Commit f3d5f661 authored by Laurent Pinchart's avatar Laurent Pinchart Committed by Greg Kroah-Hartman
Browse files

greybus: camera: Clean up on stream configuration failure 



When the camera pipeline can't be configured due to a failure of one of
the components (failure to start the CSI transmitter for instance),
components that have already been setup for video streaming need to be
set back to a quiescient state. This is especially important to ensure
that a stream configuration failure won't keep the UniPro links in high
speed mode forever.

Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: default avatarGjorgji Rosikopulos <grosikopulos@mm-sol.com>
Tested-by: default avatarGjorgji Rosikopulos <grosikopulos@mm-sol.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@google.com>
parent d1a8c36e

drivers/staging/greybus/camera.c

+91 −50
Original line number Diff line number Diff line
@@ -115,7 +115,7 @@ static const struct gb_camera_fmt_map mbus_to_gbus_format[] = { 
#define gcam_err(gcam, format...)	dev_err(&gcam->bundle->dev, format)



/* -----------------------------------------------------------------------------

 * Camera Protocol Operations

 * Hardware Configuration

 */



static int gb_camera_set_intf_power_mode(struct gb_camera *gcam, u8 intf_id,
@@ -173,6 +173,87 @@ static int gb_camera_set_power_mode(struct gb_camera *gcam, bool hs) 
	return 0;

}



struct ap_csi_config_request {

	__u8 csi_id;

	__u8 flags;

#define GB_CAMERA_CSI_FLAG_CLOCK_CONTINUOUS 0x01

	__u8 num_lanes;

	__u8 padding;

	__le32 bus_freq;

	__le32 lines_per_second;

} __packed;



static int gb_camera_setup_data_connection(struct gb_camera *gcam,

		const struct gb_camera_configure_streams_response *resp,

		struct gb_camera_csi_params *csi_params)

{

	struct ap_csi_config_request csi_cfg;

	int ret;



	/* Set the UniPro link to high speed mode. */

	ret = gb_camera_set_power_mode(gcam, true);

	if (ret < 0)

		return ret;



	/*

	 * Configure the APB1 CSI transmitter using the lines count reported by

	 * the  camera module, but with hard-coded bus frequency and lanes number.

	 *

	 * TODO: use the clocking and size informations reported by camera module

	 * to compute the required CSI bandwidth, and configure the CSI receiver

	 * on AP side, and the CSI transmitter on APB1 side accordingly.

	 */

	memset(&csi_cfg, 0, sizeof(csi_cfg));

	csi_cfg.csi_id = 1;

	csi_cfg.flags = 0;

	csi_cfg.num_lanes = resp->num_lanes;

	csi_cfg.bus_freq = cpu_to_le32(960000000);

	csi_cfg.lines_per_second = resp->lines_per_second;



	ret = gb_hd_output(gcam->connection->hd, &csi_cfg,

			   sizeof(csi_cfg),

			   GB_APB_REQUEST_CSI_TX_CONTROL, false);



	if (ret < 0) {

		gcam_err(gcam, "failed to start the CSI transmitter\n");

		gb_camera_set_power_mode(gcam, false);

		return ret;

	}



	if (csi_params) {

		csi_params->num_lanes = csi_cfg.num_lanes;

		/* Transmitting two bits per cycle. (DDR clock) */

		csi_params->clk_freq = csi_cfg.bus_freq / 2;

		csi_params->lines_per_second = csi_cfg.lines_per_second;

	}



	return 0;

}



static void gb_camera_teardown_data_connection(struct gb_camera *gcam)

{

	struct ap_csi_config_request csi_cfg;

	int ret;



	/* Stop the APB1 CSI transmitter. */

	memset(&csi_cfg, 0, sizeof(csi_cfg));

	csi_cfg.csi_id = 1;



	ret = gb_hd_output(gcam->connection->hd, &csi_cfg,

			   sizeof(csi_cfg),

			   GB_APB_REQUEST_CSI_TX_CONTROL, false);



	if (ret < 0)

		gcam_err(gcam, "failed to stop the CSI transmitter\n");



	/* Set the UniPro link to low speed mode. */

	gb_camera_set_power_mode(gcam, false);

}



/* -----------------------------------------------------------------------------

 * Camera Protocol Operations

 */



static int gb_camera_capabilities(struct gb_camera *gcam,

				  u8 *capabilities, size_t *size)

{
@@ -211,16 +292,6 @@ done: 
	return ret;

}



struct ap_csi_config_request {

	__u8 csi_id;

	__u8 flags;

#define GB_CAMERA_CSI_FLAG_CLOCK_CONTINUOUS 0x01

	__u8 num_lanes;

	__u8 padding;

	__le32 bus_freq;

	__le32 lines_per_second;

} __packed;



static int gb_camera_configure_streams(struct gb_camera *gcam,

				       unsigned int *num_streams,

				       unsigned int *flags,
@@ -229,7 +300,6 @@ static int gb_camera_configure_streams(struct gb_camera *gcam, 
{

	struct gb_camera_configure_streams_request *req;

	struct gb_camera_configure_streams_response *resp;

	struct ap_csi_config_request csi_cfg;



	unsigned int nstreams = *num_streams;

	unsigned int i;
@@ -315,50 +385,21 @@ static int gb_camera_configure_streams(struct gb_camera *gcam, 
		goto done;

	}



	/* Setup unipro link speed. */

	ret = gb_camera_set_power_mode(gcam, nstreams != 0);

	if (ret < 0)

	if (resp->num_streams) {

		ret = gb_camera_setup_data_connection(gcam, resp, csi_params);

		if (ret < 0) {

			memset(req, 0, sizeof(*req));

			gb_operation_sync(gcam->connection,

					  GB_CAMERA_TYPE_CONFIGURE_STREAMS,

					  req, req_size, resp, resp_size);

			goto done;



	/*

	 * Configure the APB1 CSI transmitter using the lines count reported by

	 * the  camera module, but with hard-coded bus frequency and lanes number.

	 *

	 * TODO: use the clocking and size informations reported by camera module

	 * to compute the required CSI bandwidth, and configure the CSI receiver

	 * on AP side, and the CSI transmitter on APB1 side accordingly.

	 */

	memset(&csi_cfg, 0, sizeof(csi_cfg));



	if (nstreams) {

		csi_cfg.csi_id = 1;

		csi_cfg.flags = 0;

		csi_cfg.num_lanes = resp->num_lanes;

		csi_cfg.bus_freq = cpu_to_le32(960000000);

		csi_cfg.lines_per_second = resp->lines_per_second;

		ret = gb_hd_output(gcam->connection->hd, &csi_cfg,

				   sizeof(csi_cfg),

				   GB_APB_REQUEST_CSI_TX_CONTROL, false);

		if (csi_params) {

			csi_params->num_lanes = csi_cfg.num_lanes;

			/* Transmitting two bits per cycle. (DDR clock) */

			csi_params->clk_freq = csi_cfg.bus_freq / 2;

			csi_params->lines_per_second = csi_cfg.lines_per_second;

		}

	} else {

		csi_cfg.csi_id = 1;

		ret = gb_hd_output(gcam->connection->hd, &csi_cfg,

				   sizeof(csi_cfg),

				   GB_APB_REQUEST_CSI_TX_CONTROL, false);

		gb_camera_teardown_data_connection(gcam);

	}



	if (ret < 0)

		gcam_err(gcam, "failed to %s the CSI transmitter\n",

			 nstreams ? "start" : "stop");



	*flags = resp->flags;

	*num_streams = resp->num_streams;

	ret = 0;



done:

	mutex_unlock(&gcam->mutex);

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