rtd520.c 44.8 KB
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/*
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 * comedi/drivers/rtd520.c
 * Comedi driver for Real Time Devices (RTD) PCI4520/DM7520
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 2001 David A. Schleef <ds@schleef.org>
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
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/*
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 * Driver: rtd520
 * Description: Real Time Devices PCI4520/DM7520
 * Devices: (Real Time Devices) DM7520HR-1 [DM7520]
 *	    (Real Time Devices) DM7520HR-8 [DM7520]
 *	    (Real Time Devices) PCI4520 [PCI4520]
 *	    (Real Time Devices) PCI4520-8 [PCI4520]
 * Author: Dan Christian
 * Status: Works. Only tested on DM7520-8. Not SMP safe.
 *
 * Configuration options: not applicable, uses PCI auto config
 */
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/*
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 * Created by Dan Christian, NASA Ames Research Center.
 *
 * The PCI4520 is a PCI card. The DM7520 is a PC/104-plus card.
 * Both have:
 *   8/16 12 bit ADC with FIFO and channel gain table
 *   8 bits high speed digital out (for external MUX) (or 8 in or 8 out)
 *   8 bits high speed digital in with FIFO and interrupt on change (or 8 IO)
 *   2 12 bit DACs with FIFOs
 *   2 bits output
 *   2 bits input
 *   bus mastering DMA
 *   timers: ADC sample, pacer, burst, about, delay, DA1, DA2
 *   sample counter
 *   3 user timer/counters (8254)
 *   external interrupt
 *
 * The DM7520 has slightly fewer features (fewer gain steps).
 *
 * These boards can support external multiplexors and multi-board
 * synchronization, but this driver doesn't support that.
 *
 * Board docs: http://www.rtdusa.com/PC104/DM/analog%20IO/dm7520.htm
 * Data sheet: http://www.rtdusa.com/pdf/dm7520.pdf
 * Example source: http://www.rtdusa.com/examples/dm/dm7520.zip
 * Call them and ask for the register level manual.
 * PCI chip: http://www.plxtech.com/products/io/pci9080
 *
 * Notes:
 * This board is memory mapped. There is some IO stuff, but it isn't needed.
 *
 * I use a pretty loose naming style within the driver (rtd_blah).
 * All externally visible names should be rtd520_blah.
 * I use camelCase for structures (and inside them).
 * I may also use upper CamelCase for function names (old habit).
 *
 * This board is somewhat related to the RTD PCI4400 board.
 *
 * I borrowed heavily from the ni_mio_common, ni_atmio16d, mite, and
 * das1800, since they have the best documented code. Driver cb_pcidas64.c
 * uses the same DMA controller.
 *
 * As far as I can tell, the About interrupt doesn't work if Sample is
 * also enabled. It turns out that About really isn't needed, since
 * we always count down samples read.
 *
 * There was some timer/counter code, but it didn't follow the right API.
 */
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 * driver status:
 *
 * Analog-In supports instruction and command mode.
 *
 * With DMA, you can sample at 1.15Mhz with 70% idle on a 400Mhz K6-2
 * (single channel, 64K read buffer). I get random system lockups when
 * using DMA with ALI-15xx based systems. I haven't been able to test
 * any other chipsets. The lockups happen soon after the start of an
 * acquistion, not in the middle of a long run.
 *
 * Without DMA, you can do 620Khz sampling with 20% idle on a 400Mhz K6-2
 * (with a 256K read buffer).
 *
 * Digital-IO and Analog-Out only support instruction mode.
 */
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#include <linux/pci.h>
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#include <linux/delay.h>
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#include <linux/interrupt.h>
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#include "../comedidev.h"

