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linux/drivers/parport/parport_ip32.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

2249 lines
67 KiB
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/* Low-level parallel port routines for built-in port on SGI IP32
*
* Author: Arnaud Giersch <arnaud.giersch@free.fr>
*
* Based on parport_pc.c by
* Phil Blundell, Tim Waugh, Jose Renau, David Campbell,
* Andrea Arcangeli, et al.
*
* Thanks to Ilya A. Volynets-Evenbakh for his help.
*
* Copyright (C) 2005, 2006 Arnaud Giersch.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* Current status:
*
* Basic SPP and PS2 modes are supported.
* Support for parallel port IRQ is present.
* Hardware SPP (a.k.a. compatibility), EPP, and ECP modes are
* supported.
* SPP/ECP FIFO can be driven in PIO or DMA mode. PIO mode can work with
* or without interrupt support.
*
* Hardware ECP mode is not fully implemented (ecp_read_data and
* ecp_write_addr are actually missing).
*
* To do:
*
* Fully implement ECP mode.
* EPP and ECP mode need to be tested. I currently do not own any
* peripheral supporting these extended mode, and cannot test them.
* If DMA mode works well, decide if support for PIO FIFO modes should be
* dropped.
* Use the io{read,write} family functions when they become available in
* the linux-mips.org tree. Note: the MIPS specific functions readsb()
* and writesb() are to be translated by ioread8_rep() and iowrite8_rep()
* respectively.
*/
/* The built-in parallel port on the SGI 02 workstation (a.k.a. IP32) is an
* IEEE 1284 parallel port driven by a Texas Instrument TL16PIR552PH chip[1].
* This chip supports SPP, bidirectional, EPP and ECP modes. It has a 16 byte
* FIFO buffer and supports DMA transfers.
*
* [1] http://focus.ti.com/docs/prod/folders/print/tl16pir552.html
*
* Theoretically, we could simply use the parport_pc module. It is however
* not so simple. The parport_pc code assumes that the parallel port
* registers are port-mapped. On the O2, they are memory-mapped.
* Furthermore, each register is replicated on 256 consecutive addresses (as
* it is for the built-in serial ports on the same chip).
*/
/*--- Some configuration defines ---------------------------------------*/
/* DEBUG_PARPORT_IP32
* 0 disable debug
* 1 standard level: pr_debug1 is enabled
* 2 parport_ip32_dump_state is enabled
* >=3 verbose level: pr_debug is enabled
*/
#if !defined(DEBUG_PARPORT_IP32)
# define DEBUG_PARPORT_IP32 0 /* 0 (disabled) for production */
#endif
/*----------------------------------------------------------------------*/
/* Setup DEBUG macros. This is done before any includes, just in case we
* activate pr_debug() with DEBUG_PARPORT_IP32 >= 3.
*/
#if DEBUG_PARPORT_IP32 == 1
# warning DEBUG_PARPORT_IP32 == 1
#elif DEBUG_PARPORT_IP32 == 2
# warning DEBUG_PARPORT_IP32 == 2
#elif DEBUG_PARPORT_IP32 >= 3
# warning DEBUG_PARPORT_IP32 >= 3
# if !defined(DEBUG)
# define DEBUG /* enable pr_debug() in kernel.h */
# endif
#endif
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/parport.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <asm/io.h>
#include <asm/ip32/ip32_ints.h>
#include <asm/ip32/mace.h>
/*--- Global variables -------------------------------------------------*/
/* Verbose probing on by default for debugging. */
#if DEBUG_PARPORT_IP32 >= 1
# define DEFAULT_VERBOSE_PROBING 1
#else
# define DEFAULT_VERBOSE_PROBING 0
#endif
/* Default prefix for printk */
#define PPIP32 "parport_ip32: "
/*
* These are the module parameters:
* @features: bit mask of features to enable/disable
* (all enabled by default)
* @verbose_probing: log chit-chat during initialization
*/
#define PARPORT_IP32_ENABLE_IRQ (1U << 0)
#define PARPORT_IP32_ENABLE_DMA (1U << 1)
#define PARPORT_IP32_ENABLE_SPP (1U << 2)
#define PARPORT_IP32_ENABLE_EPP (1U << 3)
#define PARPORT_IP32_ENABLE_ECP (1U << 4)
static unsigned int features = ~0U;
static int verbose_probing = DEFAULT_VERBOSE_PROBING;
/* We do not support more than one port. */
static struct parport *this_port = NULL;
/* Timing constants for FIFO modes. */
#define FIFO_NFAULT_TIMEOUT 100 /* milliseconds */
#define FIFO_POLLING_INTERVAL 50 /* microseconds */
/*--- I/O register definitions -----------------------------------------*/
/**
* struct parport_ip32_regs - virtual addresses of parallel port registers
* @data: Data Register
* @dsr: Device Status Register
* @dcr: Device Control Register
* @eppAddr: EPP Address Register
* @eppData0: EPP Data Register 0
* @eppData1: EPP Data Register 1
* @eppData2: EPP Data Register 2
* @eppData3: EPP Data Register 3
* @ecpAFifo: ECP Address FIFO
* @fifo: General FIFO register. The same address is used for:
* - cFifo, the Parallel Port DATA FIFO
* - ecpDFifo, the ECP Data FIFO
* - tFifo, the ECP Test FIFO
* @cnfgA: Configuration Register A
* @cnfgB: Configuration Register B
* @ecr: Extended Control Register
*/
struct parport_ip32_regs {
void __iomem *data;
void __iomem *dsr;
void __iomem *dcr;
void __iomem *eppAddr;
void __iomem *eppData0;
void __iomem *eppData1;
void __iomem *eppData2;
void __iomem *eppData3;
void __iomem *ecpAFifo;
void __iomem *fifo;
void __iomem *cnfgA;
void __iomem *cnfgB;
void __iomem *ecr;
};
/* Device Status Register */
#define DSR_nBUSY (1U << 7) /* PARPORT_STATUS_BUSY */
#define DSR_nACK (1U << 6) /* PARPORT_STATUS_ACK */
#define DSR_PERROR (1U << 5) /* PARPORT_STATUS_PAPEROUT */
#define DSR_SELECT (1U << 4) /* PARPORT_STATUS_SELECT */
#define DSR_nFAULT (1U << 3) /* PARPORT_STATUS_ERROR */
#define DSR_nPRINT (1U << 2) /* specific to TL16PIR552 */
/* #define DSR_reserved (1U << 1) */
#define DSR_TIMEOUT (1U << 0) /* EPP timeout */
/* Device Control Register */
/* #define DCR_reserved (1U << 7) | (1U << 6) */
#define DCR_DIR (1U << 5) /* direction */
#define DCR_IRQ (1U << 4) /* interrupt on nAck */
#define DCR_SELECT (1U << 3) /* PARPORT_CONTROL_SELECT */
#define DCR_nINIT (1U << 2) /* PARPORT_CONTROL_INIT */
#define DCR_AUTOFD (1U << 1) /* PARPORT_CONTROL_AUTOFD */
#define DCR_STROBE (1U << 0) /* PARPORT_CONTROL_STROBE */
/* ECP Configuration Register A */
#define CNFGA_IRQ (1U << 7)
#define CNFGA_ID_MASK ((1U << 6) | (1U << 5) | (1U << 4))
#define CNFGA_ID_SHIFT 4
#define CNFGA_ID_16 (00U << CNFGA_ID_SHIFT)
#define CNFGA_ID_8 (01U << CNFGA_ID_SHIFT)
#define CNFGA_ID_32 (02U << CNFGA_ID_SHIFT)
/* #define CNFGA_reserved (1U << 3) */
#define CNFGA_nBYTEINTRANS (1U << 2)
#define CNFGA_PWORDLEFT ((1U << 1) | (1U << 0))
/* ECP Configuration Register B */
#define CNFGB_COMPRESS (1U << 7)
#define CNFGB_INTRVAL (1U << 6)
#define CNFGB_IRQ_MASK ((1U << 5) | (1U << 4) | (1U << 3))
#define CNFGB_IRQ_SHIFT 3
#define CNFGB_DMA_MASK ((1U << 2) | (1U << 1) | (1U << 0))
#define CNFGB_DMA_SHIFT 0
/* Extended Control Register */
#define ECR_MODE_MASK ((1U << 7) | (1U << 6) | (1U << 5))
#define ECR_MODE_SHIFT 5
#define ECR_MODE_SPP (00U << ECR_MODE_SHIFT)
#define ECR_MODE_PS2 (01U << ECR_MODE_SHIFT)
#define ECR_MODE_PPF (02U << ECR_MODE_SHIFT)
#define ECR_MODE_ECP (03U << ECR_MODE_SHIFT)
#define ECR_MODE_EPP (04U << ECR_MODE_SHIFT)
/* #define ECR_MODE_reserved (05U << ECR_MODE_SHIFT) */
#define ECR_MODE_TST (06U << ECR_MODE_SHIFT)
#define ECR_MODE_CFG (07U << ECR_MODE_SHIFT)
#define ECR_nERRINTR (1U << 4)
#define ECR_DMAEN (1U << 3)
#define ECR_SERVINTR (1U << 2)
#define ECR_F_FULL (1U << 1)
#define ECR_F_EMPTY (1U << 0)
/*--- Private data -----------------------------------------------------*/
/**
* enum parport_ip32_irq_mode - operation mode of interrupt handler
* @PARPORT_IP32_IRQ_FWD: forward interrupt to the upper parport layer
* @PARPORT_IP32_IRQ_HERE: interrupt is handled locally
*/
enum parport_ip32_irq_mode { PARPORT_IP32_IRQ_FWD, PARPORT_IP32_IRQ_HERE };
/**
* struct parport_ip32_private - private stuff for &struct parport
* @regs: register addresses
* @dcr_cache: cached contents of DCR
* @dcr_writable: bit mask of writable DCR bits
* @pword: number of bytes per PWord
* @fifo_depth: number of PWords that FIFO will hold
* @readIntrThreshold: minimum number of PWords we can read
* if we get an interrupt
* @writeIntrThreshold: minimum number of PWords we can write
* if we get an interrupt
* @irq_mode: operation mode of interrupt handler for this port
* @irq_complete: mutex used to wait for an interrupt to occur
*/
struct parport_ip32_private {
struct parport_ip32_regs regs;
unsigned int dcr_cache;
unsigned int dcr_writable;
unsigned int pword;
unsigned int fifo_depth;
unsigned int readIntrThreshold;
unsigned int writeIntrThreshold;
enum parport_ip32_irq_mode irq_mode;
struct completion irq_complete;
};
/*--- Debug code -------------------------------------------------------*/
/*
* pr_debug1 - print debug messages
*
* This is like pr_debug(), but is defined for %DEBUG_PARPORT_IP32 >= 1
*/
#if DEBUG_PARPORT_IP32 >= 1
# define pr_debug1(...) printk(KERN_DEBUG __VA_ARGS__)
#else /* DEBUG_PARPORT_IP32 < 1 */
# define pr_debug1(...) do { } while (0)
#endif
/*
* pr_trace, pr_trace1 - trace function calls
* @p: pointer to &struct parport
* @fmt: printk format string
* @...: parameters for format string
*
* Macros used to trace function calls. The given string is formatted after
* function name. pr_trace() uses pr_debug(), and pr_trace1() uses
* pr_debug1(). __pr_trace() is the low-level macro and is not to be used
* directly.
