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path: root/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c
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Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c')
-rw-r--r--drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c245
1 files changed, 245 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c b/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c
new file mode 100644
index 000000000000..807a2b67bd64
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/bus.c
@@ -0,0 +1,245 @@
+/*
+ * Copyright 2015 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 <bskeggs@redhat.com>
+ */
+#include "bus.h"
+#include "pad.h"
+
+#include <core/option.h>
+
+/*******************************************************************************
+ * i2c-algo-bit
+ ******************************************************************************/
+static int
+nvkm_i2c_bus_pre_xfer(struct i2c_adapter *adap)
+{
+ struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
+ return nvkm_i2c_bus_acquire(bus);
+}
+
+static void
+nvkm_i2c_bus_post_xfer(struct i2c_adapter *adap)
+{
+ struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
+ return nvkm_i2c_bus_release(bus);
+}
+
+static void
+nvkm_i2c_bus_setscl(void *data, int state)
+{
+ struct nvkm_i2c_bus *bus = data;
+ bus->func->drive_scl(bus, state);
+}
+
+static void
+nvkm_i2c_bus_setsda(void *data, int state)
+{
+ struct nvkm_i2c_bus *bus = data;
+ bus->func->drive_sda(bus, state);
+}
+
+static int
+nvkm_i2c_bus_getscl(void *data)
+{
+ struct nvkm_i2c_bus *bus = data;
+ return bus->func->sense_scl(bus);
+}
+
+static int
+nvkm_i2c_bus_getsda(void *data)
+{
+ struct nvkm_i2c_bus *bus = data;
+ return bus->func->sense_sda(bus);
+}
+
+/*******************************************************************************
+ * !i2c-algo-bit (off-chip i2c bus / hw i2c / internal bit-banging algo)
+ ******************************************************************************/
+static int
+nvkm_i2c_bus_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ struct nvkm_i2c_bus *bus = container_of(adap, typeof(*bus), i2c);
+ int ret;
+
+ ret = nvkm_i2c_bus_acquire(bus);
+ if (ret)
+ return ret;
+
+ ret = bus->func->xfer(bus, msgs, num);
+ nvkm_i2c_bus_release(bus);
+ return ret;
+}
+
+static u32
+nvkm_i2c_bus_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm
+nvkm_i2c_bus_algo = {
+ .master_xfer = nvkm_i2c_bus_xfer,
+ .functionality = nvkm_i2c_bus_func,
+};
+
+/*******************************************************************************
+ * nvkm_i2c_bus base
+ ******************************************************************************/
+void
+nvkm_i2c_bus_init(struct nvkm_i2c_bus *bus)
+{
+ BUS_TRACE(bus, "init");
+ if (bus->func->init)
+ bus->func->init(bus);
+}
+
+void
+nvkm_i2c_bus_release(struct nvkm_i2c_bus *bus)
+{
+ struct nvkm_i2c_pad *pad = bus->pad;
+ BUS_TRACE(bus, "release");
+ nvkm_i2c_pad_release(pad);
+ mutex_unlock(&bus->mutex);
+}
+
+int
+nvkm_i2c_bus_acquire(struct nvkm_i2c_bus *bus)