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#include "comedi_fc.h"
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#include "plx9080.h"
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/*
 * Local Address Space 0 Offsets
 */
#define LAS0_USER_IO		0x0008	/* User I/O */
#define LAS0_ADC		0x0010	/* FIFO Status/Software A/D Start */
#define FS_DAC1_NOT_EMPTY	(1 << 0)	/* DAC1 FIFO not empty */
#define FS_DAC1_HEMPTY		(1 << 1)	/* DAC1 FIFO half empty */
#define FS_DAC1_NOT_FULL	(1 << 2)	/* DAC1 FIFO not full */
#define FS_DAC2_NOT_EMPTY	(1 << 4)	/* DAC2 FIFO not empty */
#define FS_DAC2_HEMPTY		(1 << 5)	/* DAC2 FIFO half empty */
#define FS_DAC2_NOT_FULL	(1 << 6)	/* DAC2 FIFO not full */
#define FS_ADC_NOT_EMPTY	(1 << 8)	/* ADC FIFO not empty */
#define FS_ADC_HEMPTY		(1 << 9)	/* ADC FIFO half empty */
#define FS_ADC_NOT_FULL		(1 << 10)	/* ADC FIFO not full */
#define FS_DIN_NOT_EMPTY	(1 << 12)	/* DIN FIFO not empty */
#define FS_DIN_HEMPTY		(1 << 13)	/* DIN FIFO half empty */
#define FS_DIN_NOT_FULL		(1 << 14)	/* DIN FIFO not full */
#define LAS0_DAC1		0x0014	/* Software D/A1 Update (w) */
#define LAS0_DAC2		0x0018	/* Software D/A2 Update (w) */
#define LAS0_DAC		0x0024	/* Software Simultaneous Update (w) */
#define LAS0_PACER		0x0028	/* Software Pacer Start/Stop */
#define LAS0_TIMER		0x002c	/* Timer Status/HDIN Software Trig. */
#define LAS0_IT			0x0030	/* Interrupt Status/Enable */
#define IRQM_ADC_FIFO_WRITE	(1 << 0)	/* ADC FIFO Write */
#define IRQM_CGT_RESET		(1 << 1)	/* Reset CGT */
#define IRQM_CGT_PAUSE		(1 << 3)	/* Pause CGT */
#define IRQM_ADC_ABOUT_CNT	(1 << 4)	/* About Counter out */
#define IRQM_ADC_DELAY_CNT	(1 << 5)	/* Delay Counter out */
#define IRQM_ADC_SAMPLE_CNT	(1 << 6)	/* ADC Sample Counter */
#define IRQM_DAC1_UCNT		(1 << 7)	/* DAC1 Update Counter */
#define IRQM_DAC2_UCNT		(1 << 8)	/* DAC2 Update Counter */
#define IRQM_UTC1		(1 << 9)	/* User TC1 out */
#define IRQM_UTC1_INV		(1 << 10)	/* User TC1 out, inverted */
#define IRQM_UTC2		(1 << 11)	/* User TC2 out */
#define IRQM_DIGITAL_IT		(1 << 12)	/* Digital Interrupt */
#define IRQM_EXTERNAL_IT	(1 << 13)	/* External Interrupt */
#define IRQM_ETRIG_RISING	(1 << 14)	/* Ext Trigger rising-edge */
#define IRQM_ETRIG_FALLING	(1 << 15)	/* Ext Trigger falling-edge */
#define LAS0_CLEAR		0x0034	/* Clear/Set Interrupt Clear Mask */
#define LAS0_OVERRUN		0x0038	/* Pending interrupts/Clear Overrun */
#define LAS0_PCLK		0x0040	/* Pacer Clock (24bit) */
#define LAS0_BCLK		0x0044	/* Burst Clock (10bit) */
#define LAS0_ADC_SCNT		0x0048	/* A/D Sample counter (10bit) */
#define LAS0_DAC1_UCNT		0x004c	/* D/A1 Update counter (10 bit) */
#define LAS0_DAC2_UCNT		0x0050	/* D/A2 Update counter (10 bit) */
#define LAS0_DCNT		0x0054	/* Delay counter (16 bit) */
#define LAS0_ACNT		0x0058	/* About counter (16 bit) */
#define LAS0_DAC_CLK		0x005c	/* DAC clock (16bit) */
#define LAS0_UTC0		0x0060	/* 8254 TC Counter 0 */
#define LAS0_UTC1		0x0064	/* 8254 TC Counter 1 */
#define LAS0_UTC2		0x0068	/* 8254 TC Counter 2 */
#define LAS0_UTC_CTRL		0x006c	/* 8254 TC Control */
#define LAS0_DIO0		0x0070	/* Digital I/O Port 0 */
#define LAS0_DIO1		0x0074	/* Digital I/O Port 1 */
#define LAS0_DIO0_CTRL		0x0078	/* Digital I/O Control */
#define LAS0_DIO_STATUS		0x007c	/* Digital I/O Status */
#define LAS0_BOARD_RESET	0x0100	/* Board reset */
#define LAS0_DMA0_SRC		0x0104	/* DMA 0 Sources select */
#define LAS0_DMA1_SRC		0x0108	/* DMA 1 Sources select */
#define LAS0_ADC_CONVERSION	0x010c	/* A/D Conversion Signal select */
#define LAS0_BURST_START	0x0110	/* Burst Clock Start Trigger select */
#define LAS0_PACER_START	0x0114	/* Pacer Clock Start Trigger select */
#define LAS0_PACER_STOP		0x0118	/* Pacer Clock Stop Trigger select */
#define LAS0_ACNT_STOP_ENABLE	0x011c	/* About Counter Stop Enable */
#define LAS0_PACER_REPEAT	0x0120	/* Pacer Start Trigger Mode select */
#define LAS0_DIN_START		0x0124	/* HiSpd DI Sampling Signal select */
#define LAS0_DIN_FIFO_CLEAR	0x0128	/* Digital Input FIFO Clear */
#define LAS0_ADC_FIFO_CLEAR	0x012c	/* A/D FIFO Clear */
#define LAS0_CGT_WRITE		0x0130	/* Channel Gain Table Write */
#define LAS0_CGL_WRITE		0x0134	/* Channel Gain Latch Write */
#define LAS0_CG_DATA		0x0138	/* Digital Table Write */
#define LAS0_CGT_ENABLE		0x013c	/* Channel Gain Table Enable */
#define LAS0_CG_ENABLE		0x0140	/* Digital Table Enable */
#define LAS0_CGT_PAUSE		0x0144	/* Table Pause Enable */
#define LAS0_CGT_RESET		0x0148	/* Reset Channel Gain Table */
#define LAS0_CGT_CLEAR		0x014c	/* Clear Channel Gain Table */
#define LAS0_DAC1_CTRL		0x0150	/* D/A1 output type/range */
#define LAS0_DAC1_SRC		0x0154	/* D/A1 update source */
#define LAS0_DAC1_CYCLE		0x0158	/* D/A1 cycle mode */
#define LAS0_DAC1_RESET		0x015c	/* D/A1 FIFO reset */
#define LAS0_DAC1_FIFO_CLEAR	0x0160	/* D/A1 FIFO clear */
#define LAS0_DAC2_CTRL		0x0164	/* D/A2 output type/range */
#define LAS0_DAC2_SRC		0x0168	/* D/A2 update source */
#define LAS0_DAC2_CYCLE		0x016c	/* D/A2 cycle mode */
#define LAS0_DAC2_RESET		0x0170	/* D/A2 FIFO reset */
#define LAS0_DAC2_FIFO_CLEAR	0x0174	/* D/A2 FIFO clear */
#define LAS0_ADC_SCNT_SRC	0x0178	/* A/D Sample Counter Source select */
#define LAS0_PACER_SELECT	0x0180	/* Pacer Clock select */
#define LAS0_SBUS0_SRC		0x0184	/* SyncBus 0 Source select */
#define LAS0_SBUS0_ENABLE	0x0188	/* SyncBus 0 enable */
#define LAS0_SBUS1_SRC		0x018c	/* SyncBus 1 Source select */
#define LAS0_SBUS1_ENABLE	0x0190	/* SyncBus 1 enable */
#define LAS0_SBUS2_SRC		0x0198	/* SyncBus 2 Source select */
#define LAS0_SBUS2_ENABLE	0x019c	/* SyncBus 2 enable */
#define LAS0_ETRG_POLARITY	0x01a4	/* Ext. Trigger polarity select */
#define LAS0_EINT_POLARITY	0x01a8	/* Ext. Interrupt polarity select */
#define LAS0_UTC0_CLOCK		0x01ac	/* UTC0 Clock select */
#define LAS0_UTC0_GATE		0x01b0	/* UTC0 Gate select */
#define LAS0_UTC1_CLOCK		0x01b4	/* UTC1 Clock select */
#define LAS0_UTC1_GATE		0x01b8	/* UTC1 Gate select */
#define LAS0_UTC2_CLOCK		0x01bc	/* UTC2 Clock select */
#define LAS0_UTC2_GATE		0x01c0	/* UTC2 Gate select */
#define LAS0_UOUT0_SELECT	0x01c4	/* User Output 0 source select */
#define LAS0_UOUT1_SELECT	0x01c8	/* User Output 1 source select */
#define LAS0_DMA0_RESET		0x01cc	/* DMA0 Request state machine reset */
#define LAS0_DMA1_RESET		0x01d0	/* DMA1 Request state machine reset */