*/
#define __pr_trace(pr, p, fmt, ...) \
pr("%s: %s" fmt "\n", \
({ const struct parport *__p = (p); \
__p ? __p->name : "parport_ip32"; }), \
__func__ , ##__VA_ARGS__)
#define pr_trace(p, fmt, ...) __pr_trace(pr_debug, p, fmt , ##__VA_ARGS__)
#define pr_trace1(p, fmt, ...) __pr_trace(pr_debug1, p, fmt , ##__VA_ARGS__)
/*
* __pr_probe, pr_probe - print message if @verbose_probing is true
* @p: pointer to &struct parport
* @fmt: printk format string
* @...: parameters for format string
*
* For new lines, use pr_probe(). Use __pr_probe() for continued lines.
*/
#define __pr_probe(...) \
do { if (verbose_probing) printk(__VA_ARGS__); } while (0)
#define pr_probe(p, fmt, ...) \
__pr_probe(KERN_INFO PPIP32 "0x%lx: " fmt, (p)->base , ##__VA_ARGS__)
/*
* parport_ip32_dump_state - print register status of parport
* @p: pointer to &struct parport
* @str: string to add in message
* @show_ecp_config: shall we dump ECP configuration registers too?
*
* This function is only here for debugging purpose, and should be used with
* care. Reading the parallel port registers may have undesired side effects.
* Especially if @show_ecp_config is true, the parallel port is resetted.
* This function is only defined if %DEBUG_PARPORT_IP32 >= 2.
*/
#if DEBUG_PARPORT_IP32 >= 2
static void parport_ip32_dump_state(struct parport *p, char *str,
unsigned int show_ecp_config)
{
struct parport_ip32_private * const priv = p->physport->private_data;
unsigned int i;
printk(KERN_DEBUG PPIP32 "%s: state (%s):\n", p->name, str);
{
static const char ecr_modes[8][4] = {"SPP", "PS2", "PPF",
"ECP", "EPP", "???",
"TST", "CFG"};
unsigned int ecr = readb(priv->regs.ecr);
printk(KERN_DEBUG PPIP32 " ecr=0x%02x", ecr);
printk(" %s",
ecr_modes[(ecr & ECR_MODE_MASK) >> ECR_MODE_SHIFT]);
if (ecr & ECR_nERRINTR)
printk(",nErrIntrEn");
if (ecr & ECR_DMAEN)
printk(",dmaEn");
if (ecr & ECR_SERVINTR)
printk(",serviceIntr");
if (ecr & ECR_F_FULL)
printk(",f_full");
if (ecr & ECR_F_EMPTY)
printk(",f_empty");
printk("\n");
}
if (show_ecp_config) {
unsigned int oecr, cnfgA, cnfgB;
oecr = readb(priv->regs.ecr);
writeb(ECR_MODE_PS2, priv->regs.ecr);
writeb(ECR_MODE_CFG, priv->regs.ecr);
cnfgA = readb(priv->regs.cnfgA);
cnfgB = readb(priv->regs.cnfgB);
writeb(ECR_MODE_PS2, priv->regs.ecr);
writeb(oecr, priv->regs.ecr);
printk(KERN_DEBUG PPIP32 " cnfgA=0x%02x", cnfgA);
printk(" ISA-%s", (cnfgA & CNFGA_IRQ) ? "Level" : "Pulses");
switch (cnfgA & CNFGA_ID_MASK) {
case CNFGA_ID_8:
printk(",8 bits");
break;
case CNFGA_ID_16:
printk(",16 bits");
break;
case CNFGA_ID_32:
printk(",32 bits");
break;
default:
printk(",unknown ID");
break;
}
if (!(cnfgA & CNFGA_nBYTEINTRANS))
printk(",ByteInTrans");
if ((cnfgA & CNFGA_ID_MASK) != CNFGA_ID_8)
printk(",%d byte%s left", cnfgA & CNFGA_PWORDLEFT,
((cnfgA & CNFGA_PWORDLEFT) > 1) ? "s" : "");
printk("\n");
printk(KERN_DEBUG PPIP32 " cnfgB=0x%02x", cnfgB);
printk(" irq=%u,dma=%u",
(cnfgB & CNFGB_IRQ_MASK) >> CNFGB_IRQ_SHIFT,
(cnfgB & CNFGB_DMA_MASK) >> CNFGB_DMA_SHIFT);
printk(",intrValue=%d", !!(cnfgB & CNFGB_INTRVAL));
if (cnfgB & CNFGB_COMPRESS)
printk(",compress");
printk("\n");
}
for (i = 0; i < 2; i++) {
unsigned int dcr = i ? priv->dcr_cache : readb(priv->regs.dcr);
printk(KERN_DEBUG PPIP32 " dcr(%s)=0x%02x",
i ? "soft" : "hard", dcr);
printk(" %s", (dcr & DCR_DIR) ? "rev" : "fwd");
if (dcr & DCR_IRQ)
printk(",ackIntEn");
if (!(dcr & DCR_SELECT))
printk(",nSelectIn");
if (dcr & DCR_nINIT)
printk(",nInit");
if (!(dcr & DCR_AUTOFD))
printk(",nAutoFD");
if (!(dcr & DCR_STROBE))
printk(",nStrobe");
printk("\n");
}
#define sep (f++ ? ',' : ' ')
{
unsigned int f = 0;
unsigned int dsr = readb(priv->regs.dsr);
printk(KERN_DEBUG PPIP32 " dsr=0x%02x", dsr);
if (!(dsr & DSR_nBUSY))
printk("%cBusy", sep);
if (dsr & DSR_nACK)
printk("%cnAck", sep);
if (dsr & DSR_PERROR)
printk("%cPError", sep);
if (dsr & DSR_SELECT)
printk("%cSelect", sep);
if (dsr & DSR_nFAULT)
printk("%cnFault", sep);
if (!(dsr & DSR_nPRINT))
printk("%c(Print)", sep);
if (dsr & DSR_TIMEOUT)
printk("%cTimeout", sep);
printk("\n");
}
#undef sep
}
#else /* DEBUG_PARPORT_IP32 < 2 */
#define parport_ip32_dump_state(...) do { } while (0)
#endif
/*
* CHECK_EXTRA_BITS - track and log extra bits
* @p: pointer to &struct parport
* @b: byte to inspect
* @m: bit mask of authorized bits
*
* This is used to track and log extra bits that should not be there in
* parport_ip32_write_control() and parport_ip32_frob_control(). It is only
* defined if %DEBUG_PARPORT_IP32 >= 1.
*/
#if DEBUG_PARPORT_IP32 >= 1
#define CHECK_EXTRA_BITS(p, b, m) \
do { \
unsigned int __b = (b), __m = (m); \
if (__b & ~__m) \
pr_debug1(PPIP32 "%s: extra bits in %s(%s): " \
"0x%02x/0x%02x\n", \
(p)->name, __func__, #b, __b, __m); \
} while (0)
#else /* DEBUG_PARPORT_IP32 < 1 */
#define CHECK_EXTRA_BITS(...) do { } while (0)
#endif
/*--- IP32 parallel port DMA operations --------------------------------*/
/**
* struct parport_ip32_dma_data - private data needed for DMA operation
* @dir: DMA direction (from or to device)
* @buf: buffer physical address
* @len: buffer length
* @next: address of next bytes to DMA transfer
* @left: number of bytes remaining
* @ctx: next context to write (0: context_a; 1: context_b)
* @irq_on: are the DMA IRQs currently enabled?
