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| Commit | Line | Data |
|---|---|---|
| bd13251f AT |
1 | /* |
| 2 | * Copyright (C) 2014 Marvell Technology Group Ltd. | |
| 3 | * | |
| ed4dba99 PG |
4 | * Marvell Berlin reset driver |
| 5 | * | |
| bd13251f AT |
6 | * Antoine Tenart <[email protected]> |
| 7 | * Sebastian Hesselbarth <[email protected]> | |
| 8 | * | |
| 9 | * This file is licensed under the terms of the GNU General Public | |
| 10 | * License version 2. This program is licensed "as is" without any | |
| 11 | * warranty of any kind, whether express or implied. | |
| 12 | */ | |
| 13 | ||
| 14 | #include <linux/delay.h> | |
| 15 | #include <linux/io.h> | |
| aed6f3ca | 16 | #include <linux/mfd/syscon.h> |
| ed4dba99 | 17 | #include <linux/init.h> |
| bd13251f AT |
18 | #include <linux/of.h> |
| 19 | #include <linux/of_address.h> | |
| 20 | #include <linux/platform_device.h> | |
| aed6f3ca | 21 | #include <linux/regmap.h> |
| bd13251f AT |
22 | #include <linux/reset-controller.h> |
| 23 | #include <linux/slab.h> | |
| 24 | #include <linux/types.h> | |
| 25 | ||
| 26 | #define BERLIN_MAX_RESETS 32 | |
| 27 | ||
| 28 | #define to_berlin_reset_priv(p) \ | |
| 29 | container_of((p), struct berlin_reset_priv, rcdev) | |
| 30 | ||
| 31 | struct berlin_reset_priv { | |
| aed6f3ca | 32 | struct regmap *regmap; |
| bd13251f AT |
33 | struct reset_controller_dev rcdev; |
| 34 | }; | |
| 35 | ||
| 36 | static int berlin_reset_reset(struct reset_controller_dev *rcdev, | |
| 37 | unsigned long id) | |
| 38 | { | |
| 39 | struct berlin_reset_priv *priv = to_berlin_reset_priv(rcdev); | |
| 40 | int offset = id >> 8; | |
| 41 | int mask = BIT(id & 0x1f); | |
| 42 | ||
| bfff6296 | 43 | regmap_write(priv->regmap, offset, mask); |
| bd13251f AT |
44 | |
| 45 | /* let the reset be effective */ | |
| 46 | udelay(10); | |
| 47 | ||
| 48 | return 0; | |
| 49 | } | |
| 50 | ||
| b7a90075 | 51 | static const struct reset_control_ops berlin_reset_ops = { |
| bd13251f AT |
52 | .reset = berlin_reset_reset, |
| 53 | }; | |
| 54 | ||
| 55 | static int berlin_reset_xlate(struct reset_controller_dev *rcdev, | |
| 56 | const struct of_phandle_args *reset_spec) | |
| 57 | { | |
| bd13251f AT |
58 | unsigned offset, bit; |
| 59 | ||
| bd13251f AT |
60 | offset = reset_spec->args[0]; |
| 61 | bit = reset_spec->args[1]; | |
| 62 | ||
| bd13251f AT |
63 | if (bit >= BERLIN_MAX_RESETS) |
| 64 | return -EINVAL; | |
| 65 | ||
| 66 | return (offset << 8) | bit; | |
| 67 | } | |
| 68 | ||
| aed6f3ca AT |
69 | static int berlin2_reset_probe(struct platform_device *pdev) |
| 70 | { | |
| 71 | struct device_node *parent_np = of_get_parent(pdev->dev.of_node); | |
| 72 | struct berlin_reset_priv *priv; | |
| 73 | ||
| 74 | priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); | |
| 75 | if (!priv) | |
| 76 | return -ENOMEM; | |
| 77 | ||
| 78 | priv->regmap = syscon_node_to_regmap(parent_np); | |
| 79 | of_node_put(parent_np); | |
| 80 | if (IS_ERR(priv->regmap)) | |
| 81 | return PTR_ERR(priv->regmap); | |
| 82 | ||
| 83 | priv->rcdev.owner = THIS_MODULE; | |
| 84 | priv->rcdev.ops = &berlin_reset_ops; | |
| 85 | priv->rcdev.of_node = pdev->dev.of_node; | |
| 86 | priv->rcdev.of_reset_n_cells = 2; | |
| 87 | priv->rcdev.of_xlate = berlin_reset_xlate; | |
| 88 | ||
| d1f15aa0 | 89 | return reset_controller_register(&priv->rcdev); |
| aed6f3ca AT |
90 | } |
| 91 | ||
| 92 | static const struct of_device_id berlin_reset_dt_match[] = { | |
| 93 | { .compatible = "marvell,berlin2-reset" }, | |
| 94 | { }, | |
| 95 | }; | |
| aed6f3ca AT |
96 | |
| 97 | static struct platform_driver berlin_reset_driver = { | |
| 98 | .probe = berlin2_reset_probe, | |
| 99 | .driver = { | |
| 100 | .name = "berlin2-reset", | |
| 101 | .of_match_table = berlin_reset_dt_match, | |
| 102 | }, | |
| 103 | }; | |
| ed4dba99 | 104 | builtin_platform_driver(berlin_reset_driver); |