesperline = preferred_stride ?: bytesperline;
> +
> +	tegra_channel_fmt_align(chan, bpp,
> +				&chan->format.width,
> +				&chan->format.height,
> +				&chan->format.bytesperline);
> +
> +	/* calculate the sizeimage per plane */
> +	height_aligned = roundup(chan->format.height, chan->height_align);
> +	sizeimage = chan->format.bytesperline * height_aligned;
> +	chan->format.sizeimage = roundup(sizeimage, chan->size_align);
> +}
> +
> +static int tegra_channel_get_format(struct file *file, void *fh,
> +				    struct v4l2_format *format)
> +{
> +	struct v4l2_fh *vfh = file->private_data;
> +	struct tegra_channel *chan = to_tegra_channel(vfh->vdev);
> +
> +	format->fmt.pix = chan->format;
> +
> +	return 0;
> +}
> +
> +static int __tegra_channel_try_format(struct tegra_channel *chan,
> +				      struct v4l2_pix_format *pix,
> +				      const struct tegra_video_format **vfmt)
> +{
> +	const struct tegra_video_format *fmt_info;
> +	struct v4l2_subdev *subdev;
> +	struct v4l2_subdev_format fmt;
> +	struct v4l2_subdev_pad_config *pad_cfg;
> +
> +	subdev = tegra_channel_get_remote_subdev(chan);
> +	pad_cfg = v4l2_subdev_alloc_pad_config(subdev);
> +	if (!pad_cfg)
> +		return -ENOMEM;
> +
> +	/*
> +	 * Retrieve format information and select the default format if the
> +	 * requested format isn't supported.
> +	 */
> +	fmt_info = tegra_core_get_format_by_fourcc(chan, pix->pixelformat);
> +	if (!fmt_info) {
> +		pix->pixelformat = chan->format.pixelformat;
> +		pix->colorspace = chan->format.colorspace;
> +		fmt_info = tegra_core_get_format_by_fourcc(chan,
> +							   pix->pixelformat);
> +	}
> +
> +	/* Change this when start adding interlace format support */
> +	pix->field = V4L2_FIELD_NONE;
> +	fmt.which = V4L2_SUBDEV_FORMAT_TRY;
> +	fmt.pad = 0;
> +	v4l2_fill_mbus_format(&fmt.format, pix, fmt_info->code);
> +	v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
> +
> +	v4l2_fill_pix_format(pix, &fmt.format);
> +	tegra_channel_fmt_align(chan, &fmt_info->bpp, &pix->width, &pix->height,
> +				&pix->bytesperline);
> +	pix->sizeimage = pix->bytesperline * pix->height;
> +
> +	if (vfmt)
> +		*vfmt = fmt_info;
> +
> +	v4l2_subdev_free_pad_config(pad_cfg);
> +
> +	return 0;
> +}
> +
> +static int tegra_channel_try_format(struct file *file, void *fh,
> +				    struct v4l2_format *format)
> +{
> +	struct v4l2_fh *vfh = file->private_data;
> +	struct tegra_channel *chan = to_tegra_channel(vfh->vdev);
> +
> +	return __tegra_channel_try_format(chan, &format->fmt.pix, NULL);
> +}
> +
> +static int tegra_channel_set_format(struct file *file, void *fh,
> +				    struct v4l2_format *format)
> +{
> +	struct v4l2_fh *vfh = file->private_data;
> +	struct tegra_channel *chan = to_tegra_channel(vfh->vdev);
> +	const struct tegra_video_format *info;
> +	int ret;
> +	struct v4l2_subdev_format fmt;
> +	struct v4l2_subdev *subdev;
> +	struct v4l2_pix_format *pix = &format->fmt.pix;
> +
> +	if (vb2_is_busy(&chan->queue))
> +		return -EBUSY;
> +
> +	/* get supported format by try_fmt */
> +	ret = __tegra_channel_try_format(chan, pix, &info);
> +	if (ret)
> +		return ret;
> +
> +	subdev = tegra_channel_get_remote_subdev(chan);
> +
> +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> +	fmt.pad = 0;
> +	v4l2_fill_mbus_format(&fmt.format, pix, info->code);
> +	v4l2_subdev_call(subdev, pad, set_fmt, NULL, &fmt);
> +
> +	v4l2_fill_pix_format(pix, &fmt.format);
> +	chan->format = *pix;
> +	chan->fmtinfo = info;
> +	tegra_channel_update_format(chan, pix->width,
> +				    pix->height, info->fourcc,
> +				    &info->bpp,
> +				    pix->bytesperline);
> +	*pix = chan->format;
> +
> +	return 0;
> +}
> +
> +static int tegra_channel_enum_input(struct file *file, void *fh,
> +				    struct v4l2_input *inp)
> +{