* @lock: spinlock to protect access to the structure
*/
struct parport_ip32_dma_data {
enum dma_data_direction dir;
dma_addr_t buf;
dma_addr_t next;
size_t len;
size_t left;
unsigned int ctx;
unsigned int irq_on;
spinlock_t lock;
};
static struct parport_ip32_dma_data parport_ip32_dma;
/**
* parport_ip32_dma_setup_context - setup next DMA context
* @limit: maximum data size for the context
*
* The alignment constraints must be verified in caller function, and the
* parameter @limit must be set accordingly.
*/
static void parport_ip32_dma_setup_context(unsigned int limit)
{
unsigned long flags;
spin_lock_irqsave(&parport_ip32_dma.lock, flags);
if (parport_ip32_dma.left > 0) {
/* Note: ctxreg is "volatile" here only because
* mace->perif.ctrl.parport.context_a and context_b are
* "volatile". */
volatile u64 __iomem *ctxreg = (parport_ip32_dma.ctx == 0) ?
&mace->perif.ctrl.parport.context_a :
&mace->perif.ctrl.parport.context_b;
u64 count;
u64 ctxval;
if (parport_ip32_dma.left <= limit) {
count = parport_ip32_dma.left;
ctxval = MACEPAR_CONTEXT_LASTFLAG;
} else {
count = limit;
ctxval = 0;
}
pr_trace(NULL,
"(%u): 0x%04x:0x%04x, %u -> %u%s",
limit,
(unsigned int)parport_ip32_dma.buf,
(unsigned int)parport_ip32_dma.next,
(unsigned int)count,
parport_ip32_dma.ctx, ctxval ? "*" : "");
ctxval |= parport_ip32_dma.next &
MACEPAR_CONTEXT_BASEADDR_MASK;
ctxval |= ((count - 1) << MACEPAR_CONTEXT_DATALEN_SHIFT) &
MACEPAR_CONTEXT_DATALEN_MASK;
writeq(ctxval, ctxreg);
parport_ip32_dma.next += count;
parport_ip32_dma.left -= count;
parport_ip32_dma.ctx ^= 1U;
}
/* If there is nothing more to send, disable IRQs to avoid to
* face an IRQ storm which can lock the machine. Disable them
* only once. */
if (parport_ip32_dma.left == 0 && parport_ip32_dma.irq_on) {
pr_debug(PPIP32 "IRQ off (ctx)\n");
disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
parport_ip32_dma.irq_on = 0;
}
spin_unlock_irqrestore(&parport_ip32_dma.lock, flags);
}
/**
* parport_ip32_dma_interrupt - DMA interrupt handler
* @irq: interrupt number
* @dev_id: unused
*/
static irqreturn_t parport_ip32_dma_interrupt(int irq, void *dev_id)
{
if (parport_ip32_dma.left)
pr_trace(NULL, "(%d): ctx=%d", irq, parport_ip32_dma.ctx);
parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
return IRQ_HANDLED;
}
#if DEBUG_PARPORT_IP32
static irqreturn_t parport_ip32_merr_interrupt(int irq, void *dev_id)
{
pr_trace1(NULL, "(%d)", irq);
return IRQ_HANDLED;
}
#endif
/**
* parport_ip32_dma_start - begins a DMA transfer
* @dir: DMA direction: DMA_TO_DEVICE or DMA_FROM_DEVICE
* @addr: pointer to data buffer
* @count: buffer size
*
* Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
* correctly balanced.
*/
static int parport_ip32_dma_start(enum dma_data_direction dir,
void *addr, size_t count)
{
unsigned int limit;
u64 ctrl;
pr_trace(NULL, "(%d, %lu)", dir, (unsigned long)count);
/* FIXME - add support for DMA_FROM_DEVICE. In this case, buffer must
* be 64 bytes aligned. */
BUG_ON(dir != DMA_TO_DEVICE);
/* Reset DMA controller */
ctrl = MACEPAR_CTLSTAT_RESET;
writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
/* DMA IRQs should normally be enabled */
if (!parport_ip32_dma.irq_on) {
WARN_ON(1);
enable_irq(MACEISA_PAR_CTXA_IRQ);
enable_irq(MACEISA_PAR_CTXB_IRQ);
parport_ip32_dma.irq_on = 1;
}
/* Prepare DMA pointers */
parport_ip32_dma.dir = dir;
parport_ip32_dma.buf = dma_map_single(NULL, addr, count, dir);
parport_ip32_dma.len = count;
parport_ip32_dma.next = parport_ip32_dma.buf;
parport_ip32_dma.left = parport_ip32_dma.len;
parport_ip32_dma.ctx = 0;
/* Setup DMA direction and first two contexts */
ctrl = (dir == DMA_TO_DEVICE) ? 0 : MACEPAR_CTLSTAT_DIRECTION;
writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
/* Single transfer should not cross a 4K page boundary */
limit = MACEPAR_CONTEXT_DATA_BOUND -
(parport_ip32_dma.next & (MACEPAR_CONTEXT_DATA_BOUND - 1));
parport_ip32_dma_setup_context(limit);
parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
/* Real start of DMA transfer */
ctrl |= MACEPAR_CTLSTAT_ENABLE;
writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
return 0;
}
/**
* parport_ip32_dma_stop - ends a running DMA transfer
*
* Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
* correctly balanced.
*/
static void parport_ip32_dma_stop(void)
{
u64 ctx_a;
u64 ctx_b;
u64 ctrl;
u64 diag;
size_t res[2]; /* {[0] = res_a, [1] = res_b} */
pr_trace(NULL, "()");
/* Disable IRQs */
spin_lock_irq(&parport_ip32_dma.lock);
if (parport_ip32_dma.irq_on) {
pr_debug(PPIP32 "IRQ off (stop)\n");
disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
parport_ip32_dma.irq_on = 0;
}
spin_unlock_irq(&parport_ip32_dma.lock);
/* Force IRQ synchronization, even if the IRQs were disabled
* elsewhere. */
synchronize_irq(MACEISA_PAR_CTXA_IRQ);
synchronize_irq(MACEISA_PAR_CTXB_IRQ);
/* Stop DMA transfer */
ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
ctrl &= ~MACEPAR_CTLSTAT_ENABLE;
writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
/* Adjust residue (parport_ip32_dma.left) */
ctx_a = readq(&mace->perif.ctrl.parport.context_a);
ctx_b = readq(&mace->perif.ctrl.parport.context_b);
ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
diag = readq(&mace->perif.ctrl.parport.diagnostic);
res[0] = (ctrl & MACEPAR_CTLSTAT_CTXA_VALID) ?
1 + ((ctx_a & MACEPAR_CONTEXT_DATALEN_MASK) >>
MACEPAR_CONTEXT_DATALEN_SHIFT) :
0;
res[1] = (ctrl & MACEPAR_CTLSTAT_CTXB_VALID) ?
1 + ((ctx_b & MACEPAR_CONTEXT_DATALEN_MASK) >>
MACEPAR_CONTEXT_DATALEN_SHIFT) :
0;
if (diag & MACEPAR_DIAG_DMACTIVE)
res[(diag & MACEPAR_DIAG_CTXINUSE) != 0] =
1 + ((diag & MACEPAR_DIAG_CTRMASK) >>
MACEPAR_DIAG_CTRSHIFT);
parport_ip32_dma.left += res[0] + res[1];
/* Reset DMA controller, and re-enable IRQs */
ctrl = MACEPAR_CTLSTAT_RESET;
writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
pr_debug(PPIP32 "IRQ on (stop)\n");
enable_irq(MACEISA_PAR_CTXA_IRQ);
enable_irq(MACEISA_PAR_CTXB_IRQ);
parport_ip32_dma.irq_on = 1;
dma_unmap_single(NULL, parport_ip32_dma.buf, parport_ip32_dma.len,
parport_ip32_dma.dir);
}
/**
* parport_ip32_dma_get_residue - get residue from last DMA transfer
*
* Returns the number of bytes remaining from last DMA transfer.
*/
static inline size_t parport_ip32_dma_get_residue(void)
{
return parport_ip32_dma.left;
}
/**
* parport_ip32_dma_register - initialize DMA engine
*
* Returns zero for success.
