1 /* 2 * Copyright 2009 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 23 */ 24 #include "aux.h" 25 #include "pad.h" 26 27 static int 28 nvkm_i2c_aux_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 29 { 30 struct nvkm_i2c_aux *aux = container_of(adap, typeof(*aux), i2c); 31 struct i2c_msg *msg = msgs; 32 int ret, mcnt = num; 33 34 ret = nvkm_i2c_aux_acquire(aux); 35 if (ret) 36 return ret; 37 38 while (mcnt--) { 39 u8 remaining = msg->len; 40 u8 *ptr = msg->buf; 41 42 while (remaining) { 43 u8 cnt, retries, cmd; 44 45 if (msg->flags & I2C_M_RD) 46 cmd = 1; 47 else 48 cmd = 0; 49 50 if (mcnt || remaining > 16) 51 cmd |= 4; /* MOT */ 52 53 for (retries = 0, cnt = 0; 54 retries < 32 && !cnt; 55 retries++) { 56 cnt = min_t(u8, remaining, 16); 57 ret = aux->func->xfer(aux, true, cmd, 58 msg->addr, ptr, &cnt); 59 if (ret < 0) 60 goto out; 61 } 62 if (!cnt) { 63 AUX_TRACE(aux, "no data after 32 retries"); 64 ret = -EIO; 65 goto out; 66 } 67 68 ptr += cnt; 69 remaining -= cnt; 70 } 71 72 msg++; 73 } 74 75 ret = num; 76 out: 77 nvkm_i2c_aux_release(aux); 78 return ret; 79 } 80 81 static u32 82 nvkm_i2c_aux_i2c_func(struct i2c_adapter *adap) 83 { 84 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 85 } 86 87 static const struct i2c_algorithm 88 nvkm_i2c_aux_i2c_algo = { 89 .master_xfer = nvkm_i2c_aux_i2c_xfer, 90 .functionality = nvkm_i2c_aux_i2c_func 91 }; 92 93 void 94 nvkm_i2c_aux_monitor(struct nvkm_i2c_aux *aux, bool monitor) 95 { 96 struct nvkm_i2c_pad *pad = aux->pad; 97 AUX_TRACE(aux, "monitor: %s", monitor ? "yes" : "no"); 98 if (monitor) 99 nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_AUX); 100 else 101 nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_OFF); 102 } 103 104 void 105 nvkm_i2c_aux_release(struct nvkm_i2c_aux *aux) 106 { 107 struct nvkm_i2c_pad *pad = aux->pad; 108 AUX_TRACE(aux, "release"); 109 nvkm_i2c_pad_release(pad); 110 mutex_unlock(&aux->mutex); 111 } 112 113 int 114 nvkm_i2c_aux_acquire(struct nvkm_i2c_aux *aux) 115 { 116 struct nvkm_i2c_pad *pad = aux->pad; 117 int ret; 118 119 AUX_TRACE(aux, "acquire"); 120 mutex_lock(&aux->mutex); 121 122 if (aux->enabled) 123 ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_AUX); 124 else 125 ret = -EIO; 126 127 if (ret) 128 mutex_unlock(&aux->mutex); 129 return ret; 130 } 131 132 int 133 nvkm_i2c_aux_xfer(struct nvkm_i2c_aux *aux, bool retry, u8 type, 134 u32 addr, u8 *data, u8 *size) 135 { 136 if (!*size && !aux->func->address_only) { 137 AUX_ERR(aux, "address-only transaction dropped"); 138 return -ENOSYS; 139 } 140 return aux->func->xfer(aux, retry, type, addr, data, size); 141 } 142 143 int 144 nvkm_i2c_aux_lnk_ctl(struct nvkm_i2c_aux *aux, int nr, int bw, bool ef) 145 { 146 if (aux->func->lnk_ctl) 147 return aux->func->lnk_ctl(aux, nr, bw, ef); 148 return -ENODEV; 149 } 150 151 void 152 nvkm_i2c_aux_del(struct nvkm_i2c_aux **paux) 153 { 154 struct nvkm_i2c_aux *aux = *paux; 155 if (aux && !WARN_ON(!aux->func)) { 156 AUX_TRACE(aux, "dtor"); 157 list_del(&aux->head); 158 i2c_del_adapter(&aux->i2c); 159 kfree(*paux); 160 *paux = NULL; 161 } 162 } 163 164 void 165 nvkm_i2c_aux_init(struct nvkm_i2c_aux *aux) 166 { 167 AUX_TRACE(aux, "init"); 168 mutex_lock(&aux->mutex); 169 aux->enabled = true; 170 mutex_unlock(&aux->mutex); 171 } 172 173 void 174 nvkm_i2c_aux_fini(struct nvkm_i2c_aux *aux) 175 { 176 AUX_TRACE(aux, "fini"); 177 mutex_lock(&aux->mutex); 178 aux->enabled = false; 179 mutex_unlock(&aux->mutex); 180 } 181 182 int 183 nvkm_i2c_aux_ctor(const struct nvkm_i2c_aux_func *func, 184 struct nvkm_i2c_pad *pad, int id, 185 struct nvkm_i2c_aux *aux) 186 { 187 struct nvkm_device *device = pad->i2c->subdev.device; 188 189 aux->func = func; 190 aux->pad = pad; 191 aux->id = id; 192 mutex_init(&aux->mutex); 193 list_add_tail(&aux->head, &pad->i2c->aux); 194 AUX_TRACE(aux, "ctor"); 195 196 snprintf(aux->i2c.name, sizeof(aux->i2c.name), "nvkm-%s-aux-%04x", 197 dev_name(device->dev), id); 198 aux->i2c.owner = THIS_MODULE; 199 aux->i2c.dev.parent = device->dev; 200 aux->i2c.algo = &nvkm_i2c_aux_i2c_algo; 201 return i2c_add_adapter(&aux->i2c); 202 } 203 204 int 205 nvkm_i2c_aux_new_(const struct nvkm_i2c_aux_func *func, 206 struct nvkm_i2c_pad *pad, int id, 207 struct nvkm_i2c_aux **paux) 208 { 209 if (!(*paux = kzalloc(sizeof(**paux), GFP_KERNEL))) 210 return -ENOMEM; 211 return nvkm_i2c_aux_ctor(func, pad, id, *paux); 212 } 213