1/* $NetBSD: nouveau_nvkm_subdev_i2c_pad.c,v 1.5 2021/12/18 23:45:40 riastradh Exp $ */ 2 3/* 4 * Copyright 2015 Red Hat Inc. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 22 * OTHER DEALINGS IN THE SOFTWARE. 23 * 24 * Authors: Ben Skeggs <bskeggs@redhat.com> 25 */ 26#include <sys/cdefs.h> 27__KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_i2c_pad.c,v 1.5 2021/12/18 23:45:40 riastradh Exp $"); 28 29#include "pad.h" 30 31#include <linux/nbsd-namespace.h> 32 33static void 34nvkm_i2c_pad_mode_locked(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode) 35{ 36 PAD_TRACE(pad, "-> %s", (mode == NVKM_I2C_PAD_AUX) ? "aux" : 37 (mode == NVKM_I2C_PAD_I2C) ? "i2c" : "off"); 38 if (pad->func->mode) 39 pad->func->mode(pad, mode); 40} 41 42void 43nvkm_i2c_pad_mode(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode) 44{ 45 PAD_TRACE(pad, "mode %d", mode); 46 mutex_lock(&pad->mutex); 47 nvkm_i2c_pad_mode_locked(pad, mode); 48 pad->mode = mode; 49 mutex_unlock(&pad->mutex); 50} 51 52void 53nvkm_i2c_pad_release(struct nvkm_i2c_pad *pad) 54{ 55 PAD_TRACE(pad, "release"); 56 if (pad->mode == NVKM_I2C_PAD_OFF) 57 nvkm_i2c_pad_mode_locked(pad, pad->mode); 58 mutex_unlock(&pad->mutex); 59} 60 61int 62nvkm_i2c_pad_acquire(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode) 63{ 64 PAD_TRACE(pad, "acquire"); 65 mutex_lock(&pad->mutex); 66 if (pad->mode != mode) { 67 if (pad->mode != NVKM_I2C_PAD_OFF) { 68 mutex_unlock(&pad->mutex); 69 return -EBUSY; 70 } 71 nvkm_i2c_pad_mode_locked(pad, mode); 72 } 73 return 0; 74} 75 76void 77nvkm_i2c_pad_fini(struct nvkm_i2c_pad *pad) 78{ 79 PAD_TRACE(pad, "fini"); 80 nvkm_i2c_pad_mode_locked(pad, NVKM_I2C_PAD_OFF); 81} 82 83void 84nvkm_i2c_pad_init(struct nvkm_i2c_pad *pad) 85{ 86 PAD_TRACE(pad, "init"); 87 nvkm_i2c_pad_mode_locked(pad, pad->mode); 88} 89 90void 91nvkm_i2c_pad_del(struct nvkm_i2c_pad **ppad) 92{ 93 struct nvkm_i2c_pad *pad = *ppad; 94 if (pad) { 95 PAD_TRACE(pad, "dtor"); 96 list_del(&pad->head); 97 mutex_destroy(&pad->mutex); 98 kfree(pad); 99 pad = NULL; 100 } 101} 102 103void 104nvkm_i2c_pad_ctor(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c, 105 int id, struct nvkm_i2c_pad *pad) 106{ 107 pad->func = func; 108 pad->i2c = i2c; 109 pad->id = id; 110 pad->mode = NVKM_I2C_PAD_OFF; 111 mutex_init(&pad->mutex); 112 list_add_tail(&pad->head, &i2c->pad); 113 PAD_TRACE(pad, "ctor"); 114} 115 116int 117nvkm_i2c_pad_new_(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c, 118 int id, struct nvkm_i2c_pad **ppad) 119{ 120 if (!(*ppad = kzalloc(sizeof(**ppad), GFP_KERNEL))) 121 return -ENOMEM; 122 nvkm_i2c_pad_ctor(func, i2c, id, *ppad); 123 return 0; 124} 125