linux-stable/drivers/dma/acpi-dma.c

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// SPDX-License-Identifier: GPL-2.0-only
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
/*
* ACPI helpers for DMA request / controller
*
* Based on of-dma.c
*
* Copyright (C) 2013, Intel Corporation
* Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
#include <linux/module.h>
#include <linux/kernel.h>
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/ioport.h>
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
#include <linux/acpi.h>
#include <linux/acpi_dma.h>
#include <linux/property.h>
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
static LIST_HEAD(acpi_dma_list);
static DEFINE_MUTEX(acpi_dma_lock);
/**
* acpi_dma_parse_resource_group - match device and parse resource group
* @grp: CSRT resource group
* @adev: ACPI device to match with
* @adma: struct acpi_dma of the given DMA controller
*
* In order to match a device from DSDT table to the corresponding CSRT device
* we use MMIO address and IRQ.
*
* Return:
* 1 on success, 0 when no information is available, or appropriate errno value
* on error.
*/
static int acpi_dma_parse_resource_group(const struct acpi_csrt_group *grp,
struct acpi_device *adev, struct acpi_dma *adma)
{
const struct acpi_csrt_shared_info *si;
struct list_head resource_list;
struct resource_entry *rentry;
resource_size_t mem = 0, irq = 0;
int ret;
if (grp->shared_info_length != sizeof(struct acpi_csrt_shared_info))
return -ENODEV;
INIT_LIST_HEAD(&resource_list);
ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
if (ret <= 0)
return 0;
list_for_each_entry(rentry, &resource_list, node) {
if (resource_type(rentry->res) == IORESOURCE_MEM)
mem = rentry->res->start;
else if (resource_type(rentry->res) == IORESOURCE_IRQ)
irq = rentry->res->start;
}
acpi_dev_free_resource_list(&resource_list);
/* Consider initial zero values as resource not found */
if (mem == 0 && irq == 0)
return 0;
si = (const struct acpi_csrt_shared_info *)&grp[1];
/* Match device by MMIO */
if (si->mmio_base_low != lower_32_bits(mem) ||
si->mmio_base_high != upper_32_bits(mem))
return 0;
/*
* acpi_gsi_to_irq() can't be used because some platforms do not save
* registered IRQs in the MP table. Instead we just try to register
* the GSI, which is the core part of the above mentioned function.
*/
ret = acpi_register_gsi(NULL, si->gsi_interrupt, si->interrupt_mode, si->interrupt_polarity);
if (ret < 0)
return 0;
/* Match device by Linux vIRQ */
if (ret != irq)
return 0;
dev_dbg(&adev->dev, "matches with %.4s%04X (rev %u)\n",
(char *)&grp->vendor_id, grp->device_id, grp->revision);
/* Check if the request line range is available */
if (si->base_request_line == 0 && si->num_handshake_signals == 0)
return 0;
/* Set up DMA mask based on value from CSRT */
ret = dma_coerce_mask_and_coherent(&adev->dev,
DMA_BIT_MASK(si->dma_address_width));
if (ret)
return 0;
adma->base_request_line = si->base_request_line;
adma->end_request_line = si->base_request_line +
si->num_handshake_signals - 1;
dev_dbg(&adev->dev, "request line base: 0x%04x end: 0x%04x\n",
adma->base_request_line, adma->end_request_line);
return 1;
}
/**
* acpi_dma_parse_csrt - parse CSRT to exctract additional DMA resources
* @adev: ACPI device to match with
* @adma: struct acpi_dma of the given DMA controller
*
* CSRT or Core System Resources Table is a proprietary ACPI table
* introduced by Microsoft. This table can contain devices that are not in
* the system DSDT table. In particular DMA controllers might be described
* here.
*
* We are using this table to get the request line range of the specific DMA
* controller to be used later.
