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
27static int
28nvkm_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 = (remaining > 16) ? 16 : remaining;
44			u8 cmd;
45
46			if (msg->flags & I2C_M_RD)
47				cmd = 1;
48			else
49				cmd = 0;
50
51			if (mcnt || remaining > 16)
52				cmd |= 4; /* MOT */
53
54			ret = aux->func->xfer(aux, true, cmd, msg->addr, ptr, cnt);
55			if (ret < 0) {
56				nvkm_i2c_aux_release(aux);
57				return ret;
58			}
59
60			ptr += cnt;
61			remaining -= cnt;
62		}
63
64		msg++;
65	}
66
67	nvkm_i2c_aux_release(aux);
68	return num;
69}
70
71static u32
72nvkm_i2c_aux_i2c_func(struct i2c_adapter *adap)
73{
74	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
75}
76
77const struct i2c_algorithm
78nvkm_i2c_aux_i2c_algo = {
79	.master_xfer = nvkm_i2c_aux_i2c_xfer,
80	.functionality = nvkm_i2c_aux_i2c_func
81};
82
83void
84nvkm_i2c_aux_monitor(struct nvkm_i2c_aux *aux, bool monitor)
85{
86	struct nvkm_i2c_pad *pad = aux->pad;
87	AUX_TRACE(aux, "monitor: %s", monitor ? "yes" : "no");
88	if (monitor)
89		nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_AUX);
90	else
91		nvkm_i2c_pad_mode(pad, NVKM_I2C_PAD_OFF);
92}
93
94void
95nvkm_i2c_aux_release(struct nvkm_i2c_aux *aux)
96{
97	struct nvkm_i2c_pad *pad = aux->pad;
98	AUX_TRACE(aux, "release");
99	nvkm_i2c_pad_release(pad);
100	mutex_unlock(&aux->mutex);
101}
102
103int
104nvkm_i2c_aux_acquire(struct nvkm_i2c_aux *aux)
105{
106	struct nvkm_i2c_pad *pad = aux->pad;
107	int ret;
108	AUX_TRACE(aux, "acquire");
109	mutex_lock(&aux->mutex);
110	ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_AUX);
111	if (ret)
112		mutex_unlock(&aux->mutex);
113	return ret;
114}
115
116int
117nvkm_i2c_aux_xfer(struct nvkm_i2c_aux *aux, bool retry, u8 type,
118		  u32 addr, u8 *data, u8 size)
119{
120	return aux->func->xfer(aux, retry, type, addr, data, size);
121}
122
123int
124nvkm_i2c_aux_lnk_ctl(struct nvkm_i2c_aux *aux, int nr, int bw, bool ef)
125{
126	if (aux->func->lnk_ctl)
127		return aux->func->lnk_ctl(aux, nr, bw, ef);
128	return -ENODEV;
129}
130
131void
132nvkm_i2c_aux_del(struct nvkm_i2c_aux **paux)
133{
134	struct nvkm_i2c_aux *aux = *paux;
135	if (aux && !WARN_ON(!aux->func)) {
136		AUX_TRACE(aux, "dtor");
137		list_del(&aux->head);
138		i2c_del_adapter(&aux->i2c);
139		kfree(*paux);
140		*paux = NULL;
141	}
142}
143
144int
145nvkm_i2c_aux_ctor(const struct nvkm_i2c_aux_func *func,
146		  struct nvkm_i2c_pad *pad, int id,
147		  struct nvkm_i2c_aux *aux)
148{
149	struct nvkm_device *device = pad->i2c->subdev.device;
150
151	aux->func = func;
152	aux->pad = pad;
153	aux->id = id;
154	mutex_init(&aux->mutex);
155	list_add_tail(&aux->head, &pad->i2c->aux);
156	AUX_TRACE(aux, "ctor");
157
158	snprintf(aux->i2c.name, sizeof(aux->i2c.name), "nvkm-%s-aux-%04x",
159		 dev_name(device->dev), id);
160	aux->i2c.owner = THIS_MODULE;
161	aux->i2c.dev.parent = device->dev;
162	aux->i2c.algo = &nvkm_i2c_aux_i2c_algo;
163	return i2c_add_adapter(&aux->i2c);
164}
165
166int
167nvkm_i2c_aux_new_(const struct nvkm_i2c_aux_func *func,
168		  struct nvkm_i2c_pad *pad, int id,
169		  struct nvkm_i2c_aux **paux)
170{
171	if (!(*paux = kzalloc(sizeof(**paux), GFP_KERNEL)))
172		return -ENOMEM;
173	return nvkm_i2c_aux_ctor(func, pad, id, *paux);
174}
175