brintos

brintos / linux-shallow public Read only

0
0
Text · 66.2 KiB · 0919ed9 Raw
2227 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/* Low-level parallel port routines for built-in port on SGI IP323 *4 * Author: Arnaud Giersch <arnaud.giersch@free.fr>5 *6 * Based on parport_pc.c by7 *	Phil Blundell, Tim Waugh, Jose Renau, David Campbell,8 *	Andrea Arcangeli, et al.9 *10 * Thanks to Ilya A. Volynets-Evenbakh for his help.11 *12 * Copyright (C) 2005, 2006 Arnaud Giersch.13 */14 15/* Current status:16 *17 *	Basic SPP and PS2 modes are supported.18 *	Support for parallel port IRQ is present.19 *	Hardware SPP (a.k.a. compatibility), EPP, and ECP modes are20 *	supported.21 *	SPP/ECP FIFO can be driven in PIO or DMA mode.  PIO mode can work with22 *	or without interrupt support.23 *24 *	Hardware ECP mode is not fully implemented (ecp_read_data and25 *	ecp_write_addr are actually missing).26 *27 * To do:28 *29 *	Fully implement ECP mode.30 *	EPP and ECP mode need to be tested.  I currently do not own any31 *	peripheral supporting these extended mode, and cannot test them.32 *	If DMA mode works well, decide if support for PIO FIFO modes should be33 *	dropped.34 *	Use the io{read,write} family functions when they become available in35 *	the linux-mips.org tree.  Note: the MIPS specific functions readsb()36 *	and writesb() are to be translated by ioread8_rep() and iowrite8_rep()37 *	respectively.38 */39 40/* The built-in parallel port on the SGI 02 workstation (a.k.a. IP32) is an41 * IEEE 1284 parallel port driven by a Texas Instrument TL16PIR552PH chip[1].42 * This chip supports SPP, bidirectional, EPP and ECP modes.  It has a 16 byte43 * FIFO buffer and supports DMA transfers.44 *45 * [1] http://focus.ti.com/docs/prod/folders/print/tl16pir552.html46 *47 * Theoretically, we could simply use the parport_pc module.  It is however48 * not so simple.  The parport_pc code assumes that the parallel port49 * registers are port-mapped.  On the O2, they are memory-mapped.50 * Furthermore, each register is replicated on 256 consecutive addresses (as51 * it is for the built-in serial ports on the same chip).52 */53 54/*--- Some configuration defines ---------------------------------------*/55 56/* DEBUG_PARPORT_IP3257 *	0	disable debug58 *	1	standard level: pr_debug1 is enabled59 *	2	parport_ip32_dump_state is enabled60 *	>=3	verbose level: pr_debug is enabled61 */62#if !defined(DEBUG_PARPORT_IP32)63#	define DEBUG_PARPORT_IP32  0	/* 0 (disabled) for production */64#endif65 66/*----------------------------------------------------------------------*/67 68/* Setup DEBUG macros.  This is done before any includes, just in case we69 * activate pr_debug() with DEBUG_PARPORT_IP32 >= 3.70 */71#if DEBUG_PARPORT_IP32 == 172#	warning DEBUG_PARPORT_IP32 == 173#elif DEBUG_PARPORT_IP32 == 274#	warning DEBUG_PARPORT_IP32 == 275#elif DEBUG_PARPORT_IP32 >= 376#	warning DEBUG_PARPORT_IP32 >= 377#	if !defined(DEBUG)78#		define DEBUG /* enable pr_debug() in kernel.h */79#	endif80#endif81 82#include <linux/completion.h>83#include <linux/delay.h>84#include <linux/dma-mapping.h>85#include <linux/err.h>86#include <linux/init.h>87#include <linux/interrupt.h>88#include <linux/jiffies.h>89#include <linux/kernel.h>90#include <linux/module.h>91#include <linux/parport.h>92#include <linux/sched/signal.h>93#include <linux/slab.h>94#include <linux/spinlock.h>95#include <linux/stddef.h>96#include <linux/types.h>97#include <asm/io.h>98#include <asm/ip32/ip32_ints.h>99#include <asm/ip32/mace.h>100 101/*--- Global variables -------------------------------------------------*/102 103/* Verbose probing on by default for debugging. */104#if DEBUG_PARPORT_IP32 >= 1105#	define DEFAULT_VERBOSE_PROBING	1106#else107#	define DEFAULT_VERBOSE_PROBING	0108#endif109 110/* Default prefix for printk */111#define PPIP32 "parport_ip32: "112 113/*114 * These are the module parameters:115 * @features:		bit mask of features to enable/disable116 *			(all enabled by default)117 * @verbose_probing:	log chit-chat during initialization118 */119#define PARPORT_IP32_ENABLE_IRQ	(1U << 0)120#define PARPORT_IP32_ENABLE_DMA	(1U << 1)121#define PARPORT_IP32_ENABLE_SPP	(1U << 2)122#define PARPORT_IP32_ENABLE_EPP	(1U << 3)123#define PARPORT_IP32_ENABLE_ECP	(1U << 4)124static unsigned int features =	~0U;125static bool verbose_probing =	DEFAULT_VERBOSE_PROBING;126 127/* We do not support more than one port. */128static struct parport *this_port;129 130/* Timing constants for FIFO modes.  */131#define FIFO_NFAULT_TIMEOUT	100	/* milliseconds */132#define FIFO_POLLING_INTERVAL	50	/* microseconds */133 134/*--- I/O register definitions -----------------------------------------*/135 136/**137 * struct parport_ip32_regs - virtual addresses of parallel port registers138 * @data:	Data Register139 * @dsr:	Device Status Register140 * @dcr:	Device Control Register141 * @eppAddr:	EPP Address Register142 * @eppData0:	EPP Data Register 0143 * @eppData1:	EPP Data Register 1144 * @eppData2:	EPP Data Register 2145 * @eppData3:	EPP Data Register 3146 * @ecpAFifo:	ECP Address FIFO147 * @fifo:	General FIFO register.  The same address is used for:148 *		- cFifo, the Parallel Port DATA FIFO149 *		- ecpDFifo, the ECP Data FIFO150 *		- tFifo, the ECP Test FIFO151 * @cnfgA:	Configuration Register A152 * @cnfgB:	Configuration Register B153 * @ecr:	Extended Control Register154 */155struct parport_ip32_regs {156	void __iomem *data;157	void __iomem *dsr;158	void __iomem *dcr;159	void __iomem *eppAddr;160	void __iomem *eppData0;161	void __iomem *eppData1;162	void __iomem *eppData2;163	void __iomem *eppData3;164	void __iomem *ecpAFifo;165	void __iomem *fifo;166	void __iomem *cnfgA;167	void __iomem *cnfgB;168	void __iomem *ecr;169};170 171/* Device Status Register */172#define DSR_nBUSY		(1U << 7)	/* PARPORT_STATUS_BUSY */173#define DSR_nACK		(1U << 6)	/* PARPORT_STATUS_ACK */174#define DSR_PERROR		(1U << 5)	/* PARPORT_STATUS_PAPEROUT */175#define DSR_SELECT		(1U << 4)	/* PARPORT_STATUS_SELECT */176#define DSR_nFAULT		(1U << 3)	/* PARPORT_STATUS_ERROR */177#define DSR_nPRINT		(1U << 2)	/* specific to TL16PIR552 */178/* #define DSR_reserved		(1U << 1) */179#define DSR_TIMEOUT		(1U << 0)	/* EPP timeout */180 181/* Device Control Register */182/* #define DCR_reserved		(1U << 7) | (1U <<  6) */183#define DCR_DIR			(1U << 5)	/* direction */184#define DCR_IRQ			(1U << 4)	/* interrupt on nAck */185#define DCR_SELECT		(1U << 3)	/* PARPORT_CONTROL_SELECT */186#define DCR_nINIT		(1U << 2)	/* PARPORT_CONTROL_INIT */187#define DCR_AUTOFD		(1U << 1)	/* PARPORT_CONTROL_AUTOFD */188#define DCR_STROBE		(1U << 0)	/* PARPORT_CONTROL_STROBE */189 190/* ECP Configuration Register A */191#define CNFGA_IRQ		(1U << 7)192#define CNFGA_ID_MASK		((1U << 6) | (1U << 5) | (1U << 4))193#define CNFGA_ID_SHIFT		4194#define CNFGA_ID_16		(00U << CNFGA_ID_SHIFT)195#define CNFGA_ID_8		(01U << CNFGA_ID_SHIFT)196#define CNFGA_ID_32		(02U << CNFGA_ID_SHIFT)197/* #define CNFGA_reserved	(1U << 3) */198#define CNFGA_nBYTEINTRANS	(1U << 2)199#define CNFGA_PWORDLEFT		((1U << 1) | (1U << 0))200 201/* ECP Configuration Register B */202#define CNFGB_COMPRESS		(1U << 7)203#define CNFGB_INTRVAL		(1U << 6)204#define CNFGB_IRQ_MASK		((1U << 5) | (1U << 4) | (1U << 3))205#define CNFGB_IRQ_SHIFT		3206#define CNFGB_DMA_MASK		((1U << 2) | (1U << 1) | (1U << 0))207#define CNFGB_DMA_SHIFT		0208 209/* Extended Control Register */210#define ECR_MODE_MASK		((1U << 7) | (1U << 6) | (1U << 5))211#define ECR_MODE_SHIFT		5212#define ECR_MODE_SPP		(00U << ECR_MODE_SHIFT)213#define ECR_MODE_PS2		(01U << ECR_MODE_SHIFT)214#define ECR_MODE_PPF		(02U << ECR_MODE_SHIFT)215#define ECR_MODE_ECP		(03U << ECR_MODE_SHIFT)216#define ECR_MODE_EPP		(04U << ECR_MODE_SHIFT)217/* #define ECR_MODE_reserved	(05U << ECR_MODE_SHIFT) */218#define ECR_MODE_TST		(06U << ECR_MODE_SHIFT)219#define ECR_MODE_CFG		(07U << ECR_MODE_SHIFT)220#define ECR_nERRINTR		(1U << 4)221#define ECR_DMAEN		(1U << 3)222#define ECR_SERVINTR		(1U << 2)223#define ECR_F_FULL		(1U << 1)224#define ECR_F_EMPTY		(1U << 0)225 226/*--- Private data -----------------------------------------------------*/227 228/**229 * enum parport_ip32_irq_mode - operation mode of interrupt handler230 * @PARPORT_IP32_IRQ_FWD:	forward interrupt to the upper parport layer231 * @PARPORT_IP32_IRQ_HERE:	interrupt is handled locally232 */233enum parport_ip32_irq_mode { PARPORT_IP32_IRQ_FWD, PARPORT_IP32_IRQ_HERE };234 235/**236 * struct parport_ip32_private - private stuff for &struct parport237 * @regs:		register addresses238 * @dcr_cache:		cached contents of DCR239 * @dcr_writable:	bit mask of writable DCR bits240 * @pword:		number of bytes per PWord241 * @fifo_depth:		number of PWords that FIFO will hold242 * @readIntrThreshold:	minimum number of PWords we can read243 *			if we get an interrupt244 * @writeIntrThreshold:	minimum number of PWords we can write245 *			if we get an interrupt246 * @irq_mode:		operation mode of interrupt handler for this port247 * @irq_complete:	mutex used to wait for an interrupt to occur248 */249struct parport_ip32_private {250	struct parport_ip32_regs	regs;251	unsigned int			dcr_cache;252	unsigned int			dcr_writable;253	unsigned int			pword;254	unsigned int			fifo_depth;255	unsigned int			readIntrThreshold;256	unsigned int			writeIntrThreshold;257	enum parport_ip32_irq_mode	irq_mode;258	struct completion		irq_complete;259};260 261/*--- Debug code -------------------------------------------------------*/262 263/*264 * pr_debug1 - print debug messages265 *266 * This is like pr_debug(), but is defined for %DEBUG_PARPORT_IP32 >= 1267 */268#if DEBUG_PARPORT_IP32 >= 1269#	define pr_debug1(...)	