blob: eb2b8e42335bdfa280a83a1d6ec7adf49abb8cc6 [file] [log] [blame]
// 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)
#define MAX9286_REV_AMP_HIGH 170
/* 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_subdev *sd;
struct fwnode_handle *fwnode;
};
struct max9286_asd {
struct v4l2_async_subdev base;
struct max9286_source *source;
};
static inline struct max9286_asd *to_max9286_asd(struct v4l2_async_subdev *asd)
{
return container_of(asd, struct max9286_asd, base);
}
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;
/* The initial reverse control channel amplitude. */
u32 init_rev_chan_mv;
u32 rev_chan_mv;
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 struct max9286_source *next_source(struct max9286_priv *priv,
struct max9286_source *source)
{
if (!source)
source = &priv->sources[0];
else
source++;
for (; source < &priv->sources[MAX9286_NUM_GMSL]; source++) {
if (source->fwnode)
return source;
}
return NULL;
}
#define for_each_source(priv, source) \
for ((source) = NULL; ((source) = next_source((priv), (source))); )
#define to_index(priv, source) ((source) - &(priv)->sources[0])
static inline struct max9286_priv *sd_to_max9286(struct v4l2_subdev *sd)
{
return container_of(sd, struct max9286_priv, sd);
}
/* -----------------------------------------------------------------------------
* I2C IO
*/
static int max9286_read(struct max9286_priv *priv, u8 reg)
{
int ret;
ret = i2c_smbus_read_byte_data(priv->client, reg);
if (ret < 0)
dev_err(&priv->client->dev,
"%s: register 0x%02x read failed (%d)\n",
__func__, reg, ret);
return ret;
}
static int max9286_write(struct max9286_priv *priv, u8 reg, u8 val)
{
int ret;
ret = i2c_smbus_write_byte_data(priv->client, reg, val);
if (ret < 0)
dev_err(&priv->client->dev,
"%s: register 0x%02x write failed (%d)\n",
__func__, reg, ret);
return ret;
}
/* -----------------------------------------------------------------------------
* I2C Multiplexer
*/
static void max9286_i2c_mux_configure(struct max9286_priv *priv, u8 conf)
{
max9286_write(priv, 0x0a, conf);
/*
* We must sleep after any change to the forward or reverse channel
* configuration.
*/
usleep_range(3000, 5000);
}
static void max9286_i2c_mux_open(struct max9286_priv *priv)
{
/* Open all channels on the MAX9286 */
max9286_i2c_mux_configure(priv, 0xff);
priv->mux_open = true;
}
static void max9286_i2c_mux_close(struct max9286_priv *priv)
{
/*
* Ensure that both the forward and reverse channel are disabled on the
* mux, and that the channel ID is invalidated to ensure we reconfigure
* on the next max9286_i2c_mux_select() call.
*/
max9286_i2c_mux_configure(priv, 0x00);
priv->mux_open = false;
priv->mux_channel = -1;
}
static int max9286_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
{
struct max9286_priv *priv = i2c_mux_priv(muxc);
/* Channel select is disabled when configured in the opened state. */
if (priv->mux_open)
return 0;
if (priv->mux_channel == chan)
return 0;
priv->mux_channel = chan;
max9286_i2c_mux_configure(priv, MAX9286_FWDCCEN(chan) |
MAX9286_REVCCEN(chan));
return 0;
}
static int max9286_i2c_mux_init(struct max9286_priv *priv)
{
struct max9286_source *source;
int ret;
if (!i2c_check_functionality(priv->client->adapter,
I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
return -ENODEV;
priv->mux = i2c_mux_alloc(priv->client->adapter, &priv->client->dev,
priv->nsources, 0, I2C_MUX_LOCKED,
max9286_i2c_mux_select, NULL);
if (!priv->mux)
return -ENOMEM;
priv->mux->priv = priv;
for_each_source(priv, source) {
unsigned int index = to_index(priv, source);
ret = i2c_mux_add_adapter(priv->mux, 0, index, 0);
if (ret < 0)
goto error;
}
return 0;
error:
i2c_mux_del_adapters(priv->mux);
return ret;
}
static void max9286_configure_i2c(struct max9286_priv *priv, bool localack)
{
u8 config = MAX9286_I2CSLVSH_469NS_234NS | MAX9286_I2CSLVTO_1024US |
MAX9286_I2CMSTBT_105KBPS;
if (localack)
config |= MAX9286_I2CLOCACK;
max9286_write(priv, 0x34, config);
usleep_range(3000, 5000);
}
static void max9286_reverse_channel_setup(struct max9286_priv *priv,
unsigned int chan_amplitude)
{
u8 chan_config;
if (priv->rev_chan_mv == chan_amplitude)
return;
priv->rev_chan_mv = chan_amplitude;
/* Reverse channel transmission time: default to 1. */
chan_config = MAX9286_REV_TRF(1);
/*
* Reverse channel setup.
