diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dp_dual_mode_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_dual_mode_helper.c | 489 |
1 files changed, 0 insertions, 489 deletions
diff --git a/drivers/gpu/drm/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/drm_dp_dual_mode_helper.c deleted file mode 100644 index 80e62f669321..000000000000 --- a/drivers/gpu/drm/drm_dp_dual_mode_helper.c +++ /dev/null @@ -1,489 +0,0 @@ -/* - * Copyright © 2016 Intel Corporation - * - * 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. - */ - -#include <linux/errno.h> -#include <linux/export.h> -#include <linux/i2c.h> -#include <linux/slab.h> -#include <linux/string.h> -#include <drm/drm_dp_dual_mode_helper.h> -#include <drm/drmP.h> - -/** - * DOC: dp dual mode helpers - * - * Helper functions to deal with DP dual mode (aka. DP++) adaptors. - * - * Type 1: - * Adaptor registers (if any) and the sink DDC bus may be accessed via I2C. - * - * Type 2: - * Adaptor registers and sink DDC bus can be accessed either via I2C or - * I2C-over-AUX. Source devices may choose to implement either of these - * access methods. - */ - -#define DP_DUAL_MODE_SLAVE_ADDRESS 0x40 - -/** - * drm_dp_dual_mode_read - Read from the DP dual mode adaptor register(s) - * @adapter: I2C adapter for the DDC bus - * @offset: register offset - * @buffer: buffer for return data - * @size: sizo of the buffer - * - * Reads @size bytes from the DP dual mode adaptor registers - * starting at @offset. - * - * Returns: - * 0 on success, negative error code on failure - */ -ssize_t drm_dp_dual_mode_read(struct i2c_adapter *adapter, - u8 offset, void *buffer, size_t size) -{ - struct i2c_msg msgs[] = { - { - .addr = DP_DUAL_MODE_SLAVE_ADDRESS, - .flags = 0, - .len = 1, - .buf = &offset, - }, - { - .addr = DP_DUAL_MODE_SLAVE_ADDRESS, - .flags = I2C_M_RD, - .len = size, - .buf = buffer, - }, - }; - int ret; - - 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_dp_dual_mode_read); - -/** - * drm_dp_dual_mode_write - Write to the DP dual mode adaptor register(s) - * @adapter: I2C adapter for the DDC bus - * @offset: register offset - * @buffer: buffer for write data - * @size: sizo of the buffer - * - * Writes @size bytes to the DP dual mode adaptor registers - * starting at @offset. - * - * Returns: - * 0 on success, negative error code on failure - */ -ssize_t drm_dp_dual_mode_write(struct i2c_adapter *adapter, - u8 offset, const void *buffer, size_t size) -{ - struct i2c_msg msg = { - .addr = DP_DUAL_MODE_SLAVE_ADDRESS, - .flags = 0, - .len = 1 + size, - .buf = NULL, - }; - void *data; - int ret; - - data = kmalloc(msg.len, GFP_TEMPORARY); - if (!data) - return -ENOMEM; - - msg.buf = data; - - memcpy(data, &offset, 1); - memcpy(data + 1, buffer, size); - - ret = i2c_transfer(adapter, &msg, 1); - - kfree(data); - - if (ret < 0) - return ret; - if (ret != 1) - return -EPROTO; - - return 0; -} -EXPORT_SYMBOL(drm_dp_dual_mode_write); - -static bool is_hdmi_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN]) -{ - static const char dp_dual_mode_hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN] = - "DP-HDMI ADAPTOR\x04"; - - return memcmp(hdmi_id, dp_dual_mode_hdmi_id, - sizeof(dp_dual_mode_hdmi_id)) == 0; -} - -static bool is_type1_adaptor(uint8_t adaptor_id) -{ - return adaptor_id == 0 || adaptor_id == 0xff; -} - -static bool is_type2_adaptor(uint8_t adaptor_id) -{ - return adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 | - DP_DUAL_MODE_REV_TYPE2); -} - -static bool is_lspcon_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN], - const uint8_t adaptor_id) -{ - return is_hdmi_adaptor(hdmi_id) && - (adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 | - DP_DUAL_MODE_TYPE_HAS_DPCD)); -} - -/** - * drm_dp_dual_mode_detect - Identify the DP dual mode adaptor - * @adapter: I2C adapter for the DDC bus - * - * Attempt to identify the type of the DP dual mode adaptor used. - * - * Note that when the answer is @DRM_DP_DUAL_MODE_UNKNOWN it's not - * certain whether we're dealing with a native HDMI port or - * a type 1 DVI dual mode adaptor. The driver will have to use - * some other hardware/driver specific mechanism to make that - * distinction. - * - * Returns: - * The type of the DP dual mode adaptor used - */ -enum drm_dp_dual_mode_type drm_dp_dual_mode_detect(struct i2c_adapter *adapter) -{ - char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN] = {}; - uint8_t adaptor_id = 0x00; - ssize_t ret; - - /* - * Let's see if the adaptor is there the by reading the - * HDMI ID registers. - * - * Note that type 1 DVI adaptors are not required to implemnt - * any registers, and that presents a problem for detection. - * If the i2c transfer is nacked, we may or may not be dealing - * with a type 1 DVI adaptor. Some other mechanism of detecting - * the presence of the adaptor is required. One way would be - * to check the state of the CONFIG1 pin, Another method would - * simply require the driver to know whether the port is a DP++ - * port or a native HDMI port. Both of these methods are entirely - * hardware/driver specific so we can't deal with them here. - */ - ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_HDMI_ID, - hdmi_id, sizeof(hdmi_id)); - DRM_DEBUG_KMS("DP dual mode HDMI ID: %*pE (err %zd)\n", - ret ? 0 : (int)sizeof(hdmi_id), hdmi_id, ret); - if (ret) - return DRM_DP_DUAL_MODE_UNKNOWN; - - /* - * Sigh. Some (maybe all?) type 1 adaptors are broken and ack - * the offset but ignore it, and instead they just always return - * data from the start of the HDMI ID buffer. So for a broken - * type 1 HDMI adaptor a single byte read will always give us - * 0x44, and for a type 1 DVI adaptor it should give 0x00 - * (assuming it implements any registers). Fortunately neither - * of those values will match the type 2 signature of the - * DP_DUAL_MODE_ADAPTOR_ID register so we can proceed with - * the type 2 adaptor detection safely even in the presence - * of broken type 1 adaptors. - */ - ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_ADAPTOR_ID, - &adaptor_id, sizeof(adaptor_id)); - DRM_DEBUG_KMS("DP dual mode adaptor ID: %02x (err %zd)\n", - adaptor_id, ret); - if (ret == 0) { - if (is_lspcon_adaptor(hdmi_id, adaptor_id)) - return DRM_DP_DUAL_MODE_LSPCON; - if (is_type2_adaptor(adaptor_id)) { - if (is_hdmi_adaptor(hdmi_id)) - return DRM_DP_DUAL_MODE_TYPE2_HDMI; - else - return DRM_DP_DUAL_MODE_TYPE2_DVI; - } - /* - * If neither a proper type 1 ID nor a broken type 1 adaptor - * as described above, assume type 1, but let the user know - * that we may have misdetected the type. - */ - if (!is_type1_adaptor(adaptor_id) && adaptor_id != hdmi_id[0]) - DRM_ERROR("Unexpected DP dual mode adaptor ID %02x\n", - adaptor_id); - - } - - if (is_hdmi_adaptor(hdmi_id)) - return DRM_DP_DUAL_MODE_TYPE1_HDMI; - else - return