From: Sowjanya Komatineni <skomatineni@nvidia.com>
To: "Hans Verkuil (hansverk)" <hansverk@cisco.com>,
"thierry.reding@gmail.com" <thierry.reding@gmail.com>,
"jonathanh@nvidia.com" <jonathanh@nvidia.com>,
"frankc@nvidia.com" <frankc@nvidia.com>
Cc: "linux-media@vger.kernel.org" <linux-media@vger.kernel.org>,
"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
"linux-clk@vger.kernel.org" <linux-clk@vger.kernel.org>,
"linux-tegra@vger.kernel.org" <linux-tegra@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH v1 4/5] media: tegra: Add Tegra Video input driver for Tegra210
Date: Wed, 29 Jan 2020 09:27:18 -0800 [thread overview]
Message-ID: <0867e6bc-a42d-93cd-f3da-e46b250739c9@nvidia.com> (raw)
In-Reply-To: <3cec464f-730f-97be-0000-05b6c04f346f@cisco.com>
Thanks Hans. Will fix in v2 based on below feedback.
On 1/29/20 6:16 AM, Hans Verkuil (hansverk) wrote:
> External email: Use caution opening links or attachments
>
>
> 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
next prev parent reply other threads:[~2020-01-29 17:27 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-28 18:23 [RFC PATCH v1 0/5] Add Tegra driver for video capture Sowjanya Komatineni
2020-01-28 18:23 ` [RFC PATCH v1 1/5] dt-bindings: clock: tegra: Add clk id for CSI TPG clock Sowjanya Komatineni
2020-02-05 19:23 ` Stephen Boyd
2020-01-28 18:23 ` [RFC PATCH v1 2/5] clk: tegra: Add Tegra210 CSI TPG clock gate Sowjanya Komatineni
2020-02-05 19:23 ` Stephen Boyd
2020-01-28 18:23 ` [RFC PATCH v1 3/5] dt-binding: tegra: Add VI and CSI bindings Sowjanya Komatineni
2020-01-28 20:32 ` Helen Koike
2020-01-28 21:04 ` Sowjanya Komatineni
2020-01-28 18:23 ` [RFC PATCH v1 4/5] media: tegra: Add Tegra Video input driver for Tegra210 Sowjanya Komatineni
2020-01-28 21:45 ` Helen Koike
2020-01-28 22:13 ` Sowjanya Komatineni
2020-01-29 0:49 ` Sowjanya Komatineni
2020-01-29 1:05 ` Helen Koike
2020-01-29 2:11 ` Sowjanya Komatineni
2020-01-29 5:59 ` Sowjanya Komatineni
2020-01-29 10:31 ` Helen Koike
2020-01-29 17:49 ` Sowjanya Komatineni
2020-01-29 18:15 ` Sowjanya Komatineni
2020-01-29 18:46 ` Helen Koike
2020-01-29 22:40 ` Sowjanya Komatineni
2020-01-29 18:29 ` Helen Koike
2020-01-29 18:46 ` Sowjanya Komatineni
2020-01-29 10:09 ` Thierry Reding
2020-01-29 16:25 ` Sowjanya Komatineni
2020-01-29 11:13 ` Thierry Reding
2020-01-29 17:23 ` Sowjanya Komatineni
2020-01-30 12:20 ` Thierry Reding
2020-01-30 17:02 ` Sowjanya Komatineni
2020-01-29 14:16 ` Hans Verkuil (hansverk)
2020-01-29 17:27 ` Sowjanya Komatineni [this message]
2020-01-30 14:45 ` Hans Verkuil
2020-02-05 19:26 ` Stephen Boyd
2020-02-05 19:54 ` Sowjanya Komatineni
2020-01-28 18:23 ` [RFC PATCH v1 5/5] arm64: tegra: Add Tegra VI CSI suppport in device tree Sowjanya Komatineni
2020-01-29 9:46 ` Thierry Reding
2020-01-29 16:22 ` Sowjanya Komatineni
2020-01-30 12:36 ` Thierry Reding
2020-01-30 17:18 ` Sowjanya Komatineni
2020-01-30 17:58 ` Thierry Reding
2020-01-30 18:58 ` Sowjanya Komatineni
2020-01-30 20:18 ` Sowjanya Komatineni
2020-01-31 2:57 ` Sowjanya Komatineni
2020-01-30 14:41 ` [RFC PATCH v1 0/5] Add Tegra driver for video capture Hans Verkuil
2020-01-30 15:42 ` Thierry Reding
2020-01-31 14:29 ` Hans Verkuil
2020-01-31 17:03 ` Thierry Reding
2020-01-31 17:37 ` Hans Verkuil
2020-01-31 20:31 ` Thierry Reding
2020-02-04 9:50 ` Hans Verkuil
2020-01-30 17:20 ` Sowjanya Komatineni
2020-02-04 12:53 ` Hans Verkuil
2020-02-04 16:42 ` Sowjanya Komatineni
2020-02-04 17:22 ` Hans Verkuil
2020-02-04 19:02 ` Sowjanya Komatineni
2020-02-05 7:57 ` Hans Verkuil
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0867e6bc-a42d-93cd-f3da-e46b250739c9@nvidia.com \
--to=skomatineni@nvidia.com \
--cc=devicetree@vger.kernel.org \
--cc=frankc@nvidia.com \
--cc=hansverk@cisco.com \
--cc=jonathanh@nvidia.com \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=thierry.reding@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).