[libata] Add a bunch of PATA drivers.

The vast majority of drivers and changes are from Alan Cox.  Albert Lee
contributed and maintains pata_pdc2027x.  Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_mpiix.c b/drivers/ata/pata_mpiix.c
new file mode 100644
index 0000000..1958c4e
--- /dev/null
+++ b/drivers/ata/pata_mpiix.c
@@ -0,0 +1,313 @@
+/*
+ * pata_mpiix.c 	- Intel MPIIX PATA for new ATA layer
+ *			  (C) 2005-2006 Red Hat Inc
+ *			  Alan Cox <alan@redhat.com>
+ *
+ * The MPIIX is different enough to the PIIX4 and friends that we give it
+ * a separate driver. The old ide/pci code handles this by just not tuning
+ * MPIIX at all.
+ *
+ * The MPIIX also differs in another important way from the majority of PIIX
+ * devices. The chip is a bridge (pardon the pun) between the old world of
+ * ISA IDE and PCI IDE. Although the ATA timings are PCI configured the actual
+ * IDE controller is not decoded in PCI space and the chip does not claim to
+ * be IDE class PCI. This requires slightly non-standard probe logic compared
+ * with PCI IDE and also that we do not disable the device when our driver is
+ * unloaded (as it has many other functions).
+ *
+ * The driver conciously keeps this logic internally to avoid pushing quirky
+ * PATA history into the clean libata layer.
+ *
+ * Thinkpad specific note: If you boot an MPIIX using thinkpad with a PCMCIA
+ * hard disk present this driver will not detect it. This is not a bug. In this
+ * configuration the secondary port of the MPIIX is disabled and the addresses
+ * are decoded by the PCMCIA bridge and therefore are for a generic IDE driver
+ * to operate.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <scsi/scsi_host.h>
+#include <linux/libata.h>
+
+#define DRV_NAME "pata_mpiix"
+#define DRV_VERSION "0.7.1"
+
+enum {
+	IDETIM = 0x6C,		/* IDE control register */
+	IORDY = (1 << 1),
+	PPE = (1 << 2),
+	FTIM = (1 << 0),
+	ENABLED = (1 << 15),
+	SECONDARY = (1 << 14)
+};
+
+static int mpiix_pre_reset(struct ata_port *ap)
+{
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	static const struct pci_bits mpiix_enable_bits[] = {
+		{ 0x6D, 1, 0x80, 0x80 },
+		{ 0x6F, 1, 0x80, 0x80 }
+	};
+
+	if (!pci_test_config_bits(pdev, &mpiix_enable_bits[ap->port_no])) {
+		ata_port_disable(ap);
+		printk(KERN_INFO "ata%u: port disabled. ignoring.\n", ap->id);
+		return 0;
+	}
+	ap->cbl = ATA_CBL_PATA40;
+	return ata_std_prereset(ap);
+}
+
+/**
+ *	mpiix_error_handler		-	probe reset
+ *	@ap: ATA port
+ *
+ *	Perform the ATA probe and bus reset sequence plus specific handling
+ *	for this hardware. The MPIIX has the enable bits in a different place
+ *	to PIIX4 and friends. As a pure PIO device it has no cable detect
+ */
+
+static void mpiix_error_handler(struct ata_port *ap)
+{
+	ata_bmdma_drive_eh(ap, mpiix_pre_reset, ata_std_softreset, NULL, ata_std_postreset);
+}
+
+/**
+ *	mpiix_set_piomode	-	set initial PIO mode data
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *
+ *	Called to do the PIO mode setup. The MPIIX allows us to program the
+ *	IORDY sample point (2-5 clocks), recovery 1-4 clocks and whether
+ *	prefetching or iordy are used.
+ *
+ *	This would get very ugly because we can only program timing for one
+ *	device at a time, the other gets PIO0. Fortunately libata calls
+ *	our qc_issue_prot command before a command is issued so we can
+ *	flip the timings back and forth to reduce the pain.