DRM_DP_DUAL_MODE_TYPE1_DVI; -} -EXPORT_SYMBOL(drm_dp_dual_mode_detect); - -/** - * drm_dp_dual_mode_max_tmds_clock - Max TMDS clock for DP dual mode adaptor - * @type: DP dual mode adaptor type - * @adapter: I2C adapter for the DDC bus - * - * Determine the max TMDS clock the adaptor supports based on the - * type of the dual mode adaptor and the DP_DUAL_MODE_MAX_TMDS_CLOCK - * register (on type2 adaptors). As some type 1 adaptors have - * problems with registers (see comments in drm_dp_dual_mode_detect()) - * we don't read the register on those, instead we simply assume - * a 165 MHz limit based on the specification. - * - * Returns: - * Maximum supported TMDS clock rate for the DP dual mode adaptor in kHz. - */ -int drm_dp_dual_mode_max_tmds_clock(enum drm_dp_dual_mode_type type, - struct i2c_adapter *adapter) -{ - uint8_t max_tmds_clock; - ssize_t ret; - - /* native HDMI so no limit */ - if (type == DRM_DP_DUAL_MODE_NONE) - return 0; - - /* - * Type 1 adaptors are limited to 165MHz - * Type 2 adaptors can tells us their limit - */ - if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) - return 165000; - - ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_MAX_TMDS_CLOCK, - &max_tmds_clock, sizeof(max_tmds_clock)); - if (ret || max_tmds_clock == 0x00 || max_tmds_clock == 0xff) { - DRM_DEBUG_KMS("Failed to query max TMDS clock\n"); - return 165000; - } - - return max_tmds_clock * 5000 / 2; -} -EXPORT_SYMBOL(drm_dp_dual_mode_max_tmds_clock); - -/** - * drm_dp_dual_mode_get_tmds_output - Get the state of the TMDS output buffers in the DP dual mode adaptor - * @type: DP dual mode adaptor type - * @adapter: I2C adapter for the DDC bus - * @enabled: current state of the TMDS output buffers - * - * Get the state of the TMDS output buffers in the adaptor. For - * type2 adaptors this is queried from the DP_DUAL_MODE_TMDS_OEN - * register. As some type 1 adaptors have problems with registers - * (see comments in drm_dp_dual_mode_detect()) we don't read the - * register on those, instead we simply assume that the buffers - * are always enabled. - * - * Returns: - * 0 on success, negative error code on failure - */ -int drm_dp_dual_mode_get_tmds_output(enum drm_dp_dual_mode_type type, - struct i2c_adapter *adapter, - bool *enabled) -{ - uint8_t tmds_oen; - ssize_t ret; - - if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) { - *enabled = true; - return 0; - } - - ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_TMDS_OEN, - &tmds_oen, sizeof(tmds_oen)); - if (ret) { - DRM_DEBUG_KMS("Failed to query state of TMDS output buffers\n"); - return ret; - } - - *enabled = !(tmds_oen & DP_DUAL_MODE_TMDS_DISABLE); - - return 0; -} -EXPORT_SYMBOL(drm_dp_dual_mode_get_tmds_output); - -/** - * drm_dp_dual_mode_set_tmds_output - Enable/disable TMDS output buffers in the DP dual mode adaptor - * @type: DP dual mode adaptor type - * @adapter: I2C adapter for the DDC bus - * @enable: enable (as opposed to disable) the TMDS output buffers - * - * Set the state of the TMDS output buffers in the adaptor. For - * type2 this is set via the DP_DUAL_MODE_TMDS_OEN register. As - * some type 1 adaptors have problems with registers (see comments - * in drm_dp_dual_mode_detect()) we avoid touching the register, - * making this function a no-op on type 1 adaptors. - * - * Returns: - * 0 on success, negative error code on failure - */ -int drm_dp_dual_mode_set_tmds_output(enum drm_dp_dual_mode_type type, - struct i2c_adapter *adapter, bool enable) -{ - uint8_t tmds_oen = enable ? 