/*
* Copyright 2015 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs <[email protected]>
*/
#include "bus.h"
#include "pad.h"
#include <core/option.h>
/*******************************************************************************
* i2c-algo-bit
******************************************************************************/
static int
nvkm_i2c_bus_pre_xfer(struct i2c_adapter *adap)
{
struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
return nvkm_i2c_bus_acquire(bus);
}
static void
nvkm_i2c_bus_post_xfer(struct i2c_adapter *adap)
{
struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
return nvkm_i2c_bus_release(bus);
}
static void
nvkm_i2c_bus_setscl(void *data, int state)
{
struct nvkm_i2c_bus *bus = data;
bus->func->drive_scl(bus, state);
}
static void
nvkm_i2c_bus_setsda(void *data, int state)
{
struct nvkm_i2c_bus *bus = data;
bus->func->drive_sda(bus, state);
}
static int
nvkm_i2c_bus_getscl(void *data)
{
struct nvkm_i2c_bus *bus = data;
return bus->func->sense_scl(bus);
}
static int
nvkm_i2c_bus_getsda(void *data)
{
struct nvkm_i2c_bus *bus = data;
return bus->func->sense_sda(bus);
}
/*******************************************************************************
* !i2c-algo-bit (off-chip i2c bus / hw i2c / internal bit-banging algo)
******************************************************************************/
static int
nvkm_i2c_bus_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
int ret;
ret = nvkm_i2c_bus_acquire(bus);
if (ret)
return ret;
ret = bus->func->xfer(bus, msgs, num);
nvkm_i2c_bus_release(bus);
return ret;
}
static u32
nvkm_i2c_bus_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm
nvkm_i2c_bus_algo = {
.master_xfer = nvkm_i2c_bus_xfer,
.functionality = nvkm_i2c_bus_func,
};
/*******************************************************************************
* nvkm_i2c_bus base
******************************************************************************/
void
nvkm_i2c_bus_init(struct nvkm_i2c_bus *bus)
{
BUS_TRACE(bus, "init");
if (bus->func->init)
bus->func->init(bus);
mutex_lock(&bus->mutex);
bus->enabled = true;
mutex_unlock(&bus->mutex);
}
void
nvkm_i2c_bus_fini(struct nvkm_i2c_bus *bus)
{
BUS_TRACE(bus, "fini");
mutex_lock(&bus->mutex);
bus->enabled = false;
mutex_unlock(&bus->mutex);
}
void
nvkm_i2c_bus_release(struct nvkm_i2c_bus *bus)
{
struct nvkm_i2c_pad *pad = bus->pad;
BUS_TRACE(bus, "release");
nvkm_i2c_pad_release(pad);
mutex_unlock(&bus->mutex);
}
int
nvkm_i2c_bus_acquire(struct nvkm_i2c_bus *bus)
{
struct nvkm_i2c_pad *pad = bus->pad;
int ret;
BUS_TRACE(bus, "acquire");
mutex_lock(&bus->mutex);
if (bus->enabled)
ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_I2C);
else
ret = -EIO;
if (ret)
mutex_unlock(&bus->mutex);
return ret;
}
int
nvkm_i2c_bus_probe(struct nvkm_i2c_bus *bus, const char *what,
struct nvkm_i2c_bus_probe *info,
bool (*match)(struct nvkm_i2c_bus *,
struct i2c_board_info *, void *), void *data)
{
int i;
BUS_DBG(bus, "probing %ss", what);
for (i = 0; info[i].dev.addr; i++) {
u8 orig_udelay = 0;
if ((bus->i2c.algo == &i2c_bit_algo) && (info[i].udelay != 0)) {
struct i2c_algo_bit_data *algo = bus->i2c.algo_data;
BUS_DBG(bus, "%dms delay instead of %dms",
info[i].udelay, algo->udelay);
orig_udelay = algo->udelay;
algo->udelay = info[i].udelay;
}
if (nvkm_probe_i2c(&bus->i2c, info[i].dev.addr) &&
(!match || match(bus, &info[i].dev, data))) {
BUS_DBG(bus, "detected %s: %s",
what, info[i].dev.type);
return i;
}
if (orig_udelay) {
struct i2c_algo_bit_data *algo = bus->i2c.algo_data;
algo->udelay = orig_udelay;
}
}
BUS_DBG(bus, "no devices found.");
return -ENODEV;
}
void
nvkm_i2c_bus_del(struct nvkm_i2c_bus **pbus)
{
struct nvkm_i2c_bus *bus = *pbus;
if (bus && !WARN_ON(!bus->func)) {
BUS_TRACE(bus, "dtor");
list_del(&bus->head);
i2c_del_adapter(&bus->i2c);
kfree(bus->i2c.algo_data);
kfree(*pbus);
*pbus = NULL;
}
}
int
nvkm_i2c_bus_ctor(const struct nvkm_i2c_bus_func *func,
struct nvkm_i2c_pad *pad, int id,
struct nvkm_i2c_bus *bus)
{
struct nvkm_device *device = pad->i2c->subdev.device;
struct i2c_algo_bit_data *bit;
#ifndef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT
const bool internal = false;
#else
const bool internal = true;
#endif
int ret;
bus->func = func;
bus->pad = pad;
bus->id = id;
mutex_init(&bus->mutex);
list_add_tail(&bus->head, &pad->i2c->bus);
BUS_TRACE(bus, "ctor");
snprintf(bus->i2c.name, sizeof(bus->i2c.name), "nvkm-%s-bus-%04x",
dev_name(device->dev), id);
bus->i2c.owner = THIS_MODULE;
bus->i2c.dev.parent = device->dev;
if ( bus->func->drive_scl &&
!nvkm_boolopt(device->cfgopt, "NvI2C", internal)) {
if (!(bit = kzalloc(sizeof(*bit), GFP_KERNEL)))
return -ENOMEM;
bit->udelay = 10;
bit->timeout = usecs_to_jiffies(2200);
bit->data = bus;
bit->pre_xfer = nvkm_i2c_bus_pre_xfer;
bit->post_xfer = nvkm_i2c_bus_post_xfer;
bit->setscl = nvkm_i2c_bus_setscl;
bit->setsda = nvkm_i2c_bus_setsda;
bit->getscl = nvkm_i2c_bus_getscl;
bit->getsda = nvkm_i2c_bus_getsda;
bus->i2c.algo_data = bit;
ret = i2c_bit_add_bus(&bus->i2c);
} else {
bus->i2c.algo = &nvkm_i2c_bus_algo;
ret = i2c_add_adapter(&bus->i2c);
}
return ret;
}
int
nvkm_i2c_bus_new_(const struct nvkm_i2c_bus_func *func,
struct nvkm_i2c_pad *pad, int id,
struct nvkm_i2c_bus **pbus)
{
if (!(*pbus = kzalloc(sizeof(**pbus), GFP_KERNEL)))
return -ENOMEM;
return nvkm_i2c_bus_ctor(func, pad, id, *pbus);
}
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