From cffc9fb1ed6c5cd0718b74d7759432e42f860087 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sat, 1 Jan 2022 19:28:00 +0100 Subject: [PATCH] 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 Reviewed-by: Jacopo Mondi Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/max9286.c | 84 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 75 insertions(+), 9 deletions(-) diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c index a65457b..bbf2006 100644 --- a/drivers/media/i2c/max9286.c +++ b/drivers/media/i2c/max9286.c @@ -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 | -- 2.7.4