linux/drivers/dma/dw/pci.c
Chew, Chiau Ee 4501fe61b2 dma: dw: Add suspend and resume handling for PCI mode DW_DMAC.
This is to disable/enable DW_DMAC hw during late suspend/early resume.
Since DMA is providing service to other clients (eg: SPI, HSUART),
we need to ensure DMA suspends after the clients and resume
before the clients are active.

Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-03-26 11:52:03 +05:30

138 lines
3.2 KiB
C

/*
* PCI driver for the Synopsys DesignWare DMA Controller
*
* Copyright (C) 2013 Intel Corporation
* Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/device.h>
#include "internal.h"
static struct dw_dma_platform_data dw_pci_pdata = {
.is_private = 1,
.chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
.chan_priority = CHAN_PRIORITY_ASCENDING,
};
static int dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *pid)
{
struct dw_dma_chip *chip;
struct dw_dma_platform_data *pdata = (void *)pid->driver_data;
int ret;
ret = pcim_enable_device(pdev);
if (ret)
return ret;
ret = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
if (ret) {
dev_err(&pdev->dev, "I/O memory remapping failed\n");
return ret;
}
pci_set_master(pdev);
pci_try_set_mwi(pdev);
ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (ret)
return ret;
ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
if (ret)
return ret;
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = &pdev->dev;
chip->regs = pcim_iomap_table(pdev)[0];
chip->irq = pdev->irq;
ret = dw_dma_probe(chip, pdata);
if (ret)
return ret;
pci_set_drvdata(pdev, chip);
return 0;
}
static void dw_pci_remove(struct pci_dev *pdev)
{
struct dw_dma_chip *chip = pci_get_drvdata(pdev);
int ret;
ret = dw_dma_remove(chip);
if (ret)
dev_warn(&pdev->dev, "can't remove device properly: %d\n", ret);
}
#ifdef CONFIG_PM_SLEEP
static int dw_pci_suspend_late(struct device *dev)
{
struct pci_dev *pci = to_pci_dev(dev);
struct dw_dma_chip *chip = pci_get_drvdata(pci);
return dw_dma_suspend(chip);
};
static int dw_pci_resume_early(struct device *dev)
{
struct pci_dev *pci = to_pci_dev(dev);
struct dw_dma_chip *chip = pci_get_drvdata(pci);
return dw_dma_resume(chip);
};
#else /* !CONFIG_PM_SLEEP */
#define dw_pci_suspend_late NULL
#define dw_pci_resume_early NULL
#endif /* !CONFIG_PM_SLEEP */
static const struct dev_pm_ops dw_pci_dev_pm_ops = {
.suspend_late = dw_pci_suspend_late,
.resume_early = dw_pci_resume_early,
};
static DEFINE_PCI_DEVICE_TABLE(dw_pci_id_table) = {
/* Medfield */
{ PCI_VDEVICE(INTEL, 0x0827), (kernel_ulong_t)&dw_pci_pdata },
{ PCI_VDEVICE(INTEL, 0x0830), (kernel_ulong_t)&dw_pci_pdata },
/* BayTrail */
{ PCI_VDEVICE(INTEL, 0x0f06), (kernel_ulong_t)&dw_pci_pdata },
{ PCI_VDEVICE(INTEL, 0x0f40), (kernel_ulong_t)&dw_pci_pdata },
/* Haswell */
{ PCI_VDEVICE(INTEL, 0x9c60), (kernel_ulong_t)&dw_pci_pdata },
{ }
};
MODULE_DEVICE_TABLE(pci, dw_pci_id_table);
static struct pci_driver dw_pci_driver = {
.name = "dw_dmac_pci",
.id_table = dw_pci_id_table,
.probe = dw_pci_probe,
.remove = dw_pci_remove,
.driver = {
.pm = &dw_pci_dev_pm_ops,
},
};
module_pci_driver(dw_pci_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller PCI driver");
MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");