+ */
+
+static void mpiix_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+	int control = 0;
+	int pio = adev->pio_mode - XFER_PIO_0;
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	u16 idetim;
+	static const	 /* ISP  RTC */
+	u8 timings[][2]	= { { 0, 0 },
+			    { 0, 0 },
+			    { 1, 0 },
+			    { 2, 1 },
+			    { 2, 3 }, };
+
+	pci_read_config_word(pdev, IDETIM, &idetim);
+	/* Mask the IORDY/TIME/PPE0 bank for this device */
+	if (adev->class == ATA_DEV_ATA)
+		control |= PPE;		/* PPE enable for disk */
+	if (ata_pio_need_iordy(adev))
+		control |= IORDY;	/* IORDY */
+	if (pio > 0)
+		control |= FTIM;	/* This drive is on the fast timing bank */
+
+	/* Mask out timing and clear both TIME bank selects */
+	idetim &= 0xCCEE;
+	idetim &= ~(0x07  << (2 * adev->devno));
+	idetim |= (control << (2 * adev->devno));
+
+	idetim |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
+	pci_write_config_word(pdev, IDETIM, idetim);
+
+	/* We use ap->private_data as a pointer to the device currently
+	   loaded for timing */
+	ap->private_data = adev;
+}
+
+/**
+ *	mpiix_qc_issue_prot	-	command issue
+ *	@qc: command pending
+ *
+ *	Called when the libata layer is about to issue a command. We wrap
+ *	this interface so that we can load the correct ATA timings if
+ *	neccessary. Our logic also clears TIME0/TIME1 for the other device so
+ *	that, even if we get this wrong, cycles to the other device will
+ *	be made PIO0.
+ */
+
+static unsigned int mpiix_qc_issue_prot(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct ata_device *adev = qc->dev;
+
+	/* If modes have been configured and the channel data is not loaded
+	   then load it. We have to check if pio_mode is set as the core code
+	   does not set adev->pio_mode to XFER_PIO_0 while probing as would be
+	   logical */
+
+	if (adev->pio_mode && adev != ap->private_data)
+		mpiix_set_piomode(ap, adev);
+
+	return ata_qc_issue_prot(qc);
+}
+
+static struct scsi_host_template mpiix_sht = {
+	.module			= THIS_MODULE,
+	.name			= DRV_NAME,
+	.ioctl			= ata_scsi_ioctl,
+	.queuecommand		= ata_scsi_queuecmd,
+	.can_queue		= ATA_DEF_QUEUE,
+	.this_id		= ATA_SHT_THIS_ID,
+	.sg_tablesize		= LIBATA_MAX_PRD,
+	.max_sectors		= ATA_MAX_SECTORS,
+	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
+	.emulated		= ATA_SHT_EMULATED,
+	.use_clustering		= ATA_SHT_USE_CLUSTERING,
+	.proc_name		= DRV_NAME,
+	.dma_boundary		= ATA_DMA_BOUNDARY,
+	.slave_configure	= ata_scsi_slave_config,
+	.bios_param		= ata_std_bios_param,
+};
+
+static struct ata_port_operations mpiix_port_ops = {
+	.port_disable	= ata_port_disable,
+	.set_piomode	= mpiix_set_piomode,
+
+	.tf_load	= ata_tf_load,
+	.tf_read	= ata_tf_read,
+	.check_status 	= ata_check_status,
+	.exec_command	= ata_exec_command,
+	.dev_select 	= ata_std_dev_select,
+
+	.freeze		= ata_bmdma_freeze,
+	.thaw		= ata_bmdma_thaw,
+	.error_handler	= mpiix_error_handler,
+	.post_internal_cmd = ata_bmdma_post_internal_cmd,
+
+	.qc_prep 	= ata_qc_prep,
+	.qc_issue	= mpiix_qc_issue_prot,
+	.data_xfer	= ata_pio_data_xfer,
+
+	.irq_handler	= ata_interrupt,
+	.irq_clear	= ata_bmdma_irq_clear,
+
+	.port_start	= ata_port_start,
