linux/drivers/ata/ahci_platform.c
Brian Norris 941c77fd0f ahci_platform: enable hotplug unbinding
platform_driver_probe() should be used for registering this driver only
if we want to

    "...remove its run-once probe() infrastructure from memory after the
    driver has bound to the device."

However, we may want to leave the probe infrastructure in place in order
to support binding/unbinding a device dynamically. This is useful, for
instance, as a power management mechanism, where a device can be totally
powered down when unbound (whereas with runtime power management,
powering down the SATA core would incur unacceptable loss of
functionality).

Thus, convert this driver to use platform_driver_register().

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2012-12-03 05:14:07 -05:00

356 lines
8 KiB
C

/*
* AHCI SATA platform driver
*
* Copyright 2004-2005 Red Hat, Inc.
* Jeff Garzik <jgarzik@pobox.com>
* Copyright 2010 MontaVista Software, LLC.
* Anton Vorontsov <avorontsov@ru.mvista.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.
*/
#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/libata.h>
#include <linux/ahci_platform.h>
#include "ahci.h"
enum ahci_type {
AHCI, /* standard platform ahci */
IMX53_AHCI, /* ahci on i.mx53 */
STRICT_AHCI, /* delayed DMA engine start */
};
static struct platform_device_id ahci_devtype[] = {
{
.name = "ahci",
.driver_data = AHCI,
}, {
.name = "imx53-ahci",
.driver_data = IMX53_AHCI,
}, {
.name = "strict-ahci",
.driver_data = STRICT_AHCI,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(platform, ahci_devtype);
static const struct ata_port_info ahci_port_info[] = {
/* by features */
[AHCI] = {
.flags = AHCI_FLAG_COMMON,
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_ops,
},
[IMX53_AHCI] = {
.flags = AHCI_FLAG_COMMON,
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_pmp_retry_srst_ops,
},
[STRICT_AHCI] = {
AHCI_HFLAGS (AHCI_HFLAG_DELAY_ENGINE),
.flags = AHCI_FLAG_COMMON,
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_ops,
},
};
static struct scsi_host_template ahci_platform_sht = {
AHCI_SHT("ahci_platform"),
};
static int __devinit ahci_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ahci_platform_data *pdata = dev_get_platdata(dev);
const struct platform_device_id *id = platform_get_device_id(pdev);
struct ata_port_info pi = ahci_port_info[id ? id->driver_data : 0];
const struct ata_port_info *ppi[] = { &pi, NULL };
struct ahci_host_priv *hpriv;
struct ata_host *host;
struct resource *mem;
int irq;
int n_ports;
int i;
int rc;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(dev, "no mmio space\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
if (irq <= 0) {
dev_err(dev, "no irq\n");
return -EINVAL;
}
if (pdata && pdata->ata_port_info)
pi = *pdata->ata_port_info;
hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
if (!hpriv) {
dev_err(dev, "can't alloc ahci_host_priv\n");
return -ENOMEM;
}
hpriv->flags |= (unsigned long)pi.private_data;
hpriv->mmio = devm_ioremap(dev, mem->start, resource_size(mem));
if (!hpriv->mmio) {
dev_err(dev, "can't map %pR\n", mem);
return -ENOMEM;
}
hpriv->clk = clk_get(dev, NULL);
if (IS_ERR(hpriv->clk)) {
dev_err(dev, "can't get clock\n");
} else {
rc = clk_prepare_enable(hpriv->clk);
if (rc) {
dev_err(dev, "clock prepare enable failed");
goto free_clk;
}
}
/*
* Some platforms might need to prepare for mmio region access,
* which could be done in the following init call. So, the mmio
* region shouldn't be accessed before init (if provided) has
* returned successfully.
*/
if (pdata && pdata->init) {
rc = pdata->init(dev, hpriv->mmio);
if (rc)
goto disable_unprepare_clk;
}
ahci_save_initial_config(dev, hpriv,
pdata ? pdata->force_port_map : 0,
pdata ? pdata->mask_port_map : 0);
/* prepare host */
if (hpriv->cap & HOST_CAP_NCQ)
pi.flags |= ATA_FLAG_NCQ;
if (hpriv->cap & HOST_CAP_PMP)
pi.flags |= ATA_FLAG_PMP;
ahci_set_em_messages(hpriv, &pi);
/* CAP.NP sometimes indicate the index of the last enabled
* port, at other times, that of the last possible port, so
