LXR linux/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/busnv4e.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 nv4e_i2c_bus(p) container_of((p), struct nv4e_i2c_bus, base)
  25#include "bus.h"
  26
  27struct nv4e_i2c_bus {
  28        struct nvkm_i2c_bus base;
  29        u32 addr;
  30};
  31
  32static void
  33nv4e_i2c_bus_drive_scl(struct nvkm_i2c_bus *base, int state)
  34{
  35        struct nv4e_i2c_bus *bus = nv4e_i2c_bus(base);
  36        struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
  37        nvkm_mask(device, bus->addr, 0x2f, state ? 0x21 : 0x01);
  38}
  39
  40static void
  41nv4e_i2c_bus_drive_sda(struct nvkm_i2c_bus *base, int state)
  42{
  43        struct nv4e_i2c_bus *bus = nv4e_i2c_bus(base);
  44        struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
  45        nvkm_mask(device, bus->addr, 0x1f, state ? 0x11 : 0x01);
  46}
  47
  48static int
  49nv4e_i2c_bus_sense_scl(struct nvkm_i2c_bus *base)
  50{
  51        struct nv4e_i2c_bus *bus = nv4e_i2c_bus(base);
  52        struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
  53        return !!(nvkm_rd32(device, bus->addr) & 0x00040000);
  54}
  55
  56static int
  57nv4e_i2c_bus_sense_sda(struct nvkm_i2c_bus *base)
  58{
  59        struct nv4e_i2c_bus *bus = nv4e_i2c_bus(base);
  60        struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
  61        return !!(nvkm_rd32(device, bus->addr) & 0x00080000);
  62}
  63
  64static const struct nvkm_i2c_bus_func
  65nv4e_i2c_bus_func = {
  66        .drive_scl = nv4e_i2c_bus_drive_scl,
  67        .drive_sda = nv4e_i2c_bus_drive_sda,
  68        .sense_scl = nv4e_i2c_bus_sense_scl,
  69        .sense_sda = nv4e_i2c_bus_sense_sda,
  70        .xfer = nvkm_i2c_bit_xfer,
  71};
  72
  73int
  74nv4e_i2c_bus_new(struct nvkm_i2c_pad *pad, int id, u8 drive,
  75                 struct nvkm_i2c_bus **pbus)
  76{
  77        struct nv4e_i2c_bus *bus;
  78
  79        if (!(bus = kzalloc(sizeof(*bus), GFP_KERNEL)))
  80                return -ENOMEM;
  81        *pbus = &bus->base;
  82
  83        nvkm_i2c_bus_ctor(&nv4e_i2c_bus_func, pad, id, &bus->base);
  84        bus->addr = 0x600800 + drive;
  85        return 0;
  86}
  87