--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TI CSI2RX Shim Wrapper Driver
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
+ *
+ * Author: Pratyush Yadav <p.yadav@ti.com>
+ * Author: Jai Luthra <j-luthra@ti.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/dmaengine.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+#include <media/mipi-csi2.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-mc.h>
+#include <media/videobuf2-dma-contig.h>
+
+#define TI_CSI2RX_MODULE_NAME "j721e-csi2rx"
+
+#define SHIM_CNTL 0x10
+#define SHIM_CNTL_PIX_RST BIT(0)
+
+#define SHIM_DMACNTX 0x20
+#define SHIM_DMACNTX_EN BIT(31)
+#define SHIM_DMACNTX_YUV422 GENMASK(27, 26)
+#define SHIM_DMACNTX_SIZE GENMASK(21, 20)
+#define SHIM_DMACNTX_FMT GENMASK(5, 0)
+#define SHIM_DMACNTX_YUV422_MODE_11 3
+#define SHIM_DMACNTX_SIZE_8 0
+#define SHIM_DMACNTX_SIZE_16 1
+#define SHIM_DMACNTX_SIZE_32 2
+
+#define SHIM_PSI_CFG0 0x24
+#define SHIM_PSI_CFG0_SRC_TAG GENMASK(15, 0)
+#define SHIM_PSI_CFG0_DST_TAG GENMASK(31, 16)
+
+#define PSIL_WORD_SIZE_BYTES 16
+/*
+ * There are no hard limits on the width or height. The DMA engine can handle
+ * all sizes. The max width and height are arbitrary numbers for this driver.
+ * Use 16K * 16K as the arbitrary limit. It is large enough that it is unlikely
+ * the limit will be hit in practice.
+ */
+#define MAX_WIDTH_BYTES SZ_16K
+#define MAX_HEIGHT_LINES SZ_16K
+
+#define DRAIN_TIMEOUT_MS 50
+#define DRAIN_BUFFER_SIZE SZ_32K
+
+struct ti_csi2rx_fmt {
+ u32 fourcc; /* Four character code. */
+ u32 code; /* Mbus code. */
+ u32 csi_dt; /* CSI Data type. */
+ u8 bpp; /* Bits per pixel. */
+ u8 size; /* Data size shift when unpacking. */
+};
+
+struct ti_csi2rx_buffer {
+ /* Common v4l2 buffer. Must be first. */
+ struct vb2_v4l2_buffer vb;
+ struct list_head list;
+ struct ti_csi2rx_dev *csi;
+};
+
+enum ti_csi2rx_dma_state {
+ TI_CSI2RX_DMA_STOPPED, /* Streaming not started yet. */
+ TI_CSI2RX_DMA_IDLE, /* Streaming but no pending DMA operation. */
+ TI_CSI2RX_DMA_ACTIVE, /* Streaming and pending DMA operation. */
+};
+
+struct ti_csi2rx_dma {
+ /* Protects all fields in this struct. */
+ spinlock_t lock;
+ struct dma_chan *chan;
+ /* Buffers queued to the driver, waiting to be processed by DMA. */
+ struct list_head queue;
+ enum ti_csi2rx_dma_state state;
+ /*
+ * Queue of buffers submitted to DMA engine.
+ */
+ struct list_head submitted;
+ /* Buffer to drain stale data from PSI-L endpoint */
+ struct {
+ void *vaddr;
+ dma_addr_t paddr;
+ size_t len;
+ } drain;
+};
+
+struct ti_csi2rx_dev {
+ struct device *dev;
+ void __iomem *shim;
+ struct v4l2_device v4l2_dev;
+ struct video_device vdev;
+ struct media_device mdev;
+ struct media_pipeline pipe;
+ struct media_pad pad;
+ struct v4l2_async_notifier notifier;
+ struct v4l2_subdev *source;
+ struct vb2_queue vidq;
+ struct mutex mutex; /* To serialize ioctls. */
+ struct v4l2_format v_fmt;
+ struct ti_csi2rx_dma dma;
+ u32 sequence;
+};
+
+static const struct ti_csi2rx_fmt ti_csi2rx_formats[] = {
+ {
+ .fourcc = V4L2_PIX_FMT_YUYV,
+ .code = MEDIA_BUS_FMT_YUYV8_1X16,
+ .csi_dt = MIPI_CSI2_DT_YUV422_8B,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_UYVY,
+ .code = MEDIA_BUS_FMT_UYVY8_1X16,
+ .csi_dt = MIPI_CSI2_DT_YUV422_8B,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_YVYU,
+ .code = MEDIA_BUS_FMT_YVYU8_1X16,
+ .csi_dt = MIPI_CSI2_DT_YUV422_8B,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_VYUY,
+ .code = MEDIA_BUS_FMT_VYUY8_1X16,
+ .csi_dt = MIPI_CSI2_DT_YUV422_8B,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SBGGR8,
+ .code = MEDIA_BUS_FMT_SBGGR8_1X8,
+ .csi_dt = MIPI_CSI2_DT_RAW8,
+ .bpp = 8,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SGBRG8,
+ .code = MEDIA_BUS_FMT_SGBRG8_1X8,
+ .csi_dt = MIPI_CSI2_DT_RAW8,
+ .bpp = 8,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SGRBG8,
