Commit 74f81584 authored by Laurent Pinchart's avatar Laurent Pinchart Committed by Mauro Carvalho Chehab
Browse files

media: imx: imx7_mipi_csis: Calculate Ths_settle from source lane rate 



The Ths_settle timing parameter depends solely on the lane data rate of
the source. Calculate it at runtime instead of requiring it to be
specified in the device tree.

Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent bef63005

drivers/staging/media/imx/imx7-mipi-csis.c

+41 −7
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
#include <linux/reset.h>

#include <linux/spinlock.h>



#include <media/v4l2-common.h>

#include <media/v4l2-device.h>

#include <media/v4l2-fwnode.h>

#include <media/v4l2-mc.h>
@@ -482,6 +483,39 @@ static void __mipi_csis_set_format(struct csi_state *state) 
	mipi_csis_write(state, MIPI_CSIS_ISPRESOL_CH0, val);

}



static int mipi_csis_calculate_params(struct csi_state *state)

{

	s64 link_freq;

	u32 lane_rate;



	/* Calculate the line rate from the pixel rate. */

	link_freq = v4l2_get_link_freq(state->src_sd->ctrl_handler,

				       state->csis_fmt->width,

				       state->bus.num_data_lanes * 2);

	if (link_freq < 0) {

		dev_err(state->dev, "Unable to obtain link frequency: %d\n",

			(int)link_freq);

		return link_freq;

	}



	lane_rate = link_freq * 2;



	if (lane_rate < 80000000 || lane_rate > 1500000000) {

		dev_dbg(state->dev, "Out-of-bound lane rate %u\n", lane_rate);

		return -EINVAL;

	}



	/*

	 * The HSSETTLE counter value is document in a table, but can also

	 * easily be calculated.

	 */

	state->hs_settle = (lane_rate - 5000000) / 45000000;

	dev_dbg(state->dev, "lane rate %u, Ths_settle %u\n",

		lane_rate, state->hs_settle);



	return 0;

}



static void mipi_csis_set_params(struct csi_state *state)

{

	int lanes = state->bus.num_data_lanes;
@@ -608,9 +642,13 @@ static void mipi_csis_log_counters(struct csi_state *state, bool non_errors) 
static int mipi_csis_s_stream(struct v4l2_subdev *mipi_sd, int enable)

{

	struct csi_state *state = mipi_sd_to_csis_state(mipi_sd);

	int ret = 0;

	int ret;



	if (enable) {

		ret = mipi_csis_calculate_params(state);

		if (ret < 0)

			return ret;



		mipi_csis_clear_counters(state);

		ret = pm_runtime_get_sync(&state->pdev->dev);

		if (ret < 0) {
@@ -943,9 +981,6 @@ static int mipi_csis_parse_dt(struct platform_device *pdev, 
	if (IS_ERR(state->mrst))

		return PTR_ERR(state->mrst);



	/* Get MIPI CSI-2 bus configuration from the endpoint node. */

	of_property_read_u32(node, "fsl,csis-hs-settle", &state->hs_settle);



	return 0;

}
@@ -1143,9 +1178,8 @@ static int mipi_csis_probe(struct platform_device *pdev) 
			goto unregister_all;

	}



	dev_info(&pdev->dev, "lanes: %d, hs_settle: %d, freq: %u\n",

		 state->bus.num_data_lanes, state->hs_settle,

		 state->clk_frequency);

	dev_info(&pdev->dev, "lanes: %d, freq: %u\n",

		 state->bus.num_data_lanes, state->clk_frequency);



	return 0;