> +	/* Currently driver supports internal TPG only */
> +	if (inp->index != 0)
> +		return -EINVAL;
> +
> +	inp->type = V4L2_INPUT_TYPE_CAMERA;
> +	strscpy(inp->name, "Tegra TPG", sizeof(inp->name));
> +
> +	return 0;
> +}
> +
> +static int tegra_channel_g_input(struct file *file, void *priv,
> +				 unsigned int *i)
> +{
> +	*i = 0;
> +	return 0;
> +}
> +
> +static int tegra_channel_s_input(struct file *file, void *priv,
> +				 unsigned int input)
> +{
> +	if (input > 0)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
> +	.vidioc_querycap		= tegra_channel_querycap,
> +	.vidioc_enum_fmt_vid_cap	= tegra_channel_enum_format,
> +	.vidioc_g_fmt_vid_cap		= tegra_channel_get_format,
> +	.vidioc_s_fmt_vid_cap		= tegra_channel_set_format,
> +	.vidioc_try_fmt_vid_cap		= tegra_channel_try_format,
> +	.vidioc_enum_input		= tegra_channel_enum_input,
> +	.vidioc_g_input			= tegra_channel_g_input,
> +	.vidioc_s_input			= tegra_channel_s_input,
> +	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
> +	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
> +	.vidioc_querybuf		= vb2_ioctl_querybuf,
> +	.vidioc_qbuf			= vb2_ioctl_qbuf,
> +	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
> +	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
> +	.vidioc_expbuf			= vb2_ioctl_expbuf,
> +	.vidioc_streamon		= vb2_ioctl_streamon,
> +	.vidioc_streamoff		= vb2_ioctl_streamoff,
> +	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
> +	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
> +};
> +
> +/*
> + * V4L2 file operations
> + */
> +static const struct v4l2_file_operations tegra_channel_fops = {
> +	.owner		= THIS_MODULE,
> +	.unlocked_ioctl	= video_ioctl2,
> +	.open		= v4l2_fh_open,
> +	.release	= vb2_fop_release,
> +	.read		= vb2_fop_read,
> +	.poll		= vb2_fop_poll,
> +	.mmap		= vb2_fop_mmap,
> +};
> +
> +int tegra_channel_setup_ctrl_handler(struct tegra_channel *chan)
> +{
> +	int ret;
> +
> +	/* Add test pattern control handler to v4l2 device */
> +	v4l2_ctrl_new_std_menu_items(&chan->ctrl_handler, &vi_ctrl_ops,
> +				     V4L2_CID_TEST_PATTERN,
> +				     ARRAY_SIZE(vi_pattern_strings) - 1,
> +				     0, 0, vi_pattern_strings);
> +	if (chan->ctrl_handler.error) {
> +		dev_err(chan->vi->dev, "failed to add TPG ctrl handler\n");
> +		v4l2_ctrl_handler_free(&chan->ctrl_handler);
> +		return chan->ctrl_handler.error;
> +	}
> +
> +	/* setup the controls */
> +	ret = v4l2_ctrl_handler_setup(&chan->ctrl_handler);
> +	if (ret < 0) {
> +		dev_err(chan->vi->dev, "failed to setup v4l2 ctrl handler\n");
> +		goto free_hdl;
> +	}
> +
> +	return 0;
> +
> +free_hdl:
> +	v4l2_ctrl_handler_free(&chan->ctrl_handler);
> +	return ret;
> +}
> +
> +int tegra_channel_init(struct tegra_channel *chan)
> +{
> +	struct tegra_vi *vi = chan->vi;
> +	struct tegra_camera *cam = dev_get_drvdata(vi->client.host);
> +	int ret;
> +
> +	mutex_init(&chan->video_lock);
> +	INIT_LIST_HEAD(&chan->capture);
> +	INIT_LIST_HEAD(&chan->done);
> +	spin_lock_init(&chan->start_lock);
> +	spin_lock_init(&chan->done_lock);
> +	init_waitqueue_head(&chan->start_wait);
> +	init_waitqueue_head(&chan->done_wait);
> +
> +	/* Default alignments */
> +	chan->width_align = TEGRA_WIDTH_ALIGNMENT;
> +	chan->stride_align = TEGRA_STRIDE_ALIGNMENT;
> +	chan->height_align = TEGRA_HEIGHT_ALIGNMENT;
> +	chan->size_align = TEGRA_SIZE_ALIGNMENT;
> +
> +	/* initialize the video format */
> +	chan->fmtinfo = tegra_core_get_default_format();
> +	chan->format.colorspace = V4L2_COLORSPACE_SRGB;
> +	chan->format.field = V4L2_FIELD_NONE;
> +	tegra_channel_update_format(chan, TEGRA_DEF_WIDTH, TEGRA_DEF_HEIGHT,
> +				    chan->fmtinfo->fourcc,
> +				    &chan->fmtinfo->bpp, 0);
> +
> +	/* initialize the media entity */
> +	chan->pad.flags = MEDIA_PAD_FL_SINK;
