[PATCH 6/20] libata: implement legacy ATA init helpers

[Tejun Heo <htejun@gmail.com>]

Implement the following legacy ATA init helpers.

* ata_legacy_acquire_resources()	: acquire legacy ATA resources
* ata_legacy_release_resources()	: release legacy ATA resources
* ata_legacy_init_ports()		: init legacy port addresses
* ata_legacy_request_irqs()		: request legacy ATA IRQs
* ata_legacy_free_irqs()		: free legacy ATA IRQs

These helpers can be used independently or called implictly from other
bus helpers which has support for legacy ATA device for compatibility
(e.g. PCI).

Signed-off-by: Tejun Heo <htejun@gmail.com>
---
 drivers/ata/Kconfig         |    5 +
 drivers/ata/Makefile        |    3 +
 drivers/ata/libata-legacy.c |  241 +++++++++++++++++++++++++++++++++++++++++++
 drivers/ata/libata.h        |   11 ++
 include/linux/libata.h      |   15 ++-
 5 files changed, 273 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 2109d75..1a98559 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -15,6 +15,11 @@ config ATA
 	  that "speaks" the ATA protocol, also called ATA controller),
 	  because you will be asked for it.
 
+config ATA_LEGACY
+	bool
+	depends on ATA
+	default n
+
 config SATA_AHCI
 	tristate "AHCI SATA support"
 	depends on ATA && PCI
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index c17ae9c..61d3e76 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -19,3 +19,6 @@ obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
 
 libata-objs	:= libata-core.o libata-scsi.o libata-bmdma.o libata-eh.o
 
+ifeq ($(CONFIG_ATA_LEGACY),y)
+libata-objs	+= libata-legacy.o
+endif
diff --git a/drivers/ata/libata-legacy.c b/drivers/ata/libata-legacy.c
new file mode 100644
index 0000000..00b70b0
--- /dev/null
+++ b/drivers/ata/libata-legacy.c
@@ -0,0 +1,241 @@
+/*
+ *  libata-legacy.c - helper library for legacy ATA
+ *
+ *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
+ *    		    Please ALWAYS copy linux-ide@vger.kernel.org
+ *		    on emails.
+ *
+ *  Copyright 2006 Tejun Heo <htejun@gmail.com>
+ *
+ *
+ *  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, 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; see the file COPYING.  If not, write to
+ *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ *  USA.
+ *
+ *
+ *  libata documentation is available via 'make {ps|pdf}docs',
+ *  as Documentation/DocBook/libata.*
+ *
+ *  Hardware documentation available from http://www.t13.org/ and
+ *  http://www.sata-io.org/
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/libata.h>
+
+#include "libata.h"
+
+static unsigned long ata_legacy_addr(int port, int sel)
+{
+	if (port == 0) {
+		if (sel == 0)
+			return ATA_PRIMARY_CMD;
+		else
+			return ATA_PRIMARY_CTL;
+	} else {
+		if (sel == 0)
+			return ATA_SECONDARY_CMD;
+		else
+			return ATA_SECONDARY_CTL;
+	}
+}
+
+static int ata_legacy_acquire_port(struct ata_port *ap)
+{
+	struct ata_host *host = ap->host;
+	unsigned long cmd_addr = ata_legacy_addr(ap->port_no, 0);
+
+	if (request_region(cmd_addr, 8, "libata") != NULL)
+		host->legacy_flags |= ATA_LEGACY_RES_PRI << ap->port_no;
+	else {
+		struct resource *conflict, res;
+
+		res.start = cmd_addr;
+		res.end = cmd_addr + 8 - 1;
+		conflict = ____request_resource(&ioport_resource, &res);
+
+		if (strcmp(conflict->name, "libata")) {
+			printk(KERN_WARNING "ata: 0x%0lX IDE port busy\n",
+			       cmd_addr);
+			host->flags |= ATA_HOST_DEV_BUSY;
+			return -EBUSY;
+		}
+		printk("ata: 0x%0lX IDE port preallocated\n", cmd_addr);
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_legacy_acquire_resources - acquire legacy ATA resources
+ *	@host: target ATA host
+ *	@p_reason: out arg for error message (can be NULL)
+ *
+ *	Acquire legacy ATA resources for ports specified by
+ *	ATA_PORT_PRIMARY/SECONDARY mask in host->legacy_flags.  If the
+ *	port is busy, this function makes the port dummy instead of
+ *	failing.  This is to allow legacy ports to be driven by other
+ *	drivers.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer (may sleep).
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int ata_legacy_acquire_resources(struct ata_host *host, const char **p_reason)
+{
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		if (!(host->legacy_flags & (ATA_PORT_PRIMARY << i)))
+			continue;
+		BUG_ON(i >= host->n_ports);
+
+		if (ata_legacy_acquire_port(host->ports[i]))
+			host->ports[i]->ops = &ata_dummy_port_ops;
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_legacy_release_resources - release legacy ATA resources
+ *	@host: target ATA host
+ *
+ *	Free all legacy ATA resources @host is holding.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer (may sleep).
+ */
+void ata_legacy_release_resources(struct ata_host *host)
+{
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		if (host->legacy_flags & (ATA_LEGACY_RES_PRI << i)) {
+			release_region(ata_legacy_addr(i, 0), 8);
+			host->legacy_flags &= ~(ATA_LEGACY_RES_PRI << i);
+		}
+	}
+}
+
+/**
+ *	ata_legacy_init_ports - initialize legacy ATA port addresses
+ *	@host: target ATA host
+ *
+ *	Initialize legacy ATA port addresses for non-dummy legacy
+ *	ports in @host.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer.
+ */
+void ata_legacy_init_ports(struct ata_host *host)
+{
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		struct ata_port *ap = host->ports[i];
+
+		if (host->legacy_flags & (ATA_PORT_PRIMARY << i) &&
+		    !ata_port_is_dummy(ap)) {
+			struct ata_ioports *ioaddr = &ap->ioaddr;
+			unsigned long cmd_addr = ata_legacy_addr(i, 0);
+			unsigned long ctl_addr = ata_legacy_addr(i, 1);
+
+			ioaddr->cmd_addr = cmd_addr;
+			ioaddr->altstatus_addr = ctl_addr;
+			ioaddr->ctl_addr = ctl_addr;
+			ata_std_ports(ioaddr);
+		}
+	}
+}
+
+/**
+ *	ata_legacy_request_irqs - request legacy ATA IRQs
+ *	@host: target ATA host
+ *	@handler: array of IRQ handlers
+ *	@irq_flags: array of IRQ flags
+ *	@dev_id: array of IRQ dev_ids
+ *	@p_reason: out arg for error message (can be NULL)
+ *
+ *	Request legacy IRQs for non-dummy legacy ports in @host.  All
+ *	IRQ parameters are passed as array to allow ports to have
+ *	separate IRQ handlers.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer (may sleep).
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int ata_legacy_request_irqs(struct ata_host *host,
+		irqreturn_t (* const * handler)(int, void *, struct pt_regs *),
+		const unsigned int *irq_flags, void * const *dev_id,
+		const char **p_reason)
+{
+	const unsigned int legacy_irq[] = { 14, 15 };
+	const char *reason;
+	int i, rc;
+
+	for (i = 0; i < 2; i++) {
+		struct ata_port *ap = host->ports[i];
+		unsigned int irq = legacy_irq[i];
+
+		if (!(host->legacy_flags & (ATA_PORT_PRIMARY << i)) ||
+		    ata_port_is_dummy(ap))
+			continue;
+
+		if (!handler[i]) {
+			reason = "NULL handler";
+			rc = -EINVAL;
+			goto err;
+		}
+
+		rc = ata_host_request_irq_marker(host, irq,
+					handler[i], irq_flags[i], dev_id[i],
+					ata_legacy_request_irqs, &reason);
+		if (rc)
+			goto err;
+
+		/* only for info printing */
+		if (i == 0)
+			host->irq = irq;
+		else
+			host->irq2 = irq;
+	}
+
+	return 0;
+
+ err:
+	ata_legacy_free_irqs(host);
+	if (p_reason)
+		*p_reason = reason;
+	return rc;
+}
+
+/**
+ *	ata_legacy_free_irqs - free legacy ATA IRQs
+ *	@host: target ATA host
+ *
+ *	Free all legacy ATA IRQs of @host.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer (may sleep).
+ */
+void ata_legacy_free_irqs(struct ata_host *host)
+{
+	ata_host_free_irqs_marker(host, ata_legacy_request_irqs);
+}
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 1d24254..0601c4a 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -117,6 +117,17 @@ extern void ata_schedule_scsi_eh(struct 
 extern void ata_scsi_dev_rescan(void *data);
 extern int ata_bus_probe(struct ata_port *ap);
 