0 : DP_DUAL_MODE_TMDS_DISABLE; - ssize_t ret; - - if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) - return 0; - - ret = drm_dp_dual_mode_write(adapter, DP_DUAL_MODE_TMDS_OEN, - &tmds_oen, sizeof(tmds_oen)); - if (ret) { - DRM_DEBUG_KMS("Failed to %s TMDS output buffers\n", - enable ? "enable" : "disable"); - return ret; - } - - return 0; -} -EXPORT_SYMBOL(drm_dp_dual_mode_set_tmds_output); - -/** - * drm_dp_get_dual_mode_type_name - Get the name of the DP dual mode adaptor type as a string - * @type: DP dual mode adaptor type - * - * Returns: - * String representation of the DP dual mode adaptor type - */ -const char *drm_dp_get_dual_mode_type_name(enum drm_dp_dual_mode_type type) -{ - switch (type) { - case DRM_DP_DUAL_MODE_NONE: - return "none"; - case DRM_DP_DUAL_MODE_TYPE1_DVI: - return "type 1 DVI"; - case DRM_DP_DUAL_MODE_TYPE1_HDMI: - return "type 1 HDMI"; - case DRM_DP_DUAL_MODE_TYPE2_DVI: - return "type 2 DVI"; - case DRM_DP_DUAL_MODE_TYPE2_HDMI: - return "type 2 HDMI"; - case DRM_DP_DUAL_MODE_LSPCON: - return "lspcon"; - default: - WARN_ON(type != DRM_DP_DUAL_MODE_UNKNOWN); - return "unknown"; - } -} -EXPORT_SYMBOL(drm_dp_get_dual_mode_type_name); - -/** - * drm_lspcon_get_mode: Get LSPCON's current mode of operation by - * reading offset (0x80, 0x41) - * @adapter: I2C-over-aux adapter - * @mode: current lspcon mode of operation output variable - * - * Returns: - * 0 on success, sets the current_mode value to appropriate mode - * -error on failure - */ -int drm_lspcon_get_mode(struct i2c_adapter *adapter, - enum drm_lspcon_mode *mode) -{ - u8 data; - int ret = 0; - - if (!mode) { - DRM_ERROR("NULL input\n"); - return -EINVAL; - } - - /* Read Status: i2c over aux */ - ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_LSPCON_CURRENT_MODE, - &data, sizeof(data)); - if (ret < 0) { - DRM_ERROR("LSPCON read(0x80, 0x41) failed\n"); - return -EFAULT; - } - - if (data & DP_DUAL_MODE_LSPCON_MODE_PCON) - *mode = DRM_LSPCON_MODE_PCON; - else - *mode = DRM_LSPCON_MODE_LS; - return 0; -} -EXPORT_SYMBOL(drm_lspcon_get_mode); - -/** - * drm_lspcon_set_mode: Change LSPCON's mode of operation by - * writing offset (0x80, 0x40) - * @adapter: I2C-over-aux adapter - * @mode: required mode of operation - * - * Returns: - * 0 on success, -error on failure/timeout - */ -int drm_lspcon_set_mode(struct i2c_adapter *adapter, - enum drm_lspcon_mode mode) -{ - u8 data = 0; - int ret; - int time_out = 200; - enum drm_lspcon_mode current_mode; - - if (mode == DRM_LSPCON_MODE_PCON) - data = DP_DUAL_MODE_LSPCON_MODE_PCON; - - /* Change mode */ - ret = drm_dp_dual_mode_write(adapter, DP_DUAL_MODE_LSPCON_MODE_CHANGE, - &data, sizeof(data)); - if (ret < 0) { - DRM_ERROR("LSPCON mode change failed\n"); - return ret; - } - - /* - * Confirm mode change by reading the status bit. - * Sometimes, it takes a while to change the mode, - * so wait and retry until time out or done. - */ - do { - ret = drm_lspcon_get_mode(adapter, ¤t_mode); - if (ret) { - DRM_ERROR("can't confirm LSPCON mode change\n"); - return ret; - } else { - if (current_mode != mode) { - msleep(10); - time_out -= 10; - } else { - DRM_DEBUG_KMS("LSPCON mode changed to %s\n", - mode == DRM_LSPCON_MODE_LS ? - "LS" : "PCON"); - return 0; - } - } - } while (time_out); - - DRM_ERROR("LSPCON mode change timed out\n"); - return -ETIMEDOUT; -} -EXPORT_SYMBOL(drm_lspcon_set_mode); |