> +	ret = media_entity_pads_init(&chan->video.entity, 1, &chan->pad);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = v4l2_ctrl_handler_init(&chan->ctrl_handler, MAX_CID_CONTROLS);
> +	if (chan->ctrl_handler.error) {
> +		dev_err(vi->dev,
> +			"V4L2 controls handler init failed: %d\n", ret);
> +		goto ctrl_init_error;
> +	}
> +
> +	/* initialize the video_device */
> +	chan->video.fops = &tegra_channel_fops;
> +	chan->video.v4l2_dev = &cam->v4l2_dev;
> +	chan->video.queue = &chan->queue;
> +	snprintf(chan->video.name, sizeof(chan->video.name), "%s-%s-%u",
> +		 dev_name(vi->dev), "output", chan->port);
> +	chan->video.vfl_type = VFL_TYPE_GRABBER;
> +	chan->video.vfl_dir = VFL_DIR_RX;
> +	chan->video.release = video_device_release_empty;
> +	chan->video.ioctl_ops = &tegra_channel_ioctl_ops;
> +	chan->video.ctrl_handler = &chan->ctrl_handler;
> +	chan->video.lock = &chan->video_lock;
> +	chan->video.device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
> +				  V4L2_CAP_READWRITE;
> +
> +	video_set_drvdata(&chan->video, chan);
> +	chan->sp = host1x_syncpt_request(&vi->client, HOST1X_SYNCPT_HAS_BASE);
> +	if (!chan->sp) {
> +		dev_err(vi->dev, "failed to request syncpoint\n");
> +		ret = -ENOMEM;
> +		goto host1x_sp_error;
> +	}
> +
> +	chan->queue.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +	chan->queue.io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ;
> +	chan->queue.lock = &chan->video_lock;
> +	chan->queue.drv_priv = chan;
> +	chan->queue.buf_struct_size = sizeof(struct tegra_channel_buffer);
> +	chan->queue.ops = &tegra_channel_queue_qops;
> +	chan->queue.mem_ops = &vb2_dma_contig_memops;
> +	chan->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
> +				   | V4L2_BUF_FLAG_TSTAMP_SRC_EOF;

Just drop V4L2_BUF_FLAG_TSTAMP_SRC_EOF, it's 0 anyway. It's not common practice
to set this.

> +	chan->queue.dev = vi->dev;
> +	ret = vb2_queue_init(&chan->queue);
> +	if (ret < 0) {
> +		dev_err(vi->dev,
> +			"failed to initialize VB2 queue, err: %d\n", ret);
> +		goto vb2_init_error;
> +	}
> +
> +	ret = video_register_device(&chan->video, VFL_TYPE_GRABBER, -1);
> +	if (ret < 0) {
> +		dev_err(&chan->video.dev,
> +			"failed to register video device, err: %d\n", ret);
> +		goto video_register_error;
> +	}
> +
> +	return 0;
> +
> +video_register_error:
> +	vb2_queue_release(&chan->queue);
> +vb2_init_error:
> +	host1x_syncpt_free(chan->sp);
> +host1x_sp_error:
> +	v4l2_ctrl_handler_free(&chan->ctrl_handler);
> +ctrl_init_error:
> +	media_entity_cleanup(&chan->video.entity);
> +	return ret;
> +}
> +
> +int tegra_channel_cleanup(struct tegra_channel *chan)
> +{
> +	if (video_is_registered(&chan->video)) {
> +		video_unregister_device(&chan->video);
> +		vb2_queue_release(&chan->queue);
> +		media_entity_cleanup(&chan->video.entity);
> +	}
> +
> +	host1x_syncpt_free(chan->sp);
> +	v4l2_ctrl_handler_free(&chan->ctrl_handler);
> +
> +	return 0;
> +}
> diff --git a/drivers/staging/media/tegra/tegra-core.c b/drivers/staging/media/tegra/tegra-core.c
> new file mode 100644
> index 000000000000..80ede3ad7266
> --- /dev/null
> +++ b/drivers/staging/media/tegra/tegra-core.c
> @@ -0,0 +1,111 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#include <linux/export.h>
> +#include <linux/kernel.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +
> +#include "mc_common.h"
> +#include "tegra-core.h"
> +
> +static const struct tegra_video_format tegra_default_format = {
> +	/* RAW 10 */
> +	TEGRA_VF_RAW10,
> +	10,
> +	MEDIA_BUS_FMT_SRGGB10_1X10,
> +	{2, 1},
> +	TEGRA_IMAGE_FORMAT_DEF,
> +	TEGRA_IMAGE_DT_RAW10,
> +	V4L2_PIX_FMT_SRGGB10,
> +	"RGRG.. GBGB..",

Is this string used anywhere? The v4l2 core automatically sets the pixelformat
description for you in VIDIOC_ENUMFMT these days.