/*
 * Local Address Space 1 Offsets
 */
#define LAS1_ADC_FIFO		0x0000	/* A/D FIFO (16bit) */
#define LAS1_HDIO_FIFO		0x0004	/* HiSpd DI FIFO (16bit) */
#define LAS1_DAC1_FIFO		0x0008	/* D/A1 FIFO (16bit) */
#define LAS1_DAC2_FIFO		0x000c	/* D/A2 FIFO (16bit) */

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/*======================================================================
  Driver specific stuff (tunable)
======================================================================*/

/* We really only need 2 buffers.  More than that means being much
   smarter about knowing which ones are full. */
#define DMA_CHAIN_COUNT 2	/* max DMA segments/buffers in a ring (min 2) */

/* Target period for periodic transfers.  This sets the user read latency. */
/* Note: There are certain rates where we give this up and transfer 1/2 FIFO */
/* If this is too low, efficiency is poor */
#define TRANS_TARGET_PERIOD 10000000	/* 10 ms (in nanoseconds) */

/* Set a practical limit on how long a list to support (affects memory use) */
/* The board support a channel list up to the FIFO length (1K or 8K) */
#define RTD_MAX_CHANLIST	128	/* max channel list that we allow */

/* tuning for ai/ao instruction done polling */
#ifdef FAST_SPIN
#define WAIT_QUIETLY		/* as nothing, spin on done bit */
#define RTD_ADC_TIMEOUT	66000	/* 2 msec at 33mhz bus rate */
#define RTD_DAC_TIMEOUT	66000
#define RTD_DMA_TIMEOUT	33000	/* 1 msec */
#else
/* by delaying, power and electrical noise are reduced somewhat */
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#define WAIT_QUIETLY	udelay(1)
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#define RTD_ADC_TIMEOUT	2000	/* in usec */
#define RTD_DAC_TIMEOUT	2000	/* in usec */
#define RTD_DMA_TIMEOUT	1000	/* in usec */
#endif

/*======================================================================
  Board specific stuff
======================================================================*/

#define RTD_CLOCK_RATE	8000000	/* 8Mhz onboard clock */
#define RTD_CLOCK_BASE	125	/* clock period in ns */

/* Note: these speed are slower than the spec, but fit the counter resolution*/
#define RTD_MAX_SPEED	1625	/* when sampling, in nanoseconds */
/* max speed if we don't have to wait for settling */
#define RTD_MAX_SPEED_1	875	/* if single channel, in nanoseconds */

#define RTD_MIN_SPEED	2097151875	/* (24bit counter) in nanoseconds */
/* min speed when only 1 channel (no burst counter) */
#define RTD_MIN_SPEED_1	5000000	/* 200Hz, in nanoseconds */

/* Setup continuous ring of 1/2 FIFO transfers.  See RTD manual p91 */
#define DMA_MODE_BITS (\
		       PLX_LOCAL_BUS_16_WIDE_BITS \
		       | PLX_DMA_EN_READYIN_BIT \
		       | PLX_DMA_LOCAL_BURST_EN_BIT \
		       | PLX_EN_CHAIN_BIT \
		       | PLX_DMA_INTR_PCI_BIT \
		       | PLX_LOCAL_ADDR_CONST_BIT \
		       | PLX_DEMAND_MODE_BIT)