+/* libata-legacy.c */
+extern int ata_legacy_acquire_resources(struct ata_host *host,
+					const char **p_reason);
+extern void ata_legacy_release_resources(struct ata_host *host);
+extern void ata_legacy_init_ports(struct ata_host *host);
+extern int ata_legacy_request_irqs(struct ata_host *host,
+		irqreturn_t (* const * handler)(int, void *, struct pt_regs *),
+		const unsigned int *irq_flags, void * const *dev_id,
+		const char **p_reason);
+extern void ata_legacy_free_irqs(struct ata_host *host);
+
 /* libata-eh.c */
 extern enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd);
 extern void ata_scsi_error(struct Scsi_Host *host);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index b050517..9535f54 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -200,8 +200,16 @@ enum {
 	ATA_QCFLAG_EH_SCHEDULED = (1 << 18), /* EH scheduled (obsolete) */
 
 	/* host set flags */
-	ATA_HOST_SIMPLEX	= (1 << 0),	/* Host is simplex, one DMA channel per host only */
-	
+	ATA_HOST_SIMPLEX	= (1 << 0), /* host is simplex, one DMA channel per host only */
+	ATA_HOST_DEV_BUSY	= (1 << 1), /* host device was busy on init */
+
+	/* legacy flags */
+	/* BIT 0 and 1 are reserved for ATA_PORT_PRIMARY and SECONDARY */
+	ATA_LEGACY_MASK		= (1 << 0) | (1 << 1),
+
+	ATA_LEGACY_RES_PRI	= (1 << 8),
+	ATA_LEGACY_RES_SEC	= (1 << 9),
+
 	/* various lengths of time */
 	ATA_TMOUT_BOOT		= 30 * HZ,	/* heuristic */
 	ATA_TMOUT_BOOT_QUICK	= 7 * HZ,	/* heuristic */
@@ -376,8 +384,11 @@ struct ata_host {
 	void			*private_data;
 	const struct ata_port_operations *ops;
 	unsigned long		flags;
+
 	int			simplex_claimed;	/* Keep seperate in case we
 							   ever need to do this locked */
+	unsigned int		legacy_flags;
+
 	struct list_head	irq_list;	/* list of acquired irqs */
 	struct ata_port		*ports[0];
 };
-- 
1.4.1.1