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ASoC: imx-ssi: Switch to SPDX identifier

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Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Andra Danciu <andradanciu1997@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Andra Danciu 2019-04-05 14:50:00 +03:00 committed by Mark Brown
parent 58dbd1015d
commit bdc16b5748
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GPG Key ID: 24D68B725D5487D0
2 changed files with 26 additions and 37 deletions
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57
sound/soc/fsl/imx-ssi.c
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@ -1,35 +1,28 @@
/*
* imx-ssi.c -- ALSA Soc Audio Layer
*
* Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
*
* This code is based on code copyrighted by Freescale,
* Liam Girdwood, Javier Martin and probably others.
*
* 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.
*
*
* The i.MX SSI core has some nasty limitations in AC97 mode. While most
* sane processor vendors have a FIFO per AC97 slot, the i.MX has only
* one FIFO which combines all valid receive slots. We cannot even select
* which slots we want to receive. The WM9712 with which this driver
* was developed with always sends GPIO status data in slot 12 which
* we receive in our (PCM-) data stream. The only chance we have is to
* manually skip this data in the FIQ handler. With sampling rates different
* from 48000Hz not every frame has valid receive data, so the ratio
* between pcm data and GPIO status data changes. Our FIQ handler is not
* able to handle this, hence this driver only works with 48000Hz sampling
* rate.
* Reading and writing AC97 registers is another challenge. The core
* provides us status bits when the read register is updated with *another*
* value. When we read the same register two times (and the register still
* contains the same value) these status bits are not set. We work
* around this by not polling these bits but only wait a fixed delay.
*
*/
// SPDX-License-Identifier: GPL-2.0+
//
// imx-ssi.c -- ALSA Soc Audio Layer
//
// Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
//
// This code is based on code copyrighted by Freescale,
// Liam Girdwood, Javier Martin and probably others.
//
// The i.MX SSI core has some nasty limitations in AC97 mode. While most
// sane processor vendors have a FIFO per AC97 slot, the i.MX has only
// one FIFO which combines all valid receive slots. We cannot even select
// which slots we want to receive. The WM9712 with which this driver
// was developed with always sends GPIO status data in slot 12 which
// we receive in our (PCM-) data stream. The only chance we have is to
// manually skip this data in the FIQ handler. With sampling rates different
// from 48000Hz not every frame has valid receive data, so the ratio
// between pcm data and GPIO status data changes. Our FIQ handler is not
// able to handle this, hence this driver only works with 48000Hz sampling
// rate.
// Reading and writing AC97 registers is another challenge. The core
// provides us status bits when the read register is updated with *another*
// value. When we read the same register two times (and the register still
// contains the same value) these status bits are not set. We work
// around this by not polling these bits but only wait a fixed delay.
#include <linux/clk.h>
#include <linux/delay.h>

6
sound/soc/fsl/imx-ssi.h
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@ -1,8 +1,4 @@
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _IMX_SSI_H
#define _IMX_SSI_H