| Guennadi Liakhovetski | 67eacc1 | 2013-06-18 18:16:57 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * SHDMA Device Tree glue |
| 3 | * |
| 4 | * Copyright (C) 2013 Renesas Electronics Inc. |
| 5 | * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> |
| 6 | * |
| 7 | * This is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of version 2 of the GNU General Public License as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/dmaengine.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/of.h> |
| 15 | #include <linux/of_dma.h> |
| 16 | #include <linux/of_platform.h> |
| 17 | #include <linux/platform_device.h> |
| 18 | #include <linux/shdma-base.h> |
| 19 | |
| 20 | #define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan) |
| 21 | |
| 22 | static struct dma_chan *shdma_of_xlate(struct of_phandle_args *dma_spec, |
| 23 | struct of_dma *ofdma) |
| 24 | { |
| 25 | u32 id = dma_spec->args[0]; |
| 26 | dma_cap_mask_t mask; |
| 27 | struct dma_chan *chan; |
| 28 | |
| 29 | if (dma_spec->args_count != 1) |
| 30 | return NULL; |
| 31 | |
| 32 | dma_cap_zero(mask); |
| 33 | /* Only slave DMA channels can be allocated via DT */ |
| 34 | dma_cap_set(DMA_SLAVE, mask); |
| 35 | |
| 36 | chan = dma_request_channel(mask, shdma_chan_filter, (void *)id); |
| 37 | if (chan) |
| 38 | to_shdma_chan(chan)->hw_req = id; |
| 39 | |
| 40 | return chan; |
| 41 | } |
| 42 | |
| 43 | static int shdma_of_probe(struct platform_device *pdev) |
| 44 | { |
| 45 | const struct of_dev_auxdata *lookup = pdev->dev.platform_data; |
| 46 | int ret; |
| 47 | |
| 48 | if (!lookup) |
| 49 | return -EINVAL; |
| 50 | |
| 51 | ret = of_dma_controller_register(pdev->dev.of_node, |
| 52 | shdma_of_xlate, pdev); |
| 53 | if (ret < 0) |
| 54 | return ret; |
| 55 | |
| 56 | ret = of_platform_populate(pdev->dev.of_node, NULL, lookup, &pdev->dev); |
| 57 | if (ret < 0) |
| 58 | of_dma_controller_free(pdev->dev.of_node); |
| 59 | |
| 60 | return ret; |
| 61 | } |
| 62 | |
| 63 | static const struct of_device_id shdma_of_match[] = { |
| 64 | { .compatible = "renesas,shdma-mux", }, |
| 65 | { } |
| 66 | }; |
| 67 | MODULE_DEVICE_TABLE(of, sh_dmae_of_match); |
| 68 | |
| 69 | static struct platform_driver shdma_of = { |
| 70 | .driver = { |
| 71 | .owner = THIS_MODULE, |
| 72 | .name = "shdma-of", |
| 73 | .of_match_table = shdma_of_match, |
| 74 | }, |
| 75 | .probe = shdma_of_probe, |
| 76 | }; |
| 77 | |
| 78 | module_platform_driver(shdma_of); |
| 79 | |
| 80 | MODULE_LICENSE("GPL v2"); |
| 81 | MODULE_DESCRIPTION("SH-DMA driver DT glue"); |
| 82 | MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); |