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| Commit | Line | Data |
|---|---|---|
| 8a4e6154 MF |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 2 | /* | |
| 3 | * TI TPS380x Supply Voltage Supervisor and Reset Controller Driver | |
| 4 | * | |
| 5 | * Copyright (C) 2022 Pengutronix, Marco Felsch <[email protected]> | |
| 6 | * | |
| 7 | * Based on Simple Reset Controller Driver | |
| 8 | * | |
| 9 | * Copyright (C) 2017 Pengutronix, Philipp Zabel <[email protected]> | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/delay.h> | |
| 13 | #include <linux/gpio/consumer.h> | |
| 14 | #include <linux/module.h> | |
| 15 | #include <linux/of.h> | |
| 16 | #include <linux/platform_device.h> | |
| 17 | #include <linux/property.h> | |
| 18 | #include <linux/reset-controller.h> | |
| 19 | ||
| 20 | struct tps380x_reset { | |
| 21 | struct reset_controller_dev rcdev; | |
| 22 | struct gpio_desc *reset_gpio; | |
| 23 | unsigned int reset_ms; | |
| 24 | }; | |
| 25 | ||
| 26 | struct tps380x_reset_devdata { | |
| 27 | unsigned int min_reset_ms; | |
| 28 | unsigned int typ_reset_ms; | |
| 29 | unsigned int max_reset_ms; | |
| 30 | }; | |
| 31 | ||
| 32 | static inline | |
| 33 | struct tps380x_reset *to_tps380x_reset(struct reset_controller_dev *rcdev) | |
| 34 | { | |
| 35 | return container_of(rcdev, struct tps380x_reset, rcdev); | |
| 36 | } | |
| 37 | ||
| 38 | static int | |
| 39 | tps380x_reset_assert(struct reset_controller_dev *rcdev, unsigned long id) | |
| 40 | { | |
| 41 | struct tps380x_reset *tps380x = to_tps380x_reset(rcdev); | |
| 42 | ||
| 43 | gpiod_set_value_cansleep(tps380x->reset_gpio, 1); | |
| 44 | ||
| 45 | return 0; | |
| 46 | } | |
| 47 | ||
| 48 | static int | |
| 49 | tps380x_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id) | |
| 50 | { | |
| 51 | struct tps380x_reset *tps380x = to_tps380x_reset(rcdev); | |
| 52 | ||
| 53 | gpiod_set_value_cansleep(tps380x->reset_gpio, 0); | |
| 54 | msleep(tps380x->reset_ms); | |
| 55 | ||
| 56 | return 0; | |
| 57 | } | |
| 58 | ||
| 59 | static const struct reset_control_ops reset_tps380x_ops = { | |
| 60 | .assert = tps380x_reset_assert, | |
| 61 | .deassert = tps380x_reset_deassert, | |
| 62 | }; | |
| 63 | ||
| 64 | static int tps380x_reset_of_xlate(struct reset_controller_dev *rcdev, | |
| 65 | const struct of_phandle_args *reset_spec) | |
| 66 | { | |
| 67 | /* No special handling needed, we have only one reset line per device */ | |
| 68 | return 0; | |
| 69 | } | |
| 70 | ||
| 71 | static int tps380x_reset_probe(struct platform_device *pdev) | |
| 72 | { | |
| 73 | struct device *dev = &pdev->dev; | |
| 74 | const struct tps380x_reset_devdata *devdata; | |
| 75 | struct tps380x_reset *tps380x; | |
| 76 | ||
| 77 | devdata = device_get_match_data(dev); | |
| 78 | if (!devdata) | |
| 79 | return -EINVAL; | |
| 80 | ||
| 81 | tps380x = devm_kzalloc(dev, sizeof(*tps380x), GFP_KERNEL); | |
| 82 | if (!tps380x) | |
| 83 | return -ENOMEM; | |
| 84 | ||
| 85 | tps380x->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); | |
| 86 | if (IS_ERR(tps380x->reset_gpio)) | |
| 87 | return dev_err_probe(dev, PTR_ERR(tps380x->reset_gpio), | |
| 88 | "Failed to get GPIO\n"); | |
| 89 | ||
| 90 | tps380x->reset_ms = devdata->max_reset_ms; | |
| 91 | ||
| 92 | tps380x->rcdev.ops = &reset_tps380x_ops; | |
| 93 | tps380x->rcdev.owner = THIS_MODULE; | |
| 94 | tps380x->rcdev.dev = dev; | |
| 95 | tps380x->rcdev.of_node = dev->of_node; | |
| 96 | tps380x->rcdev.of_reset_n_cells = 0; | |
| 97 | tps380x->rcdev.of_xlate = tps380x_reset_of_xlate; | |
| 98 | tps380x->rcdev.nr_resets = 1; | |
| 99 | ||
| 100 | return devm_reset_controller_register(dev, &tps380x->rcdev); | |
| 101 | } | |
| 102 | ||
| 103 | static const struct tps380x_reset_devdata tps3801_reset_data = { | |
| 104 | .min_reset_ms = 120, | |
| 105 | .typ_reset_ms = 200, | |
| 106 | .max_reset_ms = 280, | |
| 107 | }; | |
| 108 | ||
| 109 | static const struct of_device_id tps380x_reset_dt_ids[] = { | |
| 110 | { .compatible = "ti,tps3801", .data = &tps3801_reset_data }, | |
| 111 | { /* sentinel */ }, | |
| 112 | }; | |
| 113 | MODULE_DEVICE_TABLE(of, tps380x_reset_dt_ids); | |
| 114 | ||
| 115 | static struct platform_driver tps380x_reset_driver = { | |
| 116 | .probe = tps380x_reset_probe, | |
| 117 | .driver = { | |
| 118 | .name = "tps380x-reset", | |
| 119 | .of_match_table = tps380x_reset_dt_ids, | |
| 120 | }, | |
| 121 | }; | |
| 122 | module_platform_driver(tps380x_reset_driver); | |
| 123 | ||
| 124 | MODULE_AUTHOR("Marco Felsch <[email protected]>"); | |
| d985db83 | 125 | MODULE_DESCRIPTION("TI TPS380x Supply Voltage Supervisor and Reset Driver"); |
| 8a4e6154 | 126 | MODULE_LICENSE("GPL v2"); |