*/
static void acpi_dma_parse_csrt(struct acpi_device *adev, struct acpi_dma *adma)
{
struct acpi_csrt_group *grp, *end;
struct acpi_table_csrt *csrt;
acpi_status status;
int ret;
status = acpi_get_table(ACPI_SIG_CSRT, 0,
(struct acpi_table_header **)&csrt);
if (ACPI_FAILURE(status)) {
if (status != AE_NOT_FOUND)
dev_warn(&adev->dev, "failed to get the CSRT table\n");
return;
}
grp = (struct acpi_csrt_group *)(csrt + 1);
end = (struct acpi_csrt_group *)((void *)csrt + csrt->header.length);
while (grp < end) {
ret = acpi_dma_parse_resource_group(grp, adev, adma);
if (ret < 0) {
dev_warn(&adev->dev,
"error in parsing resource group\n");
break;
}
grp = (struct acpi_csrt_group *)((void *)grp + grp->length);
}
acpi_put_table((struct acpi_table_header *)csrt);
}
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
/**
* acpi_dma_controller_register - Register a DMA controller to ACPI DMA helpers
* @dev: struct device of DMA controller
* @acpi_dma_xlate: translation function which converts a dma specifier
* into a dma_chan structure
* @data: pointer to controller specific data to be used by
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
* translation function
*
* Allocated memory should be freed with appropriate acpi_dma_controller_free()
* call.
*
* Return:
* 0 on success or appropriate errno value on error.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
int acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data)
{
struct acpi_device *adev;
struct acpi_dma *adma;
if (!dev || !acpi_dma_xlate)
return -EINVAL;
/* Check if the device was enumerated by ACPI */
adev = ACPI_COMPANION(dev);
if (!adev)
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
return -EINVAL;
adma = kzalloc(sizeof(*adma), GFP_KERNEL);
if (!adma)
return -ENOMEM;
adma->dev = dev;
adma->acpi_dma_xlate = acpi_dma_xlate;
adma->data = data;
acpi_dma_parse_csrt(adev, adma);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
/* Now queue acpi_dma controller structure in list */
mutex_lock(&acpi_dma_lock);
list_add_tail(&adma->dma_controllers, &acpi_dma_list);
mutex_unlock(&acpi_dma_lock);
return 0;
}
EXPORT_SYMBOL_GPL(acpi_dma_controller_register);
/**
* acpi_dma_controller_free - Remove a DMA controller from ACPI DMA helpers list
* @dev: struct device of DMA controller
*
* Memory allocated by acpi_dma_controller_register() is freed here.
*
* Return:
* 0 on success or appropriate errno value on error.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
int acpi_dma_controller_free(struct device *dev)
{
struct acpi_dma *adma;
if (!dev)
return -EINVAL;
mutex_lock(&acpi_dma_lock);
list_for_each_entry(adma, &acpi_dma_list, dma_controllers)
if (adma->dev == dev) {
list_del(&adma->dma_controllers);
mutex_unlock(&acpi_dma_lock);
kfree(adma);
return 0;
}
mutex_unlock(&acpi_dma_lock);
return -ENODEV;
}
EXPORT_SYMBOL_GPL(acpi_dma_controller_free);
static void devm_acpi_dma_release(struct device *dev, void *res)
{
acpi_dma_controller_free(dev);
}
/**
* devm_acpi_dma_controller_register - resource managed acpi_dma_controller_register()
* @dev: device that is registering this DMA controller
* @acpi_dma_xlate: translation function
* @data: pointer to controller specific data
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*
* Managed acpi_dma_controller_register(). DMA controller registered by this
* function are automatically freed on driver detach. See
* acpi_dma_controller_register() for more information.
*
* Return:
* 0 on success or appropriate errno value on error.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
int devm_acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data)
{
void *res;
int ret;
res = devres_alloc(devm_acpi_dma_release, 0, GFP_KERNEL);
if (!res)
return -ENOMEM;
ret = acpi_dma_controller_register(dev, acpi_dma_xlate, data);
if (ret) {
devres_free(res);
return ret;
}
devres_add(dev, res);
return 0;
}
EXPORT_SYMBOL_GPL(devm_acpi_dma_controller_register);
/**
* devm_acpi_dma_controller_free - resource managed acpi_dma_controller_free()
* @dev: device that is unregistering as DMA controller
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*
* Unregister a DMA controller registered with
* devm_acpi_dma_controller_register(). Normally this function will not need to
* be called and the resource management code will ensure that the resource is
* freed.
