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