projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| b38386f4 BX |
1 | /* |
| 2 | * ZTE's zx2967 family reset controller driver | |
| 3 | * | |
| 4 | * Copyright (C) 2017 ZTE Ltd. | |
| 5 | * | |
| 6 | * Author: Baoyou Xie <baoyou.xie@linaro.org> | |
| 7 | * | |
| 8 | * License terms: GNU General Public License (GPL) version 2 | |
| 9 | */ | |
| 10 | ||
| b38386f4 BX |
11 | #include <linux/of_address.h> |
| 12 | #include <linux/platform_device.h> | |
| 13 | #include <linux/reset-controller.h> | |
| 14 | ||
| 15 | struct zx2967_reset { | |
| 16 | void __iomem *reg_base; | |
| 17 | spinlock_t lock; | |
| 18 | struct reset_controller_dev rcdev; | |
| 19 | }; | |
| 20 | ||
| 21 | static int zx2967_reset_act(struct reset_controller_dev *rcdev, | |
| 22 | unsigned long id, bool assert) | |
| 23 | { | |
| 24 | struct zx2967_reset *reset = NULL; | |
| 25 | int bank = id / 32; | |
| 26 | int offset = id % 32; | |
| 27 | u32 reg; | |
| 28 | unsigned long flags; | |
| 29 | ||
| 30 | reset = container_of(rcdev, struct zx2967_reset, rcdev); | |
| 31 | ||
| 32 | spin_lock_irqsave(&reset->lock, flags); | |
| 33 | ||
| 34 | reg = readl_relaxed(reset->reg_base + (bank * 4)); | |
| 35 | if (assert) | |
| 36 | reg &= ~BIT(offset); | |
| 37 | else | |
| 38 | reg |= BIT(offset); | |
| 39 | writel_relaxed(reg, reset->reg_base + (bank * 4)); | |
| 40 | ||
| 41 | spin_unlock_irqrestore(&reset->lock, flags); | |
| 42 | ||
| 43 | return 0; | |
| 44 | } | |
| 45 | ||
| 46 | static int zx2967_reset_assert(struct reset_controller_dev *rcdev, | |
| 47 | unsigned long id) | |
| 48 | { | |
| 49 | return zx2967_reset_act(rcdev, id, true); | |
| 50 | } | |
| 51 | ||
| 52 | static int zx2967_reset_deassert(struct reset_controller_dev *rcdev, | |
| 53 | unsigned long id) | |
| 54 | { | |
| 55 | return zx2967_reset_act(rcdev, id, false); | |
| 56 | } | |
| 57 | ||
| 58 | static struct reset_control_ops zx2967_reset_ops = { | |
| 59 | .assert = zx2967_reset_assert, | |
| 60 | .deassert = zx2967_reset_deassert, | |
| 61 | }; | |
| 62 | ||
| 63 | static int zx2967_reset_probe(struct platform_device *pdev) | |
| 64 | { | |
| 65 | struct zx2967_reset *reset; | |
| 66 | struct resource *res; | |
| 67 | ||
| 68 | reset = devm_kzalloc(&pdev->dev, sizeof(*reset), GFP_KERNEL); | |
| 69 | if (!reset) | |
| 70 | return -ENOMEM; | |
| 71 | ||
| 72 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
| 73 | reset->reg_base = devm_ioremap_resource(&pdev->dev, res); | |
| 74 | if (IS_ERR(reset->reg_base)) | |
| 75 | return PTR_ERR(reset->reg_base); | |
| 76 | ||
| 77 | spin_lock_init(&reset->lock); | |
| 78 | ||
| 79 | reset->rcdev.owner = THIS_MODULE; | |
| 80 | reset->rcdev.nr_resets = resource_size(res) * 8; | |
| 81 | reset->rcdev.ops = &zx2967_reset_ops; | |
| 82 | reset->rcdev.of_node = pdev->dev.of_node; | |
| 83 | ||
| 84 | return devm_reset_controller_register(&pdev->dev, &reset->rcdev); | |
| 85 | } | |
| 86 | ||
| 87 | static const struct of_device_id zx2967_reset_dt_ids[] = { | |
| 88 | { .compatible = "zte,zx296718-reset", }, | |
| 89 | {}, | |
| 90 | }; | |
| b38386f4 BX |
91 | |
| 92 | static struct platform_driver zx2967_reset_driver = { | |
| 93 | .probe = zx2967_reset_probe, | |
| 94 | .driver = { | |
| 95 | .name = "zx2967-reset", | |
| 96 | .of_match_table = zx2967_reset_dt_ids, | |
| 97 | }, | |
| 98 | }; | |
| b38386f4 | 99 | builtin_platform_driver(zx2967_reset_driver); |