From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- sound/soc/fsl/fsl_utils.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 sound/soc/fsl/fsl_utils.c (limited to 'sound/soc/fsl/fsl_utils.c') diff --git a/sound/soc/fsl/fsl_utils.c b/sound/soc/fsl/fsl_utils.c new file mode 100644 index 000000000..b9e42b503 --- /dev/null +++ b/sound/soc/fsl/fsl_utils.c @@ -0,0 +1,91 @@ +/** + * Freescale ALSA SoC Machine driver utility + * + * Author: Timur Tabi + * + * Copyright 2010 Freescale Semiconductor, Inc. + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +#include +#include +#include + +#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 u32 *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); + 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 "); +MODULE_DESCRIPTION("Freescale ASoC utility code"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3-54-g00ecf