Hello!
On 07/03/2017 03:25 PM, Hans Verkuil wrote:
From: Konstantin Kozhevnikov <Konstantin.Kozhevnikov@xxxxxxxxxxxxxxxxxx>
The image renderer, or the distortion correction engine, is a drawing
processor with a simple instruction system capable of referencing video
capture data or data in an external memory as the 2D texture data and
performing texture mapping and drawing with respect to any shape that is
split into triangular objects.
This V4L2 memory-to-memory device driver only supports image renderer light
extended 4 (IMR-LX4) found in the R-Car gen3 SoCs; the R-Car gen2 support
can be added later...
[Sergei: merged 2 original patches, added the patch description, removed
unrelated parts, added the binding document and the UAPI documentation,
ported the driver to the modern kernel, renamed the UAPI header file and
the guard macros to match the driver name, extended the copyrights, fixed
up Kconfig prompt/depends/help, made use of the BIT/GENMASK() macros,
sorted #include's, replaced 'imr_ctx::crop' array with the 'imr_ctx::rect'
structure, replaced imr_{g|s}_crop() with imr_{g|s}_selection(), completely
rewrote imr_queue_setup(), removed 'imr_format_info::name', moved the
applicable code from imr_buf_queue() to imr_buf_prepare() and moved the
rest of imr_buf_queue() after imr_buf_finish(), assigned 'src_vq->dev' and
'dst_vq->dev' in imr_queue_init(), removed imr_start_streaming(), assigned
'src_vq->dev' and 'dst_vq->dev' in imr_queue_init(), clarified the math in
imt_tri_type_{a|b|c}_length(), clarified the pointer math and avoided casts
to 'void *' in imr_tri_set_type_{a|b|c}(), replaced imr_{reqbufs|querybuf|
dqbuf|expbuf|streamon|streamoff}() with the generic helpers, implemented
vidioc_{create_bufs|prepare_buf}() methods, used ALIGN() macro and merged
the matrix size checks and replaced kmalloc()/copy_from_user() calls with
memdup_user() call in imr_ioctl_map(), moved setting device capabilities
from imr_querycap() to imr_probe(), set the valid default queue format in
imr_probe(), removed leading dots and fixed grammar in the comments, fixed
up the indentation to use tabs where possible, renamed DLSR, CMRCR.
DY1{0|2}, and ICR bits to match the manual, changed the prefixes of the
CMRCR[2]/TRI{M|C}R bits/fields to match the manual, removed non-existent
TRIMR.D{Y|U}D{X|V}M bits, added/used the IMR/{UV|CP}DPOR/SUSR bits/fields/
shifts, separated the register offset/bit #define's, sorted instruction
macros by opcode, removed unsupported LINE instruction, masked the register
address in WTL[2]/WTS instruction macros, moved the display list #define's
after the register #define's, removing the redundant comment, avoided
setting reserved bits when writing CMRCCR[2]/TRIMCR, used the SR bits
instead of a bare number, removed *inline* from .c file, fixed lines over
80 columns, removed useless spaces, comments, parens, operators, casts,
braces, variables, #include's, statements, and even 1 function, added
useful local variable, uppercased and spelled out the abbreviations,
made comment wording more consistent/correct, fixed the comment typos,
reformatted some multiline comments, inserted empty line after declaration,
removed extra empty lines, reordered some local variable desclarations,
removed calls to 4l2_err() on kmalloc() failure, replaced '*' with 'x'
in some format strings for v4l2_dbg(), fixed the error returned by
imr_default(), avoided code duplication in the IRQ handler, used '__packed'
for the UAPI structures, declared 'imr_map_desc::data' as '__u64' instead
of 'void *', switched to '__u{16|32}' in the UAPI header, enclosed the
macro parameters in parens, exchanged the values of IMR_MAP_AUTO{S|D}G
macros.]
As Geert suggested, just replace this with a 'Based-on' line.
OK, the list grew too long indeed. :-)
<snip>
Index: media_tree/drivers/media/platform/rcar_imr.c
===================================================================
--- /dev/null
+++ media_tree/drivers/media/platform/rcar_imr.c
@@ -0,0 +1,1877 @@
<snip>
+/* add reference to the current configuration */
+static struct imr_cfg *imr_cfg_ref(struct imr_ctx *ctx)
imr_cfg_ref -> imr_cfg_ref_get
OK, but imr_cfg_get() seems a better name.
+{
+ struct imr_cfg *cfg = ctx->cfg;
+
+ BUG_ON(!cfg);
Perhaps this can be replaced by:
if (WARN_ON(!cfg))
return NULL;
I'm afraid imr_device_run() will cause oops in this case...
+ cfg->refcount++;
+ return cfg;
+}
+
+/* mesh configuration destructor */
+static void imr_cfg_unref(struct imr_ctx *ctx, struct imr_cfg *cfg)
imr_cfg_unref -> imr_cfg_ref_put
OK, but I'll call it imr_cfg_put().
That follows the standard naming conventions for refcounting.
+{
+ struct imr_device *imr = ctx->imr;
+
+ /* no atomicity is required as operation is locked with device mutex */
+ if (!cfg || --cfg->refcount)
+ return;
+
+ /* release memory allocated for a display list */
+ if (cfg->dl_vaddr)
+ dma_free_writecombine(imr->dev, cfg->dl_size, cfg->dl_vaddr,
+ cfg->dl_dma_addr);
+
+ /* destroy the configuration structure */
+ kfree(cfg);
Add:
ctx->cfg = NULL;
Thanks, makes sense indeed.
[...]
+static int imr_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
+{
+ struct imr_ctx *ctx = fh_to_ctx(priv);
+
+ /* operation is protected with a queue lock */
+ WARN_ON(!mutex_is_locked(&ctx->imr->mutex));
It's guaranteed by the V4L2 core, so this can be dropped safely.