*/
static int parport_ip32_dma_register(void)
{
int err;
spin_lock_init(&parport_ip32_dma.lock);
parport_ip32_dma.irq_on = 1;
/* Reset DMA controller */
writeq(MACEPAR_CTLSTAT_RESET, &mace->perif.ctrl.parport.cntlstat);
/* Request IRQs */
err = request_irq(MACEISA_PAR_CTXA_IRQ, parport_ip32_dma_interrupt,
0, "parport_ip32", NULL);
if (err)
goto fail_a;
err = request_irq(MACEISA_PAR_CTXB_IRQ, parport_ip32_dma_interrupt,
0, "parport_ip32", NULL);
if (err)
goto fail_b;
#if DEBUG_PARPORT_IP32
/* FIXME - what is this IRQ for? */
err = request_irq(MACEISA_PAR_MERR_IRQ, parport_ip32_merr_interrupt,
0, "parport_ip32", NULL);
if (err)
goto fail_merr;
#endif
return 0;
#if DEBUG_PARPORT_IP32
fail_merr:
free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
#endif
fail_b:
free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
fail_a:
return err;
}
/**
* parport_ip32_dma_unregister - release and free resources for DMA engine
*/
static void parport_ip32_dma_unregister(void)
{
#if DEBUG_PARPORT_IP32
free_irq(MACEISA_PAR_MERR_IRQ, NULL);
#endif
free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
}
/*--- Interrupt handlers and associates --------------------------------*/
/**
* parport_ip32_wakeup - wakes up code waiting for an interrupt
* @p: pointer to &struct parport
*/
static inline void parport_ip32_wakeup(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
complete(&priv->irq_complete);
}
/**
* parport_ip32_interrupt - interrupt handler
* @irq: interrupt number
* @dev_id: pointer to &struct parport
*
* Caught interrupts are forwarded to the upper parport layer if IRQ_mode is
* %PARPORT_IP32_IRQ_FWD.
*/
static irqreturn_t parport_ip32_interrupt(int irq, void *dev_id)
{
struct parport * const p = dev_id;
struct parport_ip32_private * const priv = p->physport->private_data;
enum parport_ip32_irq_mode irq_mode = priv->irq_mode;
switch (irq_mode) {
case PARPORT_IP32_IRQ_FWD:
parport_generic_irq(irq, p, regs);
break;
case PARPORT_IP32_IRQ_HERE:
parport_ip32_wakeup(p);
break;
}
return IRQ_HANDLED;
}
/*--- Some utility function to manipulate ECR register -----------------*/
/**
* parport_ip32_read_econtrol - read contents of the ECR register
* @p: pointer to &struct parport
*/
static inline unsigned int parport_ip32_read_econtrol(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return readb(priv->regs.ecr);
}
/**
* parport_ip32_write_econtrol - write new contents to the ECR register
* @p: pointer to &struct parport
* @c: new value to write
*/
static inline void parport_ip32_write_econtrol(struct parport *p,
unsigned int c)
{
struct parport_ip32_private * const priv = p->physport->private_data;
writeb(c, priv->regs.ecr);
}
/**
* parport_ip32_frob_econtrol - change bits from the ECR register
* @p: pointer to &struct parport
* @mask: bit mask of bits to change
* @val: new value for changed bits
*
* Read from the ECR, mask out the bits in @mask, exclusive-or with the bits
* in @val, and write the result to the ECR.
*/
static inline void parport_ip32_frob_econtrol(struct parport *p,
unsigned int mask,
unsigned int val)
{
unsigned int c;
c = (parport_ip32_read_econtrol(p) & ~mask) ^ val;
parport_ip32_write_econtrol(p, c);
}
/**
* parport_ip32_set_mode - change mode of ECP port
* @p: pointer to &struct parport
* @mode: new mode to write in ECR
*
* ECR is reset in a sane state (interrupts and DMA disabled), and placed in
* mode @mode. Go through PS2 mode if needed.
*/
static void parport_ip32_set_mode(struct parport *p, unsigned int mode)
{
unsigned int omode;
mode &= ECR_MODE_MASK;
omode = parport_ip32_read_econtrol(p) & ECR_MODE_MASK;
if (!(mode == ECR_MODE_SPP || mode == ECR_MODE_PS2
|| omode == ECR_MODE_SPP || omode == ECR_MODE_PS2)) {
/* We have to go through PS2 mode */
unsigned int ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
parport_ip32_write_econtrol(p, ecr);
}
parport_ip32_write_econtrol(p, mode | ECR_nERRINTR | ECR_SERVINTR);
}
/*--- Basic functions needed for parport -------------------------------*/
/**
* parport_ip32_read_data - return current contents of the DATA register
* @p: pointer to &struct parport
*/
static inline unsigned char parport_ip32_read_data(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return readb(priv->regs.data);
}
/**
* parport_ip32_write_data - set new contents for the DATA register
* @p: pointer to &struct parport
* @d: new value to write
*/
static inline void parport_ip32_write_data(struct parport *p, unsigned char d)
{
struct parport_ip32_private * const priv = p->physport->private_data;
writeb(d, priv->regs.data);
}
/**
* parport_ip32_read_status - return current contents of the DSR register
* @p: pointer to &struct parport
*/
static inline unsigned char parport_ip32_read_status(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return readb(priv->regs.dsr);
}
/**
* __parport_ip32_read_control - return cached contents of the DCR register
* @p: pointer to &struct parport
*/
static inline unsigned int __parport_ip32_read_control(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return priv->dcr_cache; /* use soft copy */
}
/**
* __parport_ip32_write_control - set new contents for the DCR register
* @p: pointer to &struct parport
* @c: new value to write
*/
static inline void __parport_ip32_write_control(struct parport *p,
unsigned int c)
{
struct parport_ip32_private * const priv = p->physport->private_data;
CHECK_EXTRA_BITS(p, c, priv->dcr_writable);
c &= priv->dcr_writable; /* only writable bits */
writeb(c, priv->regs.dcr);
priv->dcr_cache = c; /* update soft copy */
}
/**
* __parport_ip32_frob_control - change bits from the DCR register
* @p: pointer to &struct parport
* @mask: bit mask of bits to change
* @val: new value for changed bits
*
* This is equivalent to read from the DCR, mask out the bits in @mask,
* exclusive-or with the bits in @val, and write the result to the DCR.
* Actually, the cached contents of the DCR is used.
*/
static inline void __parport_ip32_frob_control(struct parport *p,
unsigned int mask,
unsigned int val)
{
unsigned int c;
c = (__parport_ip32_read_control(p) & ~mask) ^ val;
__parport_ip32_write_control(p, c);
}
/**
* parport_ip32_read_control - return cached contents of the DCR register
* @p: pointer to &struct parport
*
* The return value is masked so as to only return the value of %DCR_STROBE,
* %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
*/
static inline unsigned char parport_ip32_read_control(struct parport *p)
{
const unsigned int rm =
DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
return __parport_ip32_read_control(p) & rm;
}
/**
* parport_ip32_write_control - set new contents for the DCR register
* @p: pointer to &struct parport
* @c: new value to write
*
* The value is masked so as to only change the value of %DCR_STROBE,
* %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
*/
static inline void parport_ip32_write_control(struct parport *p,
unsigned char c)
{
const unsigned int wm =
DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
CHECK_EXTRA_BITS(p, c, wm);
__parport_ip32_frob_control(p, wm, c & wm);
}
/**
* parport_ip32_frob_control - change bits from the DCR register
* @p: pointer to &struct parport
* @mask: bit mask of bits to change
* @val: new value for changed bits
*
* This differs from __parport_ip32_frob_control() in that it only allows to
* change the value of %DCR_STROBE, %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
*/
static inline unsigned char parport_ip32_frob_control(struct parport *p,
unsigned char mask,
unsigned char val)
{
const unsigned int wm =
DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
CHECK_EXTRA_BITS(p, mask, wm);
CHECK_EXTRA_BITS(p, val, wm);
__parport_ip32_frob_control(p, mask & wm, val & wm);
return parport_ip32_read_control(p);
}
/**
* parport_ip32_disable_irq - disable interrupts on the rising edge of nACK
* @p: pointer to &struct parport
*/
static inline void parport_ip32_disable_irq(struct parport *p)
{
__parport_ip32_frob_control(p, DCR_IRQ, 0);
}
/**
* parport_ip32_enable_irq - enable interrupts on the rising edge of nACK
* @p: pointer to &struct parport
*/
static inline void parport_ip32_enable_irq(struct parport *p)
{
__parport_ip32_frob_control(p, DCR_IRQ, DCR_IRQ);
}
/**
* parport_ip32_data_forward - enable host-to-peripheral communications
* @p: pointer to &struct parport
*
* Enable the data line drivers, for 8-bit host-to-peripheral communications.
*/
static inline void parport_ip32_data_forward(struct parport *p)
{
__parport_ip32_frob_control(p, DCR_DIR, 0);
}
/**
* parport_ip32_data_reverse - enable peripheral-to-host communications
* @p: pointer to &struct parport
*
* Place the data bus in a high impedance state, if @p->modes has the
* PARPORT_MODE_TRISTATE bit set.
