1 /*
2 * Copyright 2015 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 busions 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 <bskeggs@redhat.com>
23 */
24 #define nv04_i2c_bus(p) container_of((p), struct nv04_i2c_bus, base)
25 #include "bus.h"
26
27 #include <subdev/vga.h>
28
29 struct nv04_i2c_bus {
30 struct nvkm_i2c_bus base;
31 u8 drive;
32 u8 sense;
33 };
34
35 static void
nv04_i2c_bus_drive_scl(struct nvkm_i2c_bus * base,int state)36 nv04_i2c_bus_drive_scl(struct nvkm_i2c_bus *base, int state)
37 {
38 struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
39 struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
40 u8 val = nvkm_rdvgac(device, 0, bus->drive);
41 if (state) val |= 0x20;
42 else val &= 0xdf;
43 nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
44 }
45
46 static void
nv04_i2c_bus_drive_sda(struct nvkm_i2c_bus * base,int state)47 nv04_i2c_bus_drive_sda(struct nvkm_i2c_bus *base, int state)
48 {
49 struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
50 struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
51 u8 val = nvkm_rdvgac(device, 0, bus->drive);
52 if (state) val |= 0x10;
53 else val &= 0xef;
54 nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
55 }
56
57 static int
nv04_i2c_bus_sense_scl(struct nvkm_i2c_bus * base)58 nv04_i2c_bus_sense_scl(struct nvkm_i2c_bus *base)
59 {
60 struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
61 struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
62 return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x04);
63 }
64
65 static int
nv04_i2c_bus_sense_sda(struct nvkm_i2c_bus * base)66 nv04_i2c_bus_sense_sda(struct nvkm_i2c_bus *base)
67 {
68 struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
69 struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
70 return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x08);
71 }
72
73 static const struct nvkm_i2c_bus_func
74 nv04_i2c_bus_func = {
75 .drive_scl = nv04_i2c_bus_drive_scl,
76 .drive_sda = nv04_i2c_bus_drive_sda,
77 .sense_scl = nv04_i2c_bus_sense_scl,
78 .sense_sda = nv04_i2c_bus_sense_sda,
79 .xfer = nvkm_i2c_bit_xfer,
80 };
81
82 int
nv04_i2c_bus_new(struct nvkm_i2c_pad * pad,int id,u8 drive,u8 sense,struct nvkm_i2c_bus ** pbus)83 nv04_i2c_bus_new(struct nvkm_i2c_pad *pad, int id, u8 drive, u8 sense,
84 struct nvkm_i2c_bus **pbus)
85 {
86 struct nv04_i2c_bus *bus;
87
88 if (!(bus = kzalloc(sizeof(*bus), GFP_KERNEL)))
89 return -ENOMEM;
90 *pbus = &bus->base;
91
92 nvkm_i2c_bus_ctor(&nv04_i2c_bus_func, pad, id, &bus->base);
93 bus->drive = drive;
94 bus->sense = sense;
95 return 0;
96 }
97