*/
void devm_acpi_dma_controller_free(struct device *dev)
{
WARN_ON(devres_release(dev, devm_acpi_dma_release, NULL, NULL));
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
}
EXPORT_SYMBOL_GPL(devm_acpi_dma_controller_free);
/**
* acpi_dma_update_dma_spec - prepare dma specifier to pass to translation function
* @adma: struct acpi_dma of DMA controller
* @dma_spec: dma specifier to update
*
* Accordingly to ACPI 5.0 Specification Table 6-170 "Fixed DMA Resource
* Descriptor":
* DMA Request Line bits is a platform-relative number uniquely
* identifying the request line assigned. Request line-to-Controller
* mapping is done in a controller-specific OS driver.
* That's why we can safely adjust slave_id when the appropriate controller is
* found.
*
* Return:
* 0, if no information is avaiable, -1 on mismatch, and 1 otherwise.
*/
static int acpi_dma_update_dma_spec(struct acpi_dma *adma,
struct acpi_dma_spec *dma_spec)
{
/* Set link to the DMA controller device */
dma_spec->dev = adma->dev;
/* Check if the request line range is available */
if (adma->base_request_line == 0 && adma->end_request_line == 0)
return 0;
/* Check if slave_id falls to the range */
if (dma_spec->slave_id < adma->base_request_line ||
dma_spec->slave_id > adma->end_request_line)
return -1;
/*
* Here we adjust slave_id. It should be a relative number to the base
* request line.
*/
dma_spec->slave_id -= adma->base_request_line;
return 1;
}
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
struct acpi_dma_parser_data {
struct acpi_dma_spec dma_spec;
size_t index;
size_t n;
};
/**
* acpi_dma_parse_fixed_dma - Parse FixedDMA ACPI resources to a DMA specifier
* @res: struct acpi_resource to get FixedDMA resources from
* @data: pointer to a helper struct acpi_dma_parser_data
*/
static int acpi_dma_parse_fixed_dma(struct acpi_resource *res, void *data)
{
struct acpi_dma_parser_data *pdata = data;
if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) {
struct acpi_resource_fixed_dma *dma = &res->data.fixed_dma;
if (pdata->n++ == pdata->index) {
pdata->dma_spec.chan_id = dma->channels;
pdata->dma_spec.slave_id = dma->request_lines;
}
}
/* Tell the ACPI core to skip this resource */
return 1;
}
/**
* acpi_dma_request_slave_chan_by_index - Get the DMA slave channel
* @dev: struct device to get DMA request from
* @index: index of FixedDMA descriptor for @dev
*
* Return:
* Pointer to appropriate dma channel on success or an error pointer.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
struct dma_chan *acpi_dma_request_slave_chan_by_index(struct device *dev,
size_t index)
{
struct acpi_dma_parser_data pdata;
struct acpi_dma_spec *dma_spec = &pdata.dma_spec;
struct acpi_device *adev = ACPI_COMPANION(dev);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
struct list_head resource_list;
struct acpi_dma *adma;
struct dma_chan *chan = NULL;
int found;
int ret;
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
memset(&pdata, 0, sizeof(pdata));
pdata.index = index;
/* Initial values for the request line and channel */
dma_spec->chan_id = -1;
dma_spec->slave_id = -1;
INIT_LIST_HEAD(&resource_list);
ret = acpi_dev_get_resources(adev, &resource_list,
acpi_dma_parse_fixed_dma, &pdata);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
acpi_dev_free_resource_list(&resource_list);
if (ret < 0)
return ERR_PTR(ret);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
if (dma_spec->slave_id < 0 || dma_spec->chan_id < 0)
return ERR_PTR(-ENODEV);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
mutex_lock(&acpi_dma_lock);
list_for_each_entry(adma, &acpi_dma_list, dma_controllers) {
/*
* We are not going to call translation function if slave_id
* doesn't fall to the request range.
