@@ -217,6 +217,18 @@ EDID Helper Functions Reference
.. kernel-doc:: drivers/gpu/drm/drm_edid.c
:export:
+SCDC Helper Functions Reference
+===============================
+
+.. kernel-doc:: drivers/gpu/drm/drm_scdc_helper.c
+ :doc: scdc helpers
+
+.. kernel-doc:: include/drm/drm_scdc_helper.h
+ :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_scdc_helper.c
+ :export:
+
Rectangle Utilities Reference
=============================
@@ -31,7 +31,8 @@ drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o
drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \
drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \
drm_kms_helper_common.o drm_dp_dual_mode_helper.o \
- drm_simple_kms_helper.o drm_modeset_helper.o
+ drm_simple_kms_helper.o drm_modeset_helper.o \
+ drm_scdc_helper.o
drm_kms_helper-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o
new file mode 100644
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2015 NVIDIA Corporation. All rights reserved.
+ *
+ * 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, sub license,
+ * 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#include <linux/slab.h>
+
+#include <drm/drm_scdc_helper.h>
+
+/**
+ * DOC: scdc helpers
+ *
+ * Status and Control Data Channel (SCDC) is a mechanism introduced by the
+ * HDMI 2.0 specification. It is a point-to-point protocol that allows the
+ * HDMI source and HDMI sink to exchange data. The same I2C interface that
+ * is used to access EDID serves as the transport mechanism for SCDC.
+ */
+
+#define SCDC_I2C_SLAVE_ADDRESS 0x54
+
+/**
+ * drm_scdc_read - read a block of data from SCDC
+ * @adapter: I2C controller
+ * @offset: start offset of block to read
+ * @buffer: return location for the block to read
+ * @size: size of the block to read
+ *
+ * Reads a block of data from SCDC, starting at a given offset.
+ *
+ * Returns:
+ * 0 on success, negative error code on failure.
+ */
+ssize_t drm_scdc_read(struct i2c_adapter *adapter, u8 offset, void *buffer,
+ size_t size)
+{
+ int ret;
+ struct i2c_msg msgs[2] = {
+ {
+ .addr = SCDC_I2C_SLAVE_ADDRESS,
+ .flags = 0,
+ .len = 1,
+ .buf = &offset,
+ }, {
+ .addr = SCDC_I2C_SLAVE_ADDRESS,
+ .flags = I2C_M_RD,
+ .len = size,
+ .buf = buffer,
+ }
+ };
+
+ ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ return ret;
+ if (ret != ARRAY_SIZE(msgs))
+ return -EPROTO;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_scdc_read);
+
+/**
+ * drm_scdc_write - write a block of data to SCDC
+ * @adapter: I2C controller
+ * @offset: start offset of block to write
+ * @buffer: block of data to write
+ * @size: size of the block to write
+ *
+ * Writes a block of data to SCDC, starting at a given offset.
+ *
+ * Returns:
+ * 0 on success, negative error code on failure.
+ */
+ssize_t drm_scdc_write(struct i2c_adapter *adapter, u8 offset,
+ const void *buffer, size_t size)
+{
+ struct i2c_msg msg = {
+ .addr = SCDC_I2C_SLAVE_ADDRESS,
+ .flags = 0,
+ .len = 1 + size,
+ .buf = NULL,
+ };
+ void *data;
+ int err;
+
+ data = kmalloc(1 + size, GFP_TEMPORARY);
+ if (!data)
+ return -ENOMEM;
+
+ msg.buf = data;
+
+ memcpy(data, &offset, sizeof(offset));
+ memcpy(data + 1, buffer, size);
+
+ err = i2c_transfer(adapter, &msg, 1);
+
+ kfree(data);
+
+ if (err < 0)
+ return err;
+ if (err != 1)
+ return -EPROTO;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_scdc_write);
new file mode 100644
@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2015 NVIDIA Corporation. All rights reserved.