+ .code = MEDIA_BUS_FMT_SGRBG8_1X8,
+ .csi_dt = MIPI_CSI2_DT_RAW8,
+ .bpp = 8,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SRGGB8,
+ .code = MEDIA_BUS_FMT_SRGGB8_1X8,
+ .csi_dt = MIPI_CSI2_DT_RAW8,
+ .bpp = 8,
+ .size = SHIM_DMACNTX_SIZE_8,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SBGGR10,
+ .code = MEDIA_BUS_FMT_SBGGR10_1X10,
+ .csi_dt = MIPI_CSI2_DT_RAW10,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_16,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SGBRG10,
+ .code = MEDIA_BUS_FMT_SGBRG10_1X10,
+ .csi_dt = MIPI_CSI2_DT_RAW10,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_16,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SGRBG10,
+ .code = MEDIA_BUS_FMT_SGRBG10_1X10,
+ .csi_dt = MIPI_CSI2_DT_RAW10,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_16,
+ }, {
+ .fourcc = V4L2_PIX_FMT_SRGGB10,
+ .code = MEDIA_BUS_FMT_SRGGB10_1X10,
+ .csi_dt = MIPI_CSI2_DT_RAW10,
+ .bpp = 16,
+ .size = SHIM_DMACNTX_SIZE_16,
+ },
+
+ /* More formats can be supported but they are not listed for now. */
+};
+
+/* Forward declaration needed by ti_csi2rx_dma_callback. */
+static int ti_csi2rx_start_dma(struct ti_csi2rx_dev *csi,
+ struct ti_csi2rx_buffer *buf);
+
+static const struct ti_csi2rx_fmt *find_format_by_fourcc(u32 pixelformat)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(ti_csi2rx_formats); i++) {
+ if (ti_csi2rx_formats[i].fourcc == pixelformat)
+ return &ti_csi2rx_formats[i];
+ }
+
+ return NULL;
+}
+
+static const struct ti_csi2rx_fmt *find_format_by_code(u32 code)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(ti_csi2rx_formats); i++) {
+ if (ti_csi2rx_formats[i].code == code)
+ return &ti_csi2rx_formats[i];
+ }
+
+ return NULL;
+}
+
+static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
+ struct v4l2_format *v4l2_fmt)
+{
+ struct v4l2_pix_format *pix = &v4l2_fmt->fmt.pix;
+ unsigned int pixels_in_word;
+
+ pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / csi_fmt->bpp;
+
+ /* Clamp width and height to sensible maximums (16K x 16K) */
+ pix->width = clamp_t(unsigned int, pix->width,
+ pixels_in_word,
+ MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);
+ pix->height = clamp_t(unsigned int, pix->height, 1, MAX_HEIGHT_LINES);
+
+ /* Width should be a multiple of transfer word-size */
+ pix->width = rounddown(pix->width, pixels_in_word);
+
+ v4l2_fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ pix->pixelformat = csi_fmt->fourcc;
+ pix->bytesperline = pix->width * (csi_fmt->bpp / 8);
+ pix->sizeimage = pix->bytesperline * pix->height;
+}
+
+static int ti_csi2rx_querycap(struct file *file, void *priv,
+ struct v4l2_capability *cap)
+{
+ strscpy(cap->driver, TI_CSI2RX_MODULE_NAME, sizeof(cap->driver));
+ strscpy(cap->card, TI_CSI2RX_MODULE_NAME, sizeof(cap->card));
+
+ return 0;
+}
+
+static int ti_csi2rx_enum_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_fmtdesc *f)
+{
+ const struct ti_csi2rx_fmt *fmt = NULL;
+
+ if (f->mbus_code) {
+ /* 1-to-1 mapping between bus formats and pixel formats */
+ if (f->index > 0)
+ return -EINVAL;
+
+ fmt = find_format_by_code(f->mbus_code);
+ } else {
+ if (f->index >= ARRAY_SIZE(ti_csi2rx_formats))
+ return -EINVAL;
+
+ fmt = &ti_csi2rx_formats[f->index];
+ }
+
+ if (!fmt)
+ return -EINVAL;
+
+ f->pixelformat = fmt->fourcc;
+ memset(f->reserved, 0, sizeof(f->reserved));
+ f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+ return 0;
+}
+
+static int ti_csi2rx_g_fmt_vid_cap(struct file *file, void *prov,
+ struct v4l2_format *f)
+{
+ struct ti_csi2rx_dev *csi = video_drvdata(file);
+
+ *f = csi->v_fmt;
+
+ return 0;
+}
+
+static int ti_csi2rx_try_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ const struct ti_csi2rx_fmt *fmt;
+
+ /*
+ * Default to the first format if the requested pixel format code isn't
+ * supported.
