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 22static 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, 37 (void *)(uintptr_t)id); 38 if (chan) 39 to_shdma_chan(chan)->hw_req = id; 40 41 return chan; 42} 43 44static int shdma_of_probe(struct platform_device *pdev) 45{ 46 const struct of_dev_auxdata *lookup = dev_get_platdata(&pdev->dev); 47 int ret; 48 49 ret = of_dma_controller_register(pdev->dev.of_node, 50 shdma_of_xlate, pdev); 51 if (ret < 0) 52 return ret; 53 54 ret = of_platform_populate(pdev->dev.of_node, NULL, lookup, &pdev->dev); 55 if (ret < 0) 56 of_dma_controller_free(pdev->dev.of_node); 57 58 return ret; 59} 60 61static const struct of_device_id shdma_of_match[] = { 62 { .compatible = "renesas,shdma-mux", }, 63 { } 64}; 65MODULE_DEVICE_TABLE(of, sh_dmae_of_match); 66 67static struct platform_driver shdma_of = { 68 .driver = { 69 .name = "shdma-of", 70 .of_match_table = shdma_of_match, 71 }, 72 .probe = shdma_of_probe, 73}; 74 75module_platform_driver(shdma_of); 76 77MODULE_LICENSE("GPL v2"); 78MODULE_DESCRIPTION("SH-DMA driver DT glue"); 79MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); 80