Re: [PATCH v9 2/4] media: i2c: Add MAX9286 driver

From: Manivannan Sadhasivam
Date: Thu May 14 2020 - 06:00:12 EST


On Thu, May 14, 2020 at 10:53:00AM +0100, Kieran Bingham wrote:
> Hi Mani,
>
> On 12/05/2020 18:40, Manivannan Sadhasivam wrote:
> > Hi Kieran,
> >
> > On Tue, May 12, 2020 at 04:51:03PM +0100, Kieran Bingham wrote:
> >> The MAX9286 is a 4-channel GMSL deserializer with coax or STP input and
> >> CSI-2 output. The device supports multicamera streaming applications,
> >> and features the ability to synchronise the attached cameras.
> >>
> >> CSI-2 output can be configured with 1 to 4 lanes, and a control channel
> >> is supported over I2C, which implements an I2C mux to facilitate
> >> communications with connected cameras across the reverse control
> >> channel.
> >>
> >> Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> >> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> >> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> >> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> >>
> >> --
> >> v2:
> >> - Fix MAINTAINERS entry
> >>
> >> This posting is released with the following modifications to work
> >> without Sakari's VC developments:
> >> - max9286_g_mbus_config() re-instated
> >> - max9286_get_frame_desc() is not bus/csi aware
> >> - max9286_{get,set}_routing() removed
> >>
> >> v3:
> >> - Initialise notifier with v4l2_async_notifier_init
> >> - Update for new mbus csi2 format V4L2_MBUS_CSI2_DPHY
> >>
> >> v4: - Re-introduce required code to function with the VC series.
> >>
> >> - Implement max9286_get_routing, max9286_set_routing
> >> - Remove max9286_g_mbus_config
> >>
> >> v5: (internal release)
> >> - Fix printk formatting for hex value
> >> - max9286->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE (add |)
> >> - MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER -> MEDIA_ENT_F_VID_IF_BRIDGE
> >> - Remove 'device is bound' workaround
> >>
> >> v6:
> >> - v4l2_subdev_krouting instead of v4l2_subdev_routing separated
> >> to allow integration without the VC/V4L2-Mux series.
> >> - convert sd_to_max9286 to inline function
> >> - rename max9286_device to max9286_priv
> >> - Cleanup the v4l2_async_notifier
> >> - Extend MODULE_AUTHOR
> >> - Replace of_graph_get_endpoint_by_regs with fwnode_graph_get_endpoint_by_id
> >> - Pass default bus type when parsing fwnode endpoint (Manivannan Sadhasivam)
> >> - Use new YAML file reference in MAINTAINERS
> >> - Parse new i2c-mux node in max9286_get_i2c_by_id
> >> (This could/should be refactored to parse these separately first)
> >> - Spelling and calculation fixes in the FSYNC_LOCKED check comments
> >> - Identify each enabled i2c-mux channel in a single pass
> >> - max9286: Improve mux-state readbility [v2]
> >> - Fix frame sync lock durations
> >> - Add comment to describe /why/ we must open the mux in s_stream
> >> - use -EXDEV as return code for failed link synchronisation.
> >> - Fix reference counting of the dt nodeS
> >> - Convert to probe_new for I2C
> >> - Remove redundant max9286_i2c_mux_state
> >> - Provide optional enable-gpio (max9286-pwdn)
> >>
> >> v7:
> >> [Kieran]
> >> - Ensure powerdown lines are optional
> >> - Add a 4ms power-up delay
> >> - Add max9286_check_config_link() to core
> >> - Add GPIO chip controller for GPIO0OUT and GPIO1OUT
> >> - Fix GPIO registration
> >> - max9286: Split out async registration
> >> (fixes regulator -EPROBE_DEFERs failures)
> >> - Collect all V4L2 registrations
> >> - balance v4l2_async refcnting
> >> - Rename max9286_v4l2_async_ => max9286_v4l2_notifier_
> >>
> >> [Jacopo]
> >> - Remove redundanct MAXIM_I2C_SPEED macros
> >> - Move notifiers operations
> >> - Add delay after reverse channel reconfiguration
> >> - Move link setup to completion
> >> - Fix up max9286_check_config_link() implementation
> >> - Remove redundant dual configuration of reverse channel
> >>
> >> v8:
> >>
> >> [Kieran]
> >> - Update the bound_sources mask on unbind
> >> - Convert probe kzalloc usage to devm_ variant
> >> - Fix up cleanup path from GPIO PowerDown registration
> >> - cleanup GPIO device registration fail path
> >> - Convert to use devm_regulator_get()
> >> - Fit max9286_parse_dt print on one line
> >> - Move multi-device workarounds out of upstream driver
> >> - Remove I2C mod-table
> >> - Lock format changes
> >> - Describe pad index usage
> >> - Remove poc_enabled workaround
> >> - Rename the max9286_gpio to be more explicit on it's actions.
> >> - Move max9286_init_format call
> >> - Rework probe sequence and simplify error paths.