+ */
+ fmt = find_format_by_fourcc(f->fmt.pix.pixelformat);
+ if (!fmt)
+ fmt = &ti_csi2rx_formats[0];
+
+ /* Interlaced formats are not supported. */
+ f->fmt.pix.field = V4L2_FIELD_NONE;
+
+ ti_csi2rx_fill_fmt(fmt, f);
+
+ return 0;
+}
+
+static int ti_csi2rx_s_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ struct ti_csi2rx_dev *csi = video_drvdata(file);
+ struct vb2_queue *q = &csi->vidq;
+ int ret;
+
+ if (vb2_is_busy(q))
+ return -EBUSY;
+
+ ret = ti_csi2rx_try_fmt_vid_cap(file, priv, f);
+ if (ret < 0)
+ return ret;
+
+ csi->v_fmt = *f;
+
+ return 0;
+}
+
+static int ti_csi2rx_enum_framesizes(struct file *file, void *fh,
+ struct v4l2_frmsizeenum *fsize)
+{
+ const struct ti_csi2rx_fmt *fmt;
+ unsigned int pixels_in_word;
+
+ fmt = find_format_by_fourcc(fsize->pixel_format);
+ if (!fmt || fsize->index != 0)
+ return -EINVAL;
+
+ /*
+ * Number of pixels in one PSI-L word. The transfer happens in multiples
+ * of PSI-L word sizes.
+ */
+ pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / fmt->bpp;
+
+ fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
+ fsize->stepwise.min_width = pixels_in_word;
+ fsize->stepwise.max_width = rounddown(MAX_WIDTH_BYTES * 8 / fmt->bpp,
+ pixels_in_word);
+ fsize->stepwise.step_width = pixels_in_word;
+ fsize->stepwise.min_height = 1;
+ fsize->stepwise.max_height = MAX_HEIGHT_LINES;
+ fsize->stepwise.step_height = 1;
+
+ return 0;
+}
+
+static const struct v4l2_ioctl_ops csi_ioctl_ops = {
+ .vidioc_querycap = ti_csi2rx_querycap,
+ .vidioc_enum_fmt_vid_cap = ti_csi2rx_enum_fmt_vid_cap,
+ .vidioc_try_fmt_vid_cap = ti_csi2rx_try_fmt_vid_cap,
+ .vidioc_g_fmt_vid_cap = ti_csi2rx_g_fmt_vid_cap,
+ .vidioc_s_fmt_vid_cap = ti_csi2rx_s_fmt_vid_cap,
+ .vidioc_enum_framesizes = ti_csi2rx_enum_framesizes,
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_expbuf = vb2_ioctl_expbuf,
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
+};
+
+static const struct v4l2_file_operations csi_fops = {
+ .owner = THIS_MODULE,
+ .open = v4l2_fh_open,
+ .release = vb2_fop_release,
+ .read = vb2_fop_read,
+ .poll = vb2_fop_poll,
+ .unlocked_ioctl = video_ioctl2,
+ .mmap = vb2_fop_mmap,
+};
+
+static int csi_async_notifier_bound(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *subdev,
+ struct v4l2_async_connection *asc)
+{
+ struct ti_csi2rx_dev *csi = dev_get_drvdata(notifier->v4l2_dev->dev);
+
+ csi->source = subdev;
+
+ return 0;
+}
+
+static int csi_async_notifier_complete(struct v4l2_async_notifier *notifier)
+{
+ struct ti_csi2rx_dev *csi = dev_get_drvdata(notifier->v4l2_dev->dev);
+ struct video_device *vdev = &csi->vdev;
+ int ret;
+
+ ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
+ if (ret)
+ return ret;
+
+ ret = v4l2_create_fwnode_links_to_pad(csi->source, &csi->pad,
+ MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
+
+ if (ret) {
+ video_unregister_device(vdev);
+ return ret;
+ }
+
+ ret = v4l2_device_register_subdev_nodes(&csi->v4l2_dev);
+ if (ret)
+ video_unregister_device(vdev);
+
+ return ret;
+}
+
+static const struct v4l2_async_notifier_operations csi_async_notifier_ops = {
+ .bound = csi_async_notifier_bound,
+ .complete = csi_async_notifier_complete,
+};
+
+static int ti_csi2rx_notifier_register(struct ti_csi2rx_dev *csi)
+{
+ struct fwnode_handle *fwnode;
+ struct v4l2_async_connection *asc;
+ struct device_node *node;
+ int ret;
+
+ node = of_get_child_by_name(csi->dev->of_node, "csi-bridge");
+ if (!node)
+ return -EINVAL;
+
+ fwnode = of_fwnode_handle(node);
+ if (!fwnode) {
+ of_node_put(node);
+ return -EINVAL;
+ }
+
+ v4l2_async_nf_init(&csi->notifier, &csi->v4l2_dev);
+ csi->notifier.ops = &csi_async_notifier_ops;
+
+ asc = v4l2_async_nf_add_fwnode(&csi->notifier, fwnode,
+ struct v4l2_async_connection);
+ of_node_put(node);
+ if (IS_ERR(asc)) {
+ v4l2_async_nf_cleanup(&csi->notifier);
+ return PTR_ERR(asc);
+ }
+
+ ret = v4l2_async_nf_register(&csi->notifier);
+ if (ret) {
+ v4l2_async_nf_cleanup(&csi->notifier);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ti_csi2rx_setup_shim(struct ti_csi2rx_dev *csi)
+{
+ const struct ti_csi2rx_fmt *fmt;
+ unsigned int reg;
+
+ fmt = find_format_by_fourcc(csi->v_fmt.fmt.pix.pixelformat);
+
+ /* De-assert the pixel interface reset. */
+ reg = SHIM_CNTL_PIX_RST;
+ writel(reg, csi->shim + SHIM_CNTL);
+
+ reg = SHIM_DMACNTX_EN;
+ reg |= FIELD_PREP(SHIM_DMACNTX_FMT, fmt->csi_dt);
+
+ /*
+ * The hardware assumes incoming YUV422 8-bit data on MIPI CSI2 bus
+ * follows the spec and is packed in the order U0 -> Y0 -> V0 -> Y1 ->
+ * ...
