[PATCH] ata: Generic platform_device libata driver

needs a changelog

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/Kconfig

@@ -499,6 +499,15 @@ config PATA_WINBOND_VLB
 	  Support for the Winbond W83759A controller on Vesa Local Bus
 	  systems.
 
+config PATA_PLATFORM
+	tristate "Generic platform device PATA support"
+	depends on EMBEDDED
+	help
+	  This option enables support for generic directly connected ATA
+	  devices commonly found on embedded systems.
+
+	  If unsure, say N.
+
 endif
 endmenu
 

drivers/ata/Makefile

@@ -55,6 +55,7 @@ obj-$(CONFIG_PATA_WINBOND)	+= pata_sl82c105.o
 obj-$(CONFIG_PATA_WINBOND_VLB)	+= pata_winbond.o
 obj-$(CONFIG_PATA_SIS)		+= pata_sis.o
 obj-$(CONFIG_PATA_TRIFLEX)	+= pata_triflex.o
+obj-$(CONFIG_PATA_PLATFORM)	+= pata_platform.o
 # Should be last but one libata driver
 obj-$(CONFIG_ATA_GENERIC)	+= ata_generic.o
 # Should be last libata driver

drivers/ata/pata_platform.c

@@ -0,0 +1,295 @@
+/*
+ * Generic platform device PATA driver
+ *
+ * Copyright (C) 2006  Paul Mundt
+ *
+ * Based on pata_pcmcia:
+ *
+ *   Copyright 2005-2006 Red Hat Inc <alan@redhat.com>, all rights reserved.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <scsi/scsi_host.h>
+#include <linux/ata.h>
+#include <linux/libata.h>
+#include <linux/platform_device.h>
+#include <linux/pata_platform.h>
+
+#define DRV_NAME "pata_platform"
+#define DRV_VERSION "0.1.2"
+
+static int pio_mask = 1;
+
+/*
+ * Provide our own set_mode() as we don't want to change anything that has
+ * already been configured..
+ */
+static void pata_platform_set_mode(struct ata_port *ap)
+{
+	int i;
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+
+		if (ata_dev_enabled(dev)) {
+			/* We don't really care */
+			dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
+			dev->xfer_shift = ATA_SHIFT_PIO;
+			dev->flags |= ATA_DFLAG_PIO;
+		}
+	}
+}
+
+static void pata_platform_host_stop(struct ata_host *host)
+{
+	int i;
+
+	/*
+	 * Unmap the bases for MMIO
+	 */
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap = host->ports[i];
+
+		if (ap->flags & ATA_FLAG_MMIO) {
+			iounmap((void __iomem *)ap->ioaddr.ctl_addr);
+			iounmap((void __iomem *)ap->ioaddr.cmd_addr);
+		}
+	}
+}
+
+static struct scsi_host_template pata_platform_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 pata_platform_port_ops = {
+	.set_mode		= pata_platform_set_mode,
+
+	.port_disable		= ata_port_disable,
+	.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		= ata_bmdma_error_handler,
+	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
+
+	.qc_prep		= ata_qc_prep,
+	.qc_issue		= ata_qc_issue_prot,
+
+	.data_xfer		= ata_pio_data_xfer_noirq,
+
+	.irq_handler		= ata_interrupt,
+	.irq_clear		= ata_bmdma_irq_clear,
+
+	.port_start		= ata_port_start,
+	.port_stop		= ata_port_stop,
+	.host_stop		= pata_platform_host_stop
+};
+
+static void pata_platform_setup_port(struct ata_ioports *ioaddr,
+				     struct pata_platform_info *info)
+{
+	unsigned int shift = 0;
+
+	/* Fixup the port shift for platforms that need it */
+	if (info && info->ioport_shift)
+		shift = info->ioport_shift;
+
+	ioaddr->data_addr	= ioaddr->cmd_addr + (ATA_REG_DATA    << shift);
+	ioaddr->error_addr	= ioaddr->cmd_addr + (ATA_REG_ERR     << shift);
+	ioaddr->feature_addr	= ioaddr->cmd_addr + (ATA_REG_FEATURE << shift);
+	ioaddr->nsect_addr	= ioaddr->cmd_addr + (ATA_REG_NSECT   << shift);
+	ioaddr->lbal_addr	= ioaddr->cmd_addr + (ATA_REG_LBAL    << shift);
+	ioaddr->lbam_addr	= ioaddr->cmd_addr + (ATA_REG_LBAM    << shift);
+	ioaddr->lbah_addr	= ioaddr->cmd_addr + (ATA_REG_LBAH    << shift);
+	ioaddr->device_addr	= ioaddr->cmd_addr + (ATA_REG_DEVICE  << shift);
+	ioaddr->status_addr	= ioaddr->cmd_addr + (ATA_REG_STATUS  << shift);
+	ioaddr->command_addr	= ioaddr->cmd_addr + (ATA_REG_CMD     << shift);
+}
+
+/**
+ *	pata_platform_probe		-	attach a platform interface
+ *	@pdev: platform device
+ *
+ *	Register a platform bus IDE interface. Such interfaces are PIO and we
+ *	assume do not support IRQ sharing.
+ *
+ *	Platform devices are expected to contain 3 resources per port:
+ *
+ *		- I/O Base (IORESOURCE_IO or IORESOURCE_MEM)