*
* - Enable custom reverse channel configuration (through register 0x3f)
* and set the first pulse length to 35 clock cycles.
* - Adjust reverse channel amplitude: values > 130 are programmed
* using the additional +100mV REV_AMP_X boost flag
*/
max9286_write(priv, 0x3f, MAX9286_EN_REV_CFG | MAX9286_REV_FLEN(35));
if (chan_amplitude > 100) {
/* It is not possible to express values (100 < x < 130) */
chan_amplitude = max(30U, chan_amplitude - 100);
chan_config |= MAX9286_REV_AMP_X;
}
max9286_write(priv, 0x3b, chan_config | MAX9286_REV_AMP(chan_amplitude));
usleep_range(2000, 2500);
}
/*
* max9286_check_video_links() - Make sure video links are detected and locked
*
* Performs safety checks on video link status. Make sure they are detected
* and all enabled links are locked.
*
* Returns 0 for success, -EIO for errors.
*/
static int max9286_check_video_links(struct max9286_priv *priv)
{
unsigned int i;
int ret;
/*
* Make sure valid video links are detected.
* The delay is not characterized in de-serializer manual, wait up
* to 5 ms.
*/
for (i = 0; i < 10; i++) {
ret = max9286_read(priv, 0x49);
if (ret < 0)
return -EIO;
if ((ret & MAX9286_VIDEO_DETECT_MASK) == priv->source_mask)
break;
usleep_range(350, 500);
}
if (i == 10) {
dev_err(&priv->client->dev,
"Unable to detect video links: 0x%02x\n", ret);
return -EIO;
}
/* Make sure all enabled links are locked (4ms max). */
for (i = 0; i < 10; i++) {
ret = max9286_read(priv, 0x27);
if (ret < 0)
return -EIO;
if (ret & MAX9286_LOCKED)
break;
usleep_range(350, 450);
}
if (i == 10) {
dev_err(&priv->client->dev, "Not all enabled links locked\n");
return -EIO;
}
return 0;
}
/*
* max9286_check_config_link() - Detect and wait for configuration links
*
* Determine if the configuration channel is up and settled for a link.
*
* Returns 0 for success, -EIO for errors.
*/
static int max9286_check_config_link(struct max9286_priv *priv,
unsigned int source_mask)
{
unsigned int conflink_mask = (source_mask & 0x0f) << 4;
unsigned int i;
int ret;
/*
* Make sure requested configuration links are detected.
* The delay is not characterized in the chip manual: wait up
* to 5 milliseconds.
*/
for (i = 0; i < 10; i++) {
ret = max9286_read(priv, 0x49);
if (ret < 0)
return -EIO;
ret &= 0xf0;
if (ret == conflink_mask)
break;
usleep_range(350, 500);
}
if (ret != conflink_mask) {
dev_err(&priv->client->dev,
"Unable to detect configuration links: 0x%02x expected 0x%02x\n",
ret, conflink_mask);
return -EIO;
}
dev_info(&priv->client->dev,
"Successfully detected configuration links after %u loops: 0x%02x\n",
i, conflink_mask);
return 0;
}
/* -----------------------------------------------------------------------------
* V4L2 Subdev
*/
static int max9286_set_pixelrate(struct max9286_priv *priv)
{
struct max9286_source *source = NULL;
u64 pixelrate = 0;
for_each_source(priv, source) {
struct v4l2_ctrl *ctrl;
u64 source_rate = 0;
/* Pixel rate is mandatory to be reported by sources. */
ctrl = v4l2_ctrl_find(source->sd->ctrl_handler,
V4L2_CID_PIXEL_RATE);
if (!ctrl) {
pixelrate = 0;
break;
}
/* All source must report the same pixel rate. */
source_rate = v4l2_ctrl_g_ctrl_int64(ctrl);
if (!pixelrate) {
pixelrate = source_rate;
} else if (pixelrate != source_rate) {
dev_err(&priv->client->dev,
"Unable to calculate pixel rate\n");
return -EINVAL;
}
}
if (!pixelrate) {
dev_err(&priv->client->dev,
"No pixel rate control available in sources\n");
return -EINVAL;
}
/*
* The CSI-2 transmitter pixel rate is the single source rate multiplied
* by the number of available sources.