+ *
+ * There is an option to swap the bytes around before storing in
+ * memory, to achieve different pixel formats:
+ *
+ * Byte3 <----------- Byte0
+ * [ Y1 ][ V0 ][ Y0 ][ U0 ] MODE 11
+ * [ Y1 ][ U0 ][ Y0 ][ V0 ] MODE 10
+ * [ V0 ][ Y1 ][ U0 ][ Y0 ] MODE 01
+ * [ U0 ][ Y1 ][ V0 ][ Y0 ] MODE 00
+ *
+ * We don't have any requirement to change pixelformat from what is
+ * coming from the source, so we keep it in MODE 11, which does not
+ * swap any bytes when storing in memory.
+ */
+ switch (fmt->fourcc) {
+ case V4L2_PIX_FMT_UYVY:
+ case V4L2_PIX_FMT_VYUY:
+ case V4L2_PIX_FMT_YUYV:
+ case V4L2_PIX_FMT_YVYU:
+ reg |= FIELD_PREP(SHIM_DMACNTX_YUV422,
+ SHIM_DMACNTX_YUV422_MODE_11);
+ break;
+ default:
+ /* Ignore if not YUV 4:2:2 */
+ break;
+ }
+
+ reg |= FIELD_PREP(SHIM_DMACNTX_SIZE, fmt->size);
+
+ writel(reg, csi->shim + SHIM_DMACNTX);
+
+ reg = FIELD_PREP(SHIM_PSI_CFG0_SRC_TAG, 0) |
+ FIELD_PREP(SHIM_PSI_CFG0_DST_TAG, 0);
+ writel(reg, csi->shim + SHIM_PSI_CFG0);
+}
+
+static void ti_csi2rx_drain_callback(void *param)
+{
+ struct completion *drain_complete = param;
+
+ complete(drain_complete);
+}
+
+/*
+ * Drain the stale data left at the PSI-L endpoint.
+ *
+ * This might happen if no buffers are queued in time but source is still
+ * streaming. In multi-stream scenarios this can happen when one stream is
+ * stopped but other is still streaming, and thus module-level pixel reset is
+ * not asserted.
+ *
+ * To prevent that stale data corrupting the subsequent transactions, it is
+ * required to issue DMA requests to drain it out.
+ */
+static int ti_csi2rx_drain_dma(struct ti_csi2rx_dev *csi)
+{
+ struct dma_async_tx_descriptor *desc;
+ struct completion drain_complete;
+ dma_cookie_t cookie;
+ int ret;
+
+ init_completion(&drain_complete);
+
+ desc = dmaengine_prep_slave_single(csi->dma.chan, csi->dma.drain.paddr,
+ csi->dma.drain.len, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc) {
+ ret = -EIO;
+ goto out;
+ }
+
+ desc->callback = ti_csi2rx_drain_callback;
+ desc->callback_param = &drain_complete;
+
+ cookie = dmaengine_submit(desc);
+ ret = dma_submit_error(cookie);
+ if (ret)
+ goto out;
+
+ dma_async_issue_pending(csi->dma.chan);
+
+ if (!wait_for_completion_timeout(&drain_complete,
+ msecs_to_jiffies(DRAIN_TIMEOUT_MS))) {
+ dmaengine_terminate_sync(csi->dma.chan);
+ dev_dbg(csi->dev, "DMA transfer timed out for drain buffer\n");
+ ret = -ETIMEDOUT;
+ goto out;
+ }
+out:
+ return ret;
+}
+
+static void ti_csi2rx_dma_callback(void *param)
+{
+ struct ti_csi2rx_buffer *buf = param;
+ struct ti_csi2rx_dev *csi = buf->csi;
+ struct ti_csi2rx_dma *dma = &csi->dma;
+ unsigned long flags;
+
+ /*
+ * TODO: Derive the sequence number from the CSI2RX frame number
+ * hardware monitor registers.