*/
static inline void parport_ip32_data_reverse(struct parport *p)
{
__parport_ip32_frob_control(p, DCR_DIR, DCR_DIR);
}
/**
* parport_ip32_init_state - for core parport code
* @dev: pointer to &struct pardevice
* @s: pointer to &struct parport_state to initialize
*/
static void parport_ip32_init_state(struct pardevice *dev,
struct parport_state *s)
{
s->u.ip32.dcr = DCR_SELECT | DCR_nINIT;
s->u.ip32.ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
}
/**
* parport_ip32_save_state - for core parport code
* @p: pointer to &struct parport
* @s: pointer to &struct parport_state to save state to
*/
static void parport_ip32_save_state(struct parport *p,
struct parport_state *s)
{
s->u.ip32.dcr = __parport_ip32_read_control(p);
s->u.ip32.ecr = parport_ip32_read_econtrol(p);
}
/**
* parport_ip32_restore_state - for core parport code
* @p: pointer to &struct parport
* @s: pointer to &struct parport_state to restore state from
*/
static void parport_ip32_restore_state(struct parport *p,
struct parport_state *s)
{
parport_ip32_set_mode(p, s->u.ip32.ecr & ECR_MODE_MASK);
parport_ip32_write_econtrol(p, s->u.ip32.ecr);
__parport_ip32_write_control(p, s->u.ip32.dcr);
}
/*--- EPP mode functions -----------------------------------------------*/
/**
* parport_ip32_clear_epp_timeout - clear Timeout bit in EPP mode
* @p: pointer to &struct parport
*
* Returns 1 if the Timeout bit is clear, and 0 otherwise.
*/
static unsigned int parport_ip32_clear_epp_timeout(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
unsigned int cleared;
if (!(parport_ip32_read_status(p) & DSR_TIMEOUT))
cleared = 1;
else {
unsigned int r;
/* To clear timeout some chips require double read */
parport_ip32_read_status(p);
r = parport_ip32_read_status(p);
/* Some reset by writing 1 */
writeb(r | DSR_TIMEOUT, priv->regs.dsr);
/* Others by writing 0 */
writeb(r & ~DSR_TIMEOUT, priv->regs.dsr);
r = parport_ip32_read_status(p);
cleared = !(r & DSR_TIMEOUT);
}
pr_trace(p, "(): %s", cleared ? "cleared" : "failed");
return cleared;
}
/**
* parport_ip32_epp_read - generic EPP read function
* @eppreg: I/O register to read from
* @p: pointer to &struct parport
* @buf: buffer to store read data
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_read(void __iomem *eppreg,
struct parport *p, void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
size_t got;
parport_ip32_set_mode(p, ECR_MODE_EPP);
parport_ip32_data_reverse(p);
parport_ip32_write_control(p, DCR_nINIT);
if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
readsb(eppreg, buf, len);
if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
parport_ip32_clear_epp_timeout(p);
return -EIO;
}
got = len;
} else {
u8 *bufp = buf;
for (got = 0; got < len; got++) {
*bufp++ = readb(eppreg);
if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
parport_ip32_clear_epp_timeout(p);
break;
}
}
}
parport_ip32_data_forward(p);
parport_ip32_set_mode(p, ECR_MODE_PS2);
return got;
}
/**
* parport_ip32_epp_write - generic EPP write function
* @eppreg: I/O register to write to
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_write(void __iomem *eppreg,
struct parport *p, const void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
size_t written;
parport_ip32_set_mode(p, ECR_MODE_EPP);
parport_ip32_data_forward(p);
parport_ip32_write_control(p, DCR_nINIT);
if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
writesb(eppreg, buf, len);
if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
parport_ip32_clear_epp_timeout(p);
return -EIO;
}
written = len;
} else {
const u8 *bufp = buf;
for (written = 0; written < len; written++) {
writeb(*bufp++, eppreg);
if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
parport_ip32_clear_epp_timeout(p);
break;
}
}
}
parport_ip32_set_mode(p, ECR_MODE_PS2);
return written;
}
/**
* parport_ip32_epp_read_data - read a block of data in EPP mode
* @p: pointer to &struct parport
* @buf: buffer to store read data
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_read_data(struct parport *p, void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return parport_ip32_epp_read(priv->regs.eppData0, p, buf, len, flags);
}
/**
* parport_ip32_epp_write_data - write a block of data in EPP mode
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_write_data(struct parport *p, const void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return parport_ip32_epp_write(priv->regs.eppData0, p, buf, len, flags);
}
/**
* parport_ip32_epp_read_addr - read a block of addresses in EPP mode
* @p: pointer to &struct parport
* @buf: buffer to store read data
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_read_addr(struct parport *p, void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return parport_ip32_epp_read(priv->regs.eppAddr, p, buf, len, flags);
}
/**
* parport_ip32_epp_write_addr - write a block of addresses in EPP mode
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
* @flags: may be PARPORT_EPP_FAST
*/
static size_t parport_ip32_epp_write_addr(struct parport *p, const void *buf,
size_t len, int flags)
{
struct parport_ip32_private * const priv = p->physport->private_data;
return parport_ip32_epp_write(priv->regs.eppAddr, p, buf, len, flags);
}
/*--- ECP mode functions (FIFO) ----------------------------------------*/
/**
* parport_ip32_fifo_wait_break - check if the waiting function should return
* @p: pointer to &struct parport
* @expire: timeout expiring date, in jiffies
*
* parport_ip32_fifo_wait_break() checks if the waiting function should return
* immediately or not. The break conditions are:
* - expired timeout;
* - a pending signal;
* - nFault asserted low.
* This function also calls cond_resched().
*/
static unsigned int parport_ip32_fifo_wait_break(struct parport *p,
unsigned long expire)
{
cond_resched();
if (time_after(jiffies, expire)) {
pr_debug1(PPIP32 "%s: FIFO write timed out\n", p->name);
return 1;
}
if (signal_pending(current)) {
pr_debug1(PPIP32 "%s: Signal pending\n", p->name);
return 1;
}
if (!(parport_ip32_read_status(p) & DSR_nFAULT)) {
pr_debug1(PPIP32 "%s: nFault asserted low\n", p->name);
return 1;
}
return 0;
}
/**
* parport_ip32_fwp_wait_polling - wait for FIFO to empty (polling)
* @p: pointer to &struct parport
*
* Returns the number of bytes that can safely be written in the FIFO. A
* return value of zero means that the calling function should terminate as
* fast as possible.
*/
static unsigned int parport_ip32_fwp_wait_polling(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport * const physport = p->physport;
unsigned long expire;
unsigned int count;
unsigned int ecr;
expire = jiffies + physport->cad->timeout;
count = 0;
while (1) {
if (parport_ip32_fifo_wait_break(p, expire))
break;
/* Check FIFO state. We do nothing when the FIFO is nor full,
* nor empty. It appears that the FIFO full bit is not always
* reliable, the FIFO state is sometimes wrongly reported, and
* the chip gets confused if we give it another byte. */
ecr = parport_ip32_read_econtrol(p);
if (ecr & ECR_F_EMPTY) {
/* FIFO is empty, fill it up */
count = priv->fifo_depth;
break;
}
/* Wait a moment... */
udelay(FIFO_POLLING_INTERVAL);
} /* while (1) */
return count;
}
/**
* parport_ip32_fwp_wait_interrupt - wait for FIFO to empty (interrupt-driven)
* @p: pointer to &struct parport
*
* Returns the number of bytes that can safely be written in the FIFO. A
* return value of zero means that the calling function should terminate as
* fast as possible.
*/
static unsigned int parport_ip32_fwp_wait_interrupt(struct parport *p)
{
static unsigned int lost_interrupt = 0;
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport * const physport = p->physport;
unsigned long nfault_timeout;
unsigned long expire;
unsigned int count;
unsigned int ecr;
nfault_timeout = min((unsigned long)physport->cad->timeout,
msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
expire = jiffies + physport->cad->timeout;
count = 0;
while (1) {
if (parport_ip32_fifo_wait_break(p, expire))
break;
/* Initialize mutex used to take interrupts into account */
INIT_COMPLETION(priv->irq_complete);
/* Enable serviceIntr */
parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
/* Enabling serviceIntr while the FIFO is empty does not
* always generate an interrupt, so check for emptiness
* now. */
ecr = parport_ip32_read_econtrol(p);
if (!(ecr & ECR_F_EMPTY)) {
/* FIFO is not empty: wait for an interrupt or a
* timeout to occur */
wait_for_completion_interruptible_timeout(
&priv->irq_complete, nfault_timeout);
ecr = parport_ip32_read_econtrol(p);
if ((ecr & ECR_F_EMPTY) && !(ecr & ECR_SERVINTR)
&& !lost_interrupt) {
printk(KERN_WARNING PPIP32
"%s: lost interrupt in %s\n",
p->name, __func__);
lost_interrupt = 1;
}
}
/* Disable serviceIntr */
parport_ip32_frob_econtrol(p, ECR_SERVINTR, ECR_SERVINTR);
/* Check FIFO state */
if (ecr & ECR_F_EMPTY) {
/* FIFO is empty, fill it up */
count = priv->fifo_depth;
break;
} else if (ecr & ECR_SERVINTR) {
/* FIFO is not empty, but we know that can safely push
* writeIntrThreshold bytes into it */
count = priv->writeIntrThreshold;
break;
}
/* FIFO is not empty, and we did not get any interrupt.
* Either it's time to check for nFault, or a signal is
* pending. This is verified in
* parport_ip32_fifo_wait_break(), so we continue the loop. */
} /* while (1) */
return count;
}
/**
* parport_ip32_fifo_write_block_pio - write a block of data (PIO mode)
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
*
* Uses PIO to write the contents of the buffer @buf into the parallel port
* FIFO. Returns the number of bytes that were actually written. It can work
* with or without the help of interrupts. The parallel port must be
* correctly initialized before calling parport_ip32_fifo_write_block_pio().
