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1/*2 * Copyright 2015 Red Hat Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice shall be included in12 * all copies or substantial portions of the Software.13 *14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR20 * OTHER DEALINGS IN THE SOFTWARE.21 *22 * Authors: Ben Skeggs <bskeggs@redhat.com>23 */24#include "pad.h"25 26static void27nvkm_i2c_pad_mode_locked(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode)28{29 PAD_TRACE(pad, "-> %s", (mode == NVKM_I2C_PAD_AUX) ? "aux" :30 (mode == NVKM_I2C_PAD_I2C) ? "i2c" : "off");31 if (pad->func->mode)32 pad->func->mode(pad, mode);33}34 35void36nvkm_i2c_pad_mode(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode)37{38 PAD_TRACE(pad, "mode %d", mode);39 mutex_lock(&pad->mutex);40 nvkm_i2c_pad_mode_locked(pad, mode);41 pad->mode = mode;42 mutex_unlock(&pad->mutex);43}44 45void46nvkm_i2c_pad_release(struct nvkm_i2c_pad *pad)47{48 PAD_TRACE(pad, "release");49 if (pad->mode == NVKM_I2C_PAD_OFF)50 nvkm_i2c_pad_mode_locked(pad, pad->mode);51 mutex_unlock(&pad->mutex);52}53 54int55nvkm_i2c_pad_acquire(struct nvkm_i2c_pad *pad, enum nvkm_i2c_pad_mode mode)56{57 PAD_TRACE(pad, "acquire");58 mutex_lock(&pad->mutex);59 if (pad->mode != mode) {60 if (pad->mode != NVKM_I2C_PAD_OFF) {61 mutex_unlock(&pad->mutex);62 return -EBUSY;63 }64 nvkm_i2c_pad_mode_locked(pad, mode);65 }66 return 0;67}68 69void70nvkm_i2c_pad_fini(struct nvkm_i2c_pad *pad)71{72 PAD_TRACE(pad, "fini");73 nvkm_i2c_pad_mode_locked(pad, NVKM_I2C_PAD_OFF);74}75 76void77nvkm_i2c_pad_init(struct nvkm_i2c_pad *pad)78{79 PAD_TRACE(pad, "init");80 nvkm_i2c_pad_mode_locked(pad, pad->mode);81}82 83void84nvkm_i2c_pad_del(struct nvkm_i2c_pad **ppad)85{86 struct nvkm_i2c_pad *pad = *ppad;87 if (pad) {88 PAD_TRACE(pad, "dtor");89 list_del(&pad->head);90 kfree(pad);91 pad = NULL;92 }93}94 95void96nvkm_i2c_pad_ctor(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c,97 int id, struct nvkm_i2c_pad *pad)98{99 pad->func = func;100 pad->i2c = i2c;101 pad->id = id;102 pad->mode = NVKM_I2C_PAD_OFF;103 mutex_init(&pad->mutex);104 list_add_tail(&pad->head, &i2c->pad);105 PAD_TRACE(pad, "ctor");106}107 108int109nvkm_i2c_pad_new_(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c,110 int id, struct nvkm_i2c_pad **ppad)111{112 if (!(*ppad = kzalloc(sizeof(**ppad), GFP_KERNEL)))113 return -ENOMEM;114 nvkm_i2c_pad_ctor(func, i2c, id, *ppad);115 return 0;116}117