+ */
+ buf->vb.vb2_buf.timestamp = ktime_get_ns();
+ buf->vb.sequence = csi->sequence++;
+
+ spin_lock_irqsave(&dma->lock, flags);
+
+ WARN_ON(!list_is_first(&buf->list, &dma->submitted));
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
+ list_del(&buf->list);
+
+ /* If there are more buffers to process then start their transfer. */
+ while (!list_empty(&dma->queue)) {
+ buf = list_entry(dma->queue.next, struct ti_csi2rx_buffer, list);
+
+ if (ti_csi2rx_start_dma(csi, buf)) {
+ dev_err(csi->dev, "Failed to queue the next buffer for DMA\n");
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ } else {
+ list_move_tail(&buf->list, &dma->submitted);
+ }
+ }
+
+ if (list_empty(&dma->submitted))
+ dma->state = TI_CSI2RX_DMA_IDLE;
+
+ spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+static int ti_csi2rx_start_dma(struct ti_csi2rx_dev *csi,
+ struct ti_csi2rx_buffer *buf)
+{
+ unsigned long addr;
+ struct dma_async_tx_descriptor *desc;
+ size_t len = csi->v_fmt.fmt.pix.sizeimage;
+ dma_cookie_t cookie;
+ int ret = 0;
+
+ addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
+ desc = dmaengine_prep_slave_single(csi->dma.chan, addr, len,
+ DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc)
+ return -EIO;
+
+ desc->callback = ti_csi2rx_dma_callback;
+ desc->callback_param = buf;
+
+ cookie = dmaengine_submit(desc);
+ ret = dma_submit_error(cookie);
+ if (ret)
+ return ret;
+
+ dma_async_issue_pending(csi->dma.chan);
+
+ return 0;
+}
+
+static void ti_csi2rx_stop_dma(struct ti_csi2rx_dev *csi)
+{
+ struct ti_csi2rx_dma *dma = &csi->dma;
+ enum ti_csi2rx_dma_state state;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&dma->lock, flags);
+ state = csi->dma.state;
+ dma->state = TI_CSI2RX_DMA_STOPPED;
+ spin_unlock_irqrestore(&dma->lock, flags);
+
+ if (state != TI_CSI2RX_DMA_STOPPED) {
+ /*
+ * Normal DMA termination does not clean up pending data on
+ * the endpoint if multiple streams are running and only one
+ * is stopped, as the module-level pixel reset cannot be
+ * enforced before terminating DMA.
+ */
+ ret = ti_csi2rx_drain_dma(csi);
+ if (ret && ret != -ETIMEDOUT)
+ dev_warn(csi->dev,
+ "Failed to drain DMA. Next frame might be bogus\n");
+ }
+
+ ret = dmaengine_terminate_sync(csi->dma.chan);
+ if (ret)
+ dev_err(csi->dev, "Failed to stop DMA: %d\n", ret);
+}
+
+static void ti_csi2rx_cleanup_buffers(struct ti_csi2rx_dev *csi,
+ enum vb2_buffer_state state)
+{
+ struct ti_csi2rx_dma *dma = &csi->dma;
+ struct ti_csi2rx_buffer *buf, *tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dma->lock, flags);
+ list_for_each_entry_safe(buf, tmp, &csi->dma.queue, list) {
+ list_del(&buf->list);
+ vb2_buffer_done(&buf->vb.vb2_buf, state);
+ }
+ list_for_each_entry_safe(buf, tmp, &csi->dma.submitted, list) {
+ list_del(&buf->list);
+ vb2_buffer_done(&buf->vb.vb2_buf, state);
+ }
+ spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+static int ti_csi2rx_queue_setup(struct vb2_queue *q, unsigned int *nbuffers,
+ unsigned int *nplanes, unsigned int sizes[],
+ struct device *alloc_devs[])
+{
+ struct ti_csi2rx_dev *csi = vb2_get_drv_priv(q);
+ unsigned int size = csi->v_fmt.fmt.pix.sizeimage;
+
+ if (*nplanes) {
+ if (sizes[0] < size)
+ return -EINVAL;
+ size = sizes[0];
+ }
+
+ *nplanes = 1;
+ sizes[0] = size;
+
+ return 0;
+}
+
+static int ti_csi2rx_buffer_prepare(struct vb2_buffer *vb)
+{
+ struct ti_csi2rx_dev *csi = vb2_get_drv_priv(vb->vb2_queue);
+ unsigned long size = csi->v_fmt.fmt.pix.sizeimage;
+
+ if (vb2_plane_size(vb, 0) < size) {
+ dev_err(csi->dev, "Data will not fit into plane\n");
+ return -EINVAL;
+ }
+
+ vb2_set_plane_payload(vb, 0, size);
+ return 0;
+}
+
+static void ti_csi2rx_buffer_queue(struct vb2_buffer *vb)
+{
+ struct ti_csi2rx_dev *csi = vb2_get_drv_priv(vb->vb2_queue);
+ struct ti_csi2rx_buffer *buf;
+ struct ti_csi2rx_dma *dma = &csi->dma;
+ bool restart_dma = false;
+ unsigned long flags = 0;
+ int ret;
+
+ buf = container_of(vb, struct ti_csi2rx_buffer, vb.vb2_buf);
+ buf->csi = csi;
+
+ spin_lock_irqsave(&dma->lock, flags);
+ /*
+ * Usually the DMA callback takes care of queueing the pending buffers.
+ * But if DMA has stalled due to lack of buffers, restart it now.
+ */
+ if (dma->state == TI_CSI2RX_DMA_IDLE) {
+ /*
+ * Do not restart DMA with the lock held because
+ * ti_csi2rx_drain_dma() might block for completion.
+ * There won't be a race on queueing DMA anyway since the
+ * callback is not being fired.