#define DMA_TRANSFER_BITS (\
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/* descriptors in PCI memory*/  PLX_DESC_IN_PCI_BIT \
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/* interrupt at end of block */ | PLX_INTR_TERM_COUNT \
/* from board to PCI */		| PLX_XFER_LOCAL_TO_PCI)

/*======================================================================
  Comedi specific stuff
======================================================================*/

/*
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 * The board has 3 input modes and the gains of 1,2,4,...32 (, 64, 128)
 */
static const struct comedi_lrange rtd_ai_7520_range = {
	18, {
		/* +-5V input range gain steps */
		BIP_RANGE(5.0),
		BIP_RANGE(5.0 / 2),
		BIP_RANGE(5.0 / 4),
		BIP_RANGE(5.0 / 8),
		BIP_RANGE(5.0 / 16),
		BIP_RANGE(5.0 / 32),
		/* +-10V input range gain steps */
		BIP_RANGE(10.0),
		BIP_RANGE(10.0 / 2),
		BIP_RANGE(10.0 / 4),
		BIP_RANGE(10.0 / 8),
		BIP_RANGE(10.0 / 16),
		BIP_RANGE(10.0 / 32),
		/* +10V input range gain steps */
		UNI_RANGE(10.0),
		UNI_RANGE(10.0 / 2),
		UNI_RANGE(10.0 / 4),
		UNI_RANGE(10.0 / 8),
		UNI_RANGE(10.0 / 16),
		UNI_RANGE(10.0 / 32),
	}
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};

/* PCI4520 has two more gains (6 more entries) */
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static const struct comedi_lrange rtd_ai_4520_range = {
	24, {
		/* +-5V input range gain steps */
		BIP_RANGE(5.0),
		BIP_RANGE(5.0 / 2),
		BIP_RANGE(5.0 / 4),
		BIP_RANGE(5.0 / 8),
		BIP_RANGE(5.0 / 16),
		BIP_RANGE(5.0 / 32),
		BIP_RANGE(5.0 / 64),
		BIP_RANGE(5.0 / 128),
		/* +-10V input range gain steps */
		BIP_RANGE(10.0),
		BIP_RANGE(10.0 / 2),
		BIP_RANGE(10.0 / 4),
		BIP_RANGE(10.0 / 8),
		BIP_RANGE(10.0 / 16),
		BIP_RANGE(10.0 / 32),
		BIP_RANGE(10.0 / 64),
		BIP_RANGE(10.0 / 128),
		/* +10V input range gain steps */
		UNI_RANGE(10.0),
		UNI_RANGE(10.0 / 2),
		UNI_RANGE(10.0 / 4),
		UNI_RANGE(10.0 / 8),
		UNI_RANGE(10.0 / 16),
		UNI_RANGE(10.0 / 32),
		UNI_RANGE(10.0 / 64),
		UNI_RANGE(10.0 / 128),
	}
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};

/* Table order matches range values */
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static const struct comedi_lrange rtd_ao_range = {
	4, {
		UNI_RANGE(5),
		UNI_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(10),
	}
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};

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enum rtd_boardid {
	BOARD_DM7520,
	BOARD_PCI4520,
};

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struct rtdBoard {
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	const char *name;
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	int range10Start;	/* start of +-10V range */
	int rangeUniStart;	/* start of +10V range */
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	const struct comedi_lrange *ai_range;
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};
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static const struct rtdBoard rtd520Boards[] = {
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	[BOARD_DM7520] = {
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		.name		= "DM7520",
		.range10Start	= 6,
		.rangeUniStart	= 12,
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		.ai_range	= &rtd_ai_7520_range,
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	},
	[BOARD_PCI4520] = {
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		.name		= "PCI4520",
		.range10Start	= 8,
		.rangeUniStart	= 16,
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		.ai_range	= &rtd_ai_4520_range,
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	},
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};

/*
   This structure is for data unique to this hardware driver.
   This is also unique for each board in the system.
*/
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struct rtdPrivate {
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	/* memory mapped board structures */
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	void __iomem *las0;
	void __iomem *las1;
	void __iomem *lcfg;
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	long aiCount;		/* total transfer size (samples) */
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	int transCount;		/* # to transfer data. 0->1/2FIFO */
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	int flags;		/* flag event modes */

	/* channel list info */
	/* chanBipolar tracks whether a channel is bipolar (and needs +2048) */
	unsigned char chanBipolar[RTD_MAX_CHANLIST / 8];	/* bit array */

	/* read back data */
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	unsigned int aoValue[2];	/* Used for AO read back */
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	/* timer gate (when enabled) */
	u8 utcGate[4];		/* 1 extra allows simple range check */

	unsigned fifoLen;
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};
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/* bit defines for "flags" */
#define SEND_EOS	0x01	/* send End Of Scan events */
#define DMA0_ACTIVE	0x02	/* DMA0 is active */
#define DMA1_ACTIVE	0x04	/* DMA1 is active */

/* Macros for accessing channel list bit array */
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#define CHAN_ARRAY_TEST(array, index) \
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	(((array)[(index)/8] >> ((index) & 0x7)) & 0x1)
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#define CHAN_ARRAY_SET(array, index) \
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	(((array)[(index)/8] |= 1 << ((index) & 0x7)))
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#define CHAN_ARRAY_CLEAR(array, index) \
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	(((array)[(index)/8] &= ~(1 << ((index) & 0x7))))