> >> - Simplify i2c comments
> >> - Implement Pixelrate control
> >> - Disable overlap window
> >>
> >> [Jacopo]
> >> - Adapt Kconfig to latest upstream changes
> >> - Put of node on error
> >> - Calculate pixel rate
> >> - Simplify overlap window disablement
> >>
> >> v9:
> >>
> >> [Kieran]
> >> - Kconfig: Depend on OF
> >> - Re-sort addition to Makefile
> >> ---
> >> MAINTAINERS | 10 +
> >> drivers/media/i2c/Kconfig | 13 +
> >> drivers/media/i2c/Makefile | 1 +
> >> drivers/media/i2c/max9286.c | 1332 +++++++++++++++++++++++++++++++++++
> >> 4 files changed, 1356 insertions(+)
> >> create mode 100644 drivers/media/i2c/max9286.c
> >>
> >> diff --git a/MAINTAINERS b/MAINTAINERS
> >> index a7bb6e22d5da..99e3bf7760fd 100644
> >> --- a/MAINTAINERS
> >> +++ b/MAINTAINERS
> >> @@ -10274,6 +10274,16 @@ F: Documentation/hwmon/max6697.rst
> >> F: drivers/hwmon/max6697.c
> >> F: include/linux/platform_data/max6697.h
> >>
> >> +MAX9286 QUAD GMSL DESERIALIZER DRIVER
> >> +M: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> >> +M: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> >> +M: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> >> +M: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> >> +L: linux-media@xxxxxxxxxxxxxxx
> >> +S: Maintained
> >> +F: Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> >> +F: drivers/media/i2c/max9286.c
> >> +
> >> MAX9860 MONO AUDIO VOICE CODEC DRIVER
> >> M: Peter Rosin <peda@xxxxxxxxxx>
> >> L: alsa-devel@xxxxxxxxxxxxxxxx (moderated for non-subscribers)
> >> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> >> index 3abc80373ec0..2e390f41f6da 100644
> >> --- a/drivers/media/i2c/Kconfig
> >> +++ b/drivers/media/i2c/Kconfig
> >> @@ -464,6 +464,19 @@ config VIDEO_VPX3220
> >> To compile this driver as a module, choose M here: the
> >> module will be called vpx3220.
> >>
> >> +config VIDEO_MAX9286
> >> + tristate "Maxim MAX9286 GMSL deserializer support"
> >> + depends on I2C && I2C_MUX
> >> + depends on OF
> >> + select V4L2_FWNODE
> >> + select VIDEO_V4L2_SUBDEV_API
> >> + select MEDIA_CONTROLLER
> >> + help
> >> + This driver supports the Maxim MAX9286 GMSL deserializer.
> >> +
> >> + To compile this driver as a module, choose M here: the
> >> + module will be called max9286.
> >> +
> >> comment "Video and audio decoders"
> >>
> >> config VIDEO_SAA717X
> >> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> >> index 77bf7d0b691f..f0b001ee4b05 100644
> >> --- a/drivers/media/i2c/Makefile
> >> +++ b/drivers/media/i2c/Makefile
> >> @@ -117,6 +117,7 @@ obj-$(CONFIG_VIDEO_IMX274) += imx274.o
> >> obj-$(CONFIG_VIDEO_IMX290) += imx290.o
> >> obj-$(CONFIG_VIDEO_IMX319) += imx319.o
> >> obj-$(CONFIG_VIDEO_IMX355) += imx355.o
> >> +obj-$(CONFIG_VIDEO_MAX9286) += max9286.o
> >> obj-$(CONFIG_VIDEO_ST_MIPID02) += st-mipid02.o
> >>
> >> obj-$(CONFIG_SDR_MAX2175) += max2175.o
> >> diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
> >> new file mode 100644
> >> index 000000000000..481d65f2b51d
> >> --- /dev/null
> >> +++ b/drivers/media/i2c/max9286.c
> >> @@ -0,0 +1,1332 @@
> >> +// SPDX-License-Identifier: GPL-2.0+
> >> +/*
> >> + * Maxim MAX9286 GMSL Deserializer Driver
> >> + *
> >> + * Copyright (C) 2017-2019 Jacopo Mondi
> >> + * Copyright (C) 2017-2019 Kieran Bingham
> >> + * Copyright (C) 2017-2019 Laurent Pinchart
> >> + * Copyright (C) 2017-2019 Niklas Söderlund
> >> + * Copyright (C) 2016 Renesas Electronics Corporation
> >> + * Copyright (C) 2015 Cogent Embedded, Inc.
> >> + */
> >> +
> >> +#include <linux/delay.h>
> >> +#include <linux/device.h>
> >> +#include <linux/fwnode.h>
> >> +#include <linux/gpio/consumer.h>
> >> +#include <linux/gpio/driver.h>
> >> +#include <linux/i2c.h>
> >> +#include <linux/i2c-mux.h>
> >> +#include <linux/module.h>
> >> +#include <linux/mutex.h>
> >> +#include <linux/of_graph.h>
> >> +#include <linux/regulator/consumer.h>
> >> +#include <linux/slab.h>
> >> +
> >> +#include <media/v4l2-async.h>
> >> +#include <media/v4l2-ctrls.h>
> >> +#include <media/v4l2-device.h>
> >> +#include <media/v4l2-fwnode.h>
> >> +#include <media/v4l2-subdev.h>
> >> +
> >> +/* Register 0x00 */
