2 * Platform driver for the Synopsys DesignWare DMA Controller
4 * Copyright (C) 2007-2008 Atmel Corporation
5 * Copyright (C) 2010-2011 ST Microelectronics
6 * Copyright (C) 2013 Intel Corporation
8 * Some parts of this driver are derived from the original dw_dmac.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <linux/clk.h>
18 #include <linux/platform_device.h>
19 #include <linux/dmaengine.h>
20 #include <linux/dma-mapping.h>
22 #include <linux/of_dma.h>
23 #include <linux/acpi.h>
24 #include <linux/acpi_dma.h>
28 static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
31 struct dw_dma *dw = ofdma->of_dma_data;
32 struct dw_dma_slave slave = {
33 .dma_dev = dw->dma.dev,
37 if (dma_spec->args_count != 3)
40 slave.src_id = dma_spec->args[0];
41 slave.dst_id = dma_spec->args[0];
42 slave.src_master = dma_spec->args[1];
43 slave.dst_master = dma_spec->args[2];
45 if (WARN_ON(slave.src_id >= DW_DMA_MAX_NR_REQUESTS ||
46 slave.dst_id >= DW_DMA_MAX_NR_REQUESTS ||
47 slave.src_master >= dw->nr_masters ||
48 slave.dst_master >= dw->nr_masters))
52 dma_cap_set(DMA_SLAVE, cap);
54 /* TODO: there should be a simpler way to do this */
55 return dma_request_channel(cap, dw_dma_filter, &slave);
59 static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
61 struct acpi_dma_spec *dma_spec = param;
62 struct dw_dma_slave slave = {
63 .dma_dev = dma_spec->dev,
64 .src_id = dma_spec->slave_id,
65 .dst_id = dma_spec->slave_id,
70 return dw_dma_filter(chan, &slave);
73 static void dw_dma_acpi_controller_register(struct dw_dma *dw)
75 struct device *dev = dw->dma.dev;
76 struct acpi_dma_filter_info *info;
79 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
83 dma_cap_zero(info->dma_cap);
84 dma_cap_set(DMA_SLAVE, info->dma_cap);
85 info->filter_fn = dw_dma_acpi_filter;
87 ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
90 dev_err(dev, "could not register acpi_dma_controller\n");
92 #else /* !CONFIG_ACPI */
93 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
94 #endif /* !CONFIG_ACPI */
97 static struct dw_dma_platform_data *
98 dw_dma_parse_dt(struct platform_device *pdev)
100 struct device_node *np = pdev->dev.of_node;
101 struct dw_dma_platform_data *pdata;
105 dev_err(&pdev->dev, "Missing DT data\n");
109 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
113 if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
116 if (of_property_read_bool(np, "is_private"))
117 pdata->is_private = true;
119 if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
120 pdata->chan_allocation_order = (unsigned char)tmp;
122 if (!of_property_read_u32(np, "chan_priority", &tmp))
123 pdata->chan_priority = tmp;
125 if (!of_property_read_u32(np, "block_size", &tmp))
126 pdata->block_size = tmp;
128 if (!of_property_read_u32(np, "dma-masters", &tmp)) {
132 pdata->nr_masters = tmp;
135 if (!of_property_read_u32_array(np, "data_width", arr,
137 for (tmp = 0; tmp < pdata->nr_masters; tmp++)
138 pdata->data_width[tmp] = arr[tmp];
143 static inline struct dw_dma_platform_data *
144 dw_dma_parse_dt(struct platform_device *pdev)
150 static int dw_probe(struct platform_device *pdev)
152 struct dw_dma_chip *chip;
153 struct device *dev = &pdev->dev;
154 struct resource *mem;
155 struct dw_dma_platform_data *pdata;
158 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
162 chip->irq = platform_get_irq(pdev, 0);
166 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
167 chip->regs = devm_ioremap_resource(dev, mem);
168 if (IS_ERR(chip->regs))
169 return PTR_ERR(chip->regs);
171 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
175 pdata = dev_get_platdata(dev);
177 pdata = dw_dma_parse_dt(pdev);
181 chip->clk = devm_clk_get(chip->dev, "hclk");
182 if (IS_ERR(chip->clk))
183 return PTR_ERR(chip->clk);
184 err = clk_prepare_enable(chip->clk);
188 err = dw_dma_probe(chip, pdata);
190 goto err_dw_dma_probe;
192 platform_set_drvdata(pdev, chip);
194 if (pdev->dev.of_node) {
195 err = of_dma_controller_register(pdev->dev.of_node,
196 dw_dma_of_xlate, chip->dw);
199 "could not register of_dma_controller\n");
202 if (ACPI_HANDLE(&pdev->dev))
203 dw_dma_acpi_controller_register(chip->dw);
208 clk_disable_unprepare(chip->clk);
212 static int dw_remove(struct platform_device *pdev)
214 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
216 if (pdev->dev.of_node)
217 of_dma_controller_free(pdev->dev.of_node);
220 clk_disable_unprepare(chip->clk);
225 static void dw_shutdown(struct platform_device *pdev)
227 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
229 dw_dma_disable(chip);
230 clk_disable_unprepare(chip->clk);
234 static const struct of_device_id dw_dma_of_id_table[] = {
235 { .compatible = "snps,dma-spear1340" },
238 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
242 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
246 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
249 #ifdef CONFIG_PM_SLEEP
251 static int dw_suspend_late(struct device *dev)
253 struct platform_device *pdev = to_platform_device(dev);
254 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
256 dw_dma_disable(chip);
257 clk_disable_unprepare(chip->clk);
262 static int dw_resume_early(struct device *dev)
264 struct platform_device *pdev = to_platform_device(dev);
265 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
267 clk_prepare_enable(chip->clk);
268 return dw_dma_enable(chip);
271 #endif /* CONFIG_PM_SLEEP */
273 static const struct dev_pm_ops dw_dev_pm_ops = {
274 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
277 static struct platform_driver dw_driver = {
280 .shutdown = dw_shutdown,
283 .pm = &dw_dev_pm_ops,
284 .of_match_table = of_match_ptr(dw_dma_of_id_table),
285 .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
289 static int __init dw_init(void)
291 return platform_driver_register(&dw_driver);
293 subsys_initcall(dw_init);
295 static void __exit dw_exit(void)
297 platform_driver_unregister(&dw_driver);
299 module_exit(dw_exit);
301 MODULE_LICENSE("GPL v2");
302 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");