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/*
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  Given a desired period and the clock period (both in ns),
  return the proper counter value (divider-1).
  Sets the original period to be the true value.
  Note: you have to check if the value is larger than the counter range!
*/
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static int rtd_ns_to_timer_base(unsigned int *nanosec,
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				int round_mode, int base)
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{
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
	int divider;

	switch (round_mode) {
	case TRIG_ROUND_NEAREST:
	default:
		divider = (*nanosec + base / 2) / base;
		break;
	case TRIG_ROUND_DOWN:
		divider = (*nanosec) / base;
		break;
	case TRIG_ROUND_UP:
		divider = (*nanosec + base - 1) / base;
		break;
	}
	if (divider < 2)
		divider = 2;	/* min is divide by 2 */

	/* Note: we don't check for max, because different timers
	   have different ranges */

	*nanosec = base * divider;
	return divider - 1;	/* countdown is divisor+1 */
}
463
464

/*
465
466
467
468
469
470
471
472
  Given a desired period (in ns),
  return the proper counter value (divider-1) for the internal clock.
  Sets the original period to be the true value.
*/
static int rtd_ns_to_timer(unsigned int *ns, int round_mode)
{
	return rtd_ns_to_timer_base(ns, round_mode, RTD_CLOCK_BASE);
}
473

474
475
476
477
478
479
/*
  Convert a single comedi channel-gain entry to a RTD520 table entry
*/
static unsigned short rtdConvertChanGain(struct comedi_device *dev,
					 unsigned int comediChan, int chanIndex)
{				/* index in channel list */
480
	const struct rtdBoard *thisboard = comedi_board(dev);
481
	struct rtdPrivate *devpriv = dev->private;
482
483
	unsigned int chan, range, aref;
	unsigned short r = 0;
484

485
486
487
	chan = CR_CHAN(comediChan);
	range = CR_RANGE(comediChan);
	aref = CR_AREF(comediChan);
488

489
	r |= chan & 0xf;
490

491
	/* Note: we also setup the channel list bipolar flag array */
492
493
494
495
	if (range < thisboard->range10Start) {
		/* +-5 range */
		r |= 0x000;
		r |= (range & 0x7) << 4;
496
		CHAN_ARRAY_SET(devpriv->chanBipolar, chanIndex);
497
498
499
	} else if (range < thisboard->rangeUniStart) {
		/* +-10 range */
		r |= 0x100;
500
501
		r |= ((range - thisboard->range10Start) & 0x7) << 4;
		CHAN_ARRAY_SET(devpriv->chanBipolar, chanIndex);
502
503
504
	} else {
		/* +10 range */
		r |= 0x200;
505
506
507
		r |= ((range - thisboard->rangeUniStart) & 0x7) << 4;
		CHAN_ARRAY_CLEAR(devpriv->chanBipolar, chanIndex);
	}
508

509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
	switch (aref) {
	case AREF_GROUND:	/* on-board ground */
		break;

	case AREF_COMMON:
		r |= 0x80;	/* ref external analog common */
		break;

	case AREF_DIFF:
		r |= 0x400;	/* differential inputs */
		break;

	case AREF_OTHER:	/* ??? */
		break;
	}
	/*printk ("chan=%d r=%d a=%d -> 0x%x\n",
	   chan, range, aref, r); */
	return r;
}

/*
  Setup the channel-gain table from a comedi list
*/
static void rtd_load_channelgain_list(struct comedi_device *dev,
				      unsigned int n_chan, unsigned int *list)
{
535
536
	struct rtdPrivate *devpriv = dev->private;

537
538
	if (n_chan > 1) {	/* setup channel gain table */
		int ii;
539
540

		writel(0, devpriv->las0 + LAS0_CGT_CLEAR);
541
		writel(1, devpriv->las0 + LAS0_CGT_ENABLE);
542
		for (ii = 0; ii < n_chan; ii++) {
543
544
			writel(rtdConvertChanGain(dev, list[ii], ii),
				devpriv->las0 + LAS0_CGT_WRITE);
545
		}
546
	} else {		/* just use the channel gain latch */
547
		writel(0, devpriv->las0 + LAS0_CGT_ENABLE);
548
549
		writel(rtdConvertChanGain(dev, list[0], 0),
			devpriv->las0 + LAS0_CGL_WRITE);
550
	}
551
552
553
554
555
556
}

/* determine fifo size by doing adc conversions until the fifo half
empty status flag clears */
static int rtd520_probe_fifo_depth(struct comedi_device *dev)
{
557
	struct rtdPrivate *devpriv = dev->private;
558
559
560
561
562
	unsigned int chanspec = CR_PACK(0, 0, AREF_GROUND);
	unsigned i;
	static const unsigned limit = 0x2000;
	unsigned fifo_size = 0;

563
	writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
564
	rtd_load_channelgain_list(dev, 1, &chanspec);
565
	/* ADC conversion trigger source: SOFTWARE */
566
	writel(0, devpriv->las0 + LAS0_ADC_CONVERSION);
567
568
569
570
	/* convert  samples */
	for (i = 0; i < limit; ++i) {
		unsigned fifo_status;
		/* trigger conversion */
571
		writew(0, devpriv->las0 + LAS0_ADC);
572
		udelay(1);
573
		fifo_status = readl(devpriv->las0 + LAS0_ADC);
574
575
576
		if ((fifo_status & FS_ADC_HEMPTY) == 0) {
			fifo_size = 2 * i;
			break;
577
		}
578
579
	}
	if (i == limit) {
580
		dev_info(dev->class_dev, "failed to probe fifo size.\n");
581
582
		return -EIO;
	}
583
	writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
584
	if (fifo_size != 0x400 && fifo_size != 0x2000) {
585
586
587
		dev_info(dev->class_dev,
			 "unexpected fifo size of %i, expected 1024 or 8192.\n",
			 fifo_size);
588
		return -EIO;
589
	}
590
591
	return fifo_size;
}
592

