sb_ess.c

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#undef FKS_LOGGING
#undef FKS_TEST

/*
 * tabs should be 4 spaces, in vi(m): set tabstop=4
 *
 * TODO: 	consistency speed calculations!!
 *			cleanup!
 * ????:	Did I break MIDI support?
 *
 * History:
 *
 * Rolf Fokkens	 (Dec 20 1998):	ES188x recording level support on a per
 * [e-mail]			input basis.
 *				 (Dec 24 1998):	Recognition of ES1788, ES1887, ES1888,
 *								ES1868, ES1869 and ES1878. Could be used for
 *								specific handling in the future. All except
 *								ES1887 and ES1888 and ES688 are handled like
 *								ES1688.
 *				 (Dec 27 1998):	RECLEV for all (?) ES1688+ chips. ES188x now
 *								have the "Dec 20" support + RECLEV
 *				 (Jan  2 1999):	Preparation for Full Duplex. This means
 *								Audio 2 is now used for playback when dma16
 *								is specified. The next step would be to use
 *								Audio 1 and Audio 2 at the same time.
 *				 (Jan  9 1999):	Put all ESS stuff into sb_ess.[ch], this
 *								includes both the ESS stuff that has been in
 *								sb_*[ch] before I touched it and the ESS support
 *								I added later
 *				 (Jan 23 1999):	Full Duplex seems to work. I wrote a small
 *								test proggy which works OK. Haven't found
 *								any applications to test it though. So why did
 *								I bother to create it anyway?? :) Just for
 *								fun.
 *				 (May  2 1999):	I tried to be too smart by "introducing"
 *								ess_calc_best_speed (). The idea was that two
 *								dividers could be used to setup a samplerate,
 *								ess_calc_best_speed () would choose the best.
 *								This works for playback, but results in
 *								recording problems for high samplerates. I
 *								fixed this by removing ess_calc_best_speed ()
 *								and just doing what the documentation says. 
 * Andy Sloane   (Jun  4 1999): Stole some code from ALSA to fix the playback
 * [e-mail]		speed on ES1869, ES1879, ES1887, and ES1888.
 * 								1879's were previously ignored by this driver;
 * 								added (untested) support for those.
 * Cvetan Ivanov (Oct 27 1999): Fixed ess_dsp_init to call ess_set_dma_hw for
 * [e-mail]					_ALL_ ESS models, not only ES1887
 *
 * This files contains ESS chip specifics. It's based on the existing ESS
 * handling as it resided in sb_common.c, sb_mixer.c and sb_audio.c. This
 * file adds features like:
 * - Chip Identification (as shown in /proc/sound)
 * - RECLEV support for ES1688 and later
 * - 6 bits playback level support chips later than ES1688
 * - Recording level support on a per-device basis for ES1887
 * - Full-Duplex for ES1887
 *
 * Full duplex is enabled by specifying dma16. While the normal dma must
 * be one of 0, 1 or 3, dma16 can be one of 0, 1, 3 or 5. DMA 5 is a 16 bit
 * DMA channel, while the others are 8 bit..
 *
 * ESS detection isn't full proof (yet). If it fails an additional module
 * parameter esstype can be specified to be one of the following:
 * -1, 0, 688, 1688, 1868, 1869, 1788, 1887, 1888
 * -1 means: mimic 2.0 behaviour, 
 *  0 means: auto detect.
 *   others: explicitly specify chip
 * -1 is default, cause auto detect still doesn't work.
 */

