xref: /openbmc/linux/drivers/dma/dw/platform.c (revision b4a6aaea)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Platform driver for the Synopsys DesignWare DMA Controller
4  *
5  * Copyright (C) 2007-2008 Atmel Corporation
6  * Copyright (C) 2010-2011 ST Microelectronics
7  * Copyright (C) 2013 Intel Corporation
8  *
9  * Some parts of this driver are derived from the original dw_dmac.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/clk.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/platform_device.h>
17 #include <linux/dmaengine.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/of.h>
20 #include <linux/acpi.h>
21 
22 #include "internal.h"
23 
24 #define DRV_NAME	"dw_dmac"
25 
26 static int dw_probe(struct platform_device *pdev)
27 {
28 	const struct dw_dma_chip_pdata *match;
29 	struct dw_dma_chip_pdata *data;
30 	struct dw_dma_chip *chip;
31 	struct device *dev = &pdev->dev;
32 	int err;
33 
34 	match = device_get_match_data(dev);
35 	if (!match)
36 		return -ENODEV;
37 
38 	data = devm_kmemdup(&pdev->dev, match, sizeof(*match), GFP_KERNEL);
39 	if (!data)
40 		return -ENOMEM;
41 
42 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
43 	if (!chip)
44 		return -ENOMEM;
45 
46 	chip->irq = platform_get_irq(pdev, 0);
47 	if (chip->irq < 0)
48 		return chip->irq;
49 
50 	chip->regs = devm_platform_ioremap_resource(pdev, 0);
51 	if (IS_ERR(chip->regs))
52 		return PTR_ERR(chip->regs);
53 
54 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
55 	if (err)
56 		return err;
57 
58 	if (!data->pdata)
59 		data->pdata = dev_get_platdata(dev);
60 	if (!data->pdata)
61 		data->pdata = dw_dma_parse_dt(pdev);
62 
63 	chip->dev = dev;
64 	chip->id = pdev->id;
65 	chip->pdata = data->pdata;
66 
67 	data->chip = chip;
68 
69 	chip->clk = devm_clk_get_optional(chip->dev, "hclk");
70 	if (IS_ERR(chip->clk))
71 		return PTR_ERR(chip->clk);
72 	err = clk_prepare_enable(chip->clk);
73 	if (err)
74 		return err;
75 
76 	pm_runtime_enable(&pdev->dev);
77 
78 	err = data->probe(chip);
79 	if (err)
80 		goto err_dw_dma_probe;
81 
82 	platform_set_drvdata(pdev, data);
83 
84 	dw_dma_of_controller_register(chip->dw);
85 
86 	dw_dma_acpi_controller_register(chip->dw);
87 
88 	return 0;
89 
90 err_dw_dma_probe:
91 	pm_runtime_disable(&pdev->dev);
92 	clk_disable_unprepare(chip->clk);
93 	return err;
94 }
95 
96 static int dw_remove(struct platform_device *pdev)
97 {
98 	struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
99 	struct dw_dma_chip *chip = data->chip;
100 	int ret;
101 
102 	dw_dma_acpi_controller_free(chip->dw);
103 
104 	dw_dma_of_controller_free(chip->dw);
105 
106 	ret = data->remove(chip);
107 	if (ret)
108 		dev_warn(chip->dev, "can't remove device properly: %d\n", ret);
109 
110 	pm_runtime_disable(&pdev->dev);
111 	clk_disable_unprepare(chip->clk);
112 
113 	return 0;
114 }
115 
116 static void dw_shutdown(struct platform_device *pdev)
117 {
118 	struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
119 	struct dw_dma_chip *chip = data->chip;
120 
121 	/*
122 	 * We have to call do_dw_dma_disable() to stop any ongoing transfer. On
123 	 * some platforms we can't do that since DMA device is powered off.
124 	 * Moreover we have no possibility to check if the platform is affected
125 	 * or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
126 	 * unconditionally. On the other hand we can't use
127 	 * pm_runtime_suspended() because runtime PM framework is not fully
128 	 * used by the driver.
129 	 */
130 	pm_runtime_get_sync(chip->dev);
131 	do_dw_dma_disable(chip);
132 	pm_runtime_put_sync_suspend(chip->dev);
133 
134 	clk_disable_unprepare(chip->clk);
135 }
136 
137 #ifdef CONFIG_OF
138 static const struct of_device_id dw_dma_of_id_table[] = {
139 	{ .compatible = "snps,dma-spear1340", .data = &dw_dma_chip_pdata },
140 	{}
141 };
142 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
143 #endif
144 
145 #ifdef CONFIG_ACPI
146 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
147 	{ "INTL9C60", (kernel_ulong_t)&dw_dma_chip_pdata },
148 	{ "80862286", (kernel_ulong_t)&dw_dma_chip_pdata },
149 	{ "808622C0", (kernel_ulong_t)&dw_dma_chip_pdata },
150 
151 	/* Elkhart Lake iDMA 32-bit (PSE DMA) */
152 	{ "80864BB4", (kernel_ulong_t)&xbar_chip_pdata },
153 	{ "80864BB5", (kernel_ulong_t)&xbar_chip_pdata },
154 	{ "80864BB6", (kernel_ulong_t)&xbar_chip_pdata },
155 
156 	{ }
157 };
158 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
159 #endif
160 
161 #ifdef CONFIG_PM_SLEEP
162 
163 static int dw_suspend_late(struct device *dev)
164 {
165 	struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
166 	struct dw_dma_chip *chip = data->chip;
167 
168 	do_dw_dma_disable(chip);
169 	clk_disable_unprepare(chip->clk);
170 
171 	return 0;
172 }
173 
174 static int dw_resume_early(struct device *dev)
175 {
176 	struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
177 	struct dw_dma_chip *chip = data->chip;
178 	int ret;
179 
180 	ret = clk_prepare_enable(chip->clk);
181 	if (ret)
182 		return ret;
183 
184 	return do_dw_dma_enable(chip);
185 }
186 
187 #endif /* CONFIG_PM_SLEEP */
188 
189 static const struct dev_pm_ops dw_dev_pm_ops = {
190 	SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
191 };
192 
193 static struct platform_driver dw_driver = {
194 	.probe		= dw_probe,
195 	.remove		= dw_remove,
196 	.shutdown       = dw_shutdown,
197 	.driver = {
198 		.name	= DRV_NAME,
199 		.pm	= &dw_dev_pm_ops,
200 		.of_match_table = of_match_ptr(dw_dma_of_id_table),
201 		.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
202 	},
203 };
204 
205 static int __init dw_init(void)
206 {
207 	return platform_driver_register(&dw_driver);
208 }
209 subsys_initcall(dw_init);
210 
211 static void __exit dw_exit(void)
212 {
213 	platform_driver_unregister(&dw_driver);
214 }
215 module_exit(dw_exit);
216 
217 MODULE_LICENSE("GPL v2");
218 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
219 MODULE_ALIAS("platform:" DRV_NAME);
220