printk(KERN_DEBUG __VA_ARGS__)270#else /* DEBUG_PARPORT_IP32 < 1 */271#	define pr_debug1(...)	do { } while (0)272#endif273 274/*275 * pr_trace, pr_trace1 - trace function calls276 * @p:		pointer to &struct parport277 * @fmt:	printk format string278 * @...:	parameters for format string279 *280 * Macros used to trace function calls.  The given string is formatted after281 * function name.  pr_trace() uses pr_debug(), and pr_trace1() uses282 * pr_debug1().  __pr_trace() is the low-level macro and is not to be used283 * directly.284 */285#define __pr_trace(pr, p, fmt, ...)					\286	pr("%s: %s" fmt "\n",						\287	   ({ const struct parport *__p = (p);				\288		   __p ? __p->name : "parport_ip32"; }),		\289	   __func__ , ##__VA_ARGS__)290#define pr_trace(p, fmt, ...)	__pr_trace(pr_debug, p, fmt , ##__VA_ARGS__)291#define pr_trace1(p, fmt, ...)	__pr_trace(pr_debug1, p, fmt , ##__VA_ARGS__)292 293/*294 * __pr_probe, pr_probe - print message if @verbose_probing is true295 * @p:		pointer to &struct parport296 * @fmt:	printk format string297 * @...:	parameters for format string298 *299 * For new lines, use pr_probe().  Use __pr_probe() for continued lines.300 */301#define __pr_probe(...)							\302	do { if (verbose_probing) printk(__VA_ARGS__); } while (0)303#define pr_probe(p, fmt, ...)						\304	__pr_probe(KERN_INFO PPIP32 "0x%lx: " fmt, (p)->base , ##__VA_ARGS__)305 306/*307 * parport_ip32_dump_state - print register status of parport308 * @p:		pointer to &struct parport309 * @str:	string to add in message310 * @show_ecp_config:	shall we dump ECP configuration registers too?311 *312 * This function is only here for debugging purpose, and should be used with313 * care.  Reading the parallel port registers may have undesired side effects.314 * Especially if @show_ecp_config is true, the parallel port is resetted.315 * This function is only defined if %DEBUG_PARPORT_IP32 >= 2.316 */317#if DEBUG_PARPORT_IP32 >= 2318static void parport_ip32_dump_state(struct parport *p, char *str,319				    unsigned int show_ecp_config)320{321	struct parport_ip32_private * const priv = p->physport->private_data;322	unsigned int i;323 324	printk(KERN_DEBUG PPIP32 "%s: state (%s):\n", p->name, str);325	{326		static const char ecr_modes[8][4] = {"SPP", "PS2", "PPF",327						     "ECP", "EPP", "???",328						     "TST", "CFG"};329		unsigned int ecr = readb(priv->regs.ecr);330		printk(KERN_DEBUG PPIP32 "    ecr=0x%02x", ecr);331		pr_cont(" %s",332			ecr_modes[(ecr & ECR_MODE_MASK) >> ECR_MODE_SHIFT]);333		if (ecr & ECR_nERRINTR)334			pr_cont(",nErrIntrEn");335		if (ecr & ECR_DMAEN)336			pr_cont(",dmaEn");337		if (ecr & ECR_SERVINTR)338			pr_cont(",serviceIntr");339		if (ecr & ECR_F_FULL)340			pr_cont(",f_full");341		if (ecr & ECR_F_EMPTY)342			pr_cont(",f_empty");343		pr_cont("\n");344	}345	if (show_ecp_config) {346		unsigned int oecr, cnfgA, cnfgB;347		oecr = readb(priv->regs.ecr);348		writeb(ECR_MODE_PS2, priv->regs.ecr);349		writeb(ECR_MODE_CFG, priv->regs.ecr);350		cnfgA = readb(priv->regs.cnfgA);351		cnfgB = readb(priv->regs.cnfgB);352		writeb(ECR_MODE_PS2, priv->regs.ecr);353		writeb(oecr, priv->regs.ecr);354		printk(KERN_DEBUG PPIP32 "    cnfgA=0x%02x", cnfgA);355		pr_cont(" ISA-%s", (cnfgA & CNFGA_IRQ) ? "Level" : "Pulses");356		switch (cnfgA & CNFGA_ID_MASK) {357		case CNFGA_ID_8:358			pr_cont(",8 bits");359			break;360		case CNFGA_ID_16:361			pr_cont(",16 bits");362			break;363		case CNFGA_ID_32:364			pr_cont(",32 bits");365			break;366		default:367			pr_cont(",unknown ID");368			break;369		}370		if (!(cnfgA & CNFGA_nBYTEINTRANS))371			pr_cont(",ByteInTrans");372		if ((cnfgA & CNFGA_ID_MASK) != CNFGA_ID_8)373			pr_cont(",%d byte%s left",374				cnfgA & CNFGA_PWORDLEFT,375				((cnfgA & CNFGA_PWORDLEFT) > 1) ? "s" : "");376		pr_cont("\n");377		printk(KERN_DEBUG PPIP32 "    cnfgB=0x%02x", cnfgB);378		pr_cont(" irq=%u,dma=%u",379			(cnfgB & CNFGB_IRQ_MASK) >> CNFGB_IRQ_SHIFT,380			(cnfgB & CNFGB_DMA_MASK) >> CNFGB_DMA_SHIFT);381		pr_cont(",intrValue=%d", !!(cnfgB & CNFGB_INTRVAL));382		if (cnfgB & CNFGB_COMPRESS)383			pr_cont(",compress");384		pr_cont("\n");385	}386	for (i = 0; i < 2; i++) {387		unsigned int dcr = i ? priv->dcr_cache : readb(priv->regs.dcr);388		printk(KERN_DEBUG PPIP32 "    dcr(%s)=0x%02x",389		       i ? "soft" : "hard", dcr);390		pr_cont(" %s", (dcr & DCR_DIR) ? "rev" : "fwd");391		if (dcr & DCR_IRQ)392			pr_cont(",ackIntEn");393		if (!(dcr & DCR_SELECT))394			pr_cont(",nSelectIn");395		if (dcr & DCR_nINIT)396			pr_cont(",nInit");397		if (!(dcr & DCR_AUTOFD))398			pr_cont(",nAutoFD");399		if (!(dcr & DCR_STROBE))400			pr_cont(",nStrobe");401		pr_cont("\n");402	}403#define sep (f++ ? ',' : ' ')404	{405		unsigned int f = 0;406		unsigned int dsr = readb(priv->regs.dsr);407		printk(KERN_DEBUG PPIP32 "    dsr=0x%02x", dsr);408		if (!(dsr & DSR_nBUSY))409			pr_cont("%cBusy", sep);410		if (dsr & DSR_nACK)411			pr_cont("%cnAck", sep);412		if (dsr & DSR_PERROR)413			pr_cont("%cPError", sep);414		if (dsr & DSR_SELECT)415			pr_cont("%cSelect", sep);416		if (dsr & DSR_nFAULT)417			pr_cont("%cnFault", sep);418		if (!(dsr & DSR_nPRINT))419			pr_cont("%c(Print)", sep);420		if (dsr & DSR_TIMEOUT)421			pr_cont("%cTimeout", sep);422		pr_cont("\n");423	}424#undef sep425}426#else /* DEBUG_PARPORT_IP32 < 2 */427#define parport_ip32_dump_state(...)	do { } while (0)428#endif429 430/*431 * CHECK_EXTRA_BITS - track and log extra bits432 * @p:		pointer to &struct parport433 * @b:		byte to inspect434 * @m:		bit mask of authorized bits435 *436 * This is used to track and log extra bits that should not be there in437 * parport_ip32_write_control() and parport_ip32_frob_control().  It is only438 * defined if %DEBUG_PARPORT_IP32 >= 1.439 */440#if DEBUG_PARPORT_IP32 >= 1441#define CHECK_EXTRA_BITS(p, b, m)					\442	do {								\443		unsigned int __b = (b), __m = (m);			\444		if (__b & ~__m)						\445			pr_debug1(PPIP32 "%s: extra bits in %s(%s): "	\446				  "0x%02x/0x%02x\n",			\447				  (p)->name, __func__, #b, __b, __m);	\448	} while (0)449#else /* DEBUG_PARPORT_IP32 < 1 */450#define CHECK_EXTRA_BITS(...)	do { } while (0)451#endif452 453/*--- IP32 parallel port DMA operations --------------------------------*/454 455/**456 * struct parport_ip32_dma_data - private data needed for DMA operation457 * @dir:	DMA direction (from or to device)458 * @buf:	buffer physical address459 * @len:	buffer length460 * @next:	address of next bytes to DMA transfer461 * @left:	number of bytes remaining462 * @ctx:	next context to write (0: context_a; 1: context_b)463 * @irq_on:	are the DMA IRQs currently enabled?464 * @lock:	spinlock to protect access to the structure465 */466struct parport_ip32_dma_data {467	enum dma_data_direction		dir;468	dma_addr_t			buf;469	dma_addr_t			next;470	size_t				len;471	size_t				left;472	unsigned int			ctx;473	unsigned int			irq_on;474	spinlock_t			lock;475};476static struct parport_ip32_dma_data parport_ip32_dma;477 478/**479 * parport_ip32_dma_setup_context - setup next DMA context480 * @limit:	maximum data size for the context481 *482 * The alignment constraints must be verified in caller function, and the483 * parameter @limit must be set accordingly.484 */485static void parport_ip32_dma_setup_context(unsigned int limit)486{487	unsigned long flags;488 489	spin_lock_irqsave(&parport_ip32_dma.lock, flags);490	if (parport_ip32_dma.left > 0) {491		/* Note: ctxreg is "volatile" here only because492		 * mace->perif.ctrl.parport.context_a and context_b are493		 * "volatile".  */494		volatile u64 __iomem *ctxreg = (parport_ip32_dma.ctx == 0) ?495			&mace->perif.ctrl.parport.context_a :496			&mace->perif.ctrl.parport.context_b;497		u64 count;498		u64 ctxval;499		if (parport_ip32_dma.left <= limit) {500			count = parport_ip32_dma.left;501			ctxval = MACEPAR_CONTEXT_LASTFLAG;502		} else {503			count = limit;504			ctxval = 0;505		}506 507		pr_trace(NULL,508			 "(%u): 0x%04x:0x%04x, %u -> %u%s",509			 limit,510			 (unsigned int)parport_ip32_dma.buf,511			 (unsigned int)parport_ip32_dma.next,512			 (unsigned int)count,513			 parport_ip32_dma.ctx, ctxval ? "*" : "");514 515		ctxval |= parport_ip32_dma.next &516			MACEPAR_CONTEXT_BASEADDR_MASK;517		ctxval |= ((count - 1) << MACEPAR_CONTEXT_DATALEN_SHIFT) &518			MACEPAR_CONTEXT_DATALEN_MASK;519		writeq(ctxval, ctxreg);520		parport_ip32_dma.next += count;521		parport_ip32_dma.left -= count;522		parport_ip32_dma.ctx ^= 1U;523	}524	/* If there is nothing more to send, disable IRQs to avoid to525	 * face an IRQ storm which can lock the machine.  