> +};
> +
> +/*
> + * Helper functions
> + */
> +
> +/**
> + * tegra_core_get_default_format - Get default format
> + *
> + * Return: pointer to the format where the default format needs
> + * to be filled in.
> + */
> +const struct tegra_video_format *tegra_core_get_default_format(void)
> +{
> +	return &tegra_default_format;
> +}
> +
> +/**
> + * tegra_core_get_fourcc_by_idx - get fourcc of a tegra_video format
> + * @index: array index of the tegra_video_formats
> + *
> + * Return: fourcc code
> + */
> +u32 tegra_core_get_fourcc_by_idx(struct tegra_channel *chan,
> +				 unsigned int index)
> +{
> +	if (index >= chan->nformats)
> +		return -EINVAL;
> +
> +	return chan->video_formats[index].fourcc;
> +}
> +
> +/**
> + * tegra_core_get_word_count - Calculate word count
> + * @frame_width: number of pixels per line
> + * @fmt: Tegra Video format struct which has BPP information
> + *
> + * Return: word count number
> + */
> +u32 tegra_core_get_word_count(unsigned int frame_width,
> +			      const struct tegra_video_format *fmt)
> +{
> +	return frame_width * fmt->width / 8;
> +}
> +
> +/**
> + * tegra_core_get_idx_by_code - Retrieve index for a media bus code
> + * @chan: tegra_channel
> + * @code: the format media bus code
> + * @offset: offset in video formats from where to start the search
> + *
> + * Return: a index to the format information structure corresponding to the
> + * given V4L2 media bus format @code, or -1 if no corresponding format can
> + * be found.
> + */
> +int tegra_core_get_idx_by_code(struct tegra_channel *chan, unsigned int code,
> +			       unsigned int offset)
> +{
> +	unsigned int i;
> +
> +	for (i = offset; i < chan->nformats; ++i) {
> +		if (chan->video_formats[i].code == code)
> +			return i;
> +	}
> +
> +	return -1;
> +}
> +
> +/**
> + * tegra_core_get_format_by_fourcc - Retrieve format information for a 4CC
> + * @fourcc: the format 4CC
> + *
> + * Return: a pointer to the format information structure corresponding to the
> + * given V4L2 format @fourcc, or NULL if no corresponding format can be
> + * found.
> + */
> +const struct tegra_video_format *
> +tegra_core_get_format_by_fourcc(struct tegra_channel *chan, u32 fourcc)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < chan->nformats; ++i) {
> +		if (chan->video_formats[i].fourcc == fourcc)
> +			return &chan->video_formats[i];
> +	}
> +
> +	return NULL;
> +}
> diff --git a/drivers/staging/media/tegra/tegra-core.h b/drivers/staging/media/tegra/tegra-core.h
> new file mode 100644
> index 000000000000..193065d20a95
> --- /dev/null
> +++ b/drivers/staging/media/tegra/tegra-core.h
> @@ -0,0 +1,125 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#ifndef __TEGRA_CORE_H__
> +#define __TEGRA_CORE_H__
> +
> +#include <media/v4l2-subdev.h>
> +
> +/* Minimum and maximum width and height common to Tegra video input device. */
> +#define TEGRA_MIN_WIDTH		32U
> +#define TEGRA_MAX_WIDTH		32768U
> +#define TEGRA_MIN_HEIGHT	32U
> +#define TEGRA_MAX_HEIGHT	32768U
> +
> +/* Width alignment */
> +#define TEGRA_WIDTH_ALIGNMENT	1
> +/* Stride alignment */
> +#define TEGRA_STRIDE_ALIGNMENT	1
> +/* Height alignment */
> +#define TEGRA_HEIGHT_ALIGNMENT	1
> +/* Size alignment */
> +#define TEGRA_SIZE_ALIGNMENT	1
> +
> +/* 1080p resolution as default resolution for test pattern generator */
> +#define TEGRA_DEF_WIDTH		1920
> +#define TEGRA_DEF_HEIGHT	1080
> +
> +#define TEGRA_VF_DEF		MEDIA_BUS_FMT_SRGGB10_1X10
> +#define TEGRA_IMAGE_FORMAT_DEF	32
> +
> +/*
> + * These go into the TEGRA_VI_CSI_n_CSI_IMAGE_DT registers bits 7:0
> + * Input data type of VI channel.
