1 /*
2 * Copyright (C) 2017 Synopsys.
3 *
4 * Synopsys AXS10x reset driver.
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/platform_device.h>
15 #include <linux/reset-controller.h>
16
17 #define to_axs10x_rst(p) container_of((p), struct axs10x_rst, rcdev)
18
19 #define AXS10X_MAX_RESETS 32
20
21 struct axs10x_rst {
22 void __iomem *regs_rst;
23 spinlock_t lock;
24 struct reset_controller_dev rcdev;
25 };
26
axs10x_reset_reset(struct reset_controller_dev * rcdev,unsigned long id)27 static int axs10x_reset_reset(struct reset_controller_dev *rcdev,
28 unsigned long id)
29 {
30 struct axs10x_rst *rst = to_axs10x_rst(rcdev);
31 unsigned long flags;
32
33 spin_lock_irqsave(&rst->lock, flags);
34 writel(BIT(id), rst->regs_rst);
35 spin_unlock_irqrestore(&rst->lock, flags);
36
37 return 0;
38 }
39
40 static const struct reset_control_ops axs10x_reset_ops = {
41 .reset = axs10x_reset_reset,
42 };
43
axs10x_reset_probe(struct platform_device * pdev)44 static int axs10x_reset_probe(struct platform_device *pdev)
45 {
46 struct axs10x_rst *rst;
47
48 rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL);
49 if (!rst)
50 return -ENOMEM;
51
52 rst->regs_rst = devm_platform_ioremap_resource(pdev, 0);
53 if (IS_ERR(rst->regs_rst))
54 return PTR_ERR(rst->regs_rst);
55
56 spin_lock_init(&rst->lock);
57
58 rst->rcdev.owner = THIS_MODULE;
59 rst->rcdev.ops = &axs10x_reset_ops;
60 rst->rcdev.of_node = pdev->dev.of_node;
61 rst->rcdev.nr_resets = AXS10X_MAX_RESETS;
62
63 return devm_reset_controller_register(&pdev->dev, &rst->rcdev);
64 }
65
66 static const struct of_device_id axs10x_reset_dt_match[] = {
67 { .compatible = "snps,axs10x-reset" },
68 { },
69 };
70
71 static struct platform_driver axs10x_reset_driver = {
72 .probe = axs10x_reset_probe,
73 .driver = {
74 .name = "axs10x-reset",
75 .of_match_table = axs10x_reset_dt_match,
76 },
77 };
78 builtin_platform_driver(axs10x_reset_driver);
79
80 MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
81 MODULE_DESCRIPTION("Synopsys AXS10x reset driver");
82 MODULE_LICENSE("GPL v2");
83