> >> +#define MAX9286_MSTLINKSEL_AUTO (7 << 5)
> >> +#define MAX9286_MSTLINKSEL(n) ((n) << 5)
> >> +#define MAX9286_EN_VS_GEN BIT(4)
> >> +#define MAX9286_LINKEN(n) (1 << (n))
> >> +/* Register 0x01 */
> >> +#define MAX9286_FSYNCMODE_ECU (3 << 6)
> >> +#define MAX9286_FSYNCMODE_EXT (2 << 6)
> >> +#define MAX9286_FSYNCMODE_INT_OUT (1 << 6)
> >> +#define MAX9286_FSYNCMODE_INT_HIZ (0 << 6)
> >> +#define MAX9286_GPIEN BIT(5)
> >> +#define MAX9286_ENLMO_RSTFSYNC BIT(2)
> >> +#define MAX9286_FSYNCMETH_AUTO (2 << 0)
> >> +#define MAX9286_FSYNCMETH_SEMI_AUTO (1 << 0)
> >> +#define MAX9286_FSYNCMETH_MANUAL (0 << 0)
> >> +#define MAX9286_REG_FSYNC_PERIOD_L 0x06
> >> +#define MAX9286_REG_FSYNC_PERIOD_M 0x07
> >> +#define MAX9286_REG_FSYNC_PERIOD_H 0x08
> >> +/* Register 0x0a */
> >> +#define MAX9286_FWDCCEN(n) (1 << ((n) + 4))
> >> +#define MAX9286_REVCCEN(n) (1 << (n))
> >> +/* Register 0x0c */
> >> +#define MAX9286_HVEN BIT(7)
> >> +#define MAX9286_EDC_6BIT_HAMMING (2 << 5)
> >> +#define MAX9286_EDC_6BIT_CRC (1 << 5)
> >> +#define MAX9286_EDC_1BIT_PARITY (0 << 5)
> >> +#define MAX9286_DESEL BIT(4)
> >> +#define MAX9286_INVVS BIT(3)
> >> +#define MAX9286_INVHS BIT(2)
> >> +#define MAX9286_HVSRC_D0 (2 << 0)
> >> +#define MAX9286_HVSRC_D14 (1 << 0)
> >> +#define MAX9286_HVSRC_D18 (0 << 0)
> >> +/* Register 0x0f */
> >> +#define MAX9286_0X0F_RESERVED BIT(3)
> >> +/* Register 0x12 */
> >> +#define MAX9286_CSILANECNT(n) (((n) - 1) << 6)
> >> +#define MAX9286_CSIDBL BIT(5)
> >> +#define MAX9286_DBL BIT(4)
> >> +#define MAX9286_DATATYPE_USER_8BIT (11 << 0)
> >> +#define MAX9286_DATATYPE_USER_YUV_12BIT (10 << 0)
> >> +#define MAX9286_DATATYPE_USER_24BIT (9 << 0)
> >> +#define MAX9286_DATATYPE_RAW14 (8 << 0)
> >> +#define MAX9286_DATATYPE_RAW11 (7 << 0)
> >> +#define MAX9286_DATATYPE_RAW10 (6 << 0)
> >> +#define MAX9286_DATATYPE_RAW8 (5 << 0)
> >> +#define MAX9286_DATATYPE_YUV422_10BIT (4 << 0)
> >> +#define MAX9286_DATATYPE_YUV422_8BIT (3 << 0)
> >> +#define MAX9286_DATATYPE_RGB555 (2 << 0)
> >> +#define MAX9286_DATATYPE_RGB565 (1 << 0)
> >> +#define MAX9286_DATATYPE_RGB888 (0 << 0)
> >> +/* Register 0x15 */
> >> +#define MAX9286_VC(n) ((n) << 5)
> >> +#define MAX9286_VCTYPE BIT(4)
> >> +#define MAX9286_CSIOUTEN BIT(3)
> >> +#define MAX9286_0X15_RESV (3 << 0)
> >> +/* Register 0x1b */
> >> +#define MAX9286_SWITCHIN(n) (1 << ((n) + 4))
> >> +#define MAX9286_ENEQ(n) (1 << (n))
> >> +/* Register 0x27 */
> >> +#define MAX9286_LOCKED BIT(7)
> >> +/* Register 0x31 */
> >> +#define MAX9286_FSYNC_LOCKED BIT(6)
> >> +/* Register 0x34 */
> >> +#define MAX9286_I2CLOCACK BIT(7)
> >> +#define MAX9286_I2CSLVSH_1046NS_469NS (3 << 5)
> >> +#define MAX9286_I2CSLVSH_938NS_352NS (2 << 5)
> >> +#define MAX9286_I2CSLVSH_469NS_234NS (1 << 5)
> >> +#define MAX9286_I2CSLVSH_352NS_117NS (0 << 5)
> >> +#define MAX9286_I2CMSTBT_837KBPS (7 << 2)
> >> +#define MAX9286_I2CMSTBT_533KBPS (6 << 2)
> >> +#define MAX9286_I2CMSTBT_339KBPS (5 << 2)
> >> +#define MAX9286_I2CMSTBT_173KBPS (4 << 2)
> >> +#define MAX9286_I2CMSTBT_105KBPS (3 << 2)
> >> +#define MAX9286_I2CMSTBT_84KBPS (2 << 2)
> >> +#define MAX9286_I2CMSTBT_28KBPS (1 << 2)
> >> +#define MAX9286_I2CMSTBT_8KBPS (0 << 2)
> >> +#define MAX9286_I2CSLVTO_NONE (3 << 0)
> >> +#define MAX9286_I2CSLVTO_1024US (2 << 0)
> >> +#define MAX9286_I2CSLVTO_256US (1 << 0)
> >> +#define MAX9286_I2CSLVTO_64US (0 << 0)
> >> +/* Register 0x3b */
> >> +#define MAX9286_REV_TRF(n) ((n) << 4)
> >> +#define MAX9286_REV_AMP(n) ((((n) - 30) / 10) << 1) /* in mV */
> >> +#define MAX9286_REV_AMP_X BIT(0)
> >> +/* Register 0x3f */
> >> +#define MAX9286_EN_REV_CFG BIT(6)
> >> +#define MAX9286_REV_FLEN(n) ((n) - 20)
> >> +/* Register 0x49 */
> >> +#define MAX9286_VIDEO_DETECT_MASK 0x0f
> >> +/* Register 0x69 */
> >> +#define MAX9286_LFLTBMONMASKED BIT(7)
> >> +#define MAX9286_LOCKMONMASKED BIT(6)
> >> +#define MAX9286_AUTOCOMBACKEN BIT(5)
> >> +#define MAX9286_AUTOMASKEN BIT(4)
> >> +#define MAX9286_MASKLINK(n) ((n) << 0)
> >> +
> >> +/*
> >> + * The sink and source pads are created to match the OF graph port numbers so
> >> + * that their indexes can be used interchangeably.