* determining the maximum port number requires looking at
* both CAP.NP and port_map.
*/
n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
host = ata_host_alloc_pinfo(dev, ppi, n_ports);
if (!host) {
rc = -ENOMEM;
goto pdata_exit;
}
host->private_data = hpriv;
if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
host->flags |= ATA_HOST_PARALLEL_SCAN;
else
printk(KERN_INFO "ahci: SSS flag set, parallel bus scan disabled\n");
if (pi.flags & ATA_FLAG_EM)
ahci_reset_em(host);
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
ata_port_desc(ap, "mmio %pR", mem);
ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
/* set enclosure management message type */
if (ap->flags & ATA_FLAG_EM)
ap->em_message_type = hpriv->em_msg_type;
/* disabled/not-implemented port */
if (!(hpriv->port_map & (1 << i)))
ap->ops = &ata_dummy_port_ops;
}
rc = ahci_reset_controller(host);
if (rc)
goto pdata_exit;
ahci_init_controller(host);
ahci_print_info(host, "platform");
rc = ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
&ahci_platform_sht);
if (rc)
goto pdata_exit;
return 0;
pdata_exit:
if (pdata && pdata->exit)
pdata->exit(dev);
disable_unprepare_clk:
if (!IS_ERR(hpriv->clk))
clk_disable_unprepare(hpriv->clk);
free_clk:
if (!IS_ERR(hpriv->clk))
clk_put(hpriv->clk);
return rc;
}
static int __devexit ahci_remove(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ahci_platform_data *pdata = dev_get_platdata(dev);
struct ata_host *host = dev_get_drvdata(dev);
struct ahci_host_priv *hpriv = host->private_data;
ata_host_detach(host);
if (pdata && pdata->exit)
pdata->exit(dev);
if (!IS_ERR(hpriv->clk)) {
clk_disable_unprepare(hpriv->clk);
clk_put(hpriv->clk);
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int ahci_suspend(struct device *dev)
{
struct ahci_platform_data *pdata = dev_get_platdata(dev);
struct ata_host *host = dev_get_drvdata(dev);
struct ahci_host_priv *hpriv = host->private_data;
void __iomem *mmio = hpriv->mmio;
u32 ctl;
int rc;
if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
dev_err(dev, "firmware update required for suspend/resume\n");
return -EIO;
}
/*
* AHCI spec rev1.1 section 8.3.3:
* Software must disable interrupts prior to requesting a
* transition of the HBA to D3 state.
*/
ctl = readl(mmio + HOST_CTL);
ctl &= ~HOST_IRQ_EN;
writel(ctl, mmio + HOST_CTL);
readl(mmio + HOST_CTL); /* flush */
rc = ata_host_suspend(host, PMSG_SUSPEND);
if (rc)
return rc;
if (pdata && pdata->suspend)
return pdata->suspend(dev);
if (!IS_ERR(hpriv->clk))
clk_disable_unprepare(hpriv->clk);
return 0;
}
static int ahci_resume(struct device *dev)
{
struct ahci_platform_data *pdata = dev_get_platdata(dev);
struct ata_host *host = dev_get_drvdata(dev);
struct ahci_host_priv *hpriv = host->private_data;
int rc;
if (!IS_ERR(hpriv->clk)) {
rc = clk_prepare_enable(hpriv->clk);
if (rc) {
dev_err(dev, "clock prepare enable failed");
return rc;
}
}
if (pdata && pdata->resume) {
rc = pdata->resume(dev);
if (rc)
goto disable_unprepare_clk;
}
if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
rc = ahci_reset_controller(host);
if (rc)
goto disable_unprepare_clk;
ahci_init_controller(host);
}
ata_host_resume(host);
return 0;
disable_unprepare_clk:
if (!IS_ERR(hpriv->clk))
clk_disable_unprepare(hpriv->clk);
return rc;
}
#endif
SIMPLE_DEV_PM_OPS(ahci_pm_ops, ahci_suspend, ahci_resume);
static const struct of_device_id ahci_of_match[] = {
{ .compatible = "snps,spear-ahci", },
{},
};
MODULE_DEVICE_TABLE(of, ahci_of_match);
static struct platform_driver ahci_driver = {
.probe = ahci_probe,
.remove = __devexit_p(ahci_remove),
.driver = {
.name = "ahci",
.owner = THIS_MODULE,
.of_match_table = ahci_of_match,
.pm = &ahci_pm_ops,
},
.id_table = ahci_devtype,
};
static int __init ahci_init(void)
{
return platform_driver_register(&ahci_driver);
}
module_init(ahci_init);
static void __exit ahci_exit(void)
{
platform_driver_unregister(&ahci_driver);
}
module_exit(ahci_exit);
MODULE_DESCRIPTION("AHCI SATA platform driver");
MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ahci");