1 files changed, 395 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c
new file mode 100644
index 000000000000..31a676376d73
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c
@@ -0,0 +1,395 @@
+/*
+ * Copyright 2007-8 Advanced Micro Devices, Inc.
+ * Copyright 2008 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: Dave Airlie
+ *          Alex Deucher
+ */
+#include <linux/export.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_edid.h>
+#include <drm/amdgpu_drm.h>
+#include "amdgpu.h"
+#include "amdgpu_i2c.h"
+#include "amdgpu_atombios.h"
+#include "atom.h"
+#include "atombios_dp.h"
+#include "atombios_i2c.h"
+
+/* bit banging i2c */
+static int amdgpu_i2c_pre_xfer(struct i2c_adapter *i2c_adap)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t temp;
+
+	mutex_lock(&i2c->mutex);
+
+	/* switch the pads to ddc mode */
+	if (rec->hw_capable) {
+		temp = RREG32(rec->mask_clk_reg);
+		temp &= ~(1 << 16);
+		WREG32(rec->mask_clk_reg, temp);
+	}
+
+	/* clear the output pin values */
+	temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask;
+	WREG32(rec->a_clk_reg, temp);
+
+	temp = RREG32(rec->a_data_reg) & ~rec->a_data_mask;
+	WREG32(rec->a_data_reg, temp);
+
+	/* set the pins to input */
+	temp = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
+	WREG32(rec->en_clk_reg, temp);
+
+	temp = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
+	WREG32(rec->en_data_reg, temp);
+
+	/* mask the gpio pins for software use */
+	temp = RREG32(rec->mask_clk_reg) | rec->mask_clk_mask;
+	WREG32(rec->mask_clk_reg, temp);
+	temp = RREG32(rec->mask_clk_reg);
+
+	temp = RREG32(rec->mask_data_reg) | rec->mask_data_mask;
+	WREG32(rec->mask_data_reg, temp);
+	temp = RREG32(rec->mask_data_reg);
+
+	return 0;
+}
+
+static void amdgpu_i2c_post_xfer(struct i2c_adapter *i2c_adap)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t temp;
+
+	/* unmask the gpio pins for software use */
+	temp = RREG32(rec->mask_clk_reg) & ~rec->mask_clk_mask;
+	WREG32(rec->mask_clk_reg, temp);
+	temp = RREG32(rec->mask_clk_reg);
+
+	temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask;
+	WREG32(rec->mask_data_reg, temp);
+	temp = RREG32(rec->mask_data_reg);
+
+	mutex_unlock(&i2c->mutex);
+}
+
+static int amdgpu_i2c_get_clock(void *i2c_priv)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_priv;
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t val;
+
+	/* read the value off the pin */
+	val = RREG32(rec->y_clk_reg);
+	val &= rec->y_clk_mask;
+
+	return (val != 0);
+}
+
+
+static int amdgpu_i2c_get_data(void *i2c_priv)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_priv;
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t val;
+
+	/* read the value off the pin */
+	val = RREG32(rec->y_data_reg);
+	val &= rec->y_data_mask;
+
+	return (val != 0);
+}
+
+static void amdgpu_i2c_set_clock(void *i2c_priv, int clock)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_priv;
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t val;
+
+	/* set pin direction */
+	val = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
+	val |= clock ? 0 : rec->en_clk_mask;
+	WREG32(rec->en_clk_reg, val);
+}
+
+static void amdgpu_i2c_set_data(void *i2c_priv, int data)
+{
+	struct amdgpu_i2c_chan *i2c = i2c_priv;
+	struct amdgpu_device *adev = i2c->dev->dev_private;
+	struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
+	uint32_t val;
+
+	/* set pin direction */
+	val = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
+	val |= data ? 0 : rec->en_data_mask;
+	WREG32(rec->en_data_reg, val);
+}
+
+static const struct i2c_algorithm amdgpu_atombios_i2c_algo = {
+	.master_xfer = amdgpu_atombios_i2c_xfer,
+	.functionality = amdgpu_atombios_i2c_func,
+};
+
+struct amdgpu_i2c_chan *amdgpu_i2c_create(struct drm_device *dev,
+					    struct amdgpu_i2c_bus_rec *rec,
+					    const char *name)
+{
+	struct amdgpu_i2c_chan *i2c;
+	int ret;
+
+	/* don't add the mm_i2c bus unless hw_i2c is enabled */
+	if (rec->mm_i2c && (amdgpu_hw_i2c == 0))
+		return NULL;
+
+	i2c = kzalloc(sizeof(struct amdgpu_i2c_chan), GFP_KERNEL);
+	if (i2c == NULL)
+		return NULL;
+
+	i2c->rec = *rec;
+	i2c->adapter.owner = THIS_MODULE;
+	i2c->adapter.class = I2C_CLASS_DDC;
+	i2c->adapter.dev.parent = &dev->pdev->dev;
+	i2c->dev = dev;
+	i2c_set_adapdata(&i2c->adapter, i2c);
+	mutex_init(&i2c->mutex);
+	if (rec->hw_capable &&
+	    amdgpu_hw_i2c) {
+		/* hw i2c using atom */
+		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
+			 "AMDGPU i2c hw bus %s", name);
+		i2c->adapter.algo = &amdgpu_atombios_i2c_algo;
+		ret = i2c_add_adapter(&i2c->adapter);
+		if (ret) {