> >> + */
> >> +#define MAX9286_NUM_GMSL 4
> >> +#define MAX9286_N_SINKS 4
> >> +#define MAX9286_N_PADS 5
> >> +#define MAX9286_SRC_PAD 4
> >> +
> >> +struct max9286_source {
> >> + struct v4l2_async_subdev asd;
> >> + struct v4l2_subdev *sd;
> >> + struct fwnode_handle *fwnode;
> >> +};
> >> +
> >> +#define asd_to_max9286_source(_asd) \
> >> + container_of(_asd, struct max9286_source, asd)
> >> +
> >> +struct max9286_priv {
> >> + struct i2c_client *client;
> >> + struct gpio_desc *gpiod_pwdn;
> >> + struct v4l2_subdev sd;
> >> + struct media_pad pads[MAX9286_N_PADS];
> >> + struct regulator *regulator;
> >> +
> >> + struct gpio_chip gpio;
> >> + u8 gpio_state;
> >> +
> >> + struct i2c_mux_core *mux;
> >> + unsigned int mux_channel;
> >> + bool mux_open;
> >> +
> >> + struct v4l2_ctrl_handler ctrls;
> >> + struct v4l2_ctrl *pixelrate;
> >> +
> >> + struct v4l2_mbus_framefmt fmt[MAX9286_N_SINKS];
> >> +
> >> + /* Protects controls and fmt structures */
> >> + struct mutex mutex;
> >> +
> >> + unsigned int nsources;
> >> + unsigned int source_mask;
> >> + unsigned int route_mask;
> >> + unsigned int bound_sources;
> >> + unsigned int csi2_data_lanes;
> >> + struct max9286_source sources[MAX9286_NUM_GMSL];
> >> + struct v4l2_async_notifier notifier;
> >> +};
> >> +
[...]
> >> +static int max9286_enum_mbus_code(struct v4l2_subdev *sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_mbus_code_enum *code)
> >> +{
> >> + if (code->pad || code->index > 0)
> >> + return -EINVAL;
> >> +
> >> + code->code = MEDIA_BUS_FMT_UYVY8_2X8;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static struct v4l2_mbus_framefmt *
> >> +max9286_get_pad_format(struct max9286_priv *priv,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + unsigned int pad, u32 which)
> >> +{
> >> + switch (which) {
> >> + case V4L2_SUBDEV_FORMAT_TRY:
> >> + return v4l2_subdev_get_try_format(&priv->sd, cfg, pad);
> >> + case V4L2_SUBDEV_FORMAT_ACTIVE:
> >> + return &priv->fmt[pad];
> >> + default:
> >> + return NULL;
> >> + }
> >> +}
> >> +
> >> +static int max9286_set_fmt(struct v4l2_subdev *sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_format *format)
> >> +{
> >> + struct max9286_priv *priv = sd_to_max9286(sd);
> >> + struct v4l2_mbus_framefmt *cfg_fmt;
> >> +
> >> + if (format->pad >= MAX9286_SRC_PAD)
> >> + return -EINVAL;
> >> +
> >> + /* Refuse non YUV422 formats as we hardcode DT to 8 bit YUV422 */
> >> + switch (format->format.code) {
> >> + case MEDIA_BUS_FMT_UYVY8_2X8:
> >> + case MEDIA_BUS_FMT_VYUY8_2X8:
> >> + case MEDIA_BUS_FMT_YUYV8_2X8:
> >> + case MEDIA_BUS_FMT_YVYU8_2X8:
> >> + break;
> >> + default:
> >> + format->format.code = MEDIA_BUS_FMT_YUYV8_2X8;
> >
> > Is there any reason for not setting default format to MEDIA_BUS_FMT_UYVY8_2X8?
> >
>
>
> No good reason no, and I see that in max9286_enum_mbus_code(), we
> currently code to MEDIA_BUS_FMT_YUYV8_2X8, and that's the value that we
> init to, so that would be a better default indeed.
>

max9286_enum_mbus_code() returns MEDIA_BUS_FMT_UYVY8_2X8, no?

Thanks,
Mani

> I'll update this for v10.