+ */
+ restart_dma = true;
+ dma->state = TI_CSI2RX_DMA_ACTIVE;
+ } else {
+ list_add_tail(&buf->list, &dma->queue);
+ }
+ spin_unlock_irqrestore(&dma->lock, flags);
+
+ if (restart_dma) {
+ /*
+ * Once frames start dropping, some data gets stuck in the DMA
+ * pipeline somewhere. So the first DMA transfer after frame
+ * drops gives a partial frame. This is obviously not useful to
+ * the application and will only confuse it. Issue a DMA
+ * transaction to drain that up.
+ */
+ ret = ti_csi2rx_drain_dma(csi);
+ if (ret && ret != -ETIMEDOUT)
+ dev_warn(csi->dev,
+ "Failed to drain DMA. Next frame might be bogus\n");
+
+ ret = ti_csi2rx_start_dma(csi, buf);
+ if (ret) {
+ dev_err(csi->dev, "Failed to start DMA: %d\n", ret);
+ spin_lock_irqsave(&dma->lock, flags);
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ dma->state = TI_CSI2RX_DMA_IDLE;
+ spin_unlock_irqrestore(&dma->lock, flags);
+ } else {
+ spin_lock_irqsave(&dma->lock, flags);
+ list_add_tail(&buf->list, &dma->submitted);
+ spin_unlock_irqrestore(&dma->lock, flags);
+ }
+ }
+}
+
+static int ti_csi2rx_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+ struct ti_csi2rx_dev *csi = vb2_get_drv_priv(vq);
+ struct ti_csi2rx_dma *dma = &csi->dma;
+ struct ti_csi2rx_buffer *buf;
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&dma->lock, flags);
+ if (list_empty(&dma->queue))
+ ret = -EIO;
+ spin_unlock_irqrestore(&dma->lock, flags);
+ if (ret)
+ return ret;
+
+ ret = video_device_pipeline_start(&csi->vdev, &csi->pipe);
+ if (ret)
+ goto err;
+
+ ti_csi2rx_setup_shim(csi);
+
+ csi->sequence = 0;
+
+ spin_lock_irqsave(&dma->lock, flags);
+ buf = list_entry(dma->queue.next, struct ti_csi2rx_buffer, list);
+
+ ret = ti_csi2rx_start_dma(csi, buf);
+ if (ret) {
+ dev_err(csi->dev, "Failed to start DMA: %d\n", ret);
+ spin_unlock_irqrestore(&dma->lock, flags);
+ goto err_pipeline;
+ }
+
+ list_move_tail(&buf->list, &dma->submitted);
+ dma->state = TI_CSI2RX_DMA_ACTIVE;
+ spin_unlock_irqrestore(&dma->lock, flags);
+
+ ret = v4l2_subdev_call(csi->source, video, s_stream, 1);
+ if (ret)
+ goto err_dma;
+
+ return 0;
+
+err_dma:
+ ti_csi2rx_stop_dma(csi);
+err_pipeline:
+ video_device_pipeline_stop(&csi->vdev);
+ writel(0, csi->shim + SHIM_CNTL);
+ writel(0, csi->shim + SHIM_DMACNTX);
+err:
+ ti_csi2rx_cleanup_buffers(csi, VB2_BUF_STATE_QUEUED);
+ return ret;
+}
+
+static void ti_csi2rx_stop_streaming(struct vb2_queue *vq)
+{
+ struct ti_csi2rx_dev *csi = vb2_get_drv_priv(vq);
+ int ret;
+
+ video_device_pipeline_stop(&csi->vdev);
+
+ writel(0, csi->shim + SHIM_CNTL);
+ writel(0, csi->shim + SHIM_DMACNTX);
+
+ ret = v4l2_subdev_call(csi->source, video, s_stream, 0);
+ if (ret)
+ dev_err(csi->dev, "Failed to stop subdev stream\n");
+
+ ti_csi2rx_stop_dma(csi);
+ ti_csi2rx_cleanup_buffers(csi, VB2_BUF_STATE_ERROR);
+}
+
+static const struct vb2_ops csi_vb2_qops = {
+ .queue_setup = ti_csi2rx_queue_setup,
+ .buf_prepare = ti_csi2rx_buffer_prepare,
+ .buf_queue = ti_csi2rx_buffer_queue,
+ .start_streaming = ti_csi2rx_start_streaming,
+ .stop_streaming = ti_csi2rx_stop_streaming,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+};
+
+static int ti_csi2rx_init_vb2q(struct ti_csi2rx_dev *csi)
+{
+ struct vb2_queue *q = &csi->vidq;
+ int ret;
+
+ q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ q->io_modes = VB2_MMAP | VB2_DMABUF;
+ q->drv_priv = csi;
+ q->buf_struct_size = sizeof(struct ti_csi2rx_buffer);
+ q->ops = &csi_vb2_qops;
+ q->mem_ops = &vb2_dma_contig_memops;
+ q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+ q->dev = dmaengine_get_dma_device(csi->dma.chan);