*/
found = acpi_dma_update_dma_spec(adma, dma_spec);
if (found < 0)
continue;
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
chan = adma->acpi_dma_xlate(dma_spec, adma);
/*
* Try to get a channel only from the DMA controller that
* matches the slave_id. See acpi_dma_update_dma_spec()
* description for the details.
*/
if (found > 0 || chan)
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
break;
}
mutex_unlock(&acpi_dma_lock);
return chan ? chan : ERR_PTR(-EPROBE_DEFER);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
}
EXPORT_SYMBOL_GPL(acpi_dma_request_slave_chan_by_index);
/**
* acpi_dma_request_slave_chan_by_name - Get the DMA slave channel
* @dev: struct device to get DMA request from
* @name: represents corresponding FixedDMA descriptor for @dev
*
* In order to support both Device Tree and ACPI in a single driver we
* translate the names "tx" and "rx" here based on the most common case where
* the first FixedDMA descriptor is TX and second is RX.
*
* If the device has "dma-names" property the FixedDMA descriptor indices
* are retrieved based on those. Otherwise the function falls back using
* hardcoded indices.
*
* Return:
* Pointer to appropriate dma channel on success or an error pointer.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev,
const char *name)
{
int index;
index = device_property_match_string(dev, "dma-names", name);
if (index < 0) {
if (!strcmp(name, "tx"))
index = 0;
else if (!strcmp(name, "rx"))
index = 1;
else
return ERR_PTR(-ENODEV);
}
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
dev_dbg(dev, "Looking for DMA channel \"%s\" at index %d...\n", name, index);
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
return acpi_dma_request_slave_chan_by_index(dev, index);
}
EXPORT_SYMBOL_GPL(acpi_dma_request_slave_chan_by_name);
/**
* acpi_dma_simple_xlate - Simple ACPI DMA engine translation helper
* @dma_spec: pointer to ACPI DMA specifier
* @adma: pointer to ACPI DMA controller data
*
* A simple translation function for ACPI based devices. Passes &struct
* dma_spec to the DMA controller driver provided filter function.
*
* Return:
* Pointer to the channel if found or %NULL otherwise.
dma: acpi-dma: introduce ACPI DMA helpers There is a new generic API to get a DMA channel for a slave device (commit 9a6cecc8 "dmaengine: add helper function to request a slave DMA channel"). In similar fashion to the DT case (commit aa3da644 "of: Add generic device tree DMA helpers") we introduce helpers to the DMAC drivers which are enumerated by ACPI. The proposed extension provides the following API calls: acpi_dma_controller_register(), devm_acpi_dma_controller_register() acpi_dma_controller_free(), devm_acpi_dma_controller_free() acpi_dma_simple_xlate() acpi_dma_request_slave_chan_by_index() acpi_dma_request_slave_chan_by_name() The first two should be used, for example, at probe() and remove() of the corresponding DMAC driver. At the register stage the DMAC driver supplies a custom xlate() function to translate a struct dma_spec into struct dma_chan. Accordingly to the ACPI Fixed DMA resource specification the only two pieces of information the slave device has are the channel id and the request line (slave id). Those two are represented by struct dma_spec. The acpi_dma_request_slave_chan_by_index() provides access to the specifix FixedDMA resource by its index. Whereas dma_request_slave_channel() takes a string parameter to identify the DMA resources required by the slave device. To make a slave device driver work with both DeviceTree and ACPI enumeration a simple convention is established: "tx" corresponds to the index 0 and "rx" to the index 1. In case of robust configuration the slave device driver unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly. Additionally the patch provides "managed" version of the register/free pair i.e. devm_acpi_dma_controller_register() and devm_acpi_dma_controller_free(). Usually, the driver uses only devm_acpi_dma_controller_register(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-09 11:05:43 +00:00
*/
struct dma_chan *acpi_dma_simple_xlate(struct acpi_dma_spec *dma_spec,
struct acpi_dma *adma)
{
struct acpi_dma_filter_info *info = adma->data;
if (!info || !info->filter_fn)
return NULL;
return dma_request_channel(info->dma_cap, info->filter_fn, dma_spec);
}
EXPORT_SYMBOL_GPL(acpi_dma_simple_xlate);