>
>
> > Thanks,
> > Mani
> >
> >> + break;
> >> + }
> >> +
> >> + cfg_fmt = max9286_get_pad_format(priv, cfg, format->pad, format->which);
> >> + if (!cfg_fmt)
> >> + return -EINVAL;
> >> +
> >> + mutex_lock(&priv->mutex);
> >> + *cfg_fmt = format->format;
> >> + mutex_unlock(&priv->mutex);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int max9286_get_fmt(struct v4l2_subdev *sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_format *format)
> >> +{
> >> + struct max9286_priv *priv = sd_to_max9286(sd);
> >> + struct v4l2_mbus_framefmt *cfg_fmt;
> >> +
> >> + if (format->pad >= MAX9286_SRC_PAD)
> >> + return -EINVAL;
> >> +
> >> + cfg_fmt = max9286_get_pad_format(priv, cfg, format->pad, format->which);
> >> + if (!cfg_fmt)
> >> + return -EINVAL;
> >> +
> >> + mutex_lock(&priv->mutex);
> >> + format->format = *cfg_fmt;
> >> + mutex_unlock(&priv->mutex);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static const struct v4l2_subdev_video_ops max9286_video_ops = {
> >> + .s_stream = max9286_s_stream,
> >> +};
> >> +
> >> +static const struct v4l2_subdev_pad_ops max9286_pad_ops = {
> >> + .enum_mbus_code = max9286_enum_mbus_code,
> >> + .get_fmt = max9286_get_fmt,
> >> + .set_fmt = max9286_set_fmt,
> >> +};
> >> +
> >> +static const struct v4l2_subdev_ops max9286_subdev_ops = {
> >> + .video = &max9286_video_ops,
> >> + .pad = &max9286_pad_ops,
> >> +};
> >> +
> >> +static void max9286_init_format(struct v4l2_mbus_framefmt *fmt)
> >> +{
> >> + fmt->width = 1280;
> >> + fmt->height = 800;
> >> + fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
> >> + fmt->colorspace = V4L2_COLORSPACE_SRGB;
> >> + fmt->field = V4L2_FIELD_NONE;
> >> + fmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
> >> + fmt->quantization = V4L2_QUANTIZATION_DEFAULT;
> >> + fmt->xfer_func = V4L2_XFER_FUNC_DEFAULT;
> >> +}
> >> +
> >> +static int max9286_open(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
> >> +{
> >> + struct v4l2_mbus_framefmt *format;
> >> + unsigned int i;
> >> +
> >> + for (i = 0; i < MAX9286_N_SINKS; i++) {
> >> + format = v4l2_subdev_get_try_format(subdev, fh->pad, i);
> >> + max9286_init_format(format);
> >> + }
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static const struct v4l2_subdev_internal_ops max9286_subdev_internal_ops = {
> >> + .open = max9286_open,
> >> +};
> >> +
> >> +static int max9286_s_ctrl(struct v4l2_ctrl *ctrl)
> >> +{
> >> + switch (ctrl->id) {
> >> + case V4L2_CID_PIXEL_RATE:
> >> + return 0;
> >> + default:
> >> + return -EINVAL;
> >> + }
> >> +}
> >> +
> >> +static const struct v4l2_ctrl_ops max9286_ctrl_ops = {
> >> + .s_ctrl = max9286_s_ctrl,
> >> +};
> >> +
> >> +static int max9286_v4l2_register(struct max9286_priv *priv)
> >> +{
> >> + struct device *dev = &priv->client->dev;
> >> + struct fwnode_handle *ep;
> >> + int ret;
> >> + int i;
> >> +
> >> + /* Register v4l2 async notifiers for connected Camera subdevices */
> >> + ret = max9286_v4l2_notifier_register(priv);
> >> + if (ret) {
> >> + dev_err(dev, "Unable to register V4L2 async notifiers\n");
> >> + return ret;
> >> + }
> >> +
> >> + /* Configure V4L2 for the MAX9286 itself */
> >> +
> >> + for (i = 0; i < MAX9286_N_SINKS; i++)
> >> + max9286_init_format(&priv->fmt[i]);
> >> +
> >> + v4l2_i2c_subdev_init(&priv->sd, priv->client, &max9286_subdev_ops);
> >> + priv->sd.internal_ops = &max9286_subdev_internal_ops;
> >> + priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> >> +
> >> + v4l2_ctrl_handler_init(&priv->ctrls, 1);
> >> + priv->pixelrate = v4l2_ctrl_new_std(&priv->ctrls,
> >> + &max9286_ctrl_ops,
> >> + V4L2_CID_PIXEL_RATE,
> >> + 1, INT_MAX, 1, 50000000);
> >> +
> >> + priv->sd.ctrl_handler = &priv->ctrls;
> >> + ret = priv->ctrls.error;
> >> + if (ret)
> >> + goto err_async;
> >> +
> >> + priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> >> +
> >> + priv->pads[MAX9286_SRC_PAD].flags = MEDIA_PAD_FL_SOURCE;
> >> + for (i = 0; i < MAX9286_SRC_PAD; i++)
> >> + priv->pads[i].flags = MEDIA_PAD_FL_SINK;
> >> + ret = media_entity_pads_init(&priv->sd.entity, MAX9286_N_PADS,
> >> + priv->pads);
> >> + if (ret)
> >> + goto err_async;
> >> +
> >> + ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), MAX9286_SRC_PAD,
> >> + 0, 0);
> >> + if (!ep) {
> >> + dev_err(dev, "Unable to retrieve endpoint on \"port@4\"\n");
> >> + ret = -ENOENT;
> >> + goto err_async;
> >> + }
> >> + priv->sd.fwnode = ep;
> >> +
> >> + ret = v4l2_async_register_subdev(&priv->sd);
> >> + if (ret < 0) {
> >> + dev_err(dev, "Unable to register subdevice\n");
> >> + goto err_put_node;
> >> + }
> >> +
> >> + return 0;
> >> +
> >> +err_put_node:
> >> + fwnode_handle_put(ep);
> >> +err_async:
> >> + max9286_v4l2_notifier_unregister(priv);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static void max9286_v4l2_unregister(struct max9286_priv *priv)
> >> +{
> >> + fwnode_handle_put(priv->sd.fwnode);
> >> + v4l2_async_unregister_subdev(&priv->sd);
> >> + max9286_v4l2_notifier_unregister(priv);
> >> +}
> >> +
> >> +/* -----------------------------------------------------------------------------
> >> + * Probe/Remove
> >> + */
> >> +
> >> +static int max9286_setup(struct max9286_priv *priv)
> >> +{
> >> + /*
> >> + * Link ordering values for all enabled links combinations. Orders must
> >> + * be assigned sequentially from 0 to the number of enabled links
> >> + * without leaving any hole for disabled links. We thus assign orders to
> >> + * enabled links first, and use the remaining order values for disabled
> >> + * links are all links must have a different order value;
> >> + */
> >> + static const u8 link_order[] = {
> >> + (3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xxxx */
> >> + (3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xxx0 */
> >> + (3 << 6) | (2 << 4) | (0 << 2) | (1 << 0), /* xx0x */
> >> + (3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xx10 */
> >> + (3 << 6) | (0 << 4) | (2 << 2) | (1 << 0), /* x0xx */
> >> + (3 << 6) | (1 << 4) | (2 << 2) | (0 << 0), /* x1x0 */
> >> + (3 << 6) | (1 << 4) | (0 << 2) | (2 << 0), /* x10x */
> >> + (3 << 6) | (1 << 4) | (1 << 2) | (0 << 0), /* x210 */
> >> + (0 << 6) | (3 << 4) | (2 << 2) | (1 << 0), /* 0xxx */
> >> + (1 << 6) | (3 << 4) | (2 << 2) | (0 << 0), /* 1xx0 */
> >> + (1 << 6) | (3 << 4) | (0 << 2) | (2 << 0), /* 1x0x */
> >> + (2 << 6) | (3 << 4) | (1 << 2) | (0 << 0), /* 2x10 */
> >> + (1 << 6) | (0 << 4) | (3 << 2) | (2 << 0), /* 10xx */
> >> + (2 << 6) | (1 << 4) | (3 << 2) | (0 << 0), /* 21x0 */
> >> + (2 << 6) | (1 << 4) | (0 << 2) | (3 << 0), /* 210x */
> >> + (3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* 3210 */
> >> + };
> >> +
> >> + /*
> >> + * Set the I2C bus speed.