/*
 * About the documentation
 *
 * I don't know if the chips all are OK, but the documentation is buggy. 'cause
 * I don't have all the cips myself, there's a lot I cannot verify. I'll try to
 * keep track of my latest insights about his here. If you have additional info,
 * please enlighten me ([e-mail])!
 *
 * I had the impression that ES1688 also has 6 bit master volume control. The
 * documentation about ES1888 (rev C, october '95) claims that ES1888 has
 * the following features ES1688 doesn't have:
 * - 6 bit master volume
 * - Full Duplex
 * So ES1688 apparently doesn't have 6 bit master volume control, but the
 * ES1688 does have RECLEV control. Makes me wonder: does ES688 have it too?
 * Without RECLEV ES688 won't be much fun I guess.
 *
 * From the ES1888 (rev C, october '95) documentation I got the impression
 * that registers 0x68 to 0x6e don't exist which means: no recording volume
 * controls. To my surprise the ES888 documentation (1/14/96) claims that
 * ES888 does have these record mixer registers, but that ES1888 doesn't have
 * 0x69 and 0x6b. So the rest should be there.
 *
 * I'm trying to get ES1887 Full Duplex. Audio 2 is playback only, while Audio 2
 * is both record and playback. I think I should use Audio 2 for all playback.
 *
 * The documentation is an adventure: it's close but not fully accurate. I
 * found out that after a reset some registers are *NOT* reset, though the
 * docs say the would be. Interresting ones are 0x7f, 0x7d and 0x7a. They are
 * related to the Audio 2 channel. I also was suprised about the consequenses
 * of writing 0x00 to 0x7f (which should be done by reset): The ES1887 moves
 * into ES1888 mode. This means that it claims IRQ 11, which happens to be my
 * ISDN adapter. Needless to say it no longer worked. I now understand why
 * after rebooting 0x7f already was 0x05, the value of my choice: the BIOS
 * did it.
 *
 * Oh, and this is another trap: in ES1887 docs mixer register 0x70 is decribed
 * as if it's exactly the same as register 0xa1. This is *NOT* true. The
 * description of 0x70 in ES1869 docs is accurate however.
 * Well, the assumption about ES1869 was wrong: register 0x70 is very much
 * like register 0xa1, except that bit 7 is allways 1, whatever you want
 * it to be.
 *
 * When using audio 2 mixer register 0x72 seems te be meaningless. Only 0xa2
 * has effect.
 *
 * Software reset not being able to reset all registers is great! Especially
 * the fact that register 0x78 isn't reset is great when you wanna change back
 * to single dma operation (simplex): audio 2 is still operation, and uses the
 * same dma as audio 1: your ess changes into a funny echo machine.
 *
 * Received the new that ES1688 is detected as a ES1788. Did some thinking:
 * the ES1887 detection scheme suggests in step 2 to try if bit 3 of register
 * 0x64 can be changed. This is inaccurate, first I inverted the * check: "If
 * can be modified, it's a 1688", which lead to a correct detection
 * of my ES1887. It resulted however in bad detection of 1688 (reported by mail)
 * and 1868 (if no PnP detection first): they result in a 1788 being detected.
 * I don't have docs on 1688, but I do have docs on 1868: The documentation is
 * probably inaccurate in the fact that I should check bit 2, not bit 3. This
 * is what I do now.
 */

/*
 * About recognition of ESS chips
 *
 * The distinction of ES688, ES1688, ES1788, ES1887 and ES1888 is described in
 * a (preliminary ??) datasheet on ES1887. It's aim is to identify ES1887, but
 * during detection the text claims that "this chip may be ..." when a step
 * fails. This scheme is used to distinct between the above chips.
 * It appears however that some PnP chips like ES1868 are recognized as ES1788
 * by the ES1887 detection scheme. These PnP chips can be detected in another
 * way however: ES1868, ES1869 and ES1878 can be recognized (full proof I think)
 * by repeatedly reading mixer register 0x40. This is done by ess_identify in
 * sb_common.c.
 * This results in the following detection steps:
 * - distinct between ES688 and ES1688+ (as always done in this driver)
 *   if ES688 we're ready
 * - try to detect ES1868, ES1869 or ES1878
 *   if successful we're ready
 * - try to detect ES1888, ES1887 or ES1788
 *   if successful we're ready
 * - Dunno. Must be 1688. Will do in general
 *
 * About RECLEV support:
 *
 * The existing ES1688 support didn't take care of the ES1688+ recording
 * levels very well. Whenever a device was selected (recmask) for recording
 * it's recording level was loud, and it couldn't be changed. The fact that
 * internal register 0xb4 could take care of RECLEV, didn't work meaning until
 * it's value was restored every time the chip was reset; this reset the
 * value of 0xb4 too. I guess that's what 4front also had (have?) trouble with.
 *
 * About ES1887 support:
 *
 * The ES1887 has separate registers to control the recording levels, for all
 * inputs. The ES1887 specific software makes these levels the same as their
 * corresponding playback levels, unless recmask says they aren't recorded. In
 * the latter case the recording volumes are 0.
 * Now recording levels of inputs can be controlled, by changing the playback
 * levels. Futhermore several devices can be recorded together (which is not
 * possible with the ES1688.
 * Besides the separate recording level control for each input, the common
 * recordig level can also be controlled by RECLEV as described above.
 *
 * Not only ES1887 have this recording mixer. I know the following from the
 * documentation:
 * ES688	no
 * ES1688	no
 * ES1868	no
 * ES1869	yes
 * ES1878	no
 * ES1879	yes
 * ES1888	no/yes	Contradicting documentation; most recent: yes
 * ES1946	yes		This is a PCI chip; not handled by this driver
 */

#include <linux/delay.h>

#include "sound_config.h"
#include "sb_mixer.h"
#include "sb.h"

#include "sb_ess.h"

#define ESSTYPE_LIKE20	-1		/* Mimic 2.0 behaviour					*/
#define ESSTYPE_DETECT	0		/* Mimic 2.0 behaviour					*/