> + */
> +enum tegra_image_dt {
> +	TEGRA_IMAGE_DT_YUV420_8 = 24,
> +	TEGRA_IMAGE_DT_YUV420_10,
> +
> +	TEGRA_IMAGE_DT_YUV420CSPS_8 = 28,
> +	TEGRA_IMAGE_DT_YUV420CSPS_10,
> +	TEGRA_IMAGE_DT_YUV422_8,
> +	TEGRA_IMAGE_DT_YUV422_10,
> +	TEGRA_IMAGE_DT_RGB444,
> +	TEGRA_IMAGE_DT_RGB555,
> +	TEGRA_IMAGE_DT_RGB565,
> +	TEGRA_IMAGE_DT_RGB666,
> +	TEGRA_IMAGE_DT_RGB888,
> +
> +	TEGRA_IMAGE_DT_RAW6 = 40,
> +	TEGRA_IMAGE_DT_RAW7,
> +	TEGRA_IMAGE_DT_RAW8,
> +	TEGRA_IMAGE_DT_RAW10,
> +	TEGRA_IMAGE_DT_RAW12,
> +	TEGRA_IMAGE_DT_RAW14,
> +};
> +
> +/* Supported CSI to VI Data Formats */
> +enum tegra_vf_code {
> +	TEGRA_VF_RAW6 = 0,
> +	TEGRA_VF_RAW7,
> +	TEGRA_VF_RAW8,
> +	TEGRA_VF_RAW10,
> +	TEGRA_VF_RAW12,
> +	TEGRA_VF_RAW14,
> +	TEGRA_VF_EMBEDDED8,
> +	TEGRA_VF_RGB565,
> +	TEGRA_VF_RGB555,
> +	TEGRA_VF_RGB888,
> +	TEGRA_VF_RGB444,
> +	TEGRA_VF_RGB666,
> +	TEGRA_VF_YUV422,
> +	TEGRA_VF_YUV420,
> +	TEGRA_VF_YUV420_CSPS,
> +};
> +
> +/**
> + * struct tegra_frac
> + * @numerator: numerator of the fraction
> + * @denominator: denominator of the fraction
> + */
> +struct tegra_frac {
> +	unsigned int numerator;
> +	unsigned int denominator;
> +};
> +
> +/**
> + * struct tegra_video_format - Tegra video format description
> + * @vf_code: video format code
> + * @width: format width in bits per component
> + * @code: media bus format code
> + * @bpp: bytes per pixel (when stored in memory)
> + * @img_fmt: image format
> + * @img_dt: image data type
> + * @fourcc: V4L2 pixel format FCC identifier
> + * @description: format description, suitable for userspace

As mentioned above: this is almost certainly no longer needed.