> >> + *
> >> + * Enable I2C Local Acknowledge during the probe sequences of the camera
> >> + * only. This should be disabled after the mux is initialised.
> >> + */
> >> + max9286_configure_i2c(priv, true);
> >> +
> >> + /*
> >> + * Reverse channel setup.
> >> + *
> >> + * - Enable custom reverse channel configuration (through register 0x3f)
> >> + * and set the first pulse length to 35 clock cycles.
> >> + * - Increase the reverse channel amplitude to 170mV to accommodate the
> >> + * high threshold enabled by the serializer driver.
> >> + */
> >> + max9286_write(priv, 0x3f, MAX9286_EN_REV_CFG | MAX9286_REV_FLEN(35));
> >> + max9286_write(priv, 0x3b, MAX9286_REV_TRF(1) | MAX9286_REV_AMP(70) |
> >> + MAX9286_REV_AMP_X);
> >> + usleep_range(2000, 2500);
> >> +
> >> + /*
> >> + * Enable GMSL links, mask unused ones and autodetect link
> >> + * used as CSI clock source.
> >> + */
> >> + max9286_write(priv, 0x00, MAX9286_MSTLINKSEL_AUTO | priv->route_mask);
> >> + max9286_write(priv, 0x0b, link_order[priv->route_mask]);
> >> + max9286_write(priv, 0x69, (0xf & ~priv->route_mask));
> >> +
> >> + /*
> >> + * Video format setup:
> >> + * Disable CSI output, VC is set according to Link number.
> >> + */
> >> + max9286_write(priv, 0x15, MAX9286_VCTYPE | MAX9286_0X15_RESV);
> >> +
> >> + /* Enable CSI-2 Lane D0-D3 only, DBL mode, YUV422 8-bit. */
> >> + max9286_write(priv, 0x12, MAX9286_CSIDBL | MAX9286_DBL |
> >> + MAX9286_CSILANECNT(priv->csi2_data_lanes) |
> >> + MAX9286_DATATYPE_YUV422_8BIT);
> >> +
> >> + /* Automatic: FRAMESYNC taken from the slowest Link. */
> >> + max9286_write(priv, 0x01, MAX9286_FSYNCMODE_INT_HIZ |
> >> + MAX9286_FSYNCMETH_AUTO);
> >> +
> >> + /* Enable HS/VS encoding, use D14/15 for HS/VS, invert VS. */
> >> + max9286_write(priv, 0x0c, MAX9286_HVEN | MAX9286_INVVS |
> >> + MAX9286_HVSRC_D14);
> >> +
> >> + /*
> >> + * The overlap window seems to provide additional validation by tracking
> >> + * the delay between vsync and frame sync, generating an error if the
> >> + * delay is bigger than the programmed window, though it's not yet clear
> >> + * what value should be set.
> >> + *
> >> + * As it's an optional value and can be disabled, we do so by setting
> >> + * a 0 overlap value.
> >> + */
> >> + max9286_write(priv, 0x63, 0);
> >> + max9286_write(priv, 0x64, 0);
> >> +
> >> + /*
> >> + * Wait for 2ms to allow the link to resynchronize after the
> >> + * configuration change.