#define SUBMDL_ES1788	0x10	/* Subtype ES1788 for specific handling */
#define SUBMDL_ES1868	0x11	/* Subtype ES1868 for specific handling */
#define SUBMDL_ES1869	0x12	/* Subtype ES1869 for specific handling */
#define SUBMDL_ES1878	0x13	/* Subtype ES1878 for specific handling */
#define SUBMDL_ES1879	0x16    /* ES1879 was initially forgotten */
#define SUBMDL_ES1887	0x14	/* Subtype ES1887 for specific handling */
#define SUBMDL_ES1888	0x15	/* Subtype ES1888 for specific handling */

#define SB_CAP_ES18XX_RATE 0x100

#define ES1688_CLOCK1 795444 /* 128 - div */
#define ES1688_CLOCK2 397722 /* 256 - div */
#define ES18XX_CLOCK1 793800 /* 128 - div */
#define ES18XX_CLOCK2 768000 /* 256 - div */

#ifdef FKS_LOGGING
static void ess_show_mixerregs (sb_devc *devc);
#endif
static int ess_read (sb_devc * devc, unsigned char reg);
static int ess_write (sb_devc * devc, unsigned char reg, unsigned char data);
static void ess_chgmixer
	(sb_devc * devc, unsigned int reg, unsigned int mask, unsigned int val);

/****************************************************************************
 *																			*
 *									ESS audio								*
 *																			*
 ****************************************************************************/

struct ess_command {short cmd; short data;};

/*
 * Commands for initializing Audio 1 for input (record)
 */
static struct ess_command ess_i08m[] =		/* input 8 bit mono */
	{ {0xb7, 0x51}, {0xb7, 0xd0}, {-1, 0} };
static struct ess_command ess_i16m[] =		/* input 16 bit mono */
	{ {0xb7, 0x71}, {0xb7, 0xf4}, {-1, 0} };
static struct ess_command ess_i08s[] =		/* input 8 bit stereo */
	{ {0xb7, 0x51}, {0xb7, 0x98}, {-1, 0} };
static struct ess_command ess_i16s[] =		/* input 16 bit stereo */
	{ {0xb7, 0x71}, {0xb7, 0xbc}, {-1, 0} };

static struct ess_command *ess_inp_cmds[] =
	{ ess_i08m, ess_i16m, ess_i08s, ess_i16s };


/*
 * Commands for initializing Audio 1 for output (playback)
 */
static struct ess_command ess_o08m[] =		/* output 8 bit mono */
	{ {0xb6, 0x80}, {0xb7, 0x51}, {0xb7, 0xd0}, {-1, 0} };
static struct ess_command ess_o16m[] =		/* output 16 bit mono */
	{ {0xb6, 0x00}, {0xb7, 0x71}, {0xb7, 0xf4}, {-1, 0} };
static struct ess_command ess_o08s[] =		/* output 8 bit stereo */
	{ {0xb6, 0x80}, {0xb7, 0x51}, {0xb7, 0x98}, {-1, 0} };
static struct ess_command ess_o16s[] =		/* output 16 bit stereo */
	{ {0xb6, 0x00}, {0xb7, 0x71}, {0xb7, 0xbc}, {-1, 0} };

static struct ess_command *ess_out_cmds[] =
	{ ess_o08m, ess_o16m, ess_o08s, ess_o16s };

static void ess_exec_commands
	(sb_devc *devc, struct ess_command *cmdtab[])
{
	struct ess_command *cmd;

	cmd = cmdtab [ ((devc->channels != 1) << 1) + (devc->bits != AFMT_U8) ];

	while (cmd->cmd != -1) {
		ess_write (devc, cmd->cmd, cmd->data);
		cmd++;
	}
}

static void ess_change
	(sb_devc *devc, unsigned int reg, unsigned int mask, unsigned int val)
{
	int value;

	value = ess_read (devc, reg);
	value = (value & ~mask) | (val & mask);
	ess_write (devc, reg, value);
}

static void ess_set_output_parms
	(int dev, unsigned long buf, int nr_bytes, int intrflag)
{
	sb_devc *devc = audio_devs[dev]->devc;

	if (devc->duplex) {
		devc->trg_buf_16 = buf;
		devc->trg_bytes_16 = nr_bytes;
		devc->trg_intrflag_16 = intrflag;
		devc->irq_mode_16 = IMODE_OUTPUT;
	} else {
		devc->trg_buf = buf;
		devc->trg_bytes = nr_bytes;
		devc->trg_intrflag = intrflag;
		devc->irq_mode = IMODE_OUTPUT;
	}
}

static void ess_set_input_parms
	(int dev, unsigned long buf, int count, int intrflag)
{
	sb_devc *devc = audio_devs[dev]->devc;

	devc->trg_buf = buf;
	devc->trg_bytes = count;
	devc->trg_intrflag = intrflag;
	devc->irq_mode = IMODE_INPUT;
}

static int ess_calc_div (int clock, int revert, int *speedp, int *diffp)
{
	int divider;
	int speed, diff;
	int retval;

	speed   = *speedp;
	divider = (clock + speed / 2) / speed;
	retval  = revert - divider;
	if (retval > revert - 1) {
		retval  = revert - 1;
		divider = revert - retval;
	}
	/* This line is suggested. Must be wrong I think
	*speedp = (clock + divider / 2) / divider;
	So I chose the next one */

