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From: Eddie James <eajames@linux.vnet.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: linux-media@vger.kernel.org, linux-aspeed@lists.ozlabs.org,
	andrew@aj.id.au, joel@jms.id.au, mchehab@kernel.org,
	openbmc@lists.ozlabs.org,
	Eddie James <eajames@linux.vnet.ibm.com>
Subject: [RFC 0/2] media: platform: Add Aspeed Video Engine driver
Date: Thu, 16 Aug 2018 14:43:19 -0500	[thread overview]
Message-ID: <1534448601-74120-1-git-send-email-eajames@linux.vnet.ibm.com> (raw)

The Video Engine (VE) embedded in the Aspeed AST2400 and AST2500 SOCs
can capture and compress video data from digital or analog sources. With
the Aspeed chip acting as a service processor, the Video Engine can
capture the host processor graphics output.

This series adds a V4L2 driver for the VE, providing a read() interface
only. The driver triggers the hardware to capture the host graphics output
and compress it to JPEG format.

Testing on an AST2500 determined that the videobuf/streaming/mmap interface
was significantly slower than the simple read() interface, so I have not
included the streaming part.

It's also possible to use an automatic mode for the VE such that
re-triggering the HW every frame isn't necessary. However this wasn't
reliable on the AST2400, and probably used more CPU anyway due to excessive
interrupts. It was approximately 15% faster.

Eddie James (2):
  dt-bindings: media: Add Aspeed Video Engine binding documentation
  media: platform: Add Aspeed Video Engine driver

 .../devicetree/bindings/media/aspeed-video.txt     |   25 +
 drivers/media/platform/Kconfig                     |    8 +
 drivers/media/platform/Makefile                    |    1 +
 drivers/media/platform/aspeed-video.c              | 1307 ++++++++++++++++++++
 4 files changed, 1341 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/aspeed-video.txt
 create mode 100644 drivers/media/platform/aspeed-video.c

-- 
1.8.3.1


             reply	other threads:[~2018-08-16 19:43 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-16 19:43 Eddie James [this message]
2018-08-16 19:43 ` [RFC 1/2] dt-bindings: media: Add Aspeed Video Engine binding documentation Eddie James
2018-08-16 21:14   ` Eddie James
2018-08-16 19:43 ` [RFC 2/2] media: platform: Add Aspeed Video Engine driver Eddie James

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