> >> + */
> >> + usleep_range(2000, 5000);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static void max9286_gpio_set(struct gpio_chip *chip,
> >> + unsigned int offset, int value)
> >> +{
> >> + struct max9286_priv *priv = gpiochip_get_data(chip);
> >> +
> >> + if (value)
> >> + priv->gpio_state |= BIT(offset);
> >> + else
> >> + priv->gpio_state &= ~BIT(offset);
> >> +
> >> + max9286_write(priv, 0x0f, MAX9286_0X0F_RESERVED | priv->gpio_state);
> >> +}
> >> +
> >> +static int max9286_gpio_get(struct gpio_chip *chip, unsigned int offset)
> >> +{
> >> + struct max9286_priv *priv = gpiochip_get_data(chip);
> >> +
> >> + return priv->gpio_state & BIT(offset);
> >> +}
> >> +
> >> +static int max9286_register_gpio(struct max9286_priv *priv)
> >> +{
> >> + struct device *dev = &priv->client->dev;
> >> + struct gpio_chip *gpio = &priv->gpio;
> >> + int ret;
> >> +
> >> + static const char * const names[] = {
> >> + "GPIO0OUT",
> >> + "GPIO1OUT",
> >> + };
> >> +
> >> + /* Configure the GPIO */
> >> + gpio->label = dev_name(dev);
> >> + gpio->parent = dev;
> >> + gpio->owner = THIS_MODULE;
> >> + gpio->of_node = dev->of_node;
> >> + gpio->ngpio = 2;
> >> + gpio->base = -1;
> >> + gpio->set = max9286_gpio_set;
> >> + gpio->get = max9286_gpio_get;
> >> + gpio->can_sleep = true;
> >> + gpio->names = names;
> >> +
> >> + /* GPIO values default to high */
> >> + priv->gpio_state = BIT(0) | BIT(1);
> >> +
> >> + ret = devm_gpiochip_add_data(dev, gpio, priv);
> >> + if (ret)
> >> + dev_err(dev, "Unable to create gpio_chip\n");
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int max9286_init(struct device *dev)
> >> +{
> >> + struct max9286_priv *priv;
> >> + struct i2c_client *client;
> >> + int ret;
> >> +
> >> + client = to_i2c_client(dev);
> >> + priv = i2c_get_clientdata(client);
> >> +
> >> + /* Enable the bus power. */
> >> + ret = regulator_enable(priv->regulator);
> >> + if (ret < 0) {
> >> + dev_err(&client->dev, "Unable to turn PoC on\n");
> >> + return ret;
> >> + }
> >> +
> >> + ret = max9286_setup(priv);
> >> + if (ret) {
> >> + dev_err(dev, "Unable to setup max9286\n");
> >> + goto err_regulator;
> >> + }
> >> +
> >> + /*
> >> + * Register all V4L2 interactions for the MAX9286 and notifiers for
> >> + * any subdevices connected.
> >> + */
> >> + ret = max9286_v4l2_register(priv);
> >> + if (ret) {
> >> + dev_err(dev, "Failed to register with V4L2\n");
> >> + goto err_regulator;
> >> + }
> >> +
> >> + ret = max9286_i2c_mux_init(priv);
> >> + if (ret) {
> >> + dev_err(dev, "Unable to initialize I2C multiplexer\n");
> >> + goto err_v4l2_register;
> >> + }
> >> +
> >> + /* Leave the mux channels disabled until they are selected. */
> >> + max9286_i2c_mux_close(priv);
> >> +
> >> + return 0;
> >> +
> >> +err_v4l2_register:
> >> + max9286_v4l2_unregister(priv);
> >> +err_regulator:
> >> + regulator_disable(priv->regulator);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static void max9286_cleanup_dt(struct max9286_priv *priv)
> >> +{
> >> + struct max9286_source *source;
> >> +
> >> + for_each_source(priv, source) {
> >> + fwnode_handle_put(source->fwnode);
> >> + source->fwnode = NULL;
> >> + }
> >> +}
> >> +
> >> +static int max9286_parse_dt(struct max9286_priv *priv)
> >> +{
> >> + struct device *dev = &priv->client->dev;
> >> + struct device_node *i2c_mux;
> >> + struct device_node *node = NULL;
> >> + unsigned int i2c_mux_mask = 0;
> >> +
> >> + of_node_get(dev->of_node);
> >> + i2c_mux = of_find_node_by_name(dev->of_node, "i2c-mux");
> >> + if (!i2c_mux) {
> >> + dev_err(dev, "Failed to find i2c-mux node\n");
> >> + of_node_put(dev->of_node);
> >> + return -EINVAL;
> >> + }
> >> +
> >> + /* Identify which i2c-mux channels are enabled */
> >> + for_each_child_of_node(i2c_mux, node) {
> >> + u32 id = 0;
> >> +
> >> + of_property_read_u32(node, "reg", &id);
> >> + if (id >= MAX9286_NUM_GMSL)
> >> + continue;
> >> +
> >> + if (!of_device_is_available(node)) {
> >> + dev_dbg(dev, "Skipping disabled I2C bus port %u\n", id);
> >> + continue;
> >> + }
> >> +
> >> + i2c_mux_mask |= BIT(id);
> >> + }
> >> + of_node_put(node);
> >> + of_node_put(i2c_mux);
> >> +
> >> + /* Parse the endpoints */
> >> + for_each_endpoint_of_node(dev->of_node, node) {
> >> + struct max9286_source *source;
> >> + struct of_endpoint ep;
> >> +
> >> + of_graph_parse_endpoint(node, &ep);
> >> + dev_dbg(dev, "Endpoint %pOF on port %d",
> >> + ep.local_node, ep.port);
> >> +
> >> + if (ep.port > MAX9286_NUM_GMSL) {
> >> + dev_err(dev, "Invalid endpoint %s on port %d",
> >> + of_node_full_name(ep.local_node), ep.port);
> >> + continue;
> >> + }
> >> +
> >> + /* For the source endpoint just parse the bus configuration. */
> >> + if (ep.port == MAX9286_SRC_PAD) {
> >> + struct v4l2_fwnode_endpoint vep = {
> >> + .bus_type = V4L2_MBUS_CSI2_DPHY