593
594
595
596
/*
  "instructions" read/write data in "one-shot" or "software-triggered"
  mode (simplest case).
  This doesn't use interrupts.
597

598
599
600
601
602
603
604
  Note, we don't do any settling delays.  Use a instruction list to
  select, delay, then read.
 */
static int rtd_ai_rinsn(struct comedi_device *dev,
			struct comedi_subdevice *s, struct comedi_insn *insn,
			unsigned int *data)
{
605
	struct rtdPrivate *devpriv = dev->private;
606
607
	int n, ii;
	int stat;
608

609
	/* clear any old fifo data */
610
	writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
611

612
613
	/* write channel to multiplexer and clear channel gain table */
	rtd_load_channelgain_list(dev, 1, &insn->chanspec);
614

615
	/* ADC conversion trigger source: SOFTWARE */
616
	writel(0, devpriv->las0 + LAS0_ADC_CONVERSION);
617

618
619
620
621
	/* convert n samples */
	for (n = 0; n < insn->n; n++) {
		s16 d;
		/* trigger conversion */
622
		writew(0, devpriv->las0 + LAS0_ADC);
623
624

		for (ii = 0; ii < RTD_ADC_TIMEOUT; ++ii) {
625
			stat = readl(devpriv->las0 + LAS0_ADC);
626
627
628
629
			if (stat & FS_ADC_NOT_EMPTY)	/* 1 -> not empty */
				break;
			WAIT_QUIETLY;
		}
630
		if (ii >= RTD_ADC_TIMEOUT)
631
632
633
			return -ETIMEDOUT;

		/* read data */
634
		d = readw(devpriv->las1 + LAS1_ADC_FIFO);
635
636
637
638
639
640
641
		/*printk ("rtd520: Got 0x%x after %d usec\n", d, ii+1); */
		d = d >> 3;	/* low 3 bits are marker lines */
		if (CHAN_ARRAY_TEST(devpriv->chanBipolar, 0))
			/* convert to comedi unsigned data */
			data[n] = d + 2048;
		else
			data[n] = d;
642
643
	}

644
645
646
	/* return the number of samples read/written */
	return n;
}
647

648
649
650
/*
  Get what we know is there.... Fast!
  This uses 1/2 the bus cycles of read_dregs (below).
651

652
653
654
655
656
  The manual claims that we can do a lword read, but it doesn't work here.
*/
static int ai_read_n(struct comedi_device *dev, struct comedi_subdevice *s,
		     int count)
{
657
	struct rtdPrivate *devpriv = dev->private;
658
	int ii;
659

660
661
662
	for (ii = 0; ii < count; ii++) {
		short sample;
		s16 d;
663

664
		if (0 == devpriv->aiCount) {	/* done */
665
			d = readw(devpriv->las1 + LAS1_ADC_FIFO);
666
667
			continue;
		}
668

669
		d = readw(devpriv->las1 + LAS1_ADC_FIFO);
670
671
672
673
674
675
		d = d >> 3;	/* low 3 bits are marker lines */
		if (CHAN_ARRAY_TEST(devpriv->chanBipolar, s->async->cur_chan)) {
			/* convert to comedi unsigned data */
			sample = d + 2048;
		} else
			sample = d;
676

677
678
		if (!comedi_buf_put(s->async, sample))
			return -1;
679

680
681
682
683
684
		if (devpriv->aiCount > 0)	/* < 0, means read forever */
			devpriv->aiCount--;
	}
	return 0;
}
685

686
687
688
689
690
/*
  unknown amout of data is waiting in fifo.
*/
static int ai_read_dregs(struct comedi_device *dev, struct comedi_subdevice *s)
{
691
692
	struct rtdPrivate *devpriv = dev->private;

693
	while (readl(devpriv->las0 + LAS0_ADC) & FS_ADC_NOT_EMPTY) {
694
		short sample;
695
		s16 d = readw(devpriv->las1 + LAS1_ADC_FIFO);
696

697
698
699
		if (0 == devpriv->aiCount) {	/* done */
			continue;	/* read rest */
		}
700

701
702
703
704
705
706
		d = d >> 3;	/* low 3 bits are marker lines */
		if (CHAN_ARRAY_TEST(devpriv->chanBipolar, s->async->cur_chan)) {
			/* convert to comedi unsigned data */
			sample = d + 2048;
		} else
			sample = d;
707

708
709
		if (!comedi_buf_put(s->async, sample))
			return -1;
710

711
712
713
714
715
		if (devpriv->aiCount > 0)	/* < 0, means read forever */
			devpriv->aiCount--;
	}
	return 0;
}
716

717
718
719
720
721
722
723
724
725
/*
  Handle all rtd520 interrupts.
  Runs atomically and is never re-entered.
  This is a "slow handler";  other interrupts may be active.
  The data conversion may someday happen in a "bottom half".
*/
static irqreturn_t rtd_interrupt(int irq,	/* interrupt number (ignored) */
				 void *d)
{				/* our data *//* cpu context (ignored) */
726
	struct comedi_device *dev = d;
727
	struct comedi_subdevice *s = &dev->subdevices[0];
728
	struct rtdPrivate *devpriv = dev->private;
729
	u32 overrun;
730
731
	u16 status;
	u16 fifoStatus;
732

