[alsa-devel] [PATCH v4 02/10] ASoc: mxs: add mxs-saif driver

[Dong Aisheng]

2011/7/21 Liam Girdwood <lrg at ti.com>:
> On 20/07/11 04:41, Dong Aisheng wrote:
>> Signed-off-by: Dong Aisheng <b29396 at freescale.com>
>> Cc: Mark Brown <broonie at opensource.wolfsonmicro.com>
>> Cc: Liam Girdwood <lrg at ti.com>
>> Cc: Sascha Hauer <s.hauer at pengutronix.de>
>> Tested-by: Wolfram Sang <w.sang at pengutronix.de>
>> ---
>>  sound/soc/mxs/mxs-saif.c |  677 ++++++++++++++++++++++++++++++++++++++++++++++
>>  sound/soc/mxs/mxs-saif.h |  130 +++++++++
>>  2 files changed, 807 insertions(+), 0 deletions(-)
>>
>> diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c
>> new file mode 100644
>> index 0000000..0b3adae
>> --- /dev/null
>> +++ b/sound/soc/mxs/mxs-saif.c
>> @@ -0,0 +1,677 @@
>> +/*
>> + * Copyright 2011 Freescale Semiconductor, Inc.
>> + *
>> + * 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.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along
>> + * with this program; if not, write to the Free Software Foundation, Inc.,
>> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/dma-mapping.h>
>> +#include <linux/clk.h>
>> +#include <linux/delay.h>
>> +#include <sound/core.h>
>> +#include <sound/pcm.h>
>> +#include <sound/pcm_params.h>
>> +#include <sound/soc.h>
>> +#include <mach/dma.h>
>> +#include <asm/mach-types.h>
>> +#include <mach/hardware.h>
>> +#include <mach/mxs.h>
>> +
>> +#include "mxs-saif.h"
>> +
>> +static struct mxs_saif *mxs_saif[2];
>> +
>
> Is there any reason why this struct cant be part of your DAI private data ?

Yes, it is because we provide a interface mxs_saif_get_mclk for
machine driver to get the mclk if needed in a very early stage such as
probe.
And during that time, the machine driver will not be able to provide a
DAI as parameter
(card is still not registered).

+ * Get MCLK and set clock rate, then enable it
+ *
+ * This interface is used for codecs who are using MCLK provided
+ * by saif.
+ */
+int mxs_saif_get_mclk(unsigned int saif_id, unsigned int mclk,
+                                       unsigned int rate)

Regards
Dong Aisheng