+			DRM_ERROR("Failed to register hw i2c %s\n", name);
+			goto out_free;
+		}
+	} else {
+		/* set the amdgpu bit adapter */
+		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
+			 "AMDGPU i2c bit bus %s", name);
+		i2c->adapter.algo_data = &i2c->bit;
+		i2c->bit.pre_xfer = amdgpu_i2c_pre_xfer;
+		i2c->bit.post_xfer = amdgpu_i2c_post_xfer;
+		i2c->bit.setsda = amdgpu_i2c_set_data;
+		i2c->bit.setscl = amdgpu_i2c_set_clock;
+		i2c->bit.getsda = amdgpu_i2c_get_data;
+		i2c->bit.getscl = amdgpu_i2c_get_clock;
+		i2c->bit.udelay = 10;
+		i2c->bit.timeout = usecs_to_jiffies(2200);	/* from VESA */
+		i2c->bit.data = i2c;
+		ret = i2c_bit_add_bus(&i2c->adapter);
+		if (ret) {
+			DRM_ERROR("Failed to register bit i2c %s\n", name);
+			goto out_free;
+		}
+	}
+
+	return i2c;
+out_free:
+	kfree(i2c);
+	return NULL;
+
+}
+
+void amdgpu_i2c_destroy(struct amdgpu_i2c_chan *i2c)
+{
+	if (!i2c)
+		return;
+	i2c_del_adapter(&i2c->adapter);
+	kfree(i2c);
+}
+
+/* Add the default buses */
+void amdgpu_i2c_init(struct amdgpu_device *adev)
+{
+	if (amdgpu_hw_i2c)
+		DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");
+
+	if (adev->is_atom_bios)
+		amdgpu_atombios_i2c_init(adev);
+}
+
+/* remove all the buses */
+void amdgpu_i2c_fini(struct amdgpu_device *adev)
+{
+	int i;
+
+	for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
+		if (adev->i2c_bus[i]) {
+			amdgpu_i2c_destroy(adev->i2c_bus[i]);
+			adev->i2c_bus[i] = NULL;
+		}
+	}
+}
+
+/* Add additional buses */
+void amdgpu_i2c_add(struct amdgpu_device *adev,
+		     struct amdgpu_i2c_bus_rec *rec,
+		     const char *name)
+{
+	struct drm_device *dev = adev->ddev;
+	int i;
+
+	for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
+		if (!adev->i2c_bus[i]) {
+			adev->i2c_bus[i] = amdgpu_i2c_create(dev, rec, name);
+			return;
+		}
+	}
+}
+
+/* looks up bus based on id */
+struct amdgpu_i2c_chan *
+amdgpu_i2c_lookup(struct amdgpu_device *adev,
+		   struct amdgpu_i2c_bus_rec *i2c_bus)
+{
+	int i;
+
+	for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
+		if (adev->i2c_bus[i] &&
+		    (adev->i2c_bus[i]->rec.i2c_id == i2c_bus->i2c_id)) {
+			return adev->i2c_bus[i];
+		}
+	}
+	return NULL;
+}
+
+static void amdgpu_i2c_get_byte(struct amdgpu_i2c_chan *i2c_bus,
+				 u8 slave_addr,
+				 u8 addr,
+				 u8 *val)
+{
+	u8 out_buf[2];
+	u8 in_buf[2];
+	struct i2c_msg msgs[] = {
+		{
+			.addr = slave_addr,
+			.flags = 0,
+			.len = 1,
+			.buf = out_buf,
+		},
+		{
+			.addr = slave_addr,
+			.flags = I2C_M_RD,
+			.len = 1,
+			.buf = in_buf,
+		}
+	};
+
+	out_buf[0] = addr;
+	out_buf[1] = 0;
+
+	if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) {
+		*val = in_buf[0];
+		DRM_DEBUG("val = 0x%02x\n", *val);
+	} else {
+		DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n",
+			  addr, *val);
+	}
+}
+
+static void amdgpu_i2c_put_byte(struct amdgpu_i2c_chan *i2c_bus,
+				 u8 slave_addr,
+				 u8 addr,
+				 u8 val)
+{
+	uint8_t out_buf[2];
+	struct i2c_msg msg = {
+		.addr = slave_addr,
+		.flags = 0,
+		.len = 2,
+		.buf = out_buf,
+	};
+
+	out_buf[0] = addr;
+	out_buf[1] = val;
+
+	if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1)
+		DRM_DEBUG("i2c 0x%02x 0x%02x write failed\n",
+			  addr, val);
+}
+
+/* ddc router switching */
+void
+amdgpu_i2c_router_select_ddc_port(struct amdgpu_connector *amdgpu_connector)
+{
+	u8 val;
+
+	if (!amdgpu_connector->router.ddc_valid)
+		return;
+
+	if (!amdgpu_connector->router_bus)
+		return;
+
+	amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x3, &val);
+	val &= ~amdgpu_connector->router.ddc_mux_control_pin;
+	amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x3, val);
+	amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x1, &val);
+	val &= ~amdgpu_connector->router.ddc_mux_control_pin;
+	val |= amdgpu_connector->router.ddc_mux_state;
+	amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x1, val);
+}
+
+/* clock/data router switching */
+void
+amdgpu_i2c_router_select_cd_port(struct amdgpu_connector *amdgpu_connector)
+{
+	u8 val;
+
+	if (!amdgpu_connector->router.cd_valid)
+		return;
+
+	if (!amdgpu_connector->router_bus)
+		return;
+
+	amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x3, &val);
+	val &= ~amdgpu_connector->router.cd_mux_control_pin;
+	amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x3, val);
+	amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x1, &val);
+	val &= ~amdgpu_connector->router.cd_mux_control_pin;
+	val |= amdgpu_connector->router.cd_mux_state;
+	amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
+			    amdgpu_connector->router.i2c_addr,
+			    0x1, val);
+}