*/
static size_t parport_ip32_fifo_write_block_pio(struct parport *p,
const void *buf, size_t len)
{
struct parport_ip32_private * const priv = p->physport->private_data;
const u8 *bufp = buf;
size_t left = len;
priv->irq_mode = PARPORT_IP32_IRQ_HERE;
while (left > 0) {
unsigned int count;
count = (p->irq == PARPORT_IRQ_NONE) ?
parport_ip32_fwp_wait_polling(p) :
parport_ip32_fwp_wait_interrupt(p);
if (count == 0)
break; /* Transmission should be stopped */
if (count > left)
count = left;
if (count == 1) {
writeb(*bufp, priv->regs.fifo);
bufp++, left--;
} else {
writesb(priv->regs.fifo, bufp, count);
bufp += count, left -= count;
}
}
priv->irq_mode = PARPORT_IP32_IRQ_FWD;
return len - left;
}
/**
* parport_ip32_fifo_write_block_dma - write a block of data (DMA mode)
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
*
* Uses DMA to write the contents of the buffer @buf into the parallel port
* FIFO. Returns the number of bytes that were actually written. The
* parallel port must be correctly initialized before calling
* parport_ip32_fifo_write_block_dma().
*/
static size_t parport_ip32_fifo_write_block_dma(struct parport *p,
const void *buf, size_t len)
{
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport * const physport = p->physport;
unsigned long nfault_timeout;
unsigned long expire;
size_t written;
unsigned int ecr;
priv->irq_mode = PARPORT_IP32_IRQ_HERE;
parport_ip32_dma_start(DMA_TO_DEVICE, (void *)buf, len);
INIT_COMPLETION(priv->irq_complete);
parport_ip32_frob_econtrol(p, ECR_DMAEN | ECR_SERVINTR, ECR_DMAEN);
nfault_timeout = min((unsigned long)physport->cad->timeout,
msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
expire = jiffies + physport->cad->timeout;
while (1) {
if (parport_ip32_fifo_wait_break(p, expire))
break;
wait_for_completion_interruptible_timeout(&priv->irq_complete,
nfault_timeout);
ecr = parport_ip32_read_econtrol(p);
if (ecr & ECR_SERVINTR)
break; /* DMA transfer just finished */
}
parport_ip32_dma_stop();
written = len - parport_ip32_dma_get_residue();
priv->irq_mode = PARPORT_IP32_IRQ_FWD;
return written;
}
/**
* parport_ip32_fifo_write_block - write a block of data
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
*
* Uses PIO or DMA to write the contents of the buffer @buf into the parallel
* p FIFO. Returns the number of bytes that were actually written.
*/
static size_t parport_ip32_fifo_write_block(struct parport *p,
const void *buf, size_t len)
{
size_t written = 0;
if (len)
/* FIXME - Maybe some threshold value should be set for @len
* under which we revert to PIO mode? */
written = (p->modes & PARPORT_MODE_DMA) ?
parport_ip32_fifo_write_block_dma(p, buf, len) :
parport_ip32_fifo_write_block_pio(p, buf, len);
return written;
}
/**
* parport_ip32_drain_fifo - wait for FIFO to empty
* @p: pointer to &struct parport
* @timeout: timeout, in jiffies
*
* This function waits for FIFO to empty. It returns 1 when FIFO is empty, or
* 0 if the timeout @timeout is reached before, or if a signal is pending.
*/
static unsigned int parport_ip32_drain_fifo(struct parport *p,
unsigned long timeout)
{
unsigned long expire = jiffies + timeout;
unsigned int polling_interval;
unsigned int counter;
/* Busy wait for approx. 200us */
for (counter = 0; counter < 40; counter++) {
if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
break;
if (time_after(jiffies, expire))
break;
if (signal_pending(current))
break;
udelay(5);
}
/* Poll slowly. Polling interval starts with 1 millisecond, and is
* increased exponentially until 128. */
polling_interval = 1; /* msecs */
while (!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY)) {
if (time_after_eq(jiffies, expire))
break;
msleep_interruptible(polling_interval);
if (signal_pending(current))
break;
if (polling_interval < 128)
polling_interval *= 2;
}
return !!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY);
}
/**
* parport_ip32_get_fifo_residue - reset FIFO
* @p: pointer to &struct parport
* @mode: current operation mode (ECR_MODE_PPF or ECR_MODE_ECP)
*
* This function resets FIFO, and returns the number of bytes remaining in it.
*/
static unsigned int parport_ip32_get_fifo_residue(struct parport *p,
unsigned int mode)
{
struct parport_ip32_private * const priv = p->physport->private_data;
unsigned int residue;
unsigned int cnfga;
/* FIXME - We are missing one byte if the printer is off-line. I
* don't know how to detect this. It looks that the full bit is not
* always reliable. For the moment, the problem is avoided in most
* cases by testing for BUSY in parport_ip32_compat_write_data().
*/
if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
residue = 0;
else {
pr_debug1(PPIP32 "%s: FIFO is stuck\n", p->name);
/* Stop all transfers.
*
* Microsoft's document instructs to drive DCR_STROBE to 0,
* but it doesn't work (at least in Compatibility mode, not
* tested in ECP mode). Switching directly to Test mode (as
* in parport_pc) is not an option: it does confuse the port,
* ECP service interrupts are no more working after that. A
* hard reset is then needed to revert to a sane state.
*
* Let's hope that the FIFO is really stuck and that the
* peripheral doesn't wake up now.
*/
parport_ip32_frob_control(p, DCR_STROBE, 0);
/* Fill up FIFO */
for (residue = priv->fifo_depth; residue > 0; residue--) {
if (parport_ip32_read_econtrol(p) & ECR_F_FULL)
break;
writeb(0x00, priv->regs.fifo);
}
}
if (residue)
pr_debug1(PPIP32 "%s: %d PWord%s left in FIFO\n",
p->name, residue,
(residue == 1) ? " was" : "s were");
/* Now reset the FIFO */
parport_ip32_set_mode(p, ECR_MODE_PS2);
/* Host recovery for ECP mode */
if (mode == ECR_MODE_ECP) {
parport_ip32_data_reverse(p);
parport_ip32_frob_control(p, DCR_nINIT, 0);
if (parport_wait_peripheral(p, DSR_PERROR, 0))
pr_debug1(PPIP32 "%s: PEerror timeout 1 in %s\n",
p->name, __func__);
parport_ip32_frob_control(p, DCR_STROBE, DCR_STROBE);
parport_ip32_frob_control(p, DCR_nINIT, DCR_nINIT);
if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR))
pr_debug1(PPIP32 "%s: PEerror timeout 2 in %s\n",
p->name, __func__);
}
/* Adjust residue if needed */
parport_ip32_set_mode(p, ECR_MODE_CFG);
cnfga = readb(priv->regs.cnfgA);
if (!(cnfga & CNFGA_nBYTEINTRANS)) {
pr_debug1(PPIP32 "%s: cnfgA contains 0x%02x\n",
p->name, cnfga);
pr_debug1(PPIP32 "%s: Accounting for extra byte\n",
p->name);
residue++;
}
/* Don't care about partial PWords since we do not support
* PWord != 1 byte. */
/* Back to forward PS2 mode. */
parport_ip32_set_mode(p, ECR_MODE_PS2);
parport_ip32_data_forward(p);
return residue;
}
/**
* parport_ip32_compat_write_data - write a block of data in SPP mode
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
* @flags: ignored
*/
static size_t parport_ip32_compat_write_data(struct parport *p,
const void *buf, size_t len,
int flags)
{
static unsigned int ready_before = 1;
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport * const physport = p->physport;
size_t written = 0;
/* Special case: a timeout of zero means we cannot call schedule().
* Also if O_NONBLOCK is set then use the default implementation. */
if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
return parport_ieee1284_write_compat(p, buf, len, flags);
/* Reset FIFO, go in forward mode, and disable ackIntEn */
parport_ip32_set_mode(p, ECR_MODE_PS2);
parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
parport_ip32_data_forward(p);
parport_ip32_disable_irq(p);
parport_ip32_set_mode(p, ECR_MODE_PPF);
physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
/* Wait for peripheral to become ready */
if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
DSR_nBUSY | DSR_nFAULT)) {
/* Avoid to flood the logs */
if (ready_before)
printk(KERN_INFO PPIP32 "%s: not ready in %s\n",
p->name, __func__);
ready_before = 0;
goto stop;
}
ready_before = 1;
written = parport_ip32_fifo_write_block(p, buf, len);
/* Wait FIFO to empty. Timeout is proportional to FIFO_depth. */
parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
/* Check for a potential residue */
written -= parport_ip32_get_fifo_residue(p, ECR_MODE_PPF);
/* Then, wait for BUSY to get low. */
if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
p->name, __func__);
stop:
/* Reset FIFO */
parport_ip32_set_mode(p, ECR_MODE_PS2);
physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
return written;
}
/*
* FIXME - Insert here parport_ip32_ecp_read_data().
