1 /* 2 * Copyright 2015 Red Hat Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * 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 OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * Authors: Ben Skeggs <bskeggs@redhat.com> 23 */ 24 #include "pad.h" 25 26 static void 27 nvkm_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 35 void 36 nvkm_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 45 void 46 nvkm_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 54 int 55 nvkm_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 69 void 70 nvkm_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 76 void 77 nvkm_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 83 void 84 nvkm_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 95 void 96 nvkm_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 } 107 108 int 109 nvkm_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