[alsa-devel] [PATCH 3/4] ESI W192M: Add sampling rate control.

[Takashi Iwai]

At Sat,  5 Oct 2013 15:41:04 +0200,
klem.dev at gmail.com wrote:
> 
> From: Clement Guedez <klem.dev at gmail.com>
> 
> Add sampling rate control for adc/dac in  Ego Sys Waveterminal 192M.
> 
> Signed-off-by: Clement Guedez <klem.dev at gmail.com>
> ---
>  sound/pci/ice1712/wtm.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)
> 
> diff --git a/sound/pci/ice1712/wtm.c b/sound/pci/ice1712/wtm.c
> index d559916..cf2b6a5 100644
> --- a/sound/pci/ice1712/wtm.c
> +++ b/sound/pci/ice1712/wtm.c
> @@ -29,6 +29,7 @@
>  #include <linux/interrupt.h>
>  #include <linux/init.h>
>  #include <sound/core.h>
> +#include <linux/slab.h>
>  #include <sound/tlv.h>
>  
>  #include "ice1712.h"
> @@ -69,6 +70,37 @@ static inline unsigned char stac9460_2_get(struct snd_ice1712 *ice, int reg)
>  /*
>   *	DAC mute control
>   */
> +static void stac9460_dac_mute_all(struct snd_ice1712 *ice, unsigned char mute,
> +				  unsigned char *change)
> +{
> +	unsigned char new, old;
> +	int idx;
> +
> +	/*stac9460 1*/
> +	for (idx = 0; idx < 7; idx++) {
> +		if (change[idx]) {
> +			old = stac9460_get(ice, idx);
> +			new = (~mute << 7 & 0x80) | (old & ~0x80);
> +			change[idx] = (new != old);
> +			if (change[idx])
> +				stac9460_put(ice, idx, new);
> +		}
> +	}
> +
> +	/*stac9460 2*/
> +	for (idx = 0; idx < 3; idx++) {
> +		if (change[idx + 7]) {
> +			old = stac9460_2_get(ice, idx);
> +			new = (~mute << 7 & 0x80) | (old & ~0x80);
> +			change[idx + 7] = (new != old);
> +			if (change[idx + 7])
> +				stac9460_2_put(ice, idx, new);
> +		}
> +	}

This code can be a bit more simplified...


> +}
> +
> +
> +
>  #define stac9460_dac_mute_info		snd_ctl_boolean_mono_info
>  
>  static int stac9460_dac_mute_get(struct snd_kcontrol *kcontrol,
> @@ -97,10 +129,13 @@ static int stac9460_dac_mute_put(struct snd_kcontrol *kcontrol,
>  				struct snd_ctl_elem_value *ucontrol)
>  {
>  	struct snd_ice1712 *ice = snd_kcontrol_chip(kcontrol);
> +	struct mutex *mute_mutex = ice->spec;

Define a new struct just containing a mutex, e.g.

	struct wtm_spec {
		struct mutex mute_mutex;
	};

This can be extended easily if anything new would be needed later.

>  	unsigned char new, old;
>  	int id, idx;
>  	int change;
>  
> +	mutex_lock(mute_mutex);
> +
>  	if (kcontrol->private_value) {
>  		idx = STAC946X_MASTER_VOLUME;
>  		old = stac9460_get(ice, idx);
> @@ -128,6 +163,9 @@ static int stac9460_dac_mute_put(struct snd_kcontrol *kcontrol,
>  				stac9460_2_put(ice, idx - 6, new);
>  		}
>  	}
> +
> +	mutex_unlock(mute_mutex);
> +
>  	return change;
>  }
>  
> @@ -381,6 +419,41 @@ static int stac9460_mic_sw_put(struct snd_kcontrol *kcontrol,
>  	return change;
>  }
>  
> +/*
> + * Handler for setting correct codec rate - called when rate change is detected
> + */
> +static void stac9460_set_rate_val(struct snd_ice1712 *ice, unsigned int rate)
> +{
> +	unsigned char old, new;
> +	unsigned char changed[10];

It's easier to use a bit flag instead of char[10].

> +	struct mutex *mute_mutex = ice->spec;
> +
> +	if (rate == 0)  /* no hint - S/PDIF input is master, simply return */
> +		return;
> +	else if (rate <= 48000)
> +		new = 0x08;     /* 256x, base rate mode */
> +	else if (rate <= 96000)
> +		new = 0x11;     /* 256x, mid rate mode */
> +	else
> +		new = 0x12;     /* 128x, high rate mode */
> +	old = stac9460_get(ice, STAC946X_MASTER_CLOCKING);
> +	if (old == new)
> +		return;
> +	/* change detected, setting master clock, muting first */
> +	/* due to possible conflicts with mute controls - mutexing */
> +	mutex_lock(mute_mutex);
> +	/* we have to remember current mute status for each DAC */
> +	stac9460_dac_mute_all(ice, 0, changed);

You didn't initialize changed[]?  In your logic, it must be set to all
1 at first.

> +	/*printk(KERN_DEBUG "Rate change: %d, new MC: 0x%02x\n", rate, new);*/
> +	stac9460_put(ice, STAC946X_MASTER_CLOCKING, new);
> +	udelay(10);
> +	/* unmuting - only originally unmuted dacs -
> +	* i.e. those changed when muting */
> +	stac9460_dac_mute_all(ice, 1, changed);
> +	mutex_unlock(mute_mutex);
> +}
> +
> +
>  
>  static const DECLARE_TLV_DB_SCALE(db_scale_dac, -19125, 75, 0);
>  static const DECLARE_TLV_DB_SCALE(db_scale_adc, 0, 150, 0);
> @@ -479,9 +552,11 @@ static int wtm_init(struct snd_ice1712 *ice)
>  {
>  	static unsigned short stac_inits_wtm[] = {
>  		STAC946X_RESET, 0,
> +		STAC946X_MASTER_CLOCKING, 0x11,
>  		(unsigned short)-1
>  	};
>  	unsigned short *p;
> +	struct mutex *mute_mutex;
>  
>  	/*WTM 192M*/
>  	ice->num_total_dacs = 8;
> @@ -489,12 +564,20 @@ static int wtm_init(struct snd_ice1712 *ice)
>  	ice->force_rdma1 = 1;
>  	ice->vt1720 = 0;  /* ice1724, e.g. 23 GPIOs */
>  
> +	mute_mutex = kzalloc(sizeof(*mute_mutex), GFP_KERNEL);
> +	if (!mute_mutex)
> +		return -ENOMEM;
> +	ice->spec = mute_mutex;
> +	mutex_init(mute_mutex);
> +
> +
>  	/*initialize codec*/
>  	p = stac_inits_wtm;
>  	for (; *p != (unsigned short)-1; p += 2) {
>  		stac9460_put(ice, p[0], p[1]);
>  		stac9460_2_put(ice, p[0], p[1]);
>  	}
> +	ice->gpio.set_pro_rate = stac9460_set_rate_val;
>  	return 0;
>  }



thanks,

Takashi