Disable them526	 * only once. */527	if (parport_ip32_dma.left == 0 && parport_ip32_dma.irq_on) {528		pr_debug(PPIP32 "IRQ off (ctx)\n");529		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);530		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);531		parport_ip32_dma.irq_on = 0;532	}533	spin_unlock_irqrestore(&parport_ip32_dma.lock, flags);534}535 536/**537 * parport_ip32_dma_interrupt - DMA interrupt handler538 * @irq:	interrupt number539 * @dev_id:	unused540 */541static irqreturn_t parport_ip32_dma_interrupt(int irq, void *dev_id)542{543	if (parport_ip32_dma.left)544		pr_trace(NULL, "(%d): ctx=%d", irq, parport_ip32_dma.ctx);545	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);546	return IRQ_HANDLED;547}548 549#if DEBUG_PARPORT_IP32550static irqreturn_t parport_ip32_merr_interrupt(int irq, void *dev_id)551{552	pr_trace1(NULL, "(%d)", irq);553	return IRQ_HANDLED;554}555#endif556 557/**558 * parport_ip32_dma_start - begins a DMA transfer559 * @p:		partport to work on560 * @dir:	DMA direction: DMA_TO_DEVICE or DMA_FROM_DEVICE561 * @addr:	pointer to data buffer562 * @count:	buffer size563 *564 * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be565 * correctly balanced.566 */567static int parport_ip32_dma_start(struct parport *p,568		enum dma_data_direction dir, void *addr, size_t count)569{570	unsigned int limit;571	u64 ctrl;572 573	pr_trace(NULL, "(%d, %lu)", dir, (unsigned long)count);574 575	/* FIXME - add support for DMA_FROM_DEVICE.  In this case, buffer must576	 * be 64 bytes aligned. */577	BUG_ON(dir != DMA_TO_DEVICE);578 579	/* Reset DMA controller */580	ctrl = MACEPAR_CTLSTAT_RESET;581	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);582 583	/* DMA IRQs should normally be enabled */584	if (!parport_ip32_dma.irq_on) {585		WARN_ON(1);586		enable_irq(MACEISA_PAR_CTXA_IRQ);587		enable_irq(MACEISA_PAR_CTXB_IRQ);588		parport_ip32_dma.irq_on = 1;589	}590 591	/* Prepare DMA pointers */592	parport_ip32_dma.dir = dir;593	parport_ip32_dma.buf = dma_map_single(&p->bus_dev, addr, count, dir);594	parport_ip32_dma.len = count;595	parport_ip32_dma.next = parport_ip32_dma.buf;596	parport_ip32_dma.left = parport_ip32_dma.len;597	parport_ip32_dma.ctx = 0;598 599	/* Setup DMA direction and first two contexts */600	ctrl = (dir == DMA_TO_DEVICE) ? 0 : MACEPAR_CTLSTAT_DIRECTION;601	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);602	/* Single transfer should not cross a 4K page boundary */603	limit = MACEPAR_CONTEXT_DATA_BOUND -604		(parport_ip32_dma.next & (MACEPAR_CONTEXT_DATA_BOUND - 1));605	parport_ip32_dma_setup_context(limit);606	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);607 608	/* Real start of DMA transfer */609	ctrl |= MACEPAR_CTLSTAT_ENABLE;610	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);611 612	return 0;613}614 615/**616 * parport_ip32_dma_stop - ends a running DMA transfer617 * @p:		partport to work on618 *619 * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be620 * correctly balanced.621 */622static void parport_ip32_dma_stop(struct parport *p)623{624	u64 ctx_a;625	u64 ctx_b;626	u64 ctrl;627	u64 diag;628	size_t res[2];	/* {[0] = res_a, [1] = res_b} */629 630	pr_trace(NULL, "()");631 632	/* Disable IRQs */633	spin_lock_irq(&parport_ip32_dma.lock);634	if (parport_ip32_dma.irq_on) {635		pr_debug(PPIP32 "IRQ off (stop)\n");636		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);637		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);638		parport_ip32_dma.irq_on = 0;639	}640	spin_unlock_irq(&parport_ip32_dma.lock);641	/* Force IRQ synchronization, even if the IRQs were disabled642	 * elsewhere. */643	synchronize_irq(MACEISA_PAR_CTXA_IRQ);644	synchronize_irq(MACEISA_PAR_CTXB_IRQ);645 646	/* Stop DMA transfer */647	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);648	ctrl &= ~MACEPAR_CTLSTAT_ENABLE;649	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);650 651	/* Adjust residue (parport_ip32_dma.left) */652	ctx_a = readq(&mace->perif.ctrl.parport.context_a);653	ctx_b = readq(&mace->perif.ctrl.parport.context_b);654	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);655	diag = readq(&mace->perif.ctrl.parport.diagnostic);656	res[0] = (ctrl & MACEPAR_CTLSTAT_CTXA_VALID) ?657		1 + ((ctx_a & MACEPAR_CONTEXT_DATALEN_MASK) >>658		     MACEPAR_CONTEXT_DATALEN_SHIFT) :659		0;660	res[1] = (ctrl & MACEPAR_CTLSTAT_CTXB_VALID) ?661		1 + ((ctx_b & MACEPAR_CONTEXT_DATALEN_MASK) >>662		     MACEPAR_CONTEXT_DATALEN_SHIFT) :663		0;664	if (diag & MACEPAR_DIAG_DMACTIVE)665		res[(diag & MACEPAR_DIAG_CTXINUSE) != 0] =666			1 + ((diag & MACEPAR_DIAG_CTRMASK) >>667			     MACEPAR_DIAG_CTRSHIFT);668	parport_ip32_dma.left += res[0] + res[1];669 670	/* Reset DMA controller, and re-enable IRQs */671	ctrl = MACEPAR_CTLSTAT_RESET;672	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);673	pr_debug(PPIP32 "IRQ on (stop)\n");674	enable_irq(MACEISA_PAR_CTXA_IRQ);675	enable_irq(MACEISA_PAR_CTXB_IRQ);676	parport_ip32_dma.irq_on = 1;677 678	dma_unmap_single(&p->bus_dev, parport_ip32_dma.buf,679			 parport_ip32_dma.len, parport_ip32_dma.dir);680}681 682/**683 * parport_ip32_dma_get_residue - get residue from last DMA transfer684 *685 * Returns the number of bytes remaining from last DMA transfer.686 */687static inline size_t parport_ip32_dma_get_residue(void)688{689	return parport_ip32_dma.left;690}691 692/**693 * parport_ip32_dma_register - initialize DMA engine694 *695 * Returns zero for success.696 */697static int parport_ip32_dma_register(void)698{699	int err;700 701	spin_lock_init(&parport_ip32_dma.lock);702	parport_ip32_dma.irq_on = 1;703 704	/* Reset DMA controller */705	writeq(MACEPAR_CTLSTAT_RESET, &mace->perif.ctrl.parport.cntlstat);706 707	/* Request IRQs */708	err = request_irq(MACEISA_PAR_CTXA_IRQ, parport_ip32_dma_interrupt,709			  0, "parport_ip32", NULL);710	if (err)711		goto fail_a;712	err = request_irq(MACEISA_PAR_CTXB_IRQ, parport_ip32_dma_interrupt,713			  0, "parport_ip32", NULL);714	if (err)715		goto fail_b;716#if DEBUG_PARPORT_IP32717	/* FIXME - what is this IRQ for? */718	err = request_irq(MACEISA_PAR_MERR_IRQ, parport_ip32_merr_interrupt,719			  0, "parport_ip32", NULL);720	if (err)721		goto fail_merr;722#endif723	return 0;724 725#if DEBUG_PARPORT_IP32726fail_merr:727	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);728#endif729fail_b:730	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);731fail_a:732	return err;733}734 735/**736 * parport_ip32_dma_unregister - release and free resources for DMA engine737 */738static void parport_ip32_dma_unregister(void)739{740#if DEBUG_PARPORT_IP32741	free_irq(MACEISA_PAR_MERR_IRQ, NULL);742#endif743	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);744	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);745}746 747/*--- Interrupt handlers and associates --------------------------------*/748 749/**750 * parport_ip32_wakeup - wakes up code waiting for an interrupt751 * @p:		pointer to &struct parport752 */753static inline void parport_ip32_wakeup(struct parport *p)754{755	struct parport_ip32_private * const priv = p->physport->private_data;756	complete(&priv->irq_complete);757}758 759/**760 * parport_ip32_interrupt - interrupt handler761 * @irq:	interrupt number762 * @dev_id:	pointer to &struct parport763 *764 * Caught interrupts are forwarded to the upper parport layer if IRQ_mode is765 * %PARPORT_IP32_IRQ_FWD.766 */767static irqreturn_t parport_ip32_interrupt(int irq, void *dev_id)768{769	struct parport * const p = dev_id;770	struct parport_ip32_private * const priv = p->physport->private_data;771	enum parport_ip32_irq_mode irq_mode = priv->irq_mode;772 773	switch (irq_mode) {774	case PARPORT_IP32_IRQ_FWD:775		return parport_irq_handler(irq, dev_id);776 777	case PARPORT_IP32_IRQ_HERE:778		parport_ip32_wakeup(p);779		break;780	}781 782	return IRQ_HANDLED;783}784 785/*--- Some utility function to manipulate ECR register -----------------*/786 787/**788 * parport_ip32_read_econtrol - read contents of the ECR register789 * @p:		pointer to &struct parport790 */791static inline unsigned int parport_ip32_read_econtrol(struct parport *p)792{793	struct parport_ip32_private * const priv = p->physport->private_data;794	return readb(priv->regs.ecr);795}796 797/**798 * parport_ip32_write_econtrol - write new contents to the ECR register799 * @p:		pointer to &struct parport800 * @c:		new value to write801 */802static inline void parport_ip32_write_econtrol(struct parport *p,803					       unsigned int c)804{805	struct parport_ip32_private * const priv = p->physport->private_data;806	writeb(c, priv->regs.ecr);807}808 809/**810 * parport_ip32_frob_econtrol - change bits from the ECR register811 * @p:		pointer to &struct parport812 * @mask:	bit mask of bits to change813 * @val:	new value for changed bits814 *815 * Read from the ECR, mask out the bits in @mask, exclusive-or with the bits816 * in @val, and write the result to the ECR.817 */818static inline void parport_ip32_frob_econtrol(struct parport *p,819					      unsigned int mask,820					      unsigned int val)821{822	unsigned int c;823	c = (parport_ip32_read_econtrol(p) & ~mask) ^ val;824	parport_ip32_write_econtrol(p, c);825}826 827/**828 * parport_ip32_set_mode - change mode of ECP port829 * @p:		pointer to &struct parport830 * @mode:	new mode to write in ECR831 *832 * ECR is reset in a sane state (interrupts and DMA disabled), and placed in833 * mode @mode.  Go through PS2 mode if needed.834 */835static void parport_ip32_set_mode(struct parport *p, unsigned int mode)836{837	unsigned int omode;838 839	mode &= ECR_MODE_MASK;840	omode = parport_ip32_read_econtrol(p) & ECR_MODE_MASK;841 842	if (!