> + */
> +struct tegra_video_format {
> +	enum tegra_vf_code vf_code;
> +	unsigned int width;
> +	unsigned int code;
> +	struct tegra_frac bpp;
> +	u32 img_fmt;
> +	enum tegra_image_dt img_dt;
> +	u32 fourcc;
> +	__u8 description[32];
> +};
> +
> +#define	TEGRA_VIDEO_FORMAT(VF_CODE, BPP, MBUS_CODE, FRAC_BPP_NUM,	\
> +	FRAC_BPP_DEN, FORMAT, DATA_TYPE, FOURCC, DESCRIPTION)		\
> +{									\
> +	TEGRA_VF_##VF_CODE,						\
> +	BPP,								\
> +	MEDIA_BUS_FMT_##MBUS_CODE,					\
> +	{FRAC_BPP_NUM, FRAC_BPP_DEN},					\
> +	TEGRA_IMAGE_FORMAT_##FORMAT,					\
> +	TEGRA_IMAGE_DT_##DATA_TYPE,					\
> +	V4L2_PIX_FMT_##FOURCC,						\
> +	DESCRIPTION,							\
> +}
> +
> +u32 tegra_core_get_word_count(unsigned int frame_width,
> +			      const struct tegra_video_format *fmt);
> +#endif
> diff --git a/drivers/staging/media/tegra/tegra-csi.c b/drivers/staging/media/tegra/tegra-csi.c
> new file mode 100644
> index 000000000000..f6153acd60cb
> --- /dev/null
> +++ b/drivers/staging/media/tegra/tegra-csi.c
> @@ -0,0 +1,380 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/clk/tegra.h>
> +#include <linux/device.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/host1x.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_platform.h>
> +
> +#include "csi.h"
> +#include "mc_common.h"
> +#include "csi2_fops.h"
> +#include "host1x-video.h"
> +#include "vi2_registers.h"
> +
> +static inline struct tegra_csi_device *
> +host1x_client_to_csi(struct host1x_client *client)
> +{
> +	return container_of(client, struct tegra_csi_device, client);
> +}
> +
> +static inline struct tegra_csi_channel *to_csi_chan(struct v4l2_subdev *subdev)
> +{
> +	return container_of(subdev, struct tegra_csi_channel, subdev);
> +}
> +
> +/*
> + * V4L2 Subdevice Video Operations
> + */
> +static int tegra_csi_s_stream(struct v4l2_subdev *subdev, int enable)
> +{
> +	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
> +	struct tegra_csi_device *csi = csi_chan->csi;
> +	struct tegra_channel *chan = subdev->host_priv;
> +	u8 pg_mode = chan->vi->pg_mode;
> +
> +	return csi->fops->csi_start_streaming(csi_chan, pg_mode, enable);
> +}
> +
> +/*
> + * Only use this subdevice media bus ops for test pattern generator,
> + * because CSI device is an separated subdevice which has 6 source
> + * pads to generate test pattern.
> + */
> +static struct v4l2_mbus_framefmt tegra_csi_tpg_fmts[] = {
> +	{
> +		TEGRA_DEF_WIDTH,
> +		TEGRA_DEF_HEIGHT,
> +		MEDIA_BUS_FMT_SRGGB10_1X10,
> +		V4L2_FIELD_NONE,
> +		V4L2_COLORSPACE_SRGB
> +	},
> +	{
> +		TEGRA_DEF_WIDTH,
> +		TEGRA_DEF_HEIGHT,
> +		MEDIA_BUS_FMT_RGB888_1X32_PADHI,
> +		V4L2_FIELD_NONE,
> +		V4L2_COLORSPACE_SRGB
> +	}
> +
> +};
> +
> +static struct v4l2_frmsize_discrete tegra_csi_tpg_sizes[] = {
> +	{1280, 720},
> +	{1920, 1080},
> +	{3840, 2160},
> +};
> +
> +/*
> + * V4L2 Subdevice Pad Operations
> + */
> +static int tegra_csi_get_format(struct v4l2_subdev *subdev,
> +				struct v4l2_subdev_pad_config *cfg,
> +				struct v4l2_subdev_format *fmt)
> +{
> +	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
> +
> +	mutex_lock(&csi_chan->format_lock);
> +	memcpy(fmt, &csi_chan->ports->format,
> +	       sizeof(struct v4l2_mbus_framefmt));
> +	mutex_unlock(&csi_chan->format_lock);
> +
> +	return 0;
> +}
> +
> +static void tegra_csi_try_mbus_fmt(struct v4l2_subdev *subdev,
> +				   struct v4l2_mbus_framefmt *mfmt)
> +{
> +	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
> +	struct tegra_csi_device *csi = csi_chan->csi;
> +	const struct v4l2_frmsize_discrete *sizes;
> +	int i, j;
> +
> +	for (i = 0; i < ARRAY_SIZE(tegra_csi_tpg_fmts); i++) {
> +		struct v4l2_mbus_framefmt *mbus_fmt = &tegra_csi_tpg_fmts[i];
> +
> +		if (mfmt->code == mbus_fmt->code) {
> +			for (j = 0; j < ARRAY_SIZE(tegra_csi_tpg_sizes); j++) {
> +				sizes = &tegra_csi_tpg_sizes[j];
> +				if (mfmt->width == sizes->width &&
