diff options
Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c')
| -rw-r--r-- | drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c b/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c new file mode 100644 index 000000000..d063d0dc1 --- /dev/null +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c @@ -0,0 +1,215 @@ +/* + * Copyright 2009 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 + */ + +#include <linux/string_helpers.h> + +#include "aux.h" +#include "pad.h" + +static int +nvkm_i2c_aux_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct nvkm_i2c_aux *aux = container_of(adap, typeof(*aux), i2c); + struct i2c_msg *msg = msgs; + int ret, mcnt = num; + + ret = nvkm_i2c_aux_acquire(aux); + if (ret) + return ret; + + while (mcnt--) { + u8 remaining = msg->len; + u8 *ptr = msg->buf; + + while (remaining) { + u8 cnt, retries, cmd; + + if (msg->flags & I2C_M_RD) + cmd = 1; + else + cmd = 0; + + if (mcnt || remaining > 16) + cmd |= 4; /* MOT */ + + for (retries = 0, cnt = 0; + retries < 32 && !cnt; + retries++) { + cnt = min_t(u8, remaining, 16); + ret = aux->func->xfer(aux, true, cmd, + msg->addr, ptr, &cnt); + if (ret < 0) + goto out; + } + if (!cnt) { + AUX_TRACE(aux, "no data after 32 retries"); + ret = -EIO; + goto out; + } + + ptr += cnt; + remaining -= cnt; + } + + msg++; + } + + ret = num; +out: + nvkm_i2c_aux_release(aux); + return ret; +} + +static u32 +nvkm_i2c_aux_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm +nvkm_i2c_aux_i2c_algo = { + .master_xfer = nvkm_i2c_aux_i2c_xfer, + .functionality = nvkm_i2c_aux_i2c_func +}; + +void +nvkm_i2c_aux_monitor(struct nvkm_i2c_aux *aux, bool monitor) +{ + struct nvkm_i2c_pad *pad = aux->pad; + AUX_TRACE(aux, "monitor: %s", str_yes_no(monitor)); + if (monitor) + nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_AUX); + else + nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_OFF); +} + +void +nvkm_i2c_aux_release(struct nvkm_i2c_aux *aux) +{ + struct nvkm_i2c_pad *pad = aux->pad; + AUX_TRACE(aux, "release"); + nvkm_i2c_pad_release(pad); + mutex_unlock(&aux->mutex); +} + +int +nvkm_i2c_aux_acquire(struct nvkm_i2c_aux *aux) +{ + struct nvkm_i2c_pad *pad = aux->pad; + int ret; + + AUX_TRACE(aux, "acquire"); + mutex_lock(&aux->mutex); + + if (aux->enabled) + ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_AUX); + else + ret = -EIO; + + if (ret) + mutex_unlock(&aux->mutex); + return ret; +} + +int +nvkm_i2c_aux_xfer(struct nvkm_i2c_aux *aux, bool retry, u8 type, + u32 addr, u8 *data, u8 *size) +{ + if (!*size && !aux->func->address_only) { + AUX_ERR(aux, "address-only transaction dropped"); + return -ENOSYS; + } + return aux->func->xfer(aux, retry, type, addr, data, size); +} + +int +nvkm_i2c_aux_lnk_ctl(struct nvkm_i2c_aux *aux, int nr, int bw, bool ef) +{ + if (aux->func->lnk_ctl) + return aux->func->lnk_ctl(aux, nr, bw, ef); + return -ENODEV; +} + +void +nvkm_i2c_aux_del(struct nvkm_i2c_aux **paux) +{ + struct nvkm_i2c_aux *aux = *paux; + if (aux && !WARN_ON(!aux->func)) { + AUX_TRACE(aux, "dtor"); + list_del(&aux->head); + i2c_del_adapter(&aux->i2c); + kfree(*paux); + *paux = NULL; + } +} + +void +nvkm_i2c_aux_init(struct nvkm_i2c_aux *aux) +{ + AUX_TRACE(aux, "init"); + mutex_lock(&aux->mutex); + aux->enabled = true; + mutex_unlock(&aux->mutex); +} + +void +nvkm_i2c_aux_fini(struct nvkm_i2c_aux *aux) +{ + AUX_TRACE(aux, "fini"); + mutex_lock(&aux->mutex); + aux->enabled = false; + mutex_unlock(&aux->mutex); +} + +int +nvkm_i2c_aux_ctor(const struct nvkm_i2c_aux_func *func, + struct nvkm_i2c_pad *pad, int id, + struct nvkm_i2c_aux *aux) +{ + struct nvkm_device *device = pad->i2c->subdev.device; + + aux->func = func; + aux->pad = pad; + aux->id = id; + mutex_init(&aux->mutex); + list_add_tail(&aux->head, &pad->i2c->aux); + AUX_TRACE(aux, "ctor"); + + snprintf(aux->i2c.name, sizeof(aux->i2c.name), "nvkm-%s-aux-%04x", + dev_name(device->dev), id); + aux->i2c.owner = THIS_MODULE; + aux->i2c.dev.parent = device->dev; + aux->i2c.algo = &nvkm_i2c_aux_i2c_algo; + return i2c_add_adapter(&aux->i2c); +} + +int +nvkm_i2c_aux_new_(const struct nvkm_i2c_aux_func *func, + struct nvkm_i2c_pad *pad, int id, + struct nvkm_i2c_aux **paux) +{ + if (!(*paux = kzalloc(sizeof(**paux), GFP_KERNEL))) + return -ENOMEM; + return nvkm_i2c_aux_ctor(func, pad, id, *paux); +} |