+ q->lock = &csi->mutex;
+ q->min_buffers_needed = 1;
+
+ ret = vb2_queue_init(q);
+ if (ret)
+ return ret;
+
+ csi->vdev.queue = q;
+
+ return 0;
+}
+
+static int ti_csi2rx_link_validate(struct media_link *link)
+{
+ struct media_entity *entity = link->sink->entity;
+ struct video_device *vdev = media_entity_to_video_device(entity);
+ struct ti_csi2rx_dev *csi = container_of(vdev, struct ti_csi2rx_dev, vdev);
+ struct v4l2_pix_format *csi_fmt = &csi->v_fmt.fmt.pix;
+ struct v4l2_subdev_format source_fmt = {
+ .which = V4L2_SUBDEV_FORMAT_ACTIVE,
+ .pad = link->source->index,
+ };
+ const struct ti_csi2rx_fmt *ti_fmt;
+ int ret;
+
+ ret = v4l2_subdev_call_state_active(csi->source, pad,
+ get_fmt, &source_fmt);
+ if (ret)
+ return ret;
+
+ if (source_fmt.format.width != csi_fmt->width) {
+ dev_dbg(csi->dev, "Width does not match (source %u, sink %u)\n",
+ source_fmt.format.width, csi_fmt->width);
+ return -EPIPE;
+ }
+
+ if (source_fmt.format.height != csi_fmt->height) {
+ dev_dbg(csi->dev, "Height does not match (source %u, sink %u)\n",
+ source_fmt.format.height, csi_fmt->height);
+ return -EPIPE;
+ }
+
+ if (source_fmt.format.field != csi_fmt->field &&
+ csi_fmt->field != V4L2_FIELD_NONE) {
+ dev_dbg(csi->dev, "Field does not match (source %u, sink %u)\n",
+ source_fmt.format.field, csi_fmt->field);
+ return -EPIPE;
+ }
+
+ ti_fmt = find_format_by_code(source_fmt.format.code);
+ if (!ti_fmt) {
+ dev_dbg(csi->dev, "Media bus format 0x%x not supported\n",
+ source_fmt.format.code);
+ return -EPIPE;
+ }
+
+ if (ti_fmt->fourcc != csi_fmt->pixelformat) {
+ dev_dbg(csi->dev,
+ "Cannot transform source fmt 0x%x to sink fmt 0x%x\n",
+ ti_fmt->fourcc, csi_fmt->pixelformat);
+ return -EPIPE;
+ }
+
+ return 0;
+}
+
+static const struct media_entity_operations ti_csi2rx_video_entity_ops = {
+ .link_validate = ti_csi2rx_link_validate,
+};
+
+static int ti_csi2rx_init_dma(struct ti_csi2rx_dev *csi)
+{
+ struct dma_slave_config cfg = {
+ .src_addr_width = DMA_SLAVE_BUSWIDTH_16_BYTES,
+ };
+ int ret;
+
+ INIT_LIST_HEAD(&csi->dma.queue);
+ INIT_LIST_HEAD(&csi->dma.submitted);
+ spin_lock_init(&csi->dma.lock);
+
+ csi->dma.state = TI_CSI2RX_DMA_STOPPED;
+
+ csi->dma.chan = dma_request_chan(csi->dev, "rx0");
+ if (IS_ERR(csi->dma.chan))
+ return PTR_ERR(csi->dma.chan);
+
+ ret = dmaengine_slave_config(csi->dma.chan, &cfg);
+ if (ret) {
+ dma_release_channel(csi->dma.chan);
+ return ret;
+ }
+
+ csi->dma.drain.len = DRAIN_BUFFER_SIZE;
+ csi->dma.drain.vaddr = dma_alloc_coherent(csi->dev, csi->dma.drain.len,
+ &csi->dma.drain.paddr,
+ GFP_KERNEL);
+ if (!csi->dma.drain.vaddr)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int ti_csi2rx_v4l2_init(struct ti_csi2rx_dev *csi)
+{
+ struct media_device *mdev = &csi->mdev;
+ struct video_device *vdev = &csi->vdev;
+ const struct ti_csi2rx_fmt *fmt;
+ struct v4l2_pix_format *pix_fmt = &csi->v_fmt.fmt.pix;
+ int ret;
+
+ fmt = find_format_by_fourcc(V4L2_PIX_FMT_UYVY);
+ if (!fmt)
+ return -EINVAL;
+
+ pix_fmt->width = 640;
+ pix_fmt->height = 480;
+ pix_fmt->field = V4L2_FIELD_NONE;
+ pix_fmt->colorspace = V4L2_COLORSPACE_SRGB;
+ pix_fmt->ycbcr_enc = V4L2_YCBCR_ENC_601,
+ pix_fmt->quantization = V4L2_QUANTIZATION_LIM_RANGE,
+ pix_fmt->xfer_func = V4L2_XFER_FUNC_SRGB,
+
+ ti_csi2rx_fill_fmt(fmt, &csi->v_fmt);
+
+ mdev->dev = csi->dev;
+ mdev->hw_revision = 1;
+ strscpy(mdev->model, "TI-CSI2RX", sizeof(mdev->model));
+
+ media_device_init(mdev);
+
+ strscpy(vdev->name, TI_CSI2RX_MODULE_NAME, sizeof(vdev->name));