+{
+ struct nvkm_i2c_pad *pad = bus->pad;
+ int ret;
+ BUS_TRACE(bus, "acquire");
+ mutex_lock(&bus->mutex);
+ ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_I2C);
+ if (ret)
+ mutex_unlock(&bus->mutex);
+ return ret;
+}
+
+int
+nvkm_i2c_bus_probe(struct nvkm_i2c_bus *bus, const char *what,
+ struct nvkm_i2c_bus_probe *info,
+ bool (*match)(struct nvkm_i2c_bus *,
+ struct i2c_board_info *, void *), void *data)
+{
+ int i;
+
+ BUS_DBG(bus, "probing %ss", what);
+ for (i = 0; info[i].dev.addr; i++) {
+ u8 orig_udelay = 0;
+
+ if ((bus->i2c.algo == &i2c_bit_algo) && (info[i].udelay != 0)) {
+ struct i2c_algo_bit_data *algo = bus->i2c.algo_data;
+ BUS_DBG(bus, "%dms delay instead of %dms",
+ info[i].udelay, algo->udelay);
+ orig_udelay = algo->udelay;
+ algo->udelay = info[i].udelay;
+ }
+
+ if (nvkm_probe_i2c(&bus->i2c, info[i].dev.addr) &&
+ (!match || match(bus, &info[i].dev, data))) {
+ BUS_DBG(bus, "detected %s: %s",
+ what, info[i].dev.type);
+ return i;
+ }
+
+ if (orig_udelay) {
+ struct i2c_algo_bit_data *algo = bus->i2c.algo_data;
+ algo->udelay = orig_udelay;
+ }
+ }
+
+ BUS_DBG(bus, "no devices found.");
+ return -ENODEV;
+}
+
+void
+nvkm_i2c_bus_del(struct nvkm_i2c_bus **pbus)
+{
+ struct nvkm_i2c_bus *bus = *pbus;
+ if (bus && !WARN_ON(!bus->func)) {
+ BUS_TRACE(bus, "dtor");
+ list_del(&bus->head);
+ i2c_del_adapter(&bus->i2c);
+ kfree(bus->i2c.algo_data);
+ kfree(*pbus);
+ *pbus = NULL;
+ }
+}
+
+int
+nvkm_i2c_bus_ctor(const struct nvkm_i2c_bus_func *func,
+ struct nvkm_i2c_pad *pad, int id,
+ struct nvkm_i2c_bus *bus)
+{
+ struct nvkm_device *device = pad->i2c->subdev.device;
+ struct i2c_algo_bit_data *bit;
+#ifndef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT
+ const bool internal = false;
+#else
+ const bool internal = true;
+#endif
+ int ret;
+
+ bus->func = func;
+ bus->pad = pad;
+ bus->id = id;
+ mutex_init(&bus->mutex);
+ list_add_tail(&bus->head, &pad->i2c->bus);
+ BUS_TRACE(bus, "ctor");
+
+ snprintf(bus->i2c.name, sizeof(bus->i2c.name), "nvkm-%s-bus-%04x",
+ dev_name(device->dev), id);
+ bus->i2c.owner = THIS_MODULE;
+ bus->i2c.dev.parent = device->dev;
+
+ if ( bus->func->drive_scl &&
+ !nvkm_boolopt(device->cfgopt, "NvI2C", internal)) {
+ if (!(bit = kzalloc(sizeof(*bit), GFP_KERNEL)))
+ return -ENOMEM;
+ bit->udelay = 10;
+ bit->timeout = usecs_to_jiffies(2200);
+ bit->data = bus;
+ bit->pre_xfer = nvkm_i2c_bus_pre_xfer;
+ bit->post_xfer = nvkm_i2c_bus_post_xfer;
+ bit->setscl = nvkm_i2c_bus_setscl;
+ bit->setsda = nvkm_i2c_bus_setsda;
+ bit->getscl = nvkm_i2c_bus_getscl;
+ bit->getsda = nvkm_i2c_bus_getsda;
+ bus->i2c.algo_data = bit;
+ ret = i2c_bit_add_bus(&bus->i2c);
+ } else {
+ bus->i2c.algo = &nvkm_i2c_bus_algo;
+ ret = i2c_add_adapter(&bus->i2c);
+ }
+
+ return ret;
+}
+
+int
+nvkm_i2c_bus_new_(const struct nvkm_i2c_bus_func *func,
+ struct nvkm_i2c_pad *pad, int id,
+ struct nvkm_i2c_bus **pbus)
+{
+ if (!(*pbus = kzalloc(sizeof(**pbus), GFP_KERNEL)))
+ return -ENOMEM;
+ return nvkm_i2c_bus_ctor(func, pad, id, *pbus);
+}