summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c')
-rw-r--r--drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c96
1 files changed, 96 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 000000000000..755fa91bcd09
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c
@@ -0,0 +1,96 @@
+/*
+ * 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/gpio.h>
+#include <subdev/bios/gpio.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
+nouveau_voltgpio_get(struct nouveau_volt *volt)
+{
+ struct nouveau_gpio *gpio = nouveau_gpio(volt);
+ u8 vid = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tags); i++) {
+ if (volt->vid_mask & (1 << i)) {
+ int ret = gpio->get(gpio, 0, tags[i], 0xff);
+ if (ret < 0)
+ return ret;
+ vid |= ret << i;
+ }
+ }
+
+ return vid;
+}
+
+int
+nouveau_voltgpio_set(struct nouveau_volt *volt, u8 vid)
+{
+ struct nouveau_gpio *gpio = nouveau_gpio(volt);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) {
+ if (volt->vid_mask & (1 << i)) {
+ int ret = gpio->set(gpio, 0, tags[i], 0xff, vid & 1);
+ if (ret < 0)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+int
+nouveau_voltgpio_init(struct nouveau_volt *volt)
+{
+ struct nouveau_gpio *gpio = nouveau_gpio(volt);
+ 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 = gpio->find(gpio, 0, tags[i], 0xff, &func);
+ if (ret) {
+ if (ret != -ENOENT)
+ return ret;
+ nv_debug(volt, "VID bit %d has no GPIO\n", i);
+ volt->vid_mask &= ~(1 << i);
+ }
+ }
+ }
+
+ return 0;
+}