+ vdev->v4l2_dev = &csi->v4l2_dev;
+ vdev->vfl_dir = VFL_DIR_RX;
+ vdev->fops = &csi_fops;
+ vdev->ioctl_ops = &csi_ioctl_ops;
+ vdev->release = video_device_release_empty;
+ vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
+ V4L2_CAP_IO_MC;
+ vdev->lock = &csi->mutex;
+ video_set_drvdata(vdev, csi);
+
+ csi->pad.flags = MEDIA_PAD_FL_SINK;
+ vdev->entity.ops = &ti_csi2rx_video_entity_ops;
+ ret = media_entity_pads_init(&csi->vdev.entity, 1, &csi->pad);
+ if (ret)
+ return ret;
+
+ csi->v4l2_dev.mdev = mdev;
+
+ ret = v4l2_device_register(csi->dev, &csi->v4l2_dev);
+ if (ret)
+ return ret;
+
+ ret = media_device_register(mdev);
+ if (ret) {
+ v4l2_device_unregister(&csi->v4l2_dev);
+ media_device_cleanup(mdev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ti_csi2rx_cleanup_dma(struct ti_csi2rx_dev *csi)
+{
+ dma_free_coherent(csi->dev, csi->dma.drain.len,
+ csi->dma.drain.vaddr, csi->dma.drain.paddr);
+ csi->dma.drain.vaddr = NULL;
+ dma_release_channel(csi->dma.chan);
+}
+
+static void ti_csi2rx_cleanup_v4l2(struct ti_csi2rx_dev *csi)
+{
+ media_device_unregister(&csi->mdev);
+ v4l2_device_unregister(&csi->v4l2_dev);
+ media_device_cleanup(&csi->mdev);
+}
+
+static void ti_csi2rx_cleanup_subdev(struct ti_csi2rx_dev *csi)
+{
+ v4l2_async_nf_unregister(&csi->notifier);
+ v4l2_async_nf_cleanup(&csi->notifier);
+}
+
+static void ti_csi2rx_cleanup_vb2q(struct ti_csi2rx_dev *csi)
+{
+ vb2_queue_release(&csi->vidq);
+}
+
+static int ti_csi2rx_probe(struct platform_device *pdev)
+{
+ struct ti_csi2rx_dev *csi;
+ struct resource *res;
+ int ret;
+
+ csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
+ if (!csi)
+ return -ENOMEM;
+
+ csi->dev = &pdev->dev;
+ platform_set_drvdata(pdev, csi);
+
+ mutex_init(&csi->mutex);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ csi->shim = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(csi->shim)) {
+ ret = PTR_ERR(csi->shim);
+ goto err_mutex;
+ }
+
+ ret = ti_csi2rx_init_dma(csi);
+ if (ret)
+ goto err_mutex;
+
+ ret = ti_csi2rx_v4l2_init(csi);
+ if (ret)
+ goto err_dma;
+
+ ret = ti_csi2rx_init_vb2q(csi);
+ if (ret)
+ goto err_v4l2;
+
+ ret = ti_csi2rx_notifier_register(csi);
+ if (ret)
+ goto err_vb2q;
+
+ ret = of_platform_populate(csi->dev->of_node, NULL, NULL, csi->dev);
+ if (ret) {
+ dev_err(csi->dev, "Failed to create children: %d\n", ret);
+ goto err_subdev;
+ }
+
+ return 0;
+
+err_subdev:
+ ti_csi2rx_cleanup_subdev(csi);
+err_vb2q:
+ ti_csi2rx_cleanup_vb2q(csi);
+err_v4l2:
+ ti_csi2rx_cleanup_v4l2(csi);
+err_dma:
+ ti_csi2rx_cleanup_dma(csi);
+err_mutex:
+ mutex_destroy(&csi->mutex);
+ return ret;
+}
+
+static int ti_csi2rx_remove(struct platform_device *pdev)
+{
+ struct ti_csi2rx_dev *csi = platform_get_drvdata(pdev);
+
+ video_unregister_device(&csi->vdev);
+
+ ti_csi2rx_cleanup_vb2q(csi);
+ ti_csi2rx_cleanup_subdev(csi);
+ ti_csi2rx_cleanup_v4l2(csi);
+ ti_csi2rx_cleanup_dma(csi);
+
+ mutex_destroy(&csi->mutex);
+
+ return 0;
+}
+
+static const struct of_device_id ti_csi2rx_of_match[] = {
+ { .compatible = "ti,j721e-csi2rx-shim", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ti_csi2rx_of_match);
+
+static struct platform_driver ti_csi2rx_pdrv = {
+ .probe = ti_csi2rx_probe,
+ .remove = ti_csi2rx_remove,
+ .driver = {
+ .name = TI_CSI2RX_MODULE_NAME,
+ .of_match_table = ti_csi2rx_of_match,
+ },
+};
+
+module_platform_driver(ti_csi2rx_pdrv);
+
+MODULE_DESCRIPTION("TI J721E CSI2 RX Driver");
+MODULE_AUTHOR("Jai Luthra <j-luthra@ti.com>");
+MODULE_LICENSE("GPL");
projects / users / hch / dma-mapping.git / commitdiff