diff options
| -rw-r--r-- | Documentation/gpu/drm-kms-helpers.rst | 12 | ||||
| -rw-r--r-- | drivers/gpu/drm/Makefile | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_scdc_helper.c | 123 | ||||
| -rw-r--r-- | include/drm/drm_scdc_helper.h | 132 |
4 files changed, 269 insertions, 1 deletions
diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst index ac53c0b893f6..c075aadd7078 100644 --- a/Documentation/gpu/drm-kms-helpers.rst +++ b/Documentation/gpu/drm-kms-helpers.rst @@ -223,6 +223,18 @@ 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 ============================= diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 59aae43005ee..59f0f9b696eb 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -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 diff --git a/drivers/gpu/drm/drm_scdc_helper.c b/drivers/gpu/drm/drm_scdc_helper.c new file mode 100644 index 000000000000..c2dd33f89c17 --- /dev/null +++ b/drivers/gpu/drm/drm_scdc_helper.c @@ -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); diff --git a/include/drm/drm_scdc_helper.h b/include/drm/drm_scdc_helper.h new file mode 100644 index 000000000000..9c52deb13df4 --- /dev/null +++ b/include/drm/drm_scdc_helper.h @@ -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 |