*/
return v4l2_ctrl_s_ctrl_int64(priv->pixelrate,
pixelrate * priv->nsources);
}
static int max9286_notify_bound(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd)
{
struct max9286_priv *priv = sd_to_max9286(notifier->sd);
struct max9286_source *source = to_max9286_asd(asd)->source;
unsigned int index = to_index(priv, source);
unsigned int src_pad;
int ret;
ret = media_entity_get_fwnode_pad(&subdev->entity,
source->fwnode,
MEDIA_PAD_FL_SOURCE);
if (ret < 0) {
dev_err(&priv->client->dev,
"Failed to find pad for %s\n", subdev->name);
return ret;
}
priv->bound_sources |= BIT(index);
source->sd = subdev;
src_pad = ret;
ret = media_create_pad_link(&source->sd->entity, src_pad,
&priv->sd.entity, index,
MEDIA_LNK_FL_ENABLED |
MEDIA_LNK_FL_IMMUTABLE);
if (ret) {
dev_err(&priv->client->dev,
"Unable to link %s:%u -> %s:%u\n",
source->sd->name, src_pad, priv->sd.name, index);
return ret;
}
dev_dbg(&priv->client->dev, "Bound %s pad: %u on index %u\n",
subdev->name, src_pad, index);
/*
* As we register a subdev notifiers we won't get a .complete() callback
* here, so we have to use bound_sources to identify when all remote
* serializers have probed.
*/
if (priv->bound_sources != priv->source_mask)
return 0;
/*
* All enabled sources have probed and enabled their reverse control
* channels:
*
* - Increase the reverse channel amplitude to compensate for the
* remote ends high threshold
* - Verify all configuration links are properly detected
* - Disable auto-ack as communication on the control channel are now
* stable.
*/
max9286_reverse_channel_setup(priv, MAX9286_REV_AMP_HIGH);
max9286_check_config_link(priv, priv->source_mask);
max9286_configure_i2c(priv, false);
return max9286_set_pixelrate(priv);
}
static void max9286_notify_unbind(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd)
{
struct max9286_priv *priv = sd_to_max9286(notifier->sd);
struct max9286_source *source = to_max9286_asd(asd)->source;
unsigned int index = to_index(priv, source);
source->sd = NULL;
priv->bound_sources &= ~BIT(index);
}
static const struct v4l2_async_notifier_operations max9286_notify_ops = {
.bound = max9286_notify_bound,
.unbind = max9286_notify_unbind,
};
static int max9286_v4l2_notifier_register(struct max9286_priv *priv)
{
struct device *dev = &priv->client->dev;
struct max9286_source *source = NULL;
int ret;
if (!priv->nsources)
return 0;
v4l2_async_nf_init(&priv->notifier);
for_each_source(priv, source) {
unsigned int i = to_index(priv, source);
struct max9286_asd *mas;
mas = v4l2_async_nf_add_fwnode(&priv->notifier, source->fwnode,
struct max9286_asd);
if (IS_ERR(mas)) {
dev_err(dev, "Failed to add subdev for source %u: %ld",
i, PTR_ERR(mas));
v4l2_async_nf_cleanup(&priv->notifier);
return PTR_ERR(mas);
}
mas->source = source;
}
priv->notifier.ops = &max9286_notify_ops;
ret = v4l2_async_subdev_nf_register(&priv->sd, &priv->notifier);
if (ret) {
dev_err(dev, "Failed to register subdev_notifier");
v4l2_async_nf_cleanup(&priv->notifier);
return ret;
}
return 0;
}
static void max9286_v4l2_notifier_unregister(struct max9286_priv *priv)
{
if (!priv->nsources)
return;
v4l2_async_nf_unregister(&priv->notifier);
v4l2_async_nf_cleanup(&priv->notifier);
}
static int max9286_s_stream(struct v4l2_subdev *sd, int enable)
{
struct max9286_priv *priv = sd_to_max9286(sd);
struct max9286_source *source;
unsigned int i;
bool sync = false;
int ret;
if (enable) {
/*
* The frame sync between cameras is transmitted across the
* reverse channel as GPIO. We must open all channels while
* streaming to allow this synchronisation signal to be shared.
