xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/nouveau/nvkm/subdev/i2c/nouveau_nvkm_subdev_i2c_busnv04.c (revision 41ec02673d281bbb3d38e6c78504ce6e30c228c1)
1 /*	$NetBSD: nouveau_nvkm_subdev_i2c_busnv04.c,v 1.3 2021/12/18 23:45:40 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2015 Red Hat Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial busions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: Ben Skeggs <bskeggs@redhat.com>
25  */
26 #include <sys/cdefs.h>
27 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_i2c_busnv04.c,v 1.3 2021/12/18 23:45:40 riastradh Exp $");
28 
29 #define nv04_i2c_bus(p) container_of((p), struct nv04_i2c_bus, base)
30 #include "bus.h"
31 
32 #include <subdev/vga.h>
33 
34 struct nv04_i2c_bus {
35 	struct nvkm_i2c_bus base;
36 	u8 drive;
37 	u8 sense;
38 };
39 
40 static void
nv04_i2c_bus_drive_scl(struct nvkm_i2c_bus * base,int state)41 nv04_i2c_bus_drive_scl(struct nvkm_i2c_bus *base, int state)
42 {
43 	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
44 	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
45 	u8 val = nvkm_rdvgac(device, 0, bus->drive);
46 	if (state) val |= 0x20;
47 	else	   val &= 0xdf;
48 	nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
49 }
50 
51 static void
nv04_i2c_bus_drive_sda(struct nvkm_i2c_bus * base,int state)52 nv04_i2c_bus_drive_sda(struct nvkm_i2c_bus *base, int state)
53 {
54 	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
55 	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
56 	u8 val = nvkm_rdvgac(device, 0, bus->drive);
57 	if (state) val |= 0x10;
58 	else	   val &= 0xef;
59 	nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
60 }
61 
62 static int
nv04_i2c_bus_sense_scl(struct nvkm_i2c_bus * base)63 nv04_i2c_bus_sense_scl(struct nvkm_i2c_bus *base)
64 {
65 	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
66 	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
67 	return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x04);
68 }
69 
70 static int
nv04_i2c_bus_sense_sda(struct nvkm_i2c_bus * base)71 nv04_i2c_bus_sense_sda(struct nvkm_i2c_bus *base)
72 {
73 	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
74 	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
75 	return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x08);
76 }
77 
78 static const struct nvkm_i2c_bus_func
79 nv04_i2c_bus_func = {
80 	.drive_scl = nv04_i2c_bus_drive_scl,
81 	.drive_sda = nv04_i2c_bus_drive_sda,
82 	.sense_scl = nv04_i2c_bus_sense_scl,
83 	.sense_sda = nv04_i2c_bus_sense_sda,
84 	.xfer = nvkm_i2c_bit_xfer,
85 };
86 
87 int
nv04_i2c_bus_new(struct nvkm_i2c_pad * pad,int id,u8 drive,u8 sense,struct nvkm_i2c_bus ** pbus)88 nv04_i2c_bus_new(struct nvkm_i2c_pad *pad, int id, u8 drive, u8 sense,
89 		 struct nvkm_i2c_bus **pbus)
90 {
91 	struct nv04_i2c_bus *bus;
92 
93 	if (!(bus = kzalloc(sizeof(*bus), GFP_KERNEL)))
94 		return -ENOMEM;
95 	*pbus = &bus->base;
96 
97 	nvkm_i2c_bus_ctor(&nv04_i2c_bus_func, pad, id, &bus->base);
98 	bus->drive = drive;
99 	bus->sense = sense;
100 	return 0;
101 }
102