treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / dma / dw / platform.c
blob0585d749d935c5377fde18fef387ff6838efca81
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Platform driver for the Synopsys DesignWare DMA Controller
5 * Copyright (C) 2007-2008 Atmel Corporation
6 * Copyright (C) 2010-2011 ST Microelectronics
7 * Copyright (C) 2013 Intel Corporation
9 * Some parts of this driver are derived from the original dw_dmac.
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>
22 #include "internal.h"
24 #define DRV_NAME "dw_dmac"
26 static int dw_probe(struct platform_device *pdev)
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;
34 match = device_get_match_data(dev);
35 if (!match)
36 return -ENODEV;
38 data = devm_kmemdup(&pdev->dev, match, sizeof(*match), GFP_KERNEL);
39 if (!data)
40 return -ENOMEM;
42 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
43 if (!chip)
44 return -ENOMEM;
46 chip->irq = platform_get_irq(pdev, 0);
47 if (chip->irq < 0)
48 return chip->irq;
50 chip->regs = devm_platform_ioremap_resource(pdev, 0);
51 if (IS_ERR(chip->regs))
52 return PTR_ERR(chip->regs);
54 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
55 if (err)
56 return err;
58 if (!data->pdata)
59 data->pdata = dev_get_platdata(dev);
60 if (!data->pdata)
61 data->pdata = dw_dma_parse_dt(pdev);
63 chip->dev = dev;
64 chip->id = pdev->id;
65 chip->pdata = data->pdata;
67 data->chip = chip;
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;
76 pm_runtime_enable(&pdev->dev);
78 err = data->probe(chip);
79 if (err)
80 goto err_dw_dma_probe;
82 platform_set_drvdata(pdev, data);
84 dw_dma_of_controller_register(chip->dw);
86 dw_dma_acpi_controller_register(chip->dw);
88 return 0;
90 err_dw_dma_probe:
91 pm_runtime_disable(&pdev->dev);
92 clk_disable_unprepare(chip->clk);
93 return err;
96 static int dw_remove(struct platform_device *pdev)
98 struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
99 struct dw_dma_chip *chip = data->chip;
100 int ret;
102 dw_dma_acpi_controller_free(chip->dw);
104 dw_dma_of_controller_free(chip->dw);
106 ret = data->remove(chip);
107 if (ret)
108 dev_warn(chip->dev, "can't remove device properly: %d\n", ret);
110 pm_runtime_disable(&pdev->dev);
111 clk_disable_unprepare(chip->clk);
113 return 0;
116 static void dw_shutdown(struct platform_device *pdev)
118 struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
119 struct dw_dma_chip *chip = data->chip;
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.
130 pm_runtime_get_sync(chip->dev);
131 do_dw_dma_disable(chip);
132 pm_runtime_put_sync_suspend(chip->dev);
134 clk_disable_unprepare(chip->clk);
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 },
142 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
143 #endif
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 },
151 /* Elkhart Lake iDMA 32-bit (PSE DMA) */
152 { "80864BB4", (kernel_ulong_t)&idma32_chip_pdata },
153 { "80864BB5", (kernel_ulong_t)&idma32_chip_pdata },
154 { "80864BB6", (kernel_ulong_t)&idma32_chip_pdata },
158 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
159 #endif
161 #ifdef CONFIG_PM_SLEEP
163 static int dw_suspend_late(struct device *dev)
165 struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
166 struct dw_dma_chip *chip = data->chip;
168 do_dw_dma_disable(chip);
169 clk_disable_unprepare(chip->clk);
171 return 0;
174 static int dw_resume_early(struct device *dev)
176 struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
177 struct dw_dma_chip *chip = data->chip;
178 int ret;
180 ret = clk_prepare_enable(chip->clk);
181 if (ret)
182 return ret;
184 return do_dw_dma_enable(chip);
187 #endif /* CONFIG_PM_SLEEP */
189 static const struct dev_pm_ops dw_dev_pm_ops = {
190 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
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),
205 static int __init dw_init(void)
207 return platform_driver_register(&dw_driver);
209 subsys_initcall(dw_init);
211 static void __exit dw_exit(void)
213 platform_driver_unregister(&dw_driver);
215 module_exit(dw_exit);
217 MODULE_LICENSE("GPL v2");
218 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
219 MODULE_ALIAS("platform:" DRV_NAME);