> +				    mfmt->height == sizes->height) {
> +					return;
> +				}
> +			}
> +		}
> +
> +		dev_info(csi->dev, "using Tegra default RAW10 video format\n");
> +	}
> +
> +	dev_info(csi->dev, "using Tegra default WIDTH X HEIGHT (1920x1080)\n");
> +	memcpy(mfmt, tegra_csi_tpg_fmts, sizeof(struct v4l2_mbus_framefmt));
> +}
> +
> +static int tegra_csi_set_format(struct v4l2_subdev *subdev,
> +				struct v4l2_subdev_pad_config *cfg,
> +				struct v4l2_subdev_format *fmt)
> +{
> +	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
> +	struct v4l2_mbus_framefmt *format = &fmt->format;
> +
> +	tegra_csi_try_mbus_fmt(subdev, format);
> +
> +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> +		return 0;
> +
> +	mutex_lock(&csi_chan->format_lock);
> +	memcpy(&csi_chan->ports->format, format,
> +	       sizeof(struct v4l2_mbus_framefmt));

Just do: csi_chan->ports->format = *format;

> +	mutex_unlock(&csi_chan->format_lock);
> +
> +	return 0;
> +}
> +
> +/*
> + * V4L2 Subdevice Operations
> + */
> +static struct v4l2_subdev_video_ops tegra_csi_video_ops = {
> +	.s_stream = tegra_csi_s_stream,
> +};
> +
> +static struct v4l2_subdev_pad_ops tegra_csi_pad_ops = {
> +	.get_fmt		= tegra_csi_get_format,
> +	.set_fmt		= tegra_csi_set_format,
> +};
> +
> +static struct v4l2_subdev_ops tegra_csi_ops = {
> +	.video  = &tegra_csi_video_ops,
> +	.pad    = &tegra_csi_pad_ops,
> +};
> +
> +/*
> + * Media Operations
> + */
> +static const struct media_entity_operations tegra_csi_media_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static int tegra_csi_tpg_channels_alloc(struct tegra_csi_device *csi)
> +{
> +	struct device_node *node = csi->dev->of_node;
> +	unsigned int port_num;
> +	int ret;
> +	struct tegra_csi_channel *item;
> +	unsigned int tpg_channels = csi->soc_data->num_tpg_channels;
> +
> +	/* allocate CSI channel for each CSI x2 ports */
> +	for (port_num = 0; port_num < tpg_channels; port_num++) {
> +		item = devm_kzalloc(csi->dev, sizeof(*item), GFP_KERNEL);
> +		if (!item) {
> +			ret = -ENOMEM;
> +			goto error;
> +		}
> +
> +		list_add_tail(&item->list, &csi->csi_chans);
> +		item->csi = csi;
> +		item->csi_port_num = port_num;
> +		item->numlanes = 2;
> +		item->of_node = node;
> +		item->numpads = 1;
> +		item->pads[0].flags = MEDIA_PAD_FL_SOURCE;
> +	}
> +
> +	return 0;
> +
> +error:
> +	list_for_each_entry(item, &csi->csi_chans, list)
> +		list_del(&item->list);
> +
> +	return ret;
> +}
> +
> +static int tegra_csi_channel_init(struct tegra_csi_channel *chan)
> +{
> +	struct tegra_csi_device *csi = chan->csi;
> +	struct v4l2_subdev *subdev;
> +	int ret;
> +
> +	chan->ports = devm_kzalloc(csi->dev, sizeof(struct tegra_csi_port),
> +				   GFP_KERNEL);
> +	if (!chan->ports)
> +		return -ENOMEM;
> +
> +	mutex_init(&chan->format_lock);
> +
> +	/* initialize the default format */
> +	chan->ports->format.code = TEGRA_VF_DEF;
> +	chan->ports->format.field = V4L2_FIELD_NONE;
> +	chan->ports->format.colorspace = V4L2_COLORSPACE_SRGB;
> +	chan->ports->format.width = TEGRA_DEF_WIDTH;
> +	chan->ports->format.height = TEGRA_DEF_HEIGHT;
> +	chan->ports->lanes = chan->numlanes;
> +
> +	/* initialize V4L2 subdevice and media entity */
> +	subdev = &chan->subdev;
> +	v4l2_subdev_init(subdev, &tegra_csi_ops);
> +	subdev->dev = csi->dev;
> +	snprintf(subdev->name, V4L2_SUBDEV_NAME_SIZE, "%s-%d", "tpg",
> +		 chan->csi_port_num);
> +
> +	v4l2_set_subdevdata(subdev, chan);
> +	subdev->fwnode = of_fwnode_handle(chan->of_node);
> +	subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	subdev->entity.ops = &tegra_csi_media_ops;
> +
> +	/* initialize media entity pads */
> +	ret = media_entity_pads_init(&subdev->entity, chan->numpads,
> +				     chan->pads);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = v4l2_async_register_subdev(subdev);
> +	if (ret < 0) {