*/
/**
* parport_ip32_ecp_write_data - write a block of data in ECP mode
* @p: pointer to &struct parport
* @buf: buffer of data to write
* @len: length of buffer @buf
* @flags: ignored
*/
static size_t parport_ip32_ecp_write_data(struct parport *p,
const void *buf, size_t len,
int flags)
{
static unsigned int ready_before = 1;
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport * const physport = p->physport;
size_t written = 0;
/* Special case: a timeout of zero means we cannot call schedule().
* Also if O_NONBLOCK is set then use the default implementation. */
if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
return parport_ieee1284_ecp_write_data(p, buf, len, flags);
/* Negotiate to forward mode if necessary. */
if (physport->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {
/* Event 47: Set nInit high. */
parport_ip32_frob_control(p, DCR_nINIT | DCR_AUTOFD,
DCR_nINIT | DCR_AUTOFD);
/* Event 49: PError goes high. */
if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR)) {
printk(KERN_DEBUG PPIP32 "%s: PError timeout in %s",
p->name, __func__);
physport->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
return 0;
}
}
/* Reset FIFO, go in forward mode, and disable ackIntEn */
parport_ip32_set_mode(p, ECR_MODE_PS2);
parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
parport_ip32_data_forward(p);
parport_ip32_disable_irq(p);
parport_ip32_set_mode(p, ECR_MODE_ECP);
physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
/* Wait for peripheral to become ready */
if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
DSR_nBUSY | DSR_nFAULT)) {
/* Avoid to flood the logs */
if (ready_before)
printk(KERN_INFO PPIP32 "%s: not ready in %s\n",
p->name, __func__);
ready_before = 0;
goto stop;
}
ready_before = 1;
written = parport_ip32_fifo_write_block(p, buf, len);
/* Wait FIFO to empty. Timeout is proportional to FIFO_depth. */
parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
/* Check for a potential residue */
written -= parport_ip32_get_fifo_residue(p, ECR_MODE_ECP);
/* Then, wait for BUSY to get low. */
if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
p->name, __func__);
stop:
/* Reset FIFO */
parport_ip32_set_mode(p, ECR_MODE_PS2);
physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
return written;
}
/*
* FIXME - Insert here parport_ip32_ecp_write_addr().
*/
/*--- Default parport operations ---------------------------------------*/
static __initdata struct parport_operations parport_ip32_ops = {
.write_data = parport_ip32_write_data,
.read_data = parport_ip32_read_data,
.write_control = parport_ip32_write_control,
.read_control = parport_ip32_read_control,
.frob_control = parport_ip32_frob_control,
.read_status = parport_ip32_read_status,
.enable_irq = parport_ip32_enable_irq,
.disable_irq = parport_ip32_disable_irq,
.data_forward = parport_ip32_data_forward,
.data_reverse = parport_ip32_data_reverse,
.init_state = parport_ip32_init_state,
.save_state = parport_ip32_save_state,
.restore_state = parport_ip32_restore_state,
.epp_write_data = parport_ieee1284_epp_write_data,
.epp_read_data = parport_ieee1284_epp_read_data,
.epp_write_addr = parport_ieee1284_epp_write_addr,
.epp_read_addr = parport_ieee1284_epp_read_addr,
.ecp_write_data = parport_ieee1284_ecp_write_data,
.ecp_read_data = parport_ieee1284_ecp_read_data,
.ecp_write_addr = parport_ieee1284_ecp_write_addr,
.compat_write_data = parport_ieee1284_write_compat,
.nibble_read_data = parport_ieee1284_read_nibble,
.byte_read_data = parport_ieee1284_read_byte,
.owner = THIS_MODULE,
};
/*--- Device detection -------------------------------------------------*/
/**
* parport_ip32_ecp_supported - check for an ECP port
* @p: pointer to the &parport structure
*
* Returns 1 if an ECP port is found, and 0 otherwise. This function actually
* checks if an Extended Control Register seems to be present. On successful
* return, the port is placed in SPP mode.
*/
static __init unsigned int parport_ip32_ecp_supported(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
unsigned int ecr;
ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
writeb(ecr, priv->regs.ecr);
if (readb(priv->regs.ecr) != (ecr | ECR_F_EMPTY))
goto fail;
pr_probe(p, "Found working ECR register\n");
parport_ip32_set_mode(p, ECR_MODE_SPP);
parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
return 1;
fail:
pr_probe(p, "ECR register not found\n");
return 0;
}
/**
* parport_ip32_fifo_supported - check for FIFO parameters
* @p: pointer to the &parport structure
*
* Check for FIFO parameters of an Extended Capabilities Port. Returns 1 on
* success, and 0 otherwise. Adjust FIFO parameters in the parport structure.
* On return, the port is placed in SPP mode.
*/
static __init unsigned int parport_ip32_fifo_supported(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
unsigned int configa, configb;
unsigned int pword;
unsigned int i;
/* Configuration mode */
parport_ip32_set_mode(p, ECR_MODE_CFG);
configa = readb(priv->regs.cnfgA);
configb = readb(priv->regs.cnfgB);
/* Find out PWord size */
switch (configa & CNFGA_ID_MASK) {
case CNFGA_ID_8:
pword = 1;
break;
case CNFGA_ID_16:
pword = 2;
break;
case CNFGA_ID_32:
pword = 4;
break;
default:
pr_probe(p, "Unknown implementation ID: 0x%0x\n",
(configa & CNFGA_ID_MASK) >> CNFGA_ID_SHIFT);
goto fail;
break;
}
if (pword != 1) {
pr_probe(p, "Unsupported PWord size: %u\n", pword);
goto fail;
}
priv->pword = pword;
pr_probe(p, "PWord is %u bits\n", 8 * priv->pword);
/* Check for compression support */
writeb(configb | CNFGB_COMPRESS, priv->regs.cnfgB);
if (readb(priv->regs.cnfgB) & CNFGB_COMPRESS)
pr_probe(p, "Hardware compression detected (unsupported)\n");
writeb(configb & ~CNFGB_COMPRESS, priv->regs.cnfgB);
/* Reset FIFO and go in test mode (no interrupt, no DMA) */
parport_ip32_set_mode(p, ECR_MODE_TST);
/* FIFO must be empty now */
if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
pr_probe(p, "FIFO not reset\n");
goto fail;
}
/* Find out FIFO depth. */
priv->fifo_depth = 0;
for (i = 0; i < 1024; i++) {
if (readb(priv->regs.ecr) & ECR_F_FULL) {
/* FIFO full */
priv->fifo_depth = i;
break;
}
writeb((u8)i, priv->regs.fifo);
}
if (i >= 1024) {
pr_probe(p, "Can't fill FIFO\n");
goto fail;
}
if (!priv->fifo_depth) {
pr_probe(p, "Can't get FIFO depth\n");
goto fail;
}
pr_probe(p, "FIFO is %u PWords deep\n", priv->fifo_depth);
/* Enable interrupts */
parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
/* Find out writeIntrThreshold: number of PWords we know we can write
* if we get an interrupt. */
priv->writeIntrThreshold = 0;
for (i = 0; i < priv->fifo_depth; i++) {
if (readb(priv->regs.fifo) != (u8)i) {
pr_probe(p, "Invalid data in FIFO\n");
goto fail;
}
if (!priv->writeIntrThreshold
&& readb(priv->regs.ecr) & ECR_SERVINTR)
/* writeIntrThreshold reached */
priv->writeIntrThreshold = i + 1;
if (i + 1 < priv->fifo_depth
&& readb(priv->regs.ecr) & ECR_F_EMPTY) {
/* FIFO empty before the last byte? */
pr_probe(p, "Data lost in FIFO\n");
goto fail;
}
}
if (!priv->writeIntrThreshold) {
pr_probe(p, "Can't get writeIntrThreshold\n");
goto fail;
}
pr_probe(p, "writeIntrThreshold is %u\n", priv->writeIntrThreshold);
/* FIFO must be empty now */
if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
pr_probe(p, "Can't empty FIFO\n");
goto fail;
}
/* Reset FIFO */
parport_ip32_set_mode(p, ECR_MODE_PS2);
/* Set reverse direction (must be in PS2 mode) */
parport_ip32_data_reverse(p);
/* Test FIFO, no interrupt, no DMA */
parport_ip32_set_mode(p, ECR_MODE_TST);
/* Enable interrupts */
parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
/* Find out readIntrThreshold: number of PWords we can read if we get
* an interrupt. */
priv->readIntrThreshold = 0;
for (i = 0; i < priv->fifo_depth; i++) {
writeb(0xaa, priv->regs.fifo);
if (readb(priv->regs.ecr) & ECR_SERVINTR) {
/* readIntrThreshold reached */
priv->readIntrThreshold = i + 1;
break;
}
}
if (!priv->readIntrThreshold) {
pr_probe(p, "Can't get readIntrThreshold\n");
goto fail;
}
pr_probe(p, "readIntrThreshold is %u\n", priv->readIntrThreshold);
/* Reset ECR */
parport_ip32_set_mode(p, ECR_MODE_PS2);
parport_ip32_data_forward(p);
parport_ip32_set_mode(p, ECR_MODE_SPP);
return 1;
fail:
priv->fifo_depth = 0;
parport_ip32_set_mode(p, ECR_MODE_SPP);
return 0;
}
/*--- Initialization code ----------------------------------------------*/
/**
* parport_ip32_make_isa_registers - compute (ISA) register addresses
* @regs: pointer to &struct parport_ip32_regs to fill
* @base: base address of standard and EPP registers
* @base_hi: base address of ECP registers
* @regshift: how much to shift register offset by
*
* Compute register addresses, according to the ISA standard. The addresses
* of the standard and EPP registers are computed from address @base. The
* addresses of the ECP registers are computed from address @base_hi.