(mode == ECR_MODE_SPP || mode == ECR_MODE_PS2843	      || omode == ECR_MODE_SPP || omode == ECR_MODE_PS2)) {844		/* We have to go through PS2 mode */845		unsigned int ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;846		parport_ip32_write_econtrol(p, ecr);847	}848	parport_ip32_write_econtrol(p, mode | ECR_nERRINTR | ECR_SERVINTR);849}850 851/*--- Basic functions needed for parport -------------------------------*/852 853/**854 * parport_ip32_read_data - return current contents of the DATA register855 * @p:		pointer to &struct parport856 */857static inline unsigned char parport_ip32_read_data(struct parport *p)858{859	struct parport_ip32_private * const priv = p->physport->private_data;860	return readb(priv->regs.data);861}862 863/**864 * parport_ip32_write_data - set new contents for the DATA register865 * @p:		pointer to &struct parport866 * @d:		new value to write867 */868static inline void parport_ip32_write_data(struct parport *p, unsigned char d)869{870	struct parport_ip32_private * const priv = p->physport->private_data;871	writeb(d, priv->regs.data);872}873 874/**875 * parport_ip32_read_status - return current contents of the DSR register876 * @p:		pointer to &struct parport877 */878static inline unsigned char parport_ip32_read_status(struct parport *p)879{880	struct parport_ip32_private * const priv = p->physport->private_data;881	return readb(priv->regs.dsr);882}883 884/**885 * __parport_ip32_read_control - return cached contents of the DCR register886 * @p:		pointer to &struct parport887 */888static inline unsigned int __parport_ip32_read_control(struct parport *p)889{890	struct parport_ip32_private * const priv = p->physport->private_data;891	return priv->dcr_cache; /* use soft copy */892}893 894/**895 * __parport_ip32_write_control - set new contents for the DCR register896 * @p:		pointer to &struct parport897 * @c:		new value to write898 */899static inline void __parport_ip32_write_control(struct parport *p,900						unsigned int c)901{902	struct parport_ip32_private * const priv = p->physport->private_data;903	CHECK_EXTRA_BITS(p, c, priv->dcr_writable);904	c &= priv->dcr_writable; /* only writable bits */905	writeb(c, priv->regs.dcr);906	priv->dcr_cache = c;		/* update soft copy */907}908 909/**910 * __parport_ip32_frob_control - change bits from the DCR register911 * @p:		pointer to &struct parport912 * @mask:	bit mask of bits to change913 * @val:	new value for changed bits914 *915 * This is equivalent to read from the DCR, mask out the bits in @mask,916 * exclusive-or with the bits in @val, and write the result to the DCR.917 * Actually, the cached contents of the DCR is used.918 */919static inline void __parport_ip32_frob_control(struct parport *p,920					       unsigned int mask,921					       unsigned int val)922{923	unsigned int c;924	c = (__parport_ip32_read_control(p) & ~mask) ^ val;925	__parport_ip32_write_control(p, c);926}927 928/**929 * parport_ip32_read_control - return cached contents of the DCR register930 * @p:		pointer to &struct parport931 *932 * The return value is masked so as to only return the value of %DCR_STROBE,933 * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.934 */935static inline unsigned char parport_ip32_read_control(struct parport *p)936{937	const unsigned int rm =938		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;939	return __parport_ip32_read_control(p) & rm;940}941 942/**943 * parport_ip32_write_control - set new contents for the DCR register944 * @p:		pointer to &struct parport945 * @c:		new value to write946 *947 * The value is masked so as to only change the value of %DCR_STROBE,948 * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.949 */950static inline void parport_ip32_write_control(struct parport *p,951					      unsigned char c)952{953	const unsigned int wm =954		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;955	CHECK_EXTRA_BITS(p, c, wm);956	__parport_ip32_frob_control(p, wm, c & wm);957}958 959/**960 * parport_ip32_frob_control - change bits from the DCR register961 * @p:		pointer to &struct parport962 * @mask:	bit mask of bits to change963 * @val:	new value for changed bits964 *965 * This differs from __parport_ip32_frob_control() in that it only allows to966 * change the value of %DCR_STROBE, %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.967 */968static inline unsigned char parport_ip32_frob_control(struct parport *p,969						      unsigned char mask,970						      unsigned char val)971{972	const unsigned int wm =973		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;974	CHECK_EXTRA_BITS(p, mask, wm);975	CHECK_EXTRA_BITS(p, val, wm);976	__parport_ip32_frob_control(p, mask & wm, val & wm);977	return parport_ip32_read_control(p);978}979 980/**981 * parport_ip32_disable_irq - disable interrupts on the rising edge of nACK982 * @p:		pointer to &struct parport983 */984static inline void parport_ip32_disable_irq(struct parport *p)985{986	__parport_ip32_frob_control(p, DCR_IRQ, 0);987}988 989/**990 * parport_ip32_enable_irq - enable interrupts on the rising edge of nACK991 * @p:		pointer to &struct parport992 */993static inline void parport_ip32_enable_irq(struct parport *p)994{995	__parport_ip32_frob_control(p, DCR_IRQ, DCR_IRQ);996}997 998/**999 * parport_ip32_data_forward - enable host-to-peripheral communications1000 * @p:		pointer to &struct parport1001 *1002 * Enable the data line drivers, for 8-bit host-to-peripheral communications.1003 */1004static inline void parport_ip32_data_forward(struct parport *p)1005{1006	__parport_ip32_frob_control(p, DCR_DIR, 0);1007}1008 1009/**1010 * parport_ip32_data_reverse - enable peripheral-to-host communications1011 * @p:		pointer to &struct parport1012 *1013 * Place the data bus in a high impedance state, if @p->modes has the1014 * PARPORT_MODE_TRISTATE bit set.1015 */1016static inline void parport_ip32_data_reverse(struct parport *p)1017{1018	__parport_ip32_frob_control(p, DCR_DIR, DCR_DIR);1019}1020 1021/**1022 * parport_ip32_init_state - for core parport code1023 * @dev:	pointer to &struct pardevice1024 * @s:		pointer to &struct parport_state to initialize1025 */1026static void parport_ip32_init_state(struct pardevice *dev,1027				    struct parport_state *s)1028{1029	s->u.ip32.dcr = DCR_SELECT | DCR_nINIT;1030	s->u.ip32.ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;1031}1032 1033/**1034 * parport_ip32_save_state - for core parport code1035 * @p:		pointer to &struct parport1036 * @s:		pointer to &struct parport_state to save state to1037 */1038static void parport_ip32_save_state(struct parport *p,1039				    struct parport_state *s)1040{1041	s->u.ip32.dcr = __parport_ip32_read_control(p);1042	s->u.ip32.ecr = parport_ip32_read_econtrol(p);1043}1044 1045/**1046 * parport_ip32_restore_state - for core parport code1047 * @p:		pointer to &struct parport1048 * @s:		pointer to &struct parport_state to restore state from1049 */1050static void parport_ip32_restore_state(struct parport *p,1051				       struct parport_state *s)1052{1053	parport_ip32_set_mode(p, s->u.ip32.ecr & ECR_MODE_MASK);1054	parport_ip32_write_econtrol(p, s->u.ip32.ecr);1055	__parport_ip32_write_control(p, s->u.ip32.dcr);1056}1057 1058/*--- EPP mode functions -----------------------------------------------*/1059 1060/**1061 * parport_ip32_clear_epp_timeout - clear Timeout bit in EPP mode1062 * @p:		pointer to &struct parport1063 *1064 * Returns 1 if the Timeout bit is clear, and 0 otherwise.1065 */1066static unsigned int parport_ip32_clear_epp_timeout(struct parport *p)1067{1068	struct parport_ip32_private * const priv = p->physport->private_data;1069	unsigned int cleared;1070 1071	if (!(parport_ip32_read_status(p) & DSR_TIMEOUT))1072		cleared = 1;1073	else {1074		unsigned int r;1075		/* To clear timeout some chips require double read */1076		parport_ip32_read_status(p);1077		r = parport_ip32_read_status(p);1078		/* Some reset by writing 1 */1079		writeb(r | DSR_TIMEOUT, priv->regs.dsr);1080		/* Others by writing 0 */1081		writeb(r & ~DSR_TIMEOUT, priv->regs.dsr);1082 1083		r = parport_ip32_read_status(p);1084		cleared = !