89 lines
2.4 KiB
C
89 lines
2.4 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
//
|
||
|
// Freescale ALSA SoC Machine driver utility
|
||
|
//
|
||
|
// Author: Timur Tabi <timur@freescale.com>
|
||
|
//
|
||
|
// Copyright 2010 Freescale Semiconductor, Inc.
|
||
|
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/of_address.h>
|
||
|
#include <sound/soc.h>
|
||
|
|
||
|
#include "fsl_utils.h"
|
||
|
|
||
|
/**
|
||
|
* fsl_asoc_get_dma_channel - determine the dma channel for a SSI node
|
||
|
*
|
||
|
* @ssi_np: pointer to the SSI device tree node
|
||
|
* @name: name of the phandle pointing to the dma channel
|
||
|
* @dai: ASoC DAI link pointer to be filled with platform_name
|
||
|
* @dma_channel_id: dma channel id to be returned
|
||
|
* @dma_id: dma id to be returned
|
||
|
*
|
||
|
* This function determines the dma and channel id for given SSI node. It
|
||
|
* also discovers the platform_name for the ASoC DAI link.
|
||
|
*/
|
||
|
int fsl_asoc_get_dma_channel(struct device_node *ssi_np,
|
||
|
const char *name,
|
||
|
struct snd_soc_dai_link *dai,
|
||
|
unsigned int *dma_channel_id,
|
||
|
unsigned int *dma_id)
|
||
|
{
|
||
|
struct resource res;
|
||
|
struct device_node *dma_channel_np, *dma_np;
|
||
|
const __be32 *iprop;
|
||
|
int ret;
|
||
|
|
||
|
dma_channel_np = of_parse_phandle(ssi_np, name, 0);
|
||
|
if (!dma_channel_np)
|
||
|
return -EINVAL;
|
||
|
|
||
|
if (!of_device_is_compatible(dma_channel_np, "fsl,ssi-dma-channel")) {
|
||
|
of_node_put(dma_channel_np);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* Determine the dev_name for the device_node. This code mimics the
|
||
|
* behavior of of_device_make_bus_id(). We need this because ASoC uses
|
||
|
* the dev_name() of the device to match the platform (DMA) device with
|
||
|
* the CPU (SSI) device. It's all ugly and hackish, but it works (for
|
||
|
* now).
|
||
|
*
|
||
|
* dai->platform name should already point to an allocated buffer.
|
||
|
*/
|
||
|
ret = of_address_to_resource(dma_channel_np, 0, &res);
|
||
|
if (ret) {
|
||
|
of_node_put(dma_channel_np);
|
||
|
return ret;
|
||
|
}
|
||
|
snprintf((char *)dai->platform_name, DAI_NAME_SIZE, "%llx.%s",
|
||
|
(unsigned long long) res.start, dma_channel_np->name);
|
||
|
|
||
|
iprop = of_get_property(dma_channel_np, "cell-index", NULL);
|
||
|
if (!iprop) {
|
||
|
of_node_put(dma_channel_np);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
*dma_channel_id = be32_to_cpup(iprop);
|
||
|
|
||
|
dma_np = of_get_parent(dma_channel_np);
|
||
|
iprop = of_get_property(dma_np, "cell-index", NULL);
|
||
|
if (!iprop) {
|
||
|
of_node_put(dma_np);
|
||
|
of_node_put(dma_channel_np);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
*dma_id = be32_to_cpup(iprop);
|
||
|
|
||
|
of_node_put(dma_np);
|
||
|
of_node_put(dma_channel_np);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
EXPORT_SYMBOL(fsl_asoc_get_dma_channel);
|
||
|
|
||
|
MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
|
||
|
MODULE_DESCRIPTION("Freescale ASoC utility code");
|
||
|
MODULE_LICENSE("GPL v2");
|