733
734
	if (!dev->attached)
		return IRQ_NONE;
735

736
	fifoStatus = readl(devpriv->las0 + LAS0_ADC);
737
	/* check for FIFO full, this automatically halts the ADC! */
738
	if (!(fifoStatus & FS_ADC_NOT_FULL))	/* 0 -> full */
739
740
		goto abortTransfer;

741
	status = readw(devpriv->las0 + LAS0_IT);
742
743
744
745
746
	/* if interrupt was not caused by our board, or handled above */
	if (0 == status)
		return IRQ_HANDLED;

	if (status & IRQM_ADC_ABOUT_CNT) {	/* sample count -> read FIFO */
747
748
749
750
751
752
753
754
		/*
		 * since the priority interrupt controller may have queued
		 * a sample counter interrupt, even though we have already
		 * finished, we must handle the possibility that there is
		 * no data here
		 */
		if (!(fifoStatus & FS_ADC_HEMPTY)) {
			/* FIFO half full */
755
			if (ai_read_n(dev, s, devpriv->fifoLen / 2) < 0)
756
				goto abortTransfer;
757
758

			if (0 == devpriv->aiCount)
759
				goto transferDone;
760

761
			comedi_event(dev, s);
762
763
764
		} else if (devpriv->transCount > 0) {
			if (fifoStatus & FS_ADC_NOT_EMPTY) {
				/* FIFO not empty */
765
				if (ai_read_n(dev, s, devpriv->transCount) < 0)
766
					goto abortTransfer;
767
768

				if (0 == devpriv->aiCount)
769
					goto transferDone;
770

771
772
				comedi_event(dev, s);
			}
773
774
775
		}
	}

776
	overrun = readl(devpriv->las0 + LAS0_OVERRUN) & 0xffff;
777
	if (overrun)
778
		goto abortTransfer;
779

780
	/* clear the interrupt */
781
	writew(status, devpriv->las0 + LAS0_CLEAR);
782
	readw(devpriv->las0 + LAS0_CLEAR);
783
	return IRQ_HANDLED;
784

785
abortTransfer:
786
	writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
787
788
789
	s->async->events |= COMEDI_CB_ERROR;
	devpriv->aiCount = 0;	/* stop and don't transfer any more */
	/* fall into transferDone */
790

791
transferDone:
792
	/* pacer stop source: SOFTWARE */
793
	writel(0, devpriv->las0 + LAS0_PACER_STOP);
794
	writel(0, devpriv->las0 + LAS0_PACER);	/* stop pacer */
795
	writel(0, devpriv->las0 + LAS0_ADC_CONVERSION);
796
	writew(0, devpriv->las0 + LAS0_IT);
797

798
	if (devpriv->aiCount > 0) {	/* there shouldn't be anything left */
799
		fifoStatus = readl(devpriv->las0 + LAS0_ADC);
800
801
		ai_read_dregs(dev, s);	/* read anything left in FIFO */
	}
802

803
804
	s->async->events |= COMEDI_CB_EOA;	/* signal end to comedi */
	comedi_event(dev, s);
805

806
	/* clear the interrupt */
807
	status = readw(devpriv->las0 + LAS0_IT);
808
	writew(status, devpriv->las0 + LAS0_CLEAR);
809
	readw(devpriv->las0 + LAS0_CLEAR);
810

811
	fifoStatus = readl(devpriv->las0 + LAS0_ADC);
812
	overrun = readl(devpriv->las0 + LAS0_OVERRUN) & 0xffff;
813
814

	return IRQ_HANDLED;
815
816
}

817
818
819
/*
  cmdtest tests a particular command to see if it is valid.
  Using the cmdtest ioctl, a user can create a valid cmd
820
  and then have it executed by the cmd ioctl (asynchronously).
821
822
823
824
825
826
827

  cmdtest returns 1,2,3,4 or 0, depending on which tests
  the command passes.
*/

static int rtd_ai_cmdtest(struct comedi_device *dev,
			  struct comedi_subdevice *s, struct comedi_cmd *cmd)
828
{
829
830
	int err = 0;
	int tmp;
831

832
	/* Step 1 : check if triggers are trivially valid */
833

834
835
836
837
838
839
	err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW);
	err |= cfc_check_trigger_src(&cmd->scan_begin_src,
					TRIG_TIMER | TRIG_EXT);
	err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_TIMER | TRIG_EXT);
	err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
	err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
840
841
842
843

	if (err)
		return 1;

844
	/* Step 2a : make sure trigger sources are unique */
845

846
847
848
849
850
	err |= cfc_check_trigger_is_unique(cmd->scan_begin_src);
	err |= cfc_check_trigger_is_unique(cmd->convert_src);
	err |= cfc_check_trigger_is_unique(cmd->stop_src);