(r & DSR_TIMEOUT);1085	}1086 1087	pr_trace(p, "(): %s", cleared ? "cleared" : "failed");1088	return cleared;1089}1090 1091/**1092 * parport_ip32_epp_read - generic EPP read function1093 * @eppreg:	I/O register to read from1094 * @p:		pointer to &struct parport1095 * @buf:	buffer to store read data1096 * @len:	length of buffer @buf1097 * @flags:	may be PARPORT_EPP_FAST1098 */1099static size_t parport_ip32_epp_read(void __iomem *eppreg,1100				    struct parport *p, void *buf,1101				    size_t len, int flags)1102{1103	struct parport_ip32_private * const priv = p->physport->private_data;1104	size_t got;1105	parport_ip32_set_mode(p, ECR_MODE_EPP);1106	parport_ip32_data_reverse(p);1107	parport_ip32_write_control(p, DCR_nINIT);1108	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {1109		readsb(eppreg, buf, len);1110		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {1111			parport_ip32_clear_epp_timeout(p);1112			return -EIO;1113		}1114		got = len;1115	} else {1116		u8 *bufp = buf;1117		for (got = 0; got < len; got++) {1118			*bufp++ = readb(eppreg);1119			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {1120				parport_ip32_clear_epp_timeout(p);1121				break;1122			}1123		}1124	}1125	parport_ip32_data_forward(p);1126	parport_ip32_set_mode(p, ECR_MODE_PS2);1127	return got;1128}1129 1130/**1131 * parport_ip32_epp_write - generic EPP write function1132 * @eppreg:	I/O register to write to1133 * @p:		pointer to &struct parport1134 * @buf:	buffer of data to write1135 * @len:	length of buffer @buf1136 * @flags:	may be PARPORT_EPP_FAST1137 */1138static size_t parport_ip32_epp_write(void __iomem *eppreg,1139				     struct parport *p, const void *buf,1140				     size_t len, int flags)1141{1142	struct parport_ip32_private * const priv = p->physport->private_data;1143	size_t written;1144	parport_ip32_set_mode(p, ECR_MODE_EPP);1145	parport_ip32_data_forward(p);1146	parport_ip32_write_control(p, DCR_nINIT);1147	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {1148		writesb(eppreg, buf, len);1149		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {1150			parport_ip32_clear_epp_timeout(p);1151			return -EIO;1152		}1153		written = len;1154	} else {1155		const u8 *bufp = buf;1156		for (written = 0; written < len; written++) {1157			writeb(*bufp++, eppreg);1158			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {1159				parport_ip32_clear_epp_timeout(p);1160				break;1161			}1162		}1163	}1164	parport_ip32_set_mode(p, ECR_MODE_PS2);1165	return written;1166}1167 1168/**1169 * parport_ip32_epp_read_data - read a block of data in EPP mode1170 * @p:		pointer to &struct parport1171 * @buf:	buffer to store read data1172 * @len:	length of buffer @buf1173 * @flags:	may be PARPORT_EPP_FAST1174 */1175static size_t parport_ip32_epp_read_data(struct parport *p, void *buf,1176					 size_t len, int flags)1177{1178	struct parport_ip32_private * const priv = p->physport->private_data;1179	return parport_ip32_epp_read(priv->regs.eppData0, p, buf, len, flags);1180}1181 1182/**1183 * parport_ip32_epp_write_data - write a block of data in EPP mode1184 * @p:		pointer to &struct parport1185 * @buf:	buffer of data to write1186 * @len:	length of buffer @buf1187 * @flags:	may be PARPORT_EPP_FAST1188 */1189static size_t parport_ip32_epp_write_data(struct parport *p, const void *buf,1190					  size_t len, int flags)1191{1192	struct parport_ip32_private * const priv = p->physport->private_data;1193	return parport_ip32_epp_write(priv->regs.eppData0, p, buf, len, flags);1194}1195 1196/**1197 * parport_ip32_epp_read_addr - read a block of addresses in EPP mode1198 * @p:		pointer to &struct parport1199 * @buf:	buffer to store read data1200 * @len:	length of buffer @buf1201 * @flags:	may be PARPORT_EPP_FAST1202 */1203static size_t parport_ip32_epp_read_addr(struct parport *p, void *buf,1204					 size_t len, int flags)1205{1206	struct parport_ip32_private * const priv = p->physport->private_data;1207	return parport_ip32_epp_read(priv->regs.eppAddr, p, buf, len, flags);1208}1209 1210/**1211 * parport_ip32_epp_write_addr - write a block of addresses in EPP mode1212 * @p:		pointer to &struct parport1213 * @buf:	buffer of data to write1214 * @len:	length of buffer @buf1215 * @flags:	may be PARPORT_EPP_FAST1216 */1217static size_t parport_ip32_epp_write_addr(struct parport *p, const void *buf,1218					  size_t len, int flags)1219{1220	struct parport_ip32_private * const priv = p->physport->private_data;1221	return parport_ip32_epp_write(priv->regs.eppAddr, p, buf, len, flags);1222}1223 1224/*--- ECP mode functions (FIFO) ----------------------------------------*/1225 1226/**1227 * parport_ip32_fifo_wait_break - check if the waiting function should return1228 * @p:		pointer to &struct parport1229 * @expire:	timeout expiring date, in jiffies1230 *1231 * parport_ip32_fifo_wait_break() checks if the waiting function should return1232 * immediately or not.  The break conditions are:1233 *	- expired timeout;1234 *	- a pending signal;1235 *	- nFault asserted low.1236 * This function also calls cond_resched().1237 */1238static unsigned int parport_ip32_fifo_wait_break(struct parport *p,1239						 unsigned long expire)1240{1241	cond_resched();1242	if (time_after(jiffies, expire)) {1243		pr_debug1(PPIP32 "%s: FIFO write timed out\n", p->name);1244		return 1;1245	}1246	if (signal_pending(current)) {1247		pr_debug1(PPIP32 "%s: Signal pending\n", p->name);1248		return 1;1249	}1250	if (!(parport_ip32_read_status(p) & DSR_nFAULT)) {1251		pr_debug1(PPIP32 "%s: nFault asserted low\n", p->name);1252		return 1;1253	}1254	return 0;1255}1256 1257/**1258 * parport_ip32_fwp_wait_polling - wait for FIFO to empty (polling)1259 * @p:		pointer to &struct parport1260 *1261 * Returns the number of bytes that can safely be written in the FIFO.  A1262 * return value of zero means that the calling function should terminate as1263 * fast as possible.1264 */1265static unsigned int parport_ip32_fwp_wait_polling(struct parport *p)1266{1267	struct parport_ip32_private * const priv = p->physport->private_data;1268	struct parport * const physport = p->physport;1269	unsigned long expire;1270	unsigned int count;1271	unsigned int ecr;1272 1273	expire = jiffies + physport->cad->timeout;1274	count = 0;1275	while (1) {1276		if (parport_ip32_fifo_wait_break(p, expire))1277			break;1278 1279		/* Check FIFO state.  We do nothing when the FIFO is nor full,1280		 * nor empty.  It appears that the FIFO full bit is not always1281		 * reliable, the FIFO state is sometimes wrongly reported, and1282		 * the chip gets confused if we give it another byte. */1283		ecr = parport_ip32_read_econtrol(p);1284		if (ecr & ECR_F_EMPTY) {1285			/* FIFO is empty, fill it up */1286			count = priv->fifo_depth;1287			break;1288		}1289 1290		/* Wait a moment... */1291		udelay(FIFO_POLLING_INTERVAL);1292	} /* while (1) */1293 1294	return count;1295}1296 1297/**1298 * parport_ip32_fwp_wait_interrupt - wait for FIFO to empty (interrupt-driven)1299 * @p:		pointer to &struct parport1300 *1301 * Returns the number of bytes that can safely be written in the FIFO.  A1302 * return value of zero means that the calling function should terminate as1303 * fast as possible.1304 */1305static unsigned int parport_ip32_fwp_wait_interrupt(struct parport *p)1306{1307	static unsigned int lost_interrupt = 0;1308	struct parport_ip32_private * const priv = p->physport->private_data;1309	struct parport * const physport = p->physport;1310	unsigned long nfault_timeout;1311	unsigned long expire;1312	unsigned int count;1313	unsigned int ecr;1314 1315	nfault_timeout = min((unsigned long)physport->cad->timeout,1316			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));1317	expire = jiffies + physport->cad->timeout;1318	count = 0;1319	while (1) {1320		if (parport_ip32_fifo_wait_break(p, expire))1321			break;1322 1323		/* Initialize mutex used to take interrupts into account */1324		reinit_completion(&priv->irq_complete);1325 1326		/* Enable serviceIntr */1327		parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);1328 1329		/* Enabling serviceIntr while the FIFO is empty does not1330		 * always generate an interrupt, so check for emptiness1331		 * now. */1332		ecr = parport_ip32_read_econtrol(p);1333		if (!(ecr & ECR_F_EMPTY)) {1334			/* FIFO is not empty: wait for an interrupt or a1335			 * timeout to occur */1336			wait_for_completion_interruptible_timeout(1337				&priv->irq_complete, nfault_timeout);1338			ecr = parport_ip32_read_econtrol(p);1339			if ((ecr & ECR_F_EMPTY) && !(ecr & ECR_SERVINTR)1340			    && !lost_interrupt) {1341				pr_warn(PPIP32 "%s: lost interrupt in %s\n",1342					p->name, __func__);1343				lost_interrupt = 1;1344			}1345		}1346 1347		/* Disable serviceIntr */1348		parport_ip32_frob_econtrol(p, ECR_SERVINTR, ECR_SERVINTR);1349 1350		/* Check FIFO state */1351		if (ecr & ECR_F_EMPTY) {1352			/* FIFO is empty, fill it up */1353			count = priv->fifo_depth;1354			break;1355		} else if (ecr & ECR_SERVINTR) {1356			/* FIFO is not empty, but we know that can safely push1357			 * writeIntrThreshold bytes into it */1358			count = priv->writeIntrThreshold;1359			break;1360		}1361		/* FIFO is not empty, and we did not get any interrupt.1362		 * Either it's time to check for nFault, or a signal is1363		 * pending.  This is verified in1364		 * parport_ip32_fifo_wait_break(), so we continue the loop. */1365	} /* while (1) */1366 1367	return count;1368}1369 1370/**1371 * parport_ip32_fifo_write_block_pio - write a block of data (PIO mode)1372 * @p:		pointer to &struct parport1373 * @buf:	buffer of data to write1374 * @len:	length of buffer @buf1375 *1376 * Uses PIO to write the contents of the buffer @buf into the parallel port1377 * FIFO.  Returns the number of bytes that were actually written.  It can work1378 * with or without the help of interrupts.  