kernel-ark/drivers/spi/dw_spi_pci.c
Feng Tang 552e450929 spi/dw_spi: refine the IRQ mode working flow
Now dw_spi core fully supports 3 transfer modes: pure polling,
DMA and IRQ mode. IRQ mode will use the FIFO half empty as
the IRQ trigger, so each interface driver need set the fifo_len,
so that core driver can handle it properly

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-01-20 13:49:45 -07:00

172 lines
4.0 KiB
C

/*
* mrst_spi_pci.c - PCI interface driver for DW SPI Core
*
* Copyright (c) 2009, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/spi/dw_spi.h>
#include <linux/spi/spi.h>
#define DRIVER_NAME "dw_spi_pci"
struct dw_spi_pci {
struct pci_dev *pdev;
struct dw_spi dws;
};
static int __devinit spi_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
struct dw_spi_pci *dwpci;
struct dw_spi *dws;
int pci_bar = 0;
int ret;
printk(KERN_INFO "DW: found PCI SPI controller(ID: %04x:%04x)\n",
pdev->vendor, pdev->device);
ret = pci_enable_device(pdev);
if (ret)
return ret;
dwpci = kzalloc(sizeof(struct dw_spi_pci), GFP_KERNEL);
if (!dwpci) {
ret = -ENOMEM;
goto err_disable;
}
dwpci->pdev = pdev;
dws = &dwpci->dws;
/* Get basic io resource and map it */
dws->paddr = pci_resource_start(pdev, pci_bar);
dws->iolen = pci_resource_len(pdev, pci_bar);
ret = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
if (ret)
goto err_kfree;
dws->regs = ioremap_nocache((unsigned long)dws->paddr,
pci_resource_len(pdev, pci_bar));
if (!dws->regs) {
ret = -ENOMEM;
goto err_release_reg;
}
dws->parent_dev = &pdev->dev;
dws->bus_num = 0;
dws->num_cs = 4;
dws->max_freq = 25000000; /* for Moorestwon */
dws->irq = pdev->irq;
dws->fifo_len = 40; /* FIFO has 40 words buffer */
ret = dw_spi_add_host(dws);
if (ret)
goto err_unmap;
/* PCI hook and SPI hook use the same drv data */
pci_set_drvdata(pdev, dwpci);
return 0;
err_unmap:
iounmap(dws->regs);
err_release_reg:
pci_release_region(pdev, pci_bar);
err_kfree:
kfree(dwpci);
err_disable:
pci_disable_device(pdev);
return ret;
}
static void __devexit spi_pci_remove(struct pci_dev *pdev)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
pci_set_drvdata(pdev, NULL);
dw_spi_remove_host(&dwpci->dws);
iounmap(dwpci->dws.regs);
pci_release_region(pdev, 0);
kfree(dwpci);
pci_disable_device(pdev);
}
#ifdef CONFIG_PM
static int spi_suspend(struct pci_dev *pdev, pm_message_t state)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
int ret;
ret = dw_spi_suspend_host(&dwpci->dws);
if (ret)
return ret;
pci_save_state(pdev);
pci_disable_device(pdev);
pci_set_power_state(pdev, pci_choose_state(pdev, state));
return ret;
}
static int spi_resume(struct pci_dev *pdev)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
int ret;
pci_set_power_state(pdev, PCI_D0);
pci_restore_state(pdev);
ret = pci_enable_device(pdev);
if (ret)
return ret;
return dw_spi_resume_host(&dwpci->dws);
}
#else
#define spi_suspend NULL
#define spi_resume NULL
#endif
static const struct pci_device_id pci_ids[] __devinitdata = {
/* Intel Moorestown platform SPI controller 0 */
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0800) },
{},
};
static struct pci_driver dw_spi_driver = {
.name = DRIVER_NAME,
.id_table = pci_ids,
.probe = spi_pci_probe,
.remove = __devexit_p(spi_pci_remove),
.suspend = spi_suspend,
.resume = spi_resume,
};
static int __init mrst_spi_init(void)
{
return pci_register_driver(&dw_spi_driver);
}
static void __exit mrst_spi_exit(void)
{
pci_unregister_driver(&dw_spi_driver);
}
module_init(mrst_spi_init);
module_exit(mrst_spi_exit);
MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
MODULE_DESCRIPTION("PCI interface driver for DW SPI Core");
MODULE_LICENSE("GPL v2");