+
+ /* verify the configuration is complete */
+ if (!ctx->cfg) {
+ v4l2_err(&ctx->imr->v4l2_dev,
+ "stream configuration is not complete\n");
+ return -EINVAL;
+ }
Shouldn't this test be done in the buf_prepare callback above? It's
what buf_prepare is for.
Then you can drop this function and use the helper function instead.
OK, will look into this...
+
+ return v4l2_m2m_qbuf(file, ctx->m2m_ctx, buf);
+}
[...]
+static unsigned int imr_poll(struct file *file, struct poll_table_struct
*wait)
+{
+ struct imr_ctx *ctx = fh_to_ctx(file->private_data);
+ struct imr_device *imr = video_drvdata(file);
+ unsigned int res;
+
+ if (mutex_lock_interruptible(&imr->mutex))
+ return -ERESTARTSYS;
+
+ res = v4l2_m2m_poll(file, ctx->m2m_ctx, wait);
+ mutex_unlock(&imr->mutex);
+
+ return res;
+}
Set the struct v4l2_m2m_ctx q_lock field to imr->mutex.
Then you can use v4l2_m2m_fop_poll instead.
Will look into this.
+
+static int imr_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct imr_device *imr = video_drvdata(file);
+ struct imr_ctx *ctx = fh_to_ctx(file->private_data);
+ int ret;
+
+ /* should we protect all M2M operations with mutex? - TBD */
+ if (mutex_lock_interruptible(&imr->mutex))
+ return -ERESTARTSYS;
+
+ ret = v4l2_m2m_mmap(file, ctx->m2m_ctx, vma);
+
+ mutex_unlock(&imr->mutex);
+
+ return ret;
+}
Use v4l2_m2m_fop_mmap. And this is one file operation where you shouldn't lock.
The vb2 core has a special mutex to handle this.
OK, will see.
[...]
+/*******************************************************************************
+ * Device probing/removal interface
+
******************************************************************************/
+
+static int imr_probe(struct platform_device *pdev)
+{
+ struct imr_device *imr;
+ struct resource *res;
+ int ret;
+
+ imr = devm_kzalloc(&pdev->dev, sizeof(*imr), GFP_KERNEL);
+ if (!imr)
+ return -ENOMEM;
+
+ mutex_init(&imr->mutex);
+ spin_lock_init(&imr->lock);
+ imr->dev = &pdev->dev;
+
+ /* memory-mapped registers */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ imr->mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(imr->mmio))
+ return PTR_ERR(imr->mmio);
+
+ /* interrupt service routine registration */
+ imr->irq = ret = platform_get_irq(pdev, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cannot find IRQ\n");
+ return ret;
+ }
+
+ ret = devm_request_irq(&pdev->dev, imr->irq, imr_irq_handler, 0,
+ dev_name(&pdev->dev), imr);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot claim IRQ %d\n", imr->irq);
+ return ret;
+ }
+
+ imr->clock = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(imr->clock)) {
+ dev_err(&pdev->dev, "cannot get clock\n");
+ return PTR_ERR(imr->clock);
+ }
+
+ /* create v4l2 device */
+ ret = v4l2_device_register(&pdev->dev, &imr->v4l2_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to register v4l2 device\n");
+ return ret;
+ }
+
+ /* create mem2mem device handle */
+ imr->m2m_dev = v4l2_m2m_init(&imr_m2m_ops);
+ if (IS_ERR(imr->m2m_dev)) {
+ v4l2_err(&imr->v4l2_dev, "Failed to init mem2mem device\n");
+ ret = PTR_ERR(imr->m2m_dev);
+ goto device_register_rollback;
+ }
+
+ strlcpy(imr->video_dev.name, dev_name(&pdev->dev),
+ sizeof(imr->video_dev.name));
+ imr->video_dev.fops = &imr_fops;
+ imr->video_dev.device_caps = V4L2_CAP_VIDEO_CAPTURE |
+ V4L2_CAP_VIDEO_OUTPUT |
+ V4L2_CAP_VIDEO_M2M | V4L2_CAP_STREAMING;
Only specify V4L2_CAP_VIDEO_M2M | V4L2_CAP_STREAMING.
M2M cannot be combined with CAPTURE and OUTPUT.
OK, sorry about that...
[...]
Index: media_tree/include/uapi/linux/rcar_imr.h
===================================================================
--- /dev/null
+++ media_tree/include/uapi/linux/rcar_imr.h
@@ -0,0 +1,94 @@
+/*
+ * rcar_imr.h -- R-Car IMR-LX4 Driver UAPI
+ *
+ * Copyright (C) 2016-2017 Cogent Embedded, Inc. <source@xxxxxxxxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __RCAR_IMR_H
+#define __RCAR_IMR_H
+
+#include <linux/videodev2.h>
+
+/*******************************************************************************
+ * Mapping specification descriptor
+
******************************************************************************/
+
+struct imr_map_desc {
+ /* mapping types */
+ __u32 type;
+
+ /* total size of the mesh structure */
+ __u32 size;
+
+ /* map-specific user-pointer */
+ __u64 data;
+} __packed;
+
+/* regular mesh specification */
+#define IMR_MAP_MESH (1 << 0)
+
+/* auto-generated source coordinates */
+#define IMR_MAP_AUTOSG (1 << 1)
+
+/* auto-generated destination coordinates */
+#define IMR_MAP_AUTODG (1 << 2)
+
+/* luminance correction flag */
+#define IMR_MAP_LUCE (1 << 3)
+
+/* chromacity correction flag */
chromacity? You probably mean just plain 'chroma'. Ditto below.
Hm, www.translate.ru knows this word. :-)
[...]
Regards,
Hans
MBR, Sergei
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