linux_dsm_epyc7002/sound/soc/atmel/atmel_ssc_dai.h
Peter Rosin b6d6c6e95f ASoC: atmel_ssc_dai: Allow more rates
When the SSC acts as BCK master, use a ratnum rule to limit
the rate instead of only doing the standard rates. When the SSC
acts as BCK slave, allow any BCK frequency up to the SSC master
clock, divided by either of 2, 3 or 6.

Put a cap at 384kHz. Who's /ever/ going to need more than that?

The divider of 2, 3 or 6 is selected based on the Serial Clock Ratio
Considerations section from the SSC documentation:

    The Transmitter and the Receiver can be programmed to operate
    with the clock signals provided on either the TK or RK pins.
    This allows the SSC to support many slave-mode data transfers.
    In this case, the maximum clock speed allowed on the RK pin is:
    - Peripheral clock divided by 2 if Receiver Frame Synchro is input
    - Peripheral clock divided by 3 if Receiver Frame Synchro is output
    In addition, the maximum clock speed allowed on the TK pin is:
    - Peripheral clock divided by 6 if Transmit Frame Synchro is input
    - Peripheral clock divided by 2 if Transmit Frame Synchro is output

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-02-10 15:12:41 +08:00

125 lines
3.2 KiB
C

/*
* atmel_ssc_dai.h - ALSA SSC interface for the Atmel SoC
*
* Copyright (C) 2005 SAN People
* Copyright (C) 2008 Atmel
*
* Author: Sedji Gaouaou <sedji.gaouaou@atmel.com>
* ATMEL CORP.
*
* Based on at91-ssc.c by
* Frank Mandarino <fmandarino@endrelia.com>
* Based on pxa2xx Platform drivers by
* Liam Girdwood <lrg@slimlogic.co.uk>
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _ATMEL_SSC_DAI_H
#define _ATMEL_SSC_DAI_H
#include <linux/types.h>
#include <linux/atmel-ssc.h>
#include "atmel-pcm.h"
/* SSC system clock ids */
#define ATMEL_SYSCLK_MCK 0 /* SSC uses AT91 MCK as system clock */
/* SSC divider ids */
#define ATMEL_SSC_CMR_DIV 0 /* MCK divider for BCLK */
#define ATMEL_SSC_TCMR_PERIOD 1 /* BCLK divider for transmit FS */
#define ATMEL_SSC_RCMR_PERIOD 2 /* BCLK divider for receive FS */
/*
* SSC direction masks
*/
#define SSC_DIR_MASK_UNUSED 0
#define SSC_DIR_MASK_PLAYBACK 1
#define SSC_DIR_MASK_CAPTURE 2
/*
* SSC register values that Atmel left out of <linux/atmel-ssc.h>. These
* are expected to be used with SSC_BF
*/
/* START bit field values */
#define SSC_START_CONTINUOUS 0
#define SSC_START_TX_RX 1
#define SSC_START_LOW_RF 2
#define SSC_START_HIGH_RF 3
#define SSC_START_FALLING_RF 4
#define SSC_START_RISING_RF 5
#define SSC_START_LEVEL_RF 6
#define SSC_START_EDGE_RF 7
#define SSS_START_COMPARE_0 8
/* CKI bit field values */
#define SSC_CKI_FALLING 0
#define SSC_CKI_RISING 1
/* CKO bit field values */
#define SSC_CKO_NONE 0
#define SSC_CKO_CONTINUOUS 1
#define SSC_CKO_TRANSFER 2
/* CKS bit field values */
#define SSC_CKS_DIV 0
#define SSC_CKS_CLOCK 1
#define SSC_CKS_PIN 2
/* FSEDGE bit field values */
#define SSC_FSEDGE_POSITIVE 0
#define SSC_FSEDGE_NEGATIVE 1
/* FSOS bit field values */
#define SSC_FSOS_NONE 0
#define SSC_FSOS_NEGATIVE 1
#define SSC_FSOS_POSITIVE 2
#define SSC_FSOS_LOW 3
#define SSC_FSOS_HIGH 4
#define SSC_FSOS_TOGGLE 5
#define START_DELAY 1
struct atmel_ssc_state {
u32 ssc_cmr;
u32 ssc_rcmr;
u32 ssc_rfmr;
u32 ssc_tcmr;
u32 ssc_tfmr;
u32 ssc_sr;
u32 ssc_imr;
};
struct atmel_ssc_info {
char *name;
struct ssc_device *ssc;
spinlock_t lock; /* lock for dir_mask */
unsigned short dir_mask; /* 0=unused, 1=playback, 2=capture */
unsigned short initialized; /* true if SSC has been initialized */
unsigned short daifmt;
unsigned short cmr_div;
unsigned short tcmr_period;
unsigned short rcmr_period;
struct atmel_pcm_dma_params *dma_params[2];
struct atmel_ssc_state ssc_state;
unsigned long mck_rate;
};
int atmel_ssc_set_audio(int ssc_id);
void atmel_ssc_put_audio(int ssc_id);
#endif /* _AT91_SSC_DAI_H */