> +		dev_err(csi->dev, "failed to register subdev\n");
> +		media_entity_cleanup(&subdev->entity);
> +	}
> +
> +	return ret;
> +}
> +
> +void tegra_csi_error_status(struct v4l2_subdev *subdev)
> +{
> +	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
> +	struct tegra_csi_device *csi = csi_chan->csi;
> +
> +	csi->fops->csi_err_status(csi_chan);
> +}
> +EXPORT_SYMBOL(tegra_csi_error_status);
> +
> +static int tegra_csi_init(struct host1x_client *client)
> +{
> +	struct tegra_csi_device *csi = host1x_client_to_csi(client);
> +	struct tegra_camera *cam = dev_get_drvdata(client->host);
> +	struct tegra_csi_channel *item;
> +	int ret;
> +
> +	cam->csi = csi;
> +
> +	INIT_LIST_HEAD(&csi->csi_chans);
> +
> +	ret = tegra_csi_tpg_channels_alloc(csi);
> +	if (ret < 0)
> +		return ret;
> +
> +	list_for_each_entry(item, &csi->csi_chans, list) {
> +		ret = tegra_csi_channel_init(item);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	ret = csi->fops->hw_init(csi);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int tegra_csi_exit(struct host1x_client *client)
> +{
> +	struct tegra_camera *cam = dev_get_drvdata(client->host);
> +	struct v4l2_subdev *subdev;
> +	struct tegra_csi_channel *chan;
> +
> +	if (!cam->csi)
> +		return 0;
> +
> +	list_for_each_entry(chan, &cam->csi->csi_chans, list) {
> +		mutex_destroy(&chan->format_lock);
> +		subdev = &chan->subdev;
> +		media_entity_cleanup(&subdev->entity);
> +		v4l2_async_unregister_subdev(subdev);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct host1x_client_ops csi_client_ops = {
> +	.init = tegra_csi_init,
> +	.exit = tegra_csi_exit,
> +};
> +
> +static int tegra_csi_probe(struct platform_device *pdev)
> +{
> +	struct tegra_csi_device *csi;
> +	struct resource *res;
> +	int ret;
> +
> +	csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
> +	if (!csi)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	csi->iomem = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(csi->iomem))
> +		return PTR_ERR(csi->iomem);
> +
> +	csi->soc_data = of_device_get_match_data(&pdev->dev);
> +	if (!csi->soc_data) {
> +		dev_info(&pdev->dev, "No platform data\n\n");
> +		return -ENODATA;
> +	}
> +
> +	csi->dev = &pdev->dev;
> +	csi->fops = csi->soc_data->csi_fops;
> +	platform_set_drvdata(pdev, csi);
> +
> +	/* initialize host1x interface */
> +	INIT_LIST_HEAD(&csi->client.list);
> +	csi->client.ops = &csi_client_ops;
> +	csi->client.dev = &pdev->dev;
> +
> +	ret = host1x_client_register(&csi->client);
> +	if (ret < 0) {
> +		dev_err(csi->dev, "failed to register host1x client: %d\n",
> +			ret);
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tegra_csi_remove(struct platform_device *pdev)
> +{
> +	struct tegra_csi_device *csi = platform_get_drvdata(pdev);
> +
> +	host1x_client_unregister(&csi->client);
> +
> +	return 0;
> +}
> +
> +static struct tegra_csi_soc_data tegra210_csi_data = {
> +	.csi_fops = &csi2_fops,
> +	.cil_max_clk_hz = TEGRA210_CSI_CIL_CLK_MAX,
> +	.num_tpg_channels = TEGRA210_MAX_CHANNELS,
> +};
> +
> +static const struct of_device_id tegra_csi_of_id_table[] = {
> +	{ .compatible = "nvidia,tegra210-csi", .data = &tegra210_csi_data },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, tegra_csi_of_id_table);
> +
> +struct platform_driver tegra_csi_driver = {
> +	.driver = {
> +		.name		= "tegra-csi",
> +		.of_match_table	= tegra_csi_of_id_table,
> +	},
> +	.probe			= tegra_csi_probe,
> +	.remove			= tegra_csi_remove,
> +};
> +
> +MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@nvidia.com>");
> +MODULE_DESCRIPTION("NVIDIA Tegra CSI Device Driver");
> +MODULE_LICENSE("GPL v2");

<snip>

This is just from a quick review. I see a number of areas that I want
to discuss in more detail, I hope to get to that tomorrow or Friday at
the latest. I'm currently trying to setup my Jetson TX1 board so I can
test this series.

Regards,

	Hans