*/
static void __init
parport_ip32_make_isa_registers(struct parport_ip32_regs *regs,
void __iomem *base, void __iomem *base_hi,
unsigned int regshift)
{
#define r_base(offset) ((u8 __iomem *)base + ((offset) << regshift))
#define r_base_hi(offset) ((u8 __iomem *)base_hi + ((offset) << regshift))
*regs = (struct parport_ip32_regs){
.data = r_base(0),
.dsr = r_base(1),
.dcr = r_base(2),
.eppAddr = r_base(3),
.eppData0 = r_base(4),
.eppData1 = r_base(5),
.eppData2 = r_base(6),
.eppData3 = r_base(7),
.ecpAFifo = r_base(0),
.fifo = r_base_hi(0),
.cnfgA = r_base_hi(0),
.cnfgB = r_base_hi(1),
.ecr = r_base_hi(2)
};
#undef r_base_hi
#undef r_base
}
/**
* parport_ip32_probe_port - probe and register IP32 built-in parallel port
*
* Returns the new allocated &parport structure. On error, an error code is
* encoded in return value with the ERR_PTR function.
*/
static __init struct parport *parport_ip32_probe_port(void)
{
struct parport_ip32_regs regs;
struct parport_ip32_private *priv = NULL;
struct parport_operations *ops = NULL;
struct parport *p = NULL;
int err;
parport_ip32_make_isa_registers(&regs, &mace->isa.parallel,
&mace->isa.ecp1284, 8 /* regshift */);
ops = kmalloc(sizeof(struct parport_operations), GFP_KERNEL);
priv = kmalloc(sizeof(struct parport_ip32_private), GFP_KERNEL);
p = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, ops);
if (ops == NULL || priv == NULL || p == NULL) {
err = -ENOMEM;
goto fail;
}
p->base = MACE_BASE + offsetof(struct sgi_mace, isa.parallel);
p->base_hi = MACE_BASE + offsetof(struct sgi_mace, isa.ecp1284);
p->private_data = priv;
*ops = parport_ip32_ops;
*priv = (struct parport_ip32_private){
.regs = regs,
.dcr_writable = DCR_DIR | DCR_SELECT | DCR_nINIT |
DCR_AUTOFD | DCR_STROBE,
.irq_mode = PARPORT_IP32_IRQ_FWD,
};
init_completion(&priv->irq_complete);
/* Probe port. */
if (!parport_ip32_ecp_supported(p)) {
err = -ENODEV;
goto fail;
}
parport_ip32_dump_state(p, "begin init", 0);
/* We found what looks like a working ECR register. Simply assume
* that all modes are correctly supported. Enable basic modes. */
p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
p->modes |= PARPORT_MODE_TRISTATE;
if (!parport_ip32_fifo_supported(p)) {
printk(KERN_WARNING PPIP32
"%s: error: FIFO disabled\n", p->name);
/* Disable hardware modes depending on a working FIFO. */
features &= ~PARPORT_IP32_ENABLE_SPP;
features &= ~PARPORT_IP32_ENABLE_ECP;
/* DMA is not needed if FIFO is not supported. */
features &= ~PARPORT_IP32_ENABLE_DMA;
}
/* Request IRQ */
if (features & PARPORT_IP32_ENABLE_IRQ) {
int irq = MACEISA_PARALLEL_IRQ;
if (request_irq(irq, parport_ip32_interrupt, 0, p->name, p)) {
printk(KERN_WARNING PPIP32
"%s: error: IRQ disabled\n", p->name);
/* DMA cannot work without interrupts. */
features &= ~PARPORT_IP32_ENABLE_DMA;
} else {
pr_probe(p, "Interrupt support enabled\n");
p->irq = irq;
priv->dcr_writable |= DCR_IRQ;
}
}
/* Allocate DMA resources */
if (features & PARPORT_IP32_ENABLE_DMA) {
if (parport_ip32_dma_register())
printk(KERN_WARNING PPIP32
"%s: error: DMA disabled\n", p->name);
else {
pr_probe(p, "DMA support enabled\n");
p->dma = 0; /* arbitrary value != PARPORT_DMA_NONE */
p->modes |= PARPORT_MODE_DMA;
}
}
if (features & PARPORT_IP32_ENABLE_SPP) {
/* Enable compatibility FIFO mode */
p->ops->compat_write_data = parport_ip32_compat_write_data;
p->modes |= PARPORT_MODE_COMPAT;
pr_probe(p, "Hardware support for SPP mode enabled\n");
}
if (features & PARPORT_IP32_ENABLE_EPP) {
/* Set up access functions to use EPP hardware. */
p->ops->epp_read_data = parport_ip32_epp_read_data;
p->ops->epp_write_data = parport_ip32_epp_write_data;
p->ops->epp_read_addr = parport_ip32_epp_read_addr;
p->ops->epp_write_addr = parport_ip32_epp_write_addr;
p->modes |= PARPORT_MODE_EPP;
pr_probe(p, "Hardware support for EPP mode enabled\n");
}
if (features & PARPORT_IP32_ENABLE_ECP) {
/* Enable ECP FIFO mode */
p->ops->ecp_write_data = parport_ip32_ecp_write_data;
/* FIXME - not implemented */
/* p->ops->ecp_read_data = parport_ip32_ecp_read_data; */
/* p->ops->ecp_write_addr = parport_ip32_ecp_write_addr; */
p->modes |= PARPORT_MODE_ECP;
pr_probe(p, "Hardware support for ECP mode enabled\n");
}
/* Initialize the port with sensible values */
parport_ip32_set_mode(p, ECR_MODE_PS2);
parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
parport_ip32_data_forward(p);
parport_ip32_disable_irq(p);
parport_ip32_write_data(p, 0x00);
parport_ip32_dump_state(p, "end init", 0);
/* Print out what we found */
printk(KERN_INFO "%s: SGI IP32 at 0x%lx (0x%lx)",
p->name, p->base, p->base_hi);
if (p->irq != PARPORT_IRQ_NONE)
printk(", irq %d", p->irq);
printk(" [");
#define printmode(x) if (p->modes & PARPORT_MODE_##x) \
printk("%s%s", f++ ? "," : "", #x)
{
unsigned int f = 0;
printmode(PCSPP);
printmode(TRISTATE);
printmode(COMPAT);
printmode(EPP);
printmode(ECP);
printmode(DMA);
}
#undef printmode
printk("]\n");
parport_announce_port(p);
return p;
fail:
if (p)
parport_put_port(p);
kfree(priv);
kfree(ops);
return ERR_PTR(err);
}
/**
* parport_ip32_unregister_port - unregister a parallel port
* @p: pointer to the &struct parport
*
* Unregisters a parallel port and free previously allocated resources
* (memory, IRQ, ...).
*/
static __exit void parport_ip32_unregister_port(struct parport *p)
{
struct parport_ip32_private * const priv = p->physport->private_data;
struct parport_operations *ops = p->ops;
parport_remove_port(p);
if (p->modes & PARPORT_MODE_DMA)
parport_ip32_dma_unregister();
if (p->irq != PARPORT_IRQ_NONE)
free_irq(p->irq, p);
parport_put_port(p);
kfree(priv);
kfree(ops);
}
/**
* parport_ip32_init - module initialization function
*/
static int __init parport_ip32_init(void)
{
pr_info(PPIP32 "SGI IP32 built-in parallel port driver v0.6\n");
pr_debug1(PPIP32 "Compiled on %s, %s\n", __DATE__, __TIME__);
this_port = parport_ip32_probe_port();
return IS_ERR(this_port) ? PTR_ERR(this_port) : 0;
}
/**
* parport_ip32_exit - module termination function
*/
static void __exit parport_ip32_exit(void)
{
parport_ip32_unregister_port(this_port);
}
/*--- Module stuff -----------------------------------------------------*/
MODULE_AUTHOR("Arnaud Giersch <arnaud.giersch@free.fr>");
MODULE_DESCRIPTION("SGI IP32 built-in parallel port driver");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.6"); /* update in parport_ip32_init() too */
module_init(parport_ip32_init);
module_exit(parport_ip32_exit);
module_param(verbose_probing, bool, S_IRUGO);
MODULE_PARM_DESC(verbose_probing, "Log chit-chat during initialization");
module_param(features, uint, S_IRUGO);
MODULE_PARM_DESC(features,
"Bit mask of features to enable"
", bit 0: IRQ support"
", bit 1: DMA support"
", bit 2: hardware SPP mode"
", bit 3: hardware EPP mode"
", bit 4: hardware ECP mode");
/*--- Inform (X)Emacs about preferred coding style ---------------------*/
/*
* Local Variables:
* mode: c
* c-file-style: "linux"
* indent-tabs-mode: t
* tab-width: 8
* fill-column: 78
* ispell-local-dictionary: "american"
* End:
*/
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