media: imx-jpeg: Support to assign slot for encoder/decoder

imx jpeg encoder and decoder support 4 slots each,
aim to support some virtualization scenarios.

driver should only enable one slot one time.

but due to some hardware issue,
only slot 0 can be enabled in imx8q platform,
and they may be fixed in imx9 platform.
Signed-off-by: Ming Qian <ming.qian@nxp.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/nxp/imx-jpeg/mxc-jpeg-hw.h

@@ -58,7 +58,6 @@
 #define CAST_OFBSIZE_LO			CAST_STATUS18
 #define CAST_OFBSIZE_HI			CAST_STATUS19
 
-#define MXC_MAX_SLOTS	1 /* TODO use all 4 slots*/
 /* JPEG-Decoder Wrapper Slot Registers 0..3 */
 #define SLOT_BASE			0x10000
 #define SLOT_STATUS			0x0

drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.h

@@ -97,7 +97,7 @@ struct mxc_jpeg_ctx {
 	struct mxc_jpeg_q_data		cap_q;
 	struct v4l2_fh			fh;
 	enum mxc_jpeg_enc_state		enc_state;
-	unsigned int			slot;
+	int				slot;
 	unsigned int			source_change;
 	bool				header_parsed;
 	struct v4l2_ctrl_handler	ctrl_handler;
@@ -106,6 +106,7 @@ struct mxc_jpeg_ctx {
 };
 
 struct mxc_jpeg_slot_data {
+	int slot;
 	bool used;
 	struct mxc_jpeg_desc *desc; // enc/dec descriptor
 	struct mxc_jpeg_desc *cfg_desc; // configuration descriptor
@@ -128,7 +129,7 @@ struct mxc_jpeg_dev {
 	struct v4l2_device		v4l2_dev;
 	struct v4l2_m2m_dev		*m2m_dev;
 	struct video_device		*dec_vdev;
-	struct mxc_jpeg_slot_data	slot_data[MXC_MAX_SLOTS];
+	struct mxc_jpeg_slot_data	slot_data;
 	int				num_domains;
 	struct device			**pd_dev;
 	struct device_link		**pd_link;