+ *		- CTL Base (IORESOURCE_IO or IORESOURCE_MEM)
+ *		- IRQ	   (IORESOURCE_IRQ)
+ *
+ *	If the base resources are both mem types, the ioremap() is handled
+ *	here. For IORESOURCE_IO, it's assumed that there's no remapping
+ *	necessary.
+ */
+static int __devinit pata_platform_probe(struct platform_device *pdev)
+{
+	struct resource *io_res, *ctl_res;
+	struct ata_probe_ent ae;
+	unsigned int mmio;
+	int ret;
+
+	/*
+	 * Simple resource validation ..
+	 */
+	if (unlikely(pdev->num_resources != 3)) {
+		dev_err(&pdev->dev, "invalid number of resources\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Get the I/O base first
+	 */
+	io_res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (io_res == NULL) {
+		io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+		if (unlikely(io_res == NULL))
+			return -EINVAL;
+	}
+
+	/*
+	 * Then the CTL base
+	 */
+	ctl_res = platform_get_resource(pdev, IORESOURCE_IO, 1);
+	if (ctl_res == NULL) {
+		ctl_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		if (unlikely(ctl_res == NULL))
+			return -EINVAL;
+	}
+
+	/*
+	 * Check for MMIO
+	 */
+	mmio = (( io_res->flags == IORESOURCE_MEM) &&
+		(ctl_res->flags == IORESOURCE_MEM));
+
+	/*
+	 * Now that that's out of the way, wire up the port..
+	 */
+	memset(&ae, 0, sizeof(struct ata_probe_ent));
+	INIT_LIST_HEAD(&ae.node);
+	ae.dev = &pdev->dev;
+	ae.port_ops = &pata_platform_port_ops;
+	ae.sht = &pata_platform_sht;
+	ae.n_ports = 1;
+	ae.pio_mask = pio_mask;
+	ae.irq = platform_get_irq(pdev, 0);
+	ae.irq_flags = 0;
+	ae.port_flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST;
+
+	/*
+	 * Handle the MMIO case
+	 */
+	if (mmio) {
+		ae.port_flags |= ATA_FLAG_MMIO;
+
+		ae.port[0].cmd_addr = (unsigned long)ioremap(io_res->start,
+				io_res->end - io_res->start + 1);
+		if (unlikely(!ae.port[0].cmd_addr)) {
+			dev_err(&pdev->dev, "failed to remap IO base\n");
+			return -ENXIO;
+		}
+
+		ae.port[0].ctl_addr = (unsigned long)ioremap(ctl_res->start,
+				ctl_res->end - ctl_res->start + 1);
+		if (unlikely(!ae.port[0].ctl_addr)) {
+			dev_err(&pdev->dev, "failed to remap CTL base\n");
+			ret = -ENXIO;
+			goto bad_remap;
+		}
+	} else {
+		ae.port[0].cmd_addr = io_res->start;
+		ae.port[0].ctl_addr = ctl_res->start;
+	}
+
+	ae.port[0].altstatus_addr = ae.port[0].ctl_addr;
+
+	pata_platform_setup_port(&ae.port[0], pdev->dev.platform_data);
+
+	if (unlikely(ata_device_add(&ae) == 0)) {
+		ret = -ENODEV;
+		goto add_failed;
+	}
+
+	return 0;
+
+add_failed:
+	if (ae.port[0].ctl_addr && mmio)
+		iounmap((void __iomem *)ae.port[0].ctl_addr);
+bad_remap:
+	if (ae.port[0].cmd_addr && mmio)
+		iounmap((void __iomem *)ae.port[0].cmd_addr);
+
+	return ret;
+}
+
+/**
+ *	pata_platform_remove	-	unplug a platform interface
+ *	@pdev: platform device
+ *
+ *	A platform bus ATA device has been unplugged. Perform the needed
+ *	cleanup. Also called on module unload for any active devices.
+ */
+static int __devexit pata_platform_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ata_host *host = dev_get_drvdata(dev);
+
+	ata_host_remove(host);
+	dev_set_drvdata(dev, NULL);
+
+	return 0;
+}
+
+static struct platform_driver pata_platform_driver = {
+	.probe		= pata_platform_probe,
+	.remove		= __devexit_p(pata_platform_remove),
+	.driver = {
+		.name		= DRV_NAME,
+		.owner		= THIS_MODULE,
+	},
+};
+
+static int __init pata_platform_init(void)
+{
+	return platform_driver_register(&pata_platform_driver);
+}
+
+static void __exit pata_platform_exit(void)
+{
+	platform_driver_unregister(&pata_platform_driver);
+}
+module_init(pata_platform_init);
+module_exit(pata_platform_exit);
+
+module_param(pio_mask, int, 0);
+
+MODULE_AUTHOR("Paul Mundt");
+MODULE_DESCRIPTION("low-level driver for platform device ATA");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);

include/linux/pata_platform.h

@@ -0,0 +1,13 @@
+#ifndef __LINUX_PATA_PLATFORM_H
+#define __LINUX_PATA_PLATFORM_H
+
+struct pata_platform_info {
+	/*
+	 * I/O port shift, for platforms with ports that are
+	 * constantly spaced and need larger than the 1-byte
+	 * spacing used by ata_std_ports().
+	 */
+	unsigned int ioport_shift;
+};
+
+#endif /* __LINUX_PATA_PLATFORM_H */