The parallel port must be1379 * correctly initialized before calling parport_ip32_fifo_write_block_pio().1380 */1381static size_t parport_ip32_fifo_write_block_pio(struct parport *p,1382						const void *buf, size_t len)1383{1384	struct parport_ip32_private * const priv = p->physport->private_data;1385	const u8 *bufp = buf;1386	size_t left = len;1387 1388	priv->irq_mode = PARPORT_IP32_IRQ_HERE;1389 1390	while (left > 0) {1391		unsigned int count;1392 1393		count = (p->irq == PARPORT_IRQ_NONE) ?1394			parport_ip32_fwp_wait_polling(p) :1395			parport_ip32_fwp_wait_interrupt(p);1396		if (count == 0)1397			break;	/* Transmission should be stopped */1398		if (count > left)1399			count = left;1400		if (count == 1) {1401			writeb(*bufp, priv->regs.fifo);1402			bufp++, left--;1403		} else {1404			writesb(priv->regs.fifo, bufp, count);1405			bufp += count, left -= count;1406		}1407	}1408 1409	priv->irq_mode = PARPORT_IP32_IRQ_FWD;1410 1411	return len - left;1412}1413 1414/**1415 * parport_ip32_fifo_write_block_dma - write a block of data (DMA mode)1416 * @p:		pointer to &struct parport1417 * @buf:	buffer of data to write1418 * @len:	length of buffer @buf1419 *1420 * Uses DMA to write the contents of the buffer @buf into the parallel port1421 * FIFO.  Returns the number of bytes that were actually written.  The1422 * parallel port must be correctly initialized before calling1423 * parport_ip32_fifo_write_block_dma().1424 */1425static size_t parport_ip32_fifo_write_block_dma(struct parport *p,1426						const void *buf, size_t len)1427{1428	struct parport_ip32_private * const priv = p->physport->private_data;1429	struct parport * const physport = p->physport;1430	unsigned long nfault_timeout;1431	unsigned long expire;1432	size_t written;1433	unsigned int ecr;1434 1435	priv->irq_mode = PARPORT_IP32_IRQ_HERE;1436 1437	parport_ip32_dma_start(p, DMA_TO_DEVICE, (void *)buf, len);1438	reinit_completion(&priv->irq_complete);1439	parport_ip32_frob_econtrol(p, ECR_DMAEN | ECR_SERVINTR, ECR_DMAEN);1440 1441	nfault_timeout = min((unsigned long)physport->cad->timeout,1442			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));1443	expire = jiffies + physport->cad->timeout;1444	while (1) {1445		if (parport_ip32_fifo_wait_break(p, expire))1446			break;1447		wait_for_completion_interruptible_timeout(&priv->irq_complete,1448							  nfault_timeout);1449		ecr = parport_ip32_read_econtrol(p);1450		if (ecr & ECR_SERVINTR)1451			break;	/* DMA transfer just finished */1452	}1453	parport_ip32_dma_stop(p);1454	written = len - parport_ip32_dma_get_residue();1455 1456	priv->irq_mode = PARPORT_IP32_IRQ_FWD;1457 1458	return written;1459}1460 1461/**1462 * parport_ip32_fifo_write_block - write a block of data1463 * @p:		pointer to &struct parport1464 * @buf:	buffer of data to write1465 * @len:	length of buffer @buf1466 *1467 * Uses PIO or DMA to write the contents of the buffer @buf into the parallel1468 * p FIFO.  Returns the number of bytes that were actually written.1469 */1470static size_t parport_ip32_fifo_write_block(struct parport *p,1471					    const void *buf, size_t len)1472{1473	size_t written = 0;1474	if (len)1475		/* FIXME - Maybe some threshold value should be set for @len1476		 * under which we revert to PIO mode? */1477		written = (p->modes & PARPORT_MODE_DMA) ?1478			parport_ip32_fifo_write_block_dma(p, buf, len) :1479			parport_ip32_fifo_write_block_pio(p, buf, len);1480	return written;1481}1482 1483/**1484 * parport_ip32_drain_fifo - wait for FIFO to empty1485 * @p:		pointer to &struct parport1486 * @timeout:	timeout, in jiffies1487 *1488 * This function waits for FIFO to empty.  It returns 1 when FIFO is empty, or1489 * 0 if the timeout @timeout is reached before, or if a signal is pending.1490 */1491static unsigned int parport_ip32_drain_fifo(struct parport *p,1492					    unsigned long timeout)1493{1494	unsigned long expire = jiffies + timeout;1495	unsigned int polling_interval;1496	unsigned int counter;1497 1498	/* Busy wait for approx. 200us */1499	for (counter = 0; counter < 40; counter++) {1500		if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)1501			break;1502		if (time_after(jiffies, expire))1503			break;1504		if (signal_pending(current))1505			break;1506		udelay(5);1507	}1508	/* Poll slowly.  Polling interval starts with 1 millisecond, and is1509	 * increased exponentially until 128.  */1510	polling_interval = 1; /* msecs */1511	while (!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY)) {1512		if (time_after_eq(jiffies, expire))1513			break;1514		msleep_interruptible(polling_interval);1515		if (signal_pending(current))1516			break;1517		if (polling_interval < 128)1518			polling_interval *= 2;1519	}1520 1521	return !!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY);1522}1523 1524/**1525 * parport_ip32_get_fifo_residue - reset FIFO1526 * @p:		pointer to &struct parport1527 * @mode:	current operation mode (ECR_MODE_PPF or ECR_MODE_ECP)1528 *1529 * This function resets FIFO, and returns the number of bytes remaining in it.1530 */1531static unsigned int parport_ip32_get_fifo_residue(struct parport *p,1532						  unsigned int mode)1533{1534	struct parport_ip32_private * const priv = p->physport->private_data;1535	unsigned int residue;1536	unsigned int cnfga;1537 1538	/* FIXME - We are missing one byte if the printer is off-line.  I1539	 * don't know how to detect this.  It looks that the full bit is not1540	 * always reliable.  For the moment, the problem is avoided in most1541	 * cases by testing for BUSY in parport_ip32_compat_write_data().1542	 */1543	if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)1544		residue = 0;1545	else {1546		pr_debug1(PPIP32 "%s: FIFO is stuck\n", p->name);1547 1548		/* Stop all transfers.1549		 *1550		 * Microsoft's document instructs to drive DCR_STROBE to 0,1551		 * but it doesn't work (at least in Compatibility mode, not1552		 * tested in ECP mode).  Switching directly to Test mode (as1553		 * in parport_pc) is not an option: it does confuse the port,1554		 * ECP service interrupts are no more working after that.  A1555		 * hard reset is then needed to revert to a sane state.1556		 *1557		 * Let's hope that the FIFO is really stuck and that the1558		 * peripheral doesn't wake up now.1559		 */1560		parport_ip32_frob_control(p, DCR_STROBE, 0);1561 1562		/* Fill up FIFO */1563		for (residue = priv->fifo_depth; residue > 0; residue--) {1564			if (parport_ip32_read_econtrol(p) & ECR_F_FULL)1565				break;1566			writeb(0x00, priv->regs.fifo);1567		}1568	}1569	if (residue)1570		pr_debug1(PPIP32 "%s: %d PWord%s left in FIFO\n",1571			  p->name, residue,1572			  (residue == 1) ? " was" : "s were");1573 1574	/* Now reset the FIFO */1575	parport_ip32_set_mode(p, ECR_MODE_PS2);1576 1577	/* Host recovery for ECP mode */1578	if (mode == ECR_MODE_ECP) {1579		parport_ip32_data_reverse(p);1580		parport_ip32_frob_control(p, DCR_nINIT, 0);1581		if (parport_wait_peripheral(p, DSR_PERROR, 0))1582			pr_debug1(PPIP32 "%s: PEerror timeout 1 in %s\n",1583				  p->name, __func__);1584		parport_ip32_frob_control(p, DCR_STROBE, DCR_STROBE);1585		parport_ip32_frob_control(p, DCR_nINIT, DCR_nINIT);1586		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR))1587			pr_debug1(PPIP32 "%s: PEerror timeout 2 in %s\n",1588				  p->name, __func__);1589	}1590 1591	/* Adjust residue if needed */1592	parport_ip32_set_mode(p, ECR_MODE_CFG);1593	cnfga = readb(priv->regs.cnfgA);1594	if (!(cnfga & CNFGA_nBYTEINTRANS)) {1595		pr_debug1(PPIP32 "%s: cnfgA contains 0x%02x\n",1596			  p->name, cnfga);1597		pr_debug1(PPIP32 "%s: Accounting for extra byte\n",1598			  p->name);1599		residue++;1600	}1601 1602	/* Don't care about partial PWords since we do not support1603	 * PWord != 1 byte. */1604 1605	/* Back to forward PS2 mode. */1606	parport_ip32_set_mode(p, ECR_MODE_PS2);1607	parport_ip32_data_forward(p);1608 1609	return residue;1610}1611 1612/**1613 * parport_ip32_compat_write_data - write a block of data in SPP mode1614 * @p:		pointer to &struct parport1615 * @buf:	buffer of data to write1616 * @len:	length of buffer @buf1617 * @flags:	ignored1618 */1619static size_t parport_ip32_compat_write_data(struct parport *p,1620					     const void *buf, size_t len,1621					     int flags)1622{1623	static unsigned int ready_before = 1;1624	struct parport_ip32_private * const priv = p->physport->private_data;1625	struct parport * const physport = p->physport;1626	size_t written = 0;1627 1628	/* Special case: a timeout of zero means we cannot call schedule().1629	 * Also if O_NONBLOCK is set then use the default implementation. */1630	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)1631		return parport_ieee1284_write_compat(p, buf, len, flags);1632 1633	/* Reset FIFO, go in forward mode, and disable ackIntEn */1634	parport_ip32_set_mode(p, ECR_MODE_PS2);1635	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);1636	parport_ip32_data_forward(p);1637	parport_ip32_disable_irq(p);1638	parport_ip32_set_mode(p, ECR_MODE_PPF);1639	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;1640 1641	/* Wait for peripheral to become ready */1642	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,1643				       DSR_nBUSY | DSR_nFAULT)) {1644		/* Avoid to flood the logs */1645		if (ready_before)1646			pr_info(PPIP32 "%s: not ready in %s\n",1647				p->name, __func__);1648		ready_before = 0;1649		goto stop;1650	}1651	ready_before = 1;1652 1653	written = parport_ip32_fifo_write_block(p, buf, len);1654 1655	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */1656	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);1657 1658	/* Check for a potential residue */1659	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_PPF);1660 1661	/* Then, wait for BUSY to get low. */1662	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))1663		