*/
max9286_i2c_mux_open(priv);
/* Start all cameras. */
for_each_source(priv, source) {
ret = v4l2_subdev_call(source->sd, video, s_stream, 1);
if (ret)
return ret;
}
ret = max9286_check_video_links(priv);
if (ret)
return ret;
/*
* Wait until frame synchronization is locked.
*
* Manual says frame sync locking should take ~6 VTS.
* From practical experience at least 8 are required. Give
* 12 complete frames time (~400ms at 30 fps) to achieve frame
* locking before returning error.
*/
for (i = 0; i < 40; i++) {
if (max9286_read(priv, 0x31) & MAX9286_FSYNC_LOCKED) {
sync = true;
break;
}
usleep_range(9000, 11000);
}
if (!sync) {
dev_err(&priv->client->dev,
"Failed to get frame synchronization\n");
return -EXDEV; /* Invalid cross-device link */
}
/*
* Enable CSI output, VC set according to link number.
* Bit 7 must be set (chip manual says it's 0 and reserved).
*/
max9286_write(priv, 0x15, 0x80 | MAX9286_VCTYPE |
MAX9286_CSIOUTEN | MAX9286_0X15_RESV);
} else {
max9286_write(priv, 0x15, MAX9286_VCTYPE | MAX9286_0X15_RESV);
/* Stop all cameras. */
for_each_source(priv, source)
v4l2_subdev_call(source->sd, video, s_stream, 0);
max9286_i2c_mux_close(priv);
}
return 0;
}
static int max9286_enum_mbus_code(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_mbus_code_enum *code)
{
if (code->pad || code->index > 0)
return -EINVAL;
code->code = MEDIA_BUS_FMT_UYVY8_1X16;
return 0;
}
static struct v4l2_mbus_framefmt *
max9286_get_pad_format(struct max9286_priv *priv,
struct v4l2_subdev_state *sd_state,
unsigned int pad, u32 which)
{
switch (which) {
case V4L2_SUBDEV_FORMAT_TRY:
return v4l2_subdev_get_try_format(&priv->sd, sd_state, 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_state *sd_state,
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_1X16:
case MEDIA_BUS_FMT_VYUY8_1X16:
case MEDIA_BUS_FMT_YUYV8_1X16:
case MEDIA_BUS_FMT_YVYU8_1X16:
break;
default:
format->format.code = MEDIA_BUS_FMT_UYVY8_1X16;
break;
}
cfg_fmt = max9286_get_pad_format(priv, sd_state, 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_state *sd_state,
struct v4l2_subdev_format *format)
{
struct max9286_priv *priv = sd_to_max9286(sd);
struct v4l2_mbus_framefmt *cfg_fmt;
unsigned int pad = format->pad;
/*
* Multiplexed Stream Support: Support link validation by returning the
* format of the first bound link. All links must have the same format,
* as we do not support mixing and matching of cameras connected to the
* max9286.
*/
if (pad == MAX9286_SRC_PAD)
pad = __ffs(priv->bound_sources);
cfg_fmt = max9286_get_pad_format(priv, sd_state, 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_1X16;
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->state, 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);
max9286_reverse_channel_setup(priv, priv->init_rev_chan_mv);
/*
* 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;
/* Configure the GPIO */
gpio->label = dev_name(dev);
gpio->parent = dev;
gpio->owner = THIS_MODULE;
gpio->ngpio = 2;
gpio->base = -1;
gpio->set = max9286_gpio_set;
gpio->get = max9286_gpio_get;
gpio->can_sleep = true;
/* 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;
u32 reverse_channel_microvolt;
/* Balance the of_node_put() performed by of_find_node_by_name(). */
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");
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);
return ret;
}
priv->csi2_data_lanes =
vep.bus.mipi_csi2.num_data_lanes;
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);
/*
* Parse the initial value of the reverse channel amplitude from
* the firmware interface and convert it to millivolts.
*
* Default it to 170mV for backward compatibility with DTBs that do not
* provide the property.
*/
if (of_property_read_u32(dev->of_node,
"maxim,reverse-channel-microvolt",
&reverse_channel_microvolt))
priv->init_rev_chan_mv = 170;
else
priv->init_rev_chan_mv = reverse_channel_microvolt / 1000U;
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)) {
ret = PTR_ERR(priv->regulator);
dev_err_probe(&client->dev, ret,
"Unable to get PoC regulator\n");
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");