busnv50.c

  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 nv50_i2c_bus(p) container_of((p), struct nv50_i2c_bus, base)
 25#include "bus.h"
 26
 27#include <subdev/vga.h>
 28
 29struct nv50_i2c_bus {
 30	struct nvkm_i2c_bus base;
 31	u32 addr;
 32	u32 data;
 33};
 34
 35static void
 36nv50_i2c_bus_drive_scl(struct nvkm_i2c_bus *base, int state)
 37{
 38	struct nv50_i2c_bus *bus = nv50_i2c_bus(base);
 39	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
 40	if (state) bus->data |= 0x01;
 41	else	   bus->data &= 0xfe;
 42	nvkm_wr32(device, bus->addr, bus->data);
 43}
 44
 45static void
 46nv50_i2c_bus_drive_sda(struct nvkm_i2c_bus *base, int state)
 47{
 48	struct nv50_i2c_bus *bus = nv50_i2c_bus(base);
 49	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
 50	if (state) bus->data |= 0x02;
 51	else	   bus->data &= 0xfd;
 52	nvkm_wr32(device, bus->addr, bus->data);
 53}
 54
 55static int
 56nv50_i2c_bus_sense_scl(struct nvkm_i2c_bus *base)
 57{
 58	struct nv50_i2c_bus *bus = nv50_i2c_bus(base);
 59	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
 60	return !!(nvkm_rd32(device, bus->addr) & 0x00000001);
 61}
 62
 63static int
 64nv50_i2c_bus_sense_sda(struct nvkm_i2c_bus *base)
 65{
 66	struct nv50_i2c_bus *bus = nv50_i2c_bus(base);
 67	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
 68	return !!(nvkm_rd32(device, bus->addr) & 0x00000002);
 69}
 70
 71static void
 72nv50_i2c_bus_init(struct nvkm_i2c_bus *base)
 73{
 74	struct nv50_i2c_bus *bus = nv50_i2c_bus(base);
 75	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
 76	nvkm_wr32(device, bus->addr, (bus->data = 0x00000007));
 77}
 78
 79static const struct nvkm_i2c_bus_func
 80nv50_i2c_bus_func = {
 81	.init = nv50_i2c_bus_init,
 82	.drive_scl = nv50_i2c_bus_drive_scl,
 83	.drive_sda = nv50_i2c_bus_drive_sda,
 84	.sense_scl = nv50_i2c_bus_sense_scl,
 85	.sense_sda = nv50_i2c_bus_sense_sda,
 86	.xfer = nvkm_i2c_bit_xfer,
 87};
 88
 89int
 90nv50_i2c_bus_new(struct nvkm_i2c_pad *pad, int id, u8 drive,
 91		 struct nvkm_i2c_bus **pbus)
 92{
 93	static const u32 addr[] = {
 94		0x00e138, 0x00e150, 0x00e168, 0x00e180,
 95		0x00e254, 0x00e274, 0x00e764, 0x00e780,
 96		0x00e79c, 0x00e7b8
 97	};
 98	struct nv50_i2c_bus *bus;
 99
100	if (drive >= ARRAY_SIZE(addr)) {
101		nvkm_warn(&pad->i2c->subdev, "bus %d unknown\n", drive);
102		return -ENODEV;
103	}
104
105	if (!(bus = kzalloc(sizeof(*bus), GFP_KERNEL)))
106		return -ENOMEM;
107	*pbus = &bus->base;
108
109	nvkm_i2c_bus_ctor(&nv50_i2c_bus_func, pad, id, &bus->base);
110	bus->addr = addr[drive];
111	bus->data = 0x00000007;
112	return 0;
113}