	*speedp	= clock / divider;
	diff	= speed - *speedp;
	if (diff < 0) diff =-diff;
	*diffp  = diff;

	return retval;
}

static int ess_calc_best_speed
	(int clock1, int rev1, int clock2, int rev2, int *divp, int *speedp)
{
	int speed1 = *speedp, speed2 = *speedp;
	int div1, div2;
	int diff1, diff2;
	int retval;

	div1 = ess_calc_div (clock1, rev1, &speed1, &diff1);
	div2 = ess_calc_div (clock2, rev2, &speed2, &diff2);

	if (diff1 < diff2) {
		*divp   = div1;
		*speedp = speed1;
		retval  = 1;
	} else {
		*divp   = div2;
		*speedp = speed2;
		retval  = 2;
	}

	return retval;
}

/*
 * Depending on the audiochannel ESS devices can
 * have different clock settings. These are made consistent for duplex
 * however.
 * callers of ess_speed only do an audionum suggestion, which means
 * input suggests 1, output suggests 2. This suggestion is only true
 * however when doing duplex.
 */
static void ess_common_speed (sb_devc *devc, int *speedp, int *divp)
{
	int diff = 0, div;

	if (devc->duplex) {
		/*
		 * The 0x80 is important for the first audio channel
		 */
		div = 0x80 | ess_calc_div (795500, 128, speedp, &diff);
	} else if(devc->caps & SB_CAP_ES18XX_RATE) {
		ess_calc_best_speed(ES18XX_CLOCK1, 128, ES18XX_CLOCK2, 256, 
						&div, speedp);
	} else {
		if (*speedp > 22000) {
			div = 0x80 | ess_calc_div (ES1688_CLOCK1, 256, speedp, &diff);
		} else {
			div = 0x00 | ess_calc_div (ES1688_CLOCK2, 128, speedp, &diff);
		}
	}
	*divp = div;
}

static void ess_speed (sb_devc *devc, int audionum)
{
	int speed;
	int div, div2;

	ess_common_speed (devc, &(devc->speed), &div);

#ifdef FKS_REG_LOGGING
printk (KERN_INFO "FKS: ess_speed (%d) b speed = %d, div=%x\n", audionum, devc->speed, div);
#endif

	/* Set filter roll-off to 90% of speed/2 */
	speed = (devc->speed * 9) / 20;

	div2 = 256 - 7160000 / (speed * 82);

	if (!devc->duplex) audionum = 1;

	if (audionum == 1) {
		/* Change behaviour of register A1 *
		sb_chg_mixer(devc, 0x71, 0x20, 0x20)
		* For ES1869 only??? */
		ess_write (devc, 0xa1, div);
		ess_write (devc, 0xa2, div2);
	} else {
		ess_setmixer (devc, 0x70, div);
		/*
		 * FKS: fascinating: 0x72 doesn't seem to work.
		 */
		ess_write (devc, 0xa2, div2);
		ess_setmixer (devc, 0x72, div2);
	}
}

static int ess_audio_prepare_for_input(int dev, int bsize, int bcount)
{
	sb_devc *devc = audio_devs[dev]->devc;

	ess_speed(devc, 1);

	sb_dsp_command(devc, DSP_CMD_SPKOFF);

	ess_write (devc, 0xb8, 0x0e);	/* Auto init DMA mode */
	ess_change (devc, 0xa8, 0x03, 3 - devc->channels);	/* Mono/stereo */
	ess_write (devc, 0xb9, 2);	/* Demand mode (4 bytes/DMA request) */

	ess_exec_commands (devc, ess_inp_cmds);

	ess_change (devc, 0xb1, 0xf0, 0x50);
	ess_change (devc, 0xb2, 0xf0, 0x50);

	devc->trigger_bits = 0;
	return 0;
}

static int ess_audio_prepare_for_output_audio1 (int dev, int bsize, int bcount)
{
	sb_devc *devc = audio_devs[dev]->devc;

	sb_dsp_reset(devc);
	ess_speed(devc, 1);
	ess_write (devc, 0xb8, 4);	/* Auto init DMA mode */
	ess_change (devc, 0xa8, 0x03, 3 - devc->channels);	/* Mono/stereo */
	ess_write (devc, 0xb9, 2);	/* Demand mode (4 bytes/request) */