media: i2c: max9286: Support manual framesync operation

The MAX9286 can generate a framesync signal to synchronize the cameras,
using an internal timer. Support this mode of operation and configure it
through the .s_frameinterval() operation. If the frame interval is not
0, framesync is switched to manual mode with the specified interval,
otherwise automatic mode is used.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
This commit is contained in:
Laurent Pinchart 2022-01-01 19:28:00 +01:00 committed by Mauro Carvalho Chehab
parent 817660f44d
commit cffc9fb1ed

View file

@ -174,9 +174,11 @@ struct max9286_priv {
u32 gpio_poc[2];
struct v4l2_ctrl_handler ctrls;
struct v4l2_ctrl *pixelrate;
struct v4l2_ctrl *pixelrate_ctrl;
unsigned int pixelrate;
struct v4l2_mbus_framefmt fmt[MAX9286_N_SINKS];
struct v4l2_fract interval;
/* Protects controls and fmt structures */
struct mutex mutex;
@ -477,6 +479,40 @@ static int max9286_check_config_link(struct max9286_priv *priv,
return 0;
}
static void max9286_set_fsync_period(struct max9286_priv *priv)
{
u32 fsync;
if (!priv->interval.numerator || !priv->interval.denominator) {
/*
* Special case, a null interval enables automatic FRAMESYNC
* mode. FRAMESYNC is taken from the slowest link.
*/
max9286_write(priv, 0x01, MAX9286_FSYNCMODE_INT_HIZ |
MAX9286_FSYNCMETH_AUTO);
return;
}
/*
* Manual FRAMESYNC
*
* The FRAMESYNC generator is configured with a period expressed as a
* number of PCLK periods.
*/
fsync = div_u64((u64)priv->pixelrate * priv->interval.numerator,
priv->interval.denominator);
dev_dbg(&priv->client->dev, "fsync period %u (pclk %u)\n", fsync,
priv->pixelrate);
max9286_write(priv, 0x01, MAX9286_FSYNCMODE_INT_OUT |
MAX9286_FSYNCMETH_MANUAL);
max9286_write(priv, 0x06, (fsync >> 0) & 0xff);
max9286_write(priv, 0x07, (fsync >> 8) & 0xff);
max9286_write(priv, 0x08, (fsync >> 16) & 0xff);
}
/* -----------------------------------------------------------------------------
* V4L2 Subdev
*/
@ -515,11 +551,13 @@ static int max9286_set_pixelrate(struct max9286_priv *priv)
return -EINVAL;
}
priv->pixelrate = pixelrate;
/*
* 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,
return v4l2_ctrl_s_ctrl_int64(priv->pixelrate_ctrl,
pixelrate * priv->nsources);
}
@ -659,6 +697,8 @@ static int max9286_s_stream(struct v4l2_subdev *sd, int enable)
int ret;
if (enable) {
max9286_set_fsync_period(priv);
/*
* The frame sync between cameras is transmitted across the
* reverse channel as GPIO. We must open all channels while
@ -718,6 +758,32 @@ static int max9286_s_stream(struct v4l2_subdev *sd, int enable)
return 0;
}
static int max9286_g_frame_interval(struct v4l2_subdev *sd,
struct v4l2_subdev_frame_interval *interval)
{
struct max9286_priv *priv = sd_to_max9286(sd);
if (interval->pad != MAX9286_SRC_PAD)
return -EINVAL;
interval->interval = priv->interval;
return 0;
}
static int max9286_s_frame_interval(struct v4l2_subdev *sd,
struct v4l2_subdev_frame_interval *interval)
{
struct max9286_priv *priv = sd_to_max9286(sd);
if (interval->pad != MAX9286_SRC_PAD)
return -EINVAL;
priv->interval = interval->interval;
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)
@ -809,6 +875,8 @@ static int max9286_get_fmt(struct v4l2_subdev *sd,
static const struct v4l2_subdev_video_ops max9286_video_ops = {
.s_stream = max9286_s_stream,
.g_frame_interval = max9286_g_frame_interval,
.s_frame_interval = max9286_s_frame_interval,
};
static const struct v4l2_subdev_pad_ops max9286_pad_ops = {
@ -893,10 +961,10 @@ static int max9286_v4l2_register(struct max9286_priv *priv)
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->pixelrate_ctrl = 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;
@ -1006,9 +1074,7 @@ static int max9286_setup(struct max9286_priv *priv)
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);
max9286_set_fsync_period(priv);
/* Enable HS/VS encoding, use D14/15 for HS/VS, invert VS. */
max9286_write(priv, 0x0c, MAX9286_HVEN | MAX9286_INVVS |