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
  27 struct nv4e_i2c_bus {
  28         struct nvkm_i2c_bus base;
  29         u32 addr;
  30 };
  31
  32 static void
  33 nv4e_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
  40 static void
  41 nv4e_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
  48 static int
  49 nv4e_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
  56 static int
  57 nv4e_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
  64 static const struct nvkm_i2c_bus_func
  65 nv4e_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
  73 int
  74 nv4e_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 }