+	.port_stop	= ata_port_stop,
+	.host_stop	= ata_host_stop
+};
+
+static int mpiix_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	/* Single threaded by the PCI probe logic */
+	static struct ata_probe_ent probe[2];
+	static int printed_version;
+	u16 idetim;
+	int enabled;
+
+	if (!printed_version++)
+		dev_printk(KERN_DEBUG, &dev->dev, "version " DRV_VERSION "\n");
+
+	/* MPIIX has many functions which can be turned on or off according
+	   to other devices present. Make sure IDE is enabled before we try
+	   and use it */
+
+	pci_read_config_word(dev, IDETIM, &idetim);
+	if (!(idetim & ENABLED))
+		return -ENODEV;
+
+	/* We do our own plumbing to avoid leaking special cases for whacko
+	   ancient hardware into the core code. There are two issues to
+	   worry about.  #1 The chip is a bridge so if in legacy mode and
+	   without BARs set fools the setup.  #2 If you pci_disable_device
+	   the MPIIX your box goes castors up */
+
+	INIT_LIST_HEAD(&probe[0].node);
+	probe[0].dev = pci_dev_to_dev(dev);
+	probe[0].port_ops = &mpiix_port_ops;
+	probe[0].sht = &mpiix_sht;
+	probe[0].pio_mask = 0x1F;
+	probe[0].irq = 14;
+	probe[0].irq_flags = SA_SHIRQ;
+	probe[0].port_flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST;
+	probe[0].n_ports = 1;
+	probe[0].port[0].cmd_addr = 0x1F0;
+	probe[0].port[0].ctl_addr = 0x3F6;
+	probe[0].port[0].altstatus_addr = 0x3F6;
+
+	/* The secondary lurks at different addresses but is otherwise
+	   the same beastie */
+
+	INIT_LIST_HEAD(&probe[1].node);
+	probe[1] = probe[0];
+	probe[1].irq = 15;
+	probe[1].port[0].cmd_addr = 0x170;
+	probe[1].port[0].ctl_addr = 0x376;
+	probe[1].port[0].altstatus_addr = 0x376;
+
+	/* Let libata fill in the port details */
+	ata_std_ports(&probe[0].port[0]);
+	ata_std_ports(&probe[1].port[0]);
+
+	/* Now add the port that is active */
+	enabled = (idetim & SECONDARY) ? 1 : 0;
+
+	if (ata_device_add(&probe[enabled]))
+		return 0;
+	return -ENODEV;
+}
+
+/**
+ *	mpiix_remove_one	-	device unload
+ *	@pdev: PCI device being removed
+ *
+ *	Handle an unplug/unload event for a PCI device. Unload the
+ *	PCI driver but do not use the default handler as we *MUST NOT*
+ *	disable the device as it has other functions.
+ */
+
+static void __devexit mpiix_remove_one(struct pci_dev *pdev)
+{
+	struct device *dev = pci_dev_to_dev(pdev);
+	struct ata_host *host = dev_get_drvdata(dev);
+
+	ata_host_remove(host);
+	dev_set_drvdata(dev, NULL);
+}
+
+
+
+static const struct pci_device_id mpiix[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371MX), },
+	{ 0, },
+};
+
+static struct pci_driver mpiix_pci_driver = {
+	.name 		= DRV_NAME,
+	.id_table	= mpiix,
+	.probe 		= mpiix_init_one,
+	.remove		= mpiix_remove_one
+};
+
+static int __init mpiix_init(void)
+{
+	return pci_register_driver(&mpiix_pci_driver);
+}
+
+
+static void __exit mpiix_exit(void)
+{
+	pci_unregister_driver(&mpiix_pci_driver);
+}
+
+
+MODULE_AUTHOR("Alan Cox");
+MODULE_DESCRIPTION("low-level driver for Intel MPIIX");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, mpiix);
+MODULE_VERSION(DRV_VERSION);
+
+module_init(mpiix_init);
+module_exit(mpiix_exit);