	/* Step 2b : and mutually compatible */
851

852
853
	if (err)
		return 2;
854

855
	/* Step 3: check if arguments are trivially valid */
856

857
	err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
858

859
860
861
	if (cmd->scan_begin_src == TRIG_TIMER) {
		/* Note: these are time periods, not actual rates */
		if (1 == cmd->chanlist_len) {	/* no scanning */
862
863
			if (cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
						      RTD_MAX_SPEED_1)) {
864
865
				rtd_ns_to_timer(&cmd->scan_begin_arg,
						TRIG_ROUND_UP);
866
				err |= -EINVAL;
867
			}
868
869
			if (cfc_check_trigger_arg_max(&cmd->scan_begin_arg,
						      RTD_MIN_SPEED_1)) {
870
871
				rtd_ns_to_timer(&cmd->scan_begin_arg,
						TRIG_ROUND_DOWN);
872
				err |= -EINVAL;
873
874
			}
		} else {
875
876
			if (cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
						      RTD_MAX_SPEED)) {
877
878
				rtd_ns_to_timer(&cmd->scan_begin_arg,
						TRIG_ROUND_UP);
879
				err |= -EINVAL;
880
			}
881
882
			if (cfc_check_trigger_arg_max(&cmd->scan_begin_arg,
						      RTD_MIN_SPEED)) {
883
884
				rtd_ns_to_timer(&cmd->scan_begin_arg,
						TRIG_ROUND_DOWN);
885
				err |= -EINVAL;
886
			}
887
		}
888
889
890
891
	} else {
		/* external trigger */
		/* should be level/edge, hi/lo specification here */
		/* should specify multiple external triggers */
892
		err |= cfc_check_trigger_arg_max(&cmd->scan_begin_arg, 9);
893
	}
894

895
896
	if (cmd->convert_src == TRIG_TIMER) {
		if (1 == cmd->chanlist_len) {	/* no scanning */
897
898
			if (cfc_check_trigger_arg_min(&cmd->convert_arg,
						      RTD_MAX_SPEED_1)) {
899
900
				rtd_ns_to_timer(&cmd->convert_arg,
						TRIG_ROUND_UP);
901
				err |= -EINVAL;
902
			}
903
904
			if (cfc_check_trigger_arg_max(&cmd->convert_arg,
						      RTD_MIN_SPEED_1)) {
905
906
				rtd_ns_to_timer(&cmd->convert_arg,
						TRIG_ROUND_DOWN);
907
				err |= -EINVAL;
908
909
			}
		} else {
910
911
			if (cfc_check_trigger_arg_min(&cmd->convert_arg,
						      RTD_MAX_SPEED)) {
912
913
				rtd_ns_to_timer(&cmd->convert_arg,
						TRIG_ROUND_UP);
914
				err |= -EINVAL;
915
			}
916
917
			if (cfc_check_trigger_arg_max(&cmd->convert_arg,
						      RTD_MIN_SPEED)) {
918
919
				rtd_ns_to_timer(&cmd->convert_arg,
						TRIG_ROUND_DOWN);
920
				err |= -EINVAL;
921
922
923
924
925
			}
		}
	} else {
		/* external trigger */
		/* see above */
926
		err |= cfc_check_trigger_arg_max(&cmd->convert_arg, 9);
927
928
929
930
931
932
	}

	if (cmd->stop_src == TRIG_COUNT) {
		/* TODO check for rounding error due to counter wrap */
	} else {
		/* TRIG_NONE */
933
		err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
934
	}
935

936
937
	if (err)
		return 3;
938

939
940
941
942
943
944

	/* step 4: fix up any arguments */

	if (cmd->chanlist_len > RTD_MAX_CHANLIST) {
		cmd->chanlist_len = RTD_MAX_CHANLIST;
		err++;
945
	}
946
947
948
949
950
951
	if (cmd->scan_begin_src == TRIG_TIMER) {
		tmp = cmd->scan_begin_arg;
		rtd_ns_to_timer(&cmd->scan_begin_arg,
				cmd->flags & TRIG_ROUND_MASK);
		if (tmp != cmd->scan_begin_arg)
			err++;
952

953
954
955
956
957
958
959
	}
	if (cmd->convert_src == TRIG_TIMER) {
		tmp = cmd->convert_arg;
		rtd_ns_to_timer(&cmd->convert_arg,
				cmd->flags & TRIG_ROUND_MASK);
		if (tmp != cmd->convert_arg)
			err++;
960

961
962
963
964
965
966
		if (cmd->scan_begin_src == TRIG_TIMER
		    && (cmd->scan_begin_arg
			< (cmd->convert_arg * cmd->scan_end_arg))) {
			cmd->scan_begin_arg =
			    cmd->convert_arg * cmd->scan_end_arg;
			err++;
967
		}
968
	}
969

970
971
	if (err)
		return 4;
972
973
974
975
976

	return 0;
}

/*
977
978
979
980
  Execute a analog in command with many possible triggering options.
  The data get stored in the async structure of the subdevice.
  This is usually done by an interrupt handler.
  Userland gets to the data using read calls.
981
*/
982
983
static int rtd_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{
984
	struct rtdPrivate *devpriv = dev->private;
985
986
	struct comedi_cmd *cmd = &s->async->cmd;
	int timer;
987

988
	/* stop anything currently running */
989
	/* pacer stop source: SOFTWARE */
990
	writel(0, devpriv->las0 + LAS0_PACER_STOP);
991
	writel(0, devpriv->las0 + LAS0_PACER);	/* stop pacer */
992
	writel(0, devpriv->las0 + LAS0_ADC_CONVERSION);
993
	writew(0, devpriv->las0 + LAS0_IT);
994
	writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
995
	writel(0, devpriv->las0 + LAS0_OVERRUN);
996

997
998
999
	/* start configuration */
	/* load channel list and reset CGT */
	rtd_load_channelgain_list(dev, cmd->chanlist_len, cmd->chanlist);
1000