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",1664		       p->name, __func__);1665 1666stop:1667	/* Reset FIFO */1668	parport_ip32_set_mode(p, ECR_MODE_PS2);1669	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;1670 1671	return written;1672}1673 1674/*1675 * FIXME - Insert here parport_ip32_ecp_read_data().1676 */1677 1678/**1679 * parport_ip32_ecp_write_data - write a block of data in ECP mode1680 * @p:		pointer to &struct parport1681 * @buf:	buffer of data to write1682 * @len:	length of buffer @buf1683 * @flags:	ignored1684 */1685static size_t parport_ip32_ecp_write_data(struct parport *p,1686					  const void *buf, size_t len,1687					  int flags)1688{1689	static unsigned int ready_before = 1;1690	struct parport_ip32_private * const priv = p->physport->private_data;1691	struct parport * const physport = p->physport;1692	size_t written = 0;1693 1694	/* Special case: a timeout of zero means we cannot call schedule().1695	 * Also if O_NONBLOCK is set then use the default implementation. */1696	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)1697		return parport_ieee1284_ecp_write_data(p, buf, len, flags);1698 1699	/* Negotiate to forward mode if necessary. */1700	if (physport->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {1701		/* Event 47: Set nInit high. */1702		parport_ip32_frob_control(p, DCR_nINIT | DCR_AUTOFD,1703					     DCR_nINIT | DCR_AUTOFD);1704 1705		/* Event 49: PError goes high. */1706		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR)) {1707			printk(KERN_DEBUG PPIP32 "%s: PError timeout in %s\n",1708			       p->name, __func__);1709			physport->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;1710			return 0;1711		}1712	}1713 1714	/* Reset FIFO, go in forward mode, and disable ackIntEn */1715	parport_ip32_set_mode(p, ECR_MODE_PS2);1716	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);1717	parport_ip32_data_forward(p);1718	parport_ip32_disable_irq(p);1719	parport_ip32_set_mode(p, ECR_MODE_ECP);1720	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;1721 1722	/* Wait for peripheral to become ready */1723	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,1724				       DSR_nBUSY | DSR_nFAULT)) {1725		/* Avoid to flood the logs */1726		if (ready_before)1727			pr_info(PPIP32 "%s: not ready in %s\n",1728				p->name, __func__);1729		ready_before = 0;1730		goto stop;1731	}1732	ready_before = 1;1733 1734	written = parport_ip32_fifo_write_block(p, buf, len);1735 1736	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */1737	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);1738 1739	/* Check for a potential residue */1740	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_ECP);1741 1742	/* Then, wait for BUSY to get low. */1743	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))1744		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",1745		       p->name, __func__);1746 1747stop:1748	/* Reset FIFO */1749	parport_ip32_set_mode(p, ECR_MODE_PS2);1750	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;1751 1752	return written;1753}1754 1755/*1756 * FIXME - Insert here parport_ip32_ecp_write_addr().1757 */1758 1759/*--- Default parport operations ---------------------------------------*/1760 1761static const struct parport_operations parport_ip32_ops __initconst = {1762	.write_data		= parport_ip32_write_data,1763	.read_data		= parport_ip32_read_data,1764 1765	.write_control		= parport_ip32_write_control,1766	.read_control		= parport_ip32_read_control,1767	.frob_control		= parport_ip32_frob_control,1768 1769	.read_status		= parport_ip32_read_status,1770 1771	.enable_irq		= parport_ip32_enable_irq,1772	.disable_irq		= parport_ip32_disable_irq,1773 1774	.data_forward		= parport_ip32_data_forward,1775	.data_reverse		= parport_ip32_data_reverse,1776 1777	.init_state		= parport_ip32_init_state,1778	.save_state		= parport_ip32_save_state,1779	.restore_state		= parport_ip32_restore_state,1780 1781	.epp_write_data		= parport_ieee1284_epp_write_data,1782	.epp_read_data		= parport_ieee1284_epp_read_data,1783	.epp_write_addr		= parport_ieee1284_epp_write_addr,1784	.epp_read_addr		= parport_ieee1284_epp_read_addr,1785 1786	.ecp_write_data		= parport_ieee1284_ecp_write_data,1787	.ecp_read_data		= parport_ieee1284_ecp_read_data,1788	.ecp_write_addr		= parport_ieee1284_ecp_write_addr,1789 1790	.compat_write_data	= parport_ieee1284_write_compat,1791	.nibble_read_data	= parport_ieee1284_read_nibble,1792	.byte_read_data		= parport_ieee1284_read_byte,1793 1794	.owner			= THIS_MODULE,1795};1796 1797/*--- Device detection -------------------------------------------------*/1798 1799/**1800 * parport_ip32_ecp_supported - check for an ECP port1801 * @p:		pointer to the &parport structure1802 *1803 * Returns 1 if an ECP port is found, and 0 otherwise.  This function actually1804 * checks if an Extended Control Register seems to be present.  On successful1805 * return, the port is placed in SPP mode.1806 */1807static __init unsigned int parport_ip32_ecp_supported(struct parport *p)1808{1809	struct parport_ip32_private * const priv = p->physport->private_data;1810	unsigned int ecr;1811 1812	ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;1813	writeb(ecr, priv->regs.ecr);1814	if (readb(priv->regs.ecr) != (ecr | ECR_F_EMPTY))1815		goto fail;1816 1817	pr_probe(p, "Found working ECR register\n");1818	parport_ip32_set_mode(p, ECR_MODE_SPP);1819	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);1820	return 1;1821 1822fail:1823	pr_probe(p, "ECR register not found\n");1824	return 0;1825}1826 1827/**1828 * parport_ip32_fifo_supported - check for FIFO parameters1829 * @p:		pointer to the &parport structure1830 *1831 * Check for FIFO parameters of an Extended Capabilities Port.  Returns 1 on1832 * success, and 0 otherwise.  Adjust FIFO parameters in the parport structure.1833 * On return, the port is placed in SPP mode.1834 */1835static __init unsigned int parport_ip32_fifo_supported(struct parport *p)1836{1837	struct parport_ip32_private * const priv = p->physport->private_data;1838	unsigned int configa, configb;1839	unsigned int pword;1840	unsigned int i;1841 1842	/* Configuration mode */1843	parport_ip32_set_mode(p, ECR_MODE_CFG);1844	configa = readb(priv->regs.cnfgA);1845	configb = readb(priv->regs.cnfgB);1846 1847	/* Find out PWord size */1848	switch (configa & CNFGA_ID_MASK) {1849	case CNFGA_ID_8:1850		pword = 1;1851		break;1852	case CNFGA_ID_16:1853		pword = 2;1854		break;1855	case CNFGA_ID_32:1856		pword = 4;1857		break;1858	default:1859		pr_probe(p, "Unknown implementation ID: 0x%0x\n",1860			 (configa & CNFGA_ID_MASK) >> CNFGA_ID_SHIFT);1861		goto fail;1862		break;1863	}1864	if (pword != 1) {1865		pr_probe(p, "Unsupported PWord size: %u\n", pword);1866		goto fail;1867	}1868	priv->pword = pword;1869	pr_probe(p, "PWord is %u bits\n", 8 * priv->pword);1870 1871	/* Check for compression support */1872	writeb(configb | CNFGB_COMPRESS, priv->regs.cnfgB);1873	if (readb(priv->regs.cnfgB) & CNFGB_COMPRESS)1874		pr_probe(p, "Hardware compression detected (unsupported)\n");1875	writeb(configb & ~CNFGB_COMPRESS, priv->regs.cnfgB);1876 1877	/* Reset FIFO and go in test mode (no interrupt, no DMA) */1878	parport_ip32_set_mode(p, ECR_MODE_TST);1879 1880	/* FIFO must be empty now */1881	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {1882		pr_probe(p, "FIFO not reset\n");1883		goto fail;1884	}1885 1886	/* Find out FIFO depth. */1887	priv->fifo_depth = 0;1888	for (i = 0; i < 1024; i++) {1889		if (readb(priv->regs.ecr) & ECR_F_FULL) {1890			/* FIFO full */1891			priv->fifo_depth = i;1892			break;1893		}1894		writeb((u8)i, priv->regs.fifo);1895	}1896	if (i >= 1024) {1897		pr_probe(p, "Can't fill FIFO\n");1898		goto fail;1899	}1900	if (!priv->fifo_depth) {1901		pr_probe(p, "Can't get FIFO depth\n");1902		goto fail;1903	}1904	pr_probe(p, "FIFO is %u PWords deep\n", priv->fifo_depth);1905 1906	/* Enable interrupts */1907	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);1908 1909	/* Find out writeIntrThreshold: number of PWords we know we can write1910	 * if we get an interrupt. */1911	priv->writeIntrThreshold = 0;1912	for (i = 0; i < priv->fifo_depth; i++) {1913		if (readb(priv->regs.fifo) != (u8)i) {1914			pr_probe(p, "Invalid data in FIFO\n");1915			goto fail;1916		}1917		if (!priv->writeIntrThreshold1918		    && readb(priv->regs.ecr) & ECR_SERVINTR)1919			/* writeIntrThreshold reached */1920			priv->writeIntrThreshold = i + 1;1921		if (i + 1 < priv->fifo_depth1922		    && readb(priv->regs.ecr) & ECR_F_EMPTY) {1923			/* FIFO empty before the last byte? */1924			pr_probe(p, "Data lost in FIFO\n");1925			goto fail;1926		}1927	}1928	if (!priv->writeIntrThreshold) {1929		pr_probe(p, "Can't get writeIntrThreshold\n");1930		goto fail;1931	}1932	pr_probe(p, "writeIntrThreshold is %u\n", priv->writeIntrThreshold);1933 1934	/* FIFO must be empty now */1935	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {1936		pr_probe(p, "Can't empty FIFO\n");1937		goto fail;1938	}1939 1940	/* Reset FIFO */1941	parport_ip32_set_mode(p, ECR_MODE_PS2);1942	/* Set reverse direction (must be in PS2 mode) */1943	parport_ip32_data_reverse(p);1944	/* Test FIFO, no interrupt, no DMA */1945	parport_ip32_set_mode(p, ECR_MODE_TST);1946	/* Enable interrupts */1947	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);1948 1949	/* Find out readIntrThreshold: number of PWords we can read if we get1950	 * an interrupt. */1951	priv->readIntrThreshold = 0;1952	for (i = 0; i < priv->fifo_depth; i++) {1953		writeb(0xaa, priv->regs.fifo);1954		if (readb(priv->regs.ecr) & ECR_SERVINTR) {1955			/* readIntrThreshold reached */1956			priv->readIntrThreshold = i + 1;1957			break;1958		}1959	}1960	if (!priv->readIntrThreshold) {1961		pr_probe(p, "Can't get readIntrThreshold\n");1962		goto fail;1963	}1964	pr_probe(p, "readIntrThreshold is %u\n", priv->readIntrThreshold);1965 1966	/* Reset ECR */1967	parport_ip32_set_mode(p, ECR_MODE_PS2);1968	parport_ip32_data_forward(p);1969	parport_ip32_set_mode(p, ECR_MODE_SPP);1970	return 1;1971 1972fail:1973	priv->fifo_depth = 0;1974	parport_ip32_set_mode(p, ECR_MODE_SPP);1975	return 0;1976}1977 1978/*--- Initialization code ----------------------------------------------*/1979 1980/**1981 * parport_ip32_make_isa_registers - compute (ISA) register addresses1982 * @regs:	pointer to &struct parport_ip32_regs to fill1983 * @base:	base address of standard and EPP registers1984 * @base_hi:	base address of ECP registers1985 * @regshift:	how much to shift register offset by1986 *1987 * Compute register addresses, according to the ISA standard.  