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commitb1f373a11dupstream. VAG power control is improved to fit the manual [1]. This patch fixes as minimum one bug: if customer muxes Headphone to Line-In right after boot, the VAG power remains off that leads to poor sound quality from line-in. I.e. after boot: - Connect sound source to Line-In jack; - Connect headphone to HP jack; - Run following commands: $ amixer set 'Headphone' 80% $ amixer set 'Headphone Mux' LINE_IN Change VAG power on/off control according to the following algorithm: - turn VAG power ON on the 1st incoming event. - keep it ON if there is any active VAG consumer (ADC/DAC/HP/Line-In). - turn VAG power OFF when there is the latest consumer's pre-down event come. - always delay after VAG power OFF to avoid pop. - delay after VAG power ON if the initiative consumer is Line-In, this prevents pop during line-in muxing. According to the data sheet [1], to avoid any pops/clicks, the outputs should be muted during input/output routing changes. [1] https://www.nxp.com/docs/en/data-sheet/SGTL5000.pdf Cc: stable@vger.kernel.org Fixes:9b34e6cc3b("ASoC: Add Freescale SGTL5000 codec support") Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> Reviewed-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com> Link: https://lore.kernel.org/r/20190719100524.23300-3-oleksandr.suvorov@toradex.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.