1 /* 2 * Hisilicon Hi6220 reset controller driver 3 * 4 * Copyright (c) 2015 Hisilicon Limited. 5 * 6 * Author: Feng Chen <puck.chen@hisilicon.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/io.h> 14 #include <linux/init.h> 15 #include <linux/module.h> 16 #include <linux/bitops.h> 17 #include <linux/of.h> 18 #include <linux/reset-controller.h> 19 #include <linux/reset.h> 20 #include <linux/platform_device.h> 21 22 #define ASSERT_OFFSET 0x300 23 #define DEASSERT_OFFSET 0x304 24 #define MAX_INDEX 0x509 25 26 #define to_reset_data(x) container_of(x, struct hi6220_reset_data, rc_dev) 27 28 struct hi6220_reset_data { 29 void __iomem *assert_base; 30 void __iomem *deassert_base; 31 struct reset_controller_dev rc_dev; 32 }; 33 34 static int hi6220_reset_assert(struct reset_controller_dev *rc_dev, 35 unsigned long idx) 36 { 37 struct hi6220_reset_data *data = to_reset_data(rc_dev); 38 39 int bank = idx >> 8; 40 int offset = idx & 0xff; 41 42 writel(BIT(offset), data->assert_base + (bank * 0x10)); 43 44 return 0; 45 } 46 47 static int hi6220_reset_deassert(struct reset_controller_dev *rc_dev, 48 unsigned long idx) 49 { 50 struct hi6220_reset_data *data = to_reset_data(rc_dev); 51 52 int bank = idx >> 8; 53 int offset = idx & 0xff; 54 55 writel(BIT(offset), data->deassert_base + (bank * 0x10)); 56 57 return 0; 58 } 59 60 static const struct reset_control_ops hi6220_reset_ops = { 61 .assert = hi6220_reset_assert, 62 .deassert = hi6220_reset_deassert, 63 }; 64 65 static int hi6220_reset_probe(struct platform_device *pdev) 66 { 67 struct hi6220_reset_data *data; 68 struct resource *res; 69 void __iomem *src_base; 70 71 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); 72 if (!data) 73 return -ENOMEM; 74 75 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 76 src_base = devm_ioremap_resource(&pdev->dev, res); 77 if (IS_ERR(src_base)) 78 return PTR_ERR(src_base); 79 80 data->assert_base = src_base + ASSERT_OFFSET; 81 data->deassert_base = src_base + DEASSERT_OFFSET; 82 data->rc_dev.nr_resets = MAX_INDEX; 83 data->rc_dev.ops = &hi6220_reset_ops; 84 data->rc_dev.of_node = pdev->dev.of_node; 85 86 return reset_controller_register(&data->rc_dev); 87 } 88 89 static const struct of_device_id hi6220_reset_match[] = { 90 { .compatible = "hisilicon,hi6220-sysctrl" }, 91 { }, 92 }; 93 94 static struct platform_driver hi6220_reset_driver = { 95 .probe = hi6220_reset_probe, 96 .driver = { 97 .name = "reset-hi6220", 98 .of_match_table = hi6220_reset_match, 99 }, 100 }; 101 102 static int __init hi6220_reset_init(void) 103 { 104 return platform_driver_register(&hi6220_reset_driver); 105 } 106 107 postcore_initcall(hi6220_reset_init); 108