> >> + };
> >> + int ret;
> >> +
> >> + ret = v4l2_fwnode_endpoint_parse(
> >> + of_fwnode_handle(node), &vep);
> >> + if (ret) {
> >> + of_node_put(node);
> >> + of_node_put(dev->of_node);
> >> + return ret;
> >> + }
> >> +
> >> + if (vep.bus_type != V4L2_MBUS_CSI2_DPHY) {
> >> + dev_err(dev,
> >> + "Media bus %u type not supported\n",
> >> + vep.bus_type);
> >> + v4l2_fwnode_endpoint_free(&vep);
> >> + of_node_put(node);
> >> + of_node_put(dev->of_node);
> >> + return -EINVAL;
> >> + }
> >> +
> >> + priv->csi2_data_lanes =
> >> + vep.bus.mipi_csi2.num_data_lanes;
> >> + v4l2_fwnode_endpoint_free(&vep);
> >> +
> >> + continue;
> >> + }
> >> +
> >> + /* Skip if the corresponding GMSL link is unavailable. */
> >> + if (!(i2c_mux_mask & BIT(ep.port)))
> >> + continue;
> >> +
> >> + if (priv->sources[ep.port].fwnode) {
> >> + dev_err(dev,
> >> + "Multiple port endpoints are not supported: %d",
> >> + ep.port);
> >> +
> >> + continue;
> >> + }
> >> +
> >> + source = &priv->sources[ep.port];
> >> + source->fwnode = fwnode_graph_get_remote_endpoint(
> >> + of_fwnode_handle(node));
> >> + if (!source->fwnode) {
> >> + dev_err(dev,
> >> + "Endpoint %pOF has no remote endpoint connection\n",
> >> + ep.local_node);
> >> +
> >> + continue;
> >> + }
> >> +
> >> + priv->source_mask |= BIT(ep.port);
> >> + priv->nsources++;
> >> + }
> >> + of_node_put(node);
> >> + of_node_put(dev->of_node);
> >> +
> >> + priv->route_mask = priv->source_mask;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int max9286_probe(struct i2c_client *client)
> >> +{
> >> + struct max9286_priv *priv;
> >> + int ret;
> >> +
> >> + priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
> >> + if (!priv)
> >> + return -ENOMEM;
> >> +
> >> + mutex_init(&priv->mutex);
> >> +
> >> + priv->client = client;
> >> + i2c_set_clientdata(client, priv);
> >> +
> >> + priv->gpiod_pwdn = devm_gpiod_get_optional(&client->dev, "enable",
> >> + GPIOD_OUT_HIGH);
> >> + if (IS_ERR(priv->gpiod_pwdn))
> >> + return PTR_ERR(priv->gpiod_pwdn);
> >> +
> >> + gpiod_set_consumer_name(priv->gpiod_pwdn, "max9286-pwdn");
> >> + gpiod_set_value_cansleep(priv->gpiod_pwdn, 1);
> >> +
> >> + /* Wait at least 4ms before the I2C lines latch to the address */
> >> + if (priv->gpiod_pwdn)
> >> + usleep_range(4000, 5000);
> >> +
> >> + /*
> >> + * The MAX9286 starts by default with all ports enabled, we disable all
> >> + * ports early to ensure that all channels are disabled if we error out
> >> + * and keep the bus consistent.
> >> + */
> >> + max9286_i2c_mux_close(priv);
> >> +
> >> + /*
> >> + * The MAX9286 initialises with auto-acknowledge enabled by default.
> >> + * This can be invasive to other transactions on the same bus, so
> >> + * disable it early. It will be enabled only as and when needed.
> >> + */
> >> + max9286_configure_i2c(priv, false);
> >> +
> >> + ret = max9286_register_gpio(priv);
> >> + if (ret)
> >> + goto err_powerdown;
> >> +
> >> + priv->regulator = devm_regulator_get(&client->dev, "poc");
> >> + if (IS_ERR(priv->regulator)) {
> >> + if (PTR_ERR(priv->regulator) != -EPROBE_DEFER)
> >> + dev_err(&client->dev,
> >> + "Unable to get PoC regulator (%ld)\n",
> >> + PTR_ERR(priv->regulator));
> >> + ret = PTR_ERR(priv->regulator);
> >> + goto err_powerdown;
> >> + }
> >> +
> >> + ret = max9286_parse_dt(priv);
> >> + if (ret)
> >> + goto err_powerdown;
> >> +
> >> + ret = max9286_init(&client->dev);
> >> + if (ret < 0)
> >> + goto err_cleanup_dt;
> >> +
> >> + return 0;
> >> +
> >> +err_cleanup_dt:
> >> + max9286_cleanup_dt(priv);
> >> +err_powerdown:
> >> + gpiod_set_value_cansleep(priv->gpiod_pwdn, 0);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int max9286_remove(struct i2c_client *client)
> >> +{
> >> + struct max9286_priv *priv = i2c_get_clientdata(client);
> >> +
> >> + i2c_mux_del_adapters(priv->mux);
> >> +
> >> + max9286_v4l2_unregister(priv);
> >> +
> >> + regulator_disable(priv->regulator);
> >> +
> >> + gpiod_set_value_cansleep(priv->gpiod_pwdn, 0);
> >> +
> >> + max9286_cleanup_dt(priv);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static const struct of_device_id max9286_dt_ids[] = {
> >> + { .compatible = "maxim,max9286" },
> >> + {},
> >> +};
> >> +MODULE_DEVICE_TABLE(of, max9286_dt_ids);
> >> +
> >> +static struct i2c_driver max9286_i2c_driver = {
> >> + .driver = {
> >> + .name = "max9286",
> >> + .of_match_table = of_match_ptr(max9286_dt_ids),
> >> + },
> >> + .probe_new = max9286_probe,
> >> + .remove = max9286_remove,
> >> +};
> >> +
> >> +module_i2c_driver(max9286_i2c_driver);
> >> +
> >> +MODULE_DESCRIPTION("Maxim MAX9286 GMSL Deserializer Driver");
> >> +MODULE_AUTHOR("Jacopo Mondi, Kieran Bingham, Laurent Pinchart, Niklas Söderlund, Vladimir Barinov");
> >> +MODULE_LICENSE("GPL");
> >> --
> >> 2.25.1
> >>
>