+ *
+ * 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, sub license,
+ * 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#ifndef DRM_SCDC_HELPER_H
+#define DRM_SCDC_HELPER_H
+
+#include <linux/i2c.h>
+#include <linux/types.h>
+
+#define SCDC_SINK_VERSION 0x01
+
+#define SCDC_SOURCE_VERSION 0x02
+
+#define SCDC_UPDATE_0 0x10
+#define SCDC_READ_REQUEST_TEST (1 << 2)
+#define SCDC_CED_UPDATE (1 << 1)
+#define SCDC_STATUS_UPDATE (1 << 0)
+
+#define SCDC_UPDATE_1 0x11
+
+#define SCDC_TMDS_CONFIG 0x20
+#define SCDC_TMDS_BIT_CLOCK_RATIO_BY_40 (1 << 1)
+#define SCDC_TMDS_BIT_CLOCK_RATIO_BY_10 (0 << 1)
+#define SCDC_SCRAMBLING_ENABLE (1 << 0)
+
+#define SCDC_SCRAMBLER_STATUS 0x21
+#define SCDC_SCRAMBLING_STATUS (1 << 0)
+
+#define SCDC_CONFIG_0 0x30
+#define SCDC_READ_REQUEST_ENABLE (1 << 0)
+
+#define SCDC_STATUS_FLAGS_0 0x40
+#define SCDC_CH2_LOCK (1 < 3)
+#define SCDC_CH1_LOCK (1 < 2)
+#define SCDC_CH0_LOCK (1 < 1)
+#define SCDC_CH_LOCK_MASK (SCDC_CH2_LOCK | SCDC_CH1_LOCK | SCDC_CH0_LOCK)
+#define SCDC_CLOCK_DETECT (1 << 0)
+
+#define SCDC_STATUS_FLAGS_1 0x41
+
+#define SCDC_ERR_DET_0_L 0x50
+#define SCDC_ERR_DET_0_H 0x51
+#define SCDC_ERR_DET_1_L 0x52
+#define SCDC_ERR_DET_1_H 0x53
+#define SCDC_ERR_DET_2_L 0x54
+#define SCDC_ERR_DET_2_H 0x55
+#define SCDC_CHANNEL_VALID (1 << 7)
+
+#define SCDC_ERR_DET_CHECKSUM 0x56
+
+#define SCDC_TEST_CONFIG_0 0xc0
+#define SCDC_TEST_READ_REQUEST (1 << 7)
+#define SCDC_TEST_READ_REQUEST_DELAY(x) ((x) & 0x7f)
+
+#define SCDC_MANUFACTURER_IEEE_OUI 0xd0
+#define SCDC_MANUFACTURER_IEEE_OUI_SIZE 3
+
+#define SCDC_DEVICE_ID 0xd3
+#define SCDC_DEVICE_ID_SIZE 8
+
+#define SCDC_DEVICE_HARDWARE_REVISION 0xdb
+#define SCDC_GET_DEVICE_HARDWARE_REVISION_MAJOR(x) (((x) >> 4) & 0xf)
+#define SCDC_GET_DEVICE_HARDWARE_REVISION_MINOR(x) (((x) >> 0) & 0xf)
+
+#define SCDC_DEVICE_SOFTWARE_MAJOR_REVISION 0xdc
+#define SCDC_DEVICE_SOFTWARE_MINOR_REVISION 0xdd
+
+#define SCDC_MANUFACTURER_SPECIFIC 0xde
+#define SCDC_MANUFACTURER_SPECIFIC_SIZE 34
+
+ssize_t drm_scdc_read(struct i2c_adapter *adapter, u8 offset, void *buffer,
+ size_t size);
+ssize_t drm_scdc_write(struct i2c_adapter *adapter, u8 offset,
+ const void *buffer, size_t size);
+
+/**
+ * drm_scdc_readb - read a single byte from SCDC
+ * @adapter: I2C adapter
+ * @offset: offset of register to read
+ * @value: return location for the register value
+ *
+ * Reads a single byte from SCDC. This is a convenience wrapper around the
+ * drm_scdc_read() function.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+static inline int drm_scdc_readb(struct i2c_adapter *adapter, u8 offset,
+ u8 *value)
+{
+ return drm_scdc_read(adapter, offset, value, sizeof(*value));
+}
+
+/**
+ * drm_scdc_writeb - write a single byte to SCDC
+ * @adapter: I2C adapter
+ * @offset: offset of register to read
+ * @value: return location for the register value
+ *
+ * Writes a single byte to SCDC. This is a convenience wrapper around the
+ * drm_scdc_write() function.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+static inline int drm_scdc_writeb(struct i2c_adapter *adapter, u8 offset,
+ u8 value)
+{
+ return drm_scdc_write(adapter, offset, &value, sizeof(value));
+}
+
+#endif