diff options
Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c')
-rw-r--r-- | drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c b/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c new file mode 100644 index 000000000..443c031b9 --- /dev/null +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c @@ -0,0 +1,98 @@ +/* + * Copyright 2013 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: Ben Skeggs + */ +#include <subdev/volt.h> +#include <subdev/bios.h> +#include <subdev/bios/gpio.h> +#include <subdev/gpio.h> +#include "priv.h" + +static const u8 tags[] = { + DCB_GPIO_VID0, DCB_GPIO_VID1, DCB_GPIO_VID2, DCB_GPIO_VID3, + DCB_GPIO_VID4, DCB_GPIO_VID5, DCB_GPIO_VID6, DCB_GPIO_VID7, +}; + +int +nvkm_voltgpio_get(struct nvkm_volt *volt) +{ + struct nvkm_gpio *gpio = volt->subdev.device->gpio; + u8 vid = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(tags); i++) { + if (volt->vid_mask & (1 << i)) { + int ret = nvkm_gpio_get(gpio, 0, tags[i], 0xff); + if (ret < 0) + return ret; + vid |= ret << i; + } + } + + return vid; +} + +int +nvkm_voltgpio_set(struct nvkm_volt *volt, u8 vid) +{ + struct nvkm_gpio *gpio = volt->subdev.device->gpio; + int i; + + for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) { + if (volt->vid_mask & (1 << i)) { + int ret = nvkm_gpio_set(gpio, 0, tags[i], 0xff, vid & 1); + if (ret < 0) + return ret; + } + } + + return 0; +} + +int +nvkm_voltgpio_init(struct nvkm_volt *volt) +{ + struct nvkm_subdev *subdev = &volt->subdev; + struct nvkm_gpio *gpio = subdev->device->gpio; + struct dcb_gpio_func func; + int i; + + /* check we have gpio function info for each vid bit. on some + * boards (ie. nvs295) the vid mask has more bits than there + * are valid gpio functions... from traces, nvidia appear to + * just touch the existing ones, so let's mask off the invalid + * bits and continue with life + */ + for (i = 0; i < ARRAY_SIZE(tags); i++) { + if (volt->vid_mask & (1 << i)) { + int ret = nvkm_gpio_find(gpio, 0, tags[i], 0xff, &func); + if (ret) { + if (ret != -ENOENT) + return ret; + nvkm_debug(subdev, "VID bit %d has no GPIO\n", i); + volt->vid_mask &= ~(1 << i); + } + } + } + + return 0; +} |