The addresses1988 * of the standard and EPP registers are computed from address @base.  The1989 * addresses of the ECP registers are computed from address @base_hi.1990 */1991static void __init1992parport_ip32_make_isa_registers(struct parport_ip32_regs *regs,1993				void __iomem *base, void __iomem *base_hi,1994				unsigned int regshift)1995{1996#define r_base(offset)    ((u8 __iomem *)base    + ((offset) << regshift))1997#define r_base_hi(offset) ((u8 __iomem *)base_hi + ((offset) << regshift))1998	*regs = (struct parport_ip32_regs){1999		.data		= r_base(0),2000		.dsr		= r_base(1),2001		.dcr		= r_base(2),2002		.eppAddr	= r_base(3),2003		.eppData0	= r_base(4),2004		.eppData1	= r_base(5),2005		.eppData2	= r_base(6),2006		.eppData3	= r_base(7),2007		.ecpAFifo	= r_base(0),2008		.fifo		= r_base_hi(0),2009		.cnfgA		= r_base_hi(0),2010		.cnfgB		= r_base_hi(1),2011		.ecr		= r_base_hi(2)2012	};2013#undef r_base_hi2014#undef r_base2015}2016 2017/**2018 * parport_ip32_probe_port - probe and register IP32 built-in parallel port2019 *2020 * Returns the new allocated &parport structure.  On error, an error code is2021 * encoded in return value with the ERR_PTR function.2022 */2023static __init struct parport *parport_ip32_probe_port(void)2024{2025	struct parport_ip32_regs regs;2026	struct parport_ip32_private *priv = NULL;2027	struct parport_operations *ops = NULL;2028	struct parport *p = NULL;2029	int err;2030 2031	parport_ip32_make_isa_registers(&regs, &mace->isa.parallel,2032					&mace->isa.ecp1284, 8 /* regshift */);2033 2034	ops = kmalloc(sizeof(struct parport_operations), GFP_KERNEL);2035	priv = kmalloc(sizeof(struct parport_ip32_private), GFP_KERNEL);2036	p = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, ops);2037	if (ops == NULL || priv == NULL || p == NULL) {2038		err = -ENOMEM;2039		goto fail;2040	}2041	p->base = MACE_BASE + offsetof(struct sgi_mace, isa.parallel);2042	p->base_hi = MACE_BASE + offsetof(struct sgi_mace, isa.ecp1284);2043	p->private_data = priv;2044 2045	*ops = parport_ip32_ops;2046	*priv = (struct parport_ip32_private){2047		.regs			= regs,2048		.dcr_writable		= DCR_DIR | DCR_SELECT | DCR_nINIT |2049					  DCR_AUTOFD | DCR_STROBE,2050		.irq_mode		= PARPORT_IP32_IRQ_FWD,2051	};2052	init_completion(&priv->irq_complete);2053 2054	/* Probe port. */2055	if (!parport_ip32_ecp_supported(p)) {2056		err = -ENODEV;2057		goto fail;2058	}2059	parport_ip32_dump_state(p, "begin init", 0);2060 2061	/* We found what looks like a working ECR register.  Simply assume2062	 * that all modes are correctly supported.  Enable basic modes. */2063	p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;2064	p->modes |= PARPORT_MODE_TRISTATE;2065 2066	if (!parport_ip32_fifo_supported(p)) {2067		pr_warn(PPIP32 "%s: error: FIFO disabled\n", p->name);2068		/* Disable hardware modes depending on a working FIFO. */2069		features &= ~PARPORT_IP32_ENABLE_SPP;2070		features &= ~PARPORT_IP32_ENABLE_ECP;2071		/* DMA is not needed if FIFO is not supported.  */2072		features &= ~PARPORT_IP32_ENABLE_DMA;2073	}2074 2075	/* Request IRQ */2076	if (features & PARPORT_IP32_ENABLE_IRQ) {2077		int irq = MACEISA_PARALLEL_IRQ;2078		if (request_irq(irq, parport_ip32_interrupt, 0, p->name, p)) {2079			pr_warn(PPIP32 "%s: error: IRQ disabled\n", p->name);2080			/* DMA cannot work without interrupts. */2081			features &= ~PARPORT_IP32_ENABLE_DMA;2082		} else {2083			pr_probe(p, "Interrupt support enabled\n");2084			p->irq = irq;2085			priv->dcr_writable |= DCR_IRQ;2086		}2087	}2088 2089	/* Allocate DMA resources */2090	if (features & PARPORT_IP32_ENABLE_DMA) {2091		if (parport_ip32_dma_register())2092			pr_warn(PPIP32 "%s: error: DMA disabled\n", p->name);2093		else {2094			pr_probe(p, "DMA support enabled\n");2095			p->dma = 0; /* arbitrary value != PARPORT_DMA_NONE */2096			p->modes |= PARPORT_MODE_DMA;2097		}2098	}2099 2100	if (features & PARPORT_IP32_ENABLE_SPP) {2101		/* Enable compatibility FIFO mode */2102		p->ops->compat_write_data = parport_ip32_compat_write_data;2103		p->modes |= PARPORT_MODE_COMPAT;2104		pr_probe(p, "Hardware support for SPP mode enabled\n");2105	}2106	if (features & PARPORT_IP32_ENABLE_EPP) {2107		/* Set up access functions to use EPP hardware. */2108		p->ops->epp_read_data = parport_ip32_epp_read_data;2109		p->ops->epp_write_data = parport_ip32_epp_write_data;2110		p->ops->epp_read_addr = parport_ip32_epp_read_addr;2111		p->ops->epp_write_addr = parport_ip32_epp_write_addr;2112		p->modes |= PARPORT_MODE_EPP;2113		pr_probe(p, "Hardware support for EPP mode enabled\n");2114	}2115	if (features & PARPORT_IP32_ENABLE_ECP) {2116		/* Enable ECP FIFO mode */2117		p->ops->ecp_write_data = parport_ip32_ecp_write_data;2118		/* FIXME - not implemented */2119/*		p->ops->ecp_read_data  = parport_ip32_ecp_read_data; */2120/*		p->ops->ecp_write_addr = parport_ip32_ecp_write_addr; */2121		p->modes |= PARPORT_MODE_ECP;2122		pr_probe(p, "Hardware support for ECP mode enabled\n");2123	}2124 2125	/* Initialize the port with sensible values */2126	parport_ip32_set_mode(p, ECR_MODE_PS2);2127	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);2128	parport_ip32_data_forward(p);2129	parport_ip32_disable_irq(p);2130	parport_ip32_write_data(p, 0x00);2131	parport_ip32_dump_state(p, "end init", 0);2132 2133	/* Print out what we found */2134	pr_info("%s: SGI IP32 at 0x%lx (0x%lx)", p->name, p->base, p->base_hi);2135	if (p->irq != PARPORT_IRQ_NONE)2136		pr_cont(", irq %d", p->irq);2137	pr_cont(" [");2138#define printmode(x)							\2139do {									\2140	if (p->modes & PARPORT_MODE_##x)				\2141		pr_cont("%s%s", f++ ? "," : "", #x);			\2142} while (0)2143	{2144		unsigned int f = 0;2145		printmode(PCSPP);2146		printmode(TRISTATE);2147		printmode(COMPAT);2148		printmode(EPP);2149		printmode(ECP);2150		printmode(DMA);2151	}2152#undef printmode2153	pr_cont("]\n");2154 2155	parport_announce_port(p);2156	return p;2157 2158fail:2159	if (p)2160		parport_put_port(p);2161	kfree(priv);2162	kfree(ops);2163	return ERR_PTR(err);2164}2165 2166/**2167 * parport_ip32_unregister_port - unregister a parallel port2168 * @p:		pointer to the &struct parport2169 *2170 * Unregisters a parallel port and free previously allocated resources2171 * (memory, IRQ, ...).2172 */2173static __exit void parport_ip32_unregister_port(struct parport *p)2174{2175	struct parport_ip32_private * const priv = p->physport->private_data;2176	struct parport_operations *ops = p->ops;2177 2178	parport_remove_port(p);2179	if (p->modes & PARPORT_MODE_DMA)2180		parport_ip32_dma_unregister();2181	if (p->irq != PARPORT_IRQ_NONE)2182		free_irq(p->irq, p);2183	parport_put_port(p);2184	kfree(priv);2185	kfree(ops);2186}2187 2188/**2189 * parport_ip32_init - module initialization function2190 */2191static int __init parport_ip32_init(void)2192{2193	pr_info(PPIP32 "SGI IP32 built-in parallel port driver v0.6\n");2194	this_port = parport_ip32_probe_port();2195	return PTR_ERR_OR_ZERO(this_port);2196}2197 2198/**2199 * parport_ip32_exit - module termination function2200 */2201static void __exit parport_ip32_exit(void)2202{2203	parport_ip32_unregister_port(this_port);2204}2205 2206/*--- Module stuff -----------------------------------------------------*/2207 2208MODULE_AUTHOR("Arnaud Giersch <arnaud.giersch@free.fr>");2209MODULE_DESCRIPTION("SGI IP32 built-in parallel port driver");2210MODULE_LICENSE("GPL");2211MODULE_VERSION("0.6");		/* update in parport_ip32_init() too */2212 2213module_init(parport_ip32_init);2214module_exit(parport_ip32_exit);2215 2216module_param(verbose_probing, bool, S_IRUGO);2217MODULE_PARM_DESC(verbose_probing, "Log chit-chat during initialization");2218 2219module_param(features, uint, S_IRUGO);2220MODULE_PARM_DESC(features,2221		 "Bit mask of features to enable"2222		 ", bit 0: IRQ support"2223		 ", bit 1: DMA support"2224		 ", bit 2: hardware SPP mode"2225		 ", bit 3: hardware EPP mode"2226		 ", bit 4: hardware ECP mode");2227