projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 60aae8da SG |
1 | /** |
| 2 | * Freescale ALSA SoC Machine driver utility | |
| 3 | * | |
| 4 | * Author: Timur Tabi <timur@freescale.com> | |
| 5 | * | |
| 6 | * Copyright 2010 Freescale Semiconductor, Inc. | |
| 7 | * | |
| 8 | * This file is licensed under the terms of the GNU General Public License | |
| 9 | * version 2. This program is licensed "as is" without any warranty of any | |
| 10 | * kind, whether express or implied. | |
| 11 | */ | |
| 12 | ||
| 13 | #include <linux/module.h> | |
| 14 | #include <linux/of_address.h> | |
| 60aae8da SG |
15 | #include <sound/soc.h> |
| 16 | ||
| 17 | #include "fsl_utils.h" | |
| 18 | ||
| 60aae8da SG |
19 | /** |
| 20 | * fsl_asoc_get_dma_channel - determine the dma channel for a SSI node | |
| 21 | * | |
| 22 | * @ssi_np: pointer to the SSI device tree node | |
| 23 | * @name: name of the phandle pointing to the dma channel | |
| 24 | * @dai: ASoC DAI link pointer to be filled with platform_name | |
| 25 | * @dma_channel_id: dma channel id to be returned | |
| 26 | * @dma_id: dma id to be returned | |
| 27 | * | |
| 28 | * This function determines the dma and channel id for given SSI node. It | |
| 29 | * also discovers the platform_name for the ASoC DAI link. | |
| 30 | */ | |
| 31 | int fsl_asoc_get_dma_channel(struct device_node *ssi_np, | |
| 32 | const char *name, | |
| 33 | struct snd_soc_dai_link *dai, | |
| 34 | unsigned int *dma_channel_id, | |
| 35 | unsigned int *dma_id) | |
| 36 | { | |
| 37 | struct resource res; | |
| 38 | struct device_node *dma_channel_np, *dma_np; | |
| 39 | const u32 *iprop; | |
| 40 | int ret; | |
| 41 | ||
| 42 | dma_channel_np = of_parse_phandle(ssi_np, name, 0); | |
| 43 | if (!dma_channel_np) | |
| 44 | return -EINVAL; | |
| 45 | ||
| 46 | if (!of_device_is_compatible(dma_channel_np, "fsl,ssi-dma-channel")) { | |
| 47 | of_node_put(dma_channel_np); | |
| 48 | return -EINVAL; | |
| 49 | } | |
| 50 | ||
| 51 | /* Determine the dev_name for the device_node. This code mimics the | |
| 52 | * behavior of of_device_make_bus_id(). We need this because ASoC uses | |
| 53 | * the dev_name() of the device to match the platform (DMA) device with | |
| 54 | * the CPU (SSI) device. It's all ugly and hackish, but it works (for | |
| 55 | * now). | |
| 56 | * | |
| 57 | * dai->platform name should already point to an allocated buffer. | |
| 58 | */ | |
| 59 | ret = of_address_to_resource(dma_channel_np, 0, &res); | |
| 60 | if (ret) { | |
| 61 | of_node_put(dma_channel_np); | |
| 62 | return ret; | |
| 63 | } | |
| 64 | snprintf((char *)dai->platform_name, DAI_NAME_SIZE, "%llx.%s", | |
| 65 | (unsigned long long) res.start, dma_channel_np->name); | |
| 66 | ||
| 67 | iprop = of_get_property(dma_channel_np, "cell-index", NULL); | |
| 68 | if (!iprop) { | |
| 69 | of_node_put(dma_channel_np); | |
| 70 | return -EINVAL; | |
| 71 | } | |
| 72 | *dma_channel_id = be32_to_cpup(iprop); | |
| 73 | ||
| 74 | dma_np = of_get_parent(dma_channel_np); | |
| 75 | iprop = of_get_property(dma_np, "cell-index", NULL); | |
| 76 | if (!iprop) { | |
| 77 | of_node_put(dma_np); | |
| 78 | return -EINVAL; | |
| 79 | } | |
| 80 | *dma_id = be32_to_cpup(iprop); | |
| 81 | ||
| 82 | of_node_put(dma_np); | |
| 83 | of_node_put(dma_channel_np); | |
| 84 | ||
| 85 | return 0; | |
| 86 | } | |
| 87 | EXPORT_SYMBOL(fsl_asoc_get_dma_channel); | |
| 88 | ||
| 89 | MODULE_AUTHOR("Timur Tabi <timur@freescale.com>"); | |
| 90 | MODULE_DESCRIPTION("Freescale ASoC utility code"); | |
| 91 | MODULE_LICENSE("GPL v2"); |