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/pm_runtime.h>
19 #include <linux/platform_device.h>
20 #include <linux/dmaengine.h>
21 #include <linux/dma-mapping.h>
23 #include <linux/of_dma.h>
24 #include <linux/acpi.h>
25 #include <linux/acpi_dma.h>
29 static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
32 struct dw_dma *dw = ofdma->of_dma_data;
33 struct dw_dma_slave slave = {
34 .dma_dev = dw->dma.dev,
38 if (dma_spec->args_count != 3)
41 slave.src_id = dma_spec->args[0];
42 slave.dst_id = dma_spec->args[0];
43 slave.src_master = dma_spec->args[1];
44 slave.dst_master = dma_spec->args[2];
46 if (WARN_ON(slave.src_id >= DW_DMA_MAX_NR_REQUESTS ||
47 slave.dst_id >= DW_DMA_MAX_NR_REQUESTS ||
48 slave.src_master >= dw->nr_masters ||
49 slave.dst_master >= dw->nr_masters))
53 dma_cap_set(DMA_SLAVE, cap);
55 /* TODO: there should be a simpler way to do this */
56 return dma_request_channel(cap, dw_dma_filter, &slave);
60 static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
62 struct acpi_dma_spec *dma_spec = param;
63 struct dw_dma_slave slave = {
64 .dma_dev = dma_spec->dev,
65 .src_id = dma_spec->slave_id,
66 .dst_id = dma_spec->slave_id,
71 return dw_dma_filter(chan, &slave);
74 static void dw_dma_acpi_controller_register(struct dw_dma *dw)
76 struct device *dev = dw->dma.dev;
77 struct acpi_dma_filter_info *info;
80 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
84 dma_cap_zero(info->dma_cap);
85 dma_cap_set(DMA_SLAVE, info->dma_cap);
86 info->filter_fn = dw_dma_acpi_filter;
88 ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
91 dev_err(dev, "could not register acpi_dma_controller\n");
93 #else /* !CONFIG_ACPI */
94 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
95 #endif /* !CONFIG_ACPI */
98 static struct dw_dma_platform_data *
99 dw_dma_parse_dt(struct platform_device *pdev)
101 struct device_node *np = pdev->dev.of_node;
102 struct dw_dma_platform_data *pdata;
106 dev_err(&pdev->dev, "Missing DT data\n");
110 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
114 if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
117 if (of_property_read_bool(np, "is_private"))
118 pdata->is_private = true;
120 if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
121 pdata->chan_allocation_order = (unsigned char)tmp;
123 if (!of_property_read_u32(np, "chan_priority", &tmp))
124 pdata->chan_priority = tmp;
126 if (!of_property_read_u32(np, "block_size", &tmp))
127 pdata->block_size = tmp;
129 if (!of_property_read_u32(np, "dma-masters", &tmp)) {
133 pdata->nr_masters = tmp;
136 if (!of_property_read_u32_array(np, "data_width", arr,
138 for (tmp = 0; tmp < pdata->nr_masters; tmp++)
139 pdata->data_width[tmp] = arr[tmp];
144 static inline struct dw_dma_platform_data *
145 dw_dma_parse_dt(struct platform_device *pdev)
151 static int dw_probe(struct platform_device *pdev)
153 struct dw_dma_chip *chip;
154 struct device *dev = &pdev->dev;
155 struct resource *mem;
156 struct dw_dma_platform_data *pdata;
159 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
163 chip->irq = platform_get_irq(pdev, 0);
167 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
168 chip->regs = devm_ioremap_resource(dev, mem);
169 if (IS_ERR(chip->regs))
170 return PTR_ERR(chip->regs);
172 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
176 pdata = dev_get_platdata(dev);
178 pdata = dw_dma_parse_dt(pdev);
182 chip->clk = devm_clk_get(chip->dev, "hclk");
183 if (IS_ERR(chip->clk))
184 return PTR_ERR(chip->clk);
185 err = clk_prepare_enable(chip->clk);
189 pm_runtime_enable(&pdev->dev);
191 err = dw_dma_probe(chip, pdata);
193 goto err_dw_dma_probe;
195 platform_set_drvdata(pdev, chip);
197 if (pdev->dev.of_node) {
198 err = of_dma_controller_register(pdev->dev.of_node,
199 dw_dma_of_xlate, chip->dw);
202 "could not register of_dma_controller\n");
205 if (ACPI_HANDLE(&pdev->dev))
206 dw_dma_acpi_controller_register(chip->dw);
211 pm_runtime_disable(&pdev->dev);
212 clk_disable_unprepare(chip->clk);
216 static int dw_remove(struct platform_device *pdev)
218 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
220 if (pdev->dev.of_node)
221 of_dma_controller_free(pdev->dev.of_node);
224 pm_runtime_disable(&pdev->dev);
225 clk_disable_unprepare(chip->clk);
230 static void dw_shutdown(struct platform_device *pdev)
232 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
234 dw_dma_disable(chip);
235 clk_disable_unprepare(chip->clk);
239 static const struct of_device_id dw_dma_of_id_table[] = {
240 { .compatible = "snps,dma-spear1340" },
243 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
247 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
251 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
254 #ifdef CONFIG_PM_SLEEP
256 static int dw_suspend_late(struct device *dev)
258 struct platform_device *pdev = to_platform_device(dev);
259 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
261 dw_dma_disable(chip);
262 clk_disable_unprepare(chip->clk);
267 static int dw_resume_early(struct device *dev)
269 struct platform_device *pdev = to_platform_device(dev);
270 struct dw_dma_chip *chip = platform_get_drvdata(pdev);
272 clk_prepare_enable(chip->clk);
273 return dw_dma_enable(chip);
276 #endif /* CONFIG_PM_SLEEP */
278 static const struct dev_pm_ops dw_dev_pm_ops = {
279 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
282 static struct platform_driver dw_driver = {
285 .shutdown = dw_shutdown,
288 .pm = &dw_dev_pm_ops,
289 .of_match_table = of_match_ptr(dw_dma_of_id_table),
290 .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
294 static int __init dw_init(void)
296 return platform_driver_register(&dw_driver);
298 subsys_initcall(dw_init);
300 static void __exit dw_exit(void)
302 platform_driver_unregister(&dw_driver);
304 module_exit(dw_exit);
306 MODULE_LICENSE("GPL v2");
307 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");