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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 "bus.h"25#include "pad.h"26 27#include <core/option.h>28 29/*******************************************************************************30 * i2c-algo-bit31 ******************************************************************************/32static int33nvkm_i2c_bus_pre_xfer(struct i2c_adapter *adap)34{35 struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);36 return nvkm_i2c_bus_acquire(bus);37}38 39static void40nvkm_i2c_bus_post_xfer(struct i2c_adapter *adap)41{42 struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);43 return nvkm_i2c_bus_release(bus);44}45 46static void47nvkm_i2c_bus_setscl(void *data, int state)48{49 struct nvkm_i2c_bus *bus = data;50 bus->func->drive_scl(bus, state);51}52 53static void54nvkm_i2c_bus_setsda(void *data, int state)55{56 struct nvkm_i2c_bus *bus = data;57 bus->func->drive_sda(bus, state);58}59 60static int61nvkm_i2c_bus_getscl(void *data)62{63 struct nvkm_i2c_bus *bus = data;64 return bus->func->sense_scl(bus);65}66 67static int68nvkm_i2c_bus_getsda(void *data)69{70 struct nvkm_i2c_bus *bus = data;71 return bus->func->sense_sda(bus);72}73 74/*******************************************************************************75 * !i2c-algo-bit (off-chip i2c bus / hw i2c / internal bit-banging algo)76 ******************************************************************************/77static int78nvkm_i2c_bus_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)79{80 struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);81 int ret;82 83 ret = nvkm_i2c_bus_acquire(bus);84 if (ret)85 return ret;86 87 ret = bus->func->xfer(bus, msgs, num);88 nvkm_i2c_bus_release(bus);89 return ret;90}91 92static u3293nvkm_i2c_bus_func(struct i2c_adapter *adap)94{95 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;96}97 98static const struct i2c_algorithm99nvkm_i2c_bus_algo = {100 .master_xfer = nvkm_i2c_bus_xfer,101 .functionality = nvkm_i2c_bus_func,102};103 104/*******************************************************************************105 * nvkm_i2c_bus base106 ******************************************************************************/107void108nvkm_i2c_bus_init(struct nvkm_i2c_bus *bus)109{110 BUS_TRACE(bus, "init");111 if (bus->func->init)112 bus->func->init(bus);113 114 mutex_lock(&bus->mutex);115 bus->enabled = true;116 mutex_unlock(&bus->mutex);117}118 119void120nvkm_i2c_bus_fini(struct nvkm_i2c_bus *bus)121{122 BUS_TRACE(bus, "fini");123 mutex_lock(&bus->mutex);124 bus->enabled = false;125 mutex_unlock(&bus->mutex);126}127 128void129nvkm_i2c_bus_release(struct nvkm_i2c_bus *bus)130{131 struct nvkm_i2c_pad *pad = bus->pad;132 BUS_TRACE(bus, "release");133 nvkm_i2c_pad_release(pad);134 mutex_unlock(&bus->mutex);135}136 137int138nvkm_i2c_bus_acquire(struct nvkm_i2c_bus *bus)139{140 struct nvkm_i2c_pad *pad = bus->pad;141 int ret;142 143 BUS_TRACE(bus, "acquire");144 mutex_lock(&bus->mutex);145 146 if (bus->enabled)147 ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_I2C);148 else149 ret = -EIO;150 151 if (ret)152 mutex_unlock(&bus->mutex);153 return ret;154}155 156int157nvkm_i2c_bus_probe(struct nvkm_i2c_bus *bus, const char *what,158 struct nvkm_i2c_bus_probe *info,159 bool (*match)(struct nvkm_i2c_bus *,160 struct i2c_board_info *, void *), void *data)161{162 int i;163 164 BUS_DBG(bus, "probing %ss", what);165 for (i = 0; info[i].dev.addr; i++) {166 u8 orig_udelay = 0;167 168 if ((bus->i2c.algo == &i2c_bit_algo) && (info[i].udelay != 0)) {169 struct i2c_algo_bit_data *algo = bus->i2c.algo_data;170 BUS_DBG(bus, "%dms delay instead of %dms",171 info[i].udelay, algo->udelay);172 orig_udelay = algo->udelay;173 algo->udelay = info[i].udelay;174 }175 176 if (nvkm_probe_i2c(&bus->i2c, info[i].dev.addr) &&177 (!match || match(bus, &info[i].dev, data))) {178 BUS_DBG(bus, "detected %s: %s",179 what, info[i].dev.type);180 return i;181 }182 183 if (orig_udelay) {184 struct i2c_algo_bit_data *algo = bus->i2c.algo_data;185 algo->udelay = orig_udelay;186 }187 }188 189 BUS_DBG(bus, "no devices found.");190 return -ENODEV;191}192 193void194nvkm_i2c_bus_del(struct nvkm_i2c_bus **pbus)195{196 struct nvkm_i2c_bus *bus = *pbus;197 if (bus && !WARN_ON(!bus->func)) {198 BUS_TRACE(bus, "dtor");199 list_del(&bus->head);200 i2c_del_adapter(&bus->i2c);201 kfree(bus->i2c.algo_data);202 kfree(*pbus);203 *pbus = NULL;204 }205}206 207int208nvkm_i2c_bus_ctor(const struct nvkm_i2c_bus_func *func,209 struct nvkm_i2c_pad *pad, int id,210 struct nvkm_i2c_bus *bus)211{212 struct nvkm_device *device = pad->i2c->subdev.device;213 struct i2c_algo_bit_data *bit;214#ifndef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT215 const bool internal = false;216#else217 const bool internal = true;218#endif219 int ret;220 221 bus->func = func;222 bus->pad = pad;223 bus->id = id;224 mutex_init(&bus->mutex);225 list_add_tail(&bus->head, &pad->i2c->bus);226 BUS_TRACE(bus, "ctor");227 228 snprintf(bus->i2c.name, sizeof(bus->i2c.name), "nvkm-%s-bus-%04x",229 dev_name(device->dev), id);230 bus->i2c.owner = THIS_MODULE;231 bus->i2c.dev.parent = device->dev;232 233 if ( bus->func->drive_scl &&234 !nvkm_boolopt(device->cfgopt, "NvI2C", internal)) {235 if (!(bit = kzalloc(sizeof(*bit), GFP_KERNEL)))236 return -ENOMEM;237 bit->udelay = 10;238 bit->timeout = usecs_to_jiffies(2200);239 bit->data = bus;240 bit->pre_xfer = nvkm_i2c_bus_pre_xfer;241 bit->post_xfer = nvkm_i2c_bus_post_xfer;242 bit->setscl = nvkm_i2c_bus_setscl;243 bit->setsda = nvkm_i2c_bus_setsda;244 bit->getscl = nvkm_i2c_bus_getscl;245 bit->getsda = nvkm_i2c_bus_getsda;246 bus->i2c.algo_data = bit;247 ret = i2c_bit_add_bus(&bus->i2c);248 } else {249 bus->i2c.algo = &nvkm_i2c_bus_algo;250 ret = i2c_add_adapter(&bus->i2c);251 }252 253 return ret;254}255 256int257nvkm_i2c_bus_new_(const struct nvkm_i2c_bus_func *func,258 struct nvkm_i2c_pad *pad, int id,259 struct nvkm_i2c_bus **pbus)260{261 if (!(*pbus = kzalloc(sizeof(**pbus), GFP_KERNEL)))262 return -ENOMEM;263 return nvkm_i2c_bus_ctor(func, pad, id, *pbus);264}265