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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/msm/dp/dp_aux.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/msm/dp/dp_aux.c')
-rw-r--r-- | drivers/gpu/drm/msm/dp/dp_aux.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c new file mode 100644 index 000000000..84f9e3e5f --- /dev/null +++ b/drivers/gpu/drm/msm/dp/dp_aux.c @@ -0,0 +1,541 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved. + */ + +#include <linux/delay.h> +#include <drm/drm_print.h> + +#include "dp_reg.h" +#include "dp_aux.h" + +enum msm_dp_aux_err { + DP_AUX_ERR_NONE, + DP_AUX_ERR_ADDR, + DP_AUX_ERR_TOUT, + DP_AUX_ERR_NACK, + DP_AUX_ERR_DEFER, + DP_AUX_ERR_NACK_DEFER, + DP_AUX_ERR_PHY, +}; + +struct dp_aux_private { + struct device *dev; + struct dp_catalog *catalog; + + struct mutex mutex; + struct completion comp; + + enum msm_dp_aux_err aux_error_num; + u32 retry_cnt; + bool cmd_busy; + bool native; + bool read; + bool no_send_addr; + bool no_send_stop; + bool initted; + bool is_edp; + u32 offset; + u32 segment; + + struct drm_dp_aux dp_aux; +}; + +#define MAX_AUX_RETRIES 5 + +static ssize_t dp_aux_write(struct dp_aux_private *aux, + struct drm_dp_aux_msg *msg) +{ + u8 data[4]; + u32 reg; + ssize_t len; + u8 *msgdata = msg->buffer; + int const AUX_CMD_FIFO_LEN = 128; + int i = 0; + + if (aux->read) + len = 0; + else + len = msg->size; + + /* + * cmd fifo only has depth of 144 bytes + * limit buf length to 128 bytes here + */ + if (len > AUX_CMD_FIFO_LEN - 4) { + DRM_ERROR("buf size greater than allowed size of 128 bytes\n"); + return -EINVAL; + } + + /* Pack cmd and write to HW */ + data[0] = (msg->address >> 16) & 0xf; /* addr[19:16] */ + if (aux->read) + data[0] |= BIT(4); /* R/W */ + + data[1] = msg->address >> 8; /* addr[15:8] */ + data[2] = msg->address; /* addr[7:0] */ + data[3] = msg->size - 1; /* len[7:0] */ + + for (i = 0; i < len + 4; i++) { + reg = (i < 4) ? data[i] : msgdata[i - 4]; + reg <<= DP_AUX_DATA_OFFSET; + reg &= DP_AUX_DATA_MASK; + reg |= DP_AUX_DATA_WRITE; + /* index = 0, write */ + if (i == 0) + reg |= DP_AUX_DATA_INDEX_WRITE; + aux->catalog->aux_data = reg; + dp_catalog_aux_write_data(aux->catalog); + } + + dp_catalog_aux_clear_trans(aux->catalog, false); + dp_catalog_aux_clear_hw_interrupts(aux->catalog); + + reg = 0; /* Transaction number == 1 */ + if (!aux->native) { /* i2c */ + reg |= DP_AUX_TRANS_CTRL_I2C; + + if (aux->no_send_addr) + reg |= DP_AUX_TRANS_CTRL_NO_SEND_ADDR; + + if (aux->no_send_stop) + reg |= DP_AUX_TRANS_CTRL_NO_SEND_STOP; + } + + reg |= DP_AUX_TRANS_CTRL_GO; + aux->catalog->aux_data = reg; + dp_catalog_aux_write_trans(aux->catalog); + + return len; +} + +static ssize_t dp_aux_cmd_fifo_tx(struct dp_aux_private *aux, + struct drm_dp_aux_msg *msg) +{ + ssize_t ret; + unsigned long time_left; + + reinit_completion(&aux->comp); + + ret = dp_aux_write(aux, msg); + if (ret < 0) + return ret; + + time_left = wait_for_completion_timeout(&aux->comp, + msecs_to_jiffies(250)); + if (!time_left) + return -ETIMEDOUT; + + return ret; +} + +static ssize_t dp_aux_cmd_fifo_rx(struct dp_aux_private *aux, + struct drm_dp_aux_msg *msg) +{ + u32 data; + u8 *dp; + u32 i, actual_i; + u32 len = msg->size; + + dp_catalog_aux_clear_trans(aux->catalog, true); + + data = DP_AUX_DATA_INDEX_WRITE; /* INDEX_WRITE */ + data |= DP_AUX_DATA_READ; /* read */ + + aux->catalog->aux_data = data; + dp_catalog_aux_write_data(aux->catalog); + + dp = msg->buffer; + + /* discard first byte */ + data = dp_catalog_aux_read_data(aux->catalog); + + for (i = 0; i < len; i++) { + data = dp_catalog_aux_read_data(aux->catalog); + *dp++ = (u8)((data >> DP_AUX_DATA_OFFSET) & 0xff); + + actual_i = (data >> DP_AUX_DATA_INDEX_OFFSET) & 0xFF; + if (i != actual_i) + break; + } + + return i; +} + +static void dp_aux_update_offset_and_segment(struct dp_aux_private *aux, + struct drm_dp_aux_msg *input_msg) +{ + u32 edid_address = 0x50; + u32 segment_address = 0x30; + bool i2c_read = input_msg->request & + (DP_AUX_I2C_READ & DP_AUX_NATIVE_READ); + u8 *data; + + if (aux->native || i2c_read || ((input_msg->address != edid_address) && + (input_msg->address != segment_address))) + return; + + + data = input_msg->buffer; + if (input_msg->address == segment_address) + aux->segment = *data; + else + aux->offset = *data; +} + +/** + * dp_aux_transfer_helper() - helper function for EDID read transactions + * + * @aux: DP AUX private structure + * @input_msg: input message from DRM upstream APIs + * @send_seg: send the segment to sink + * + * return: void + * + * This helper function is used to fix EDID reads for non-compliant + * sinks that do not handle the i2c middle-of-transaction flag correctly. + */ +static void dp_aux_transfer_helper(struct dp_aux_private *aux, + struct drm_dp_aux_msg *input_msg, + bool send_seg) +{ + struct drm_dp_aux_msg helper_msg; + u32 message_size = 0x10; + u32 segment_address = 0x30; + u32 const edid_block_length = 0x80; + bool i2c_mot = input_msg->request & DP_AUX_I2C_MOT; + bool i2c_read = input_msg->request & + (DP_AUX_I2C_READ & DP_AUX_NATIVE_READ); + + if (!i2c_mot || !i2c_read || (input_msg->size == 0)) + return; + + /* + * Sending the segment value and EDID offset will be performed + * from the DRM upstream EDID driver for each block. Avoid + * duplicate AUX transactions related to this while reading the + * first 16 bytes of each block. + */ + if (!(aux->offset % edid_block_length) || !send_seg) + goto end; + + aux->read = false; + aux->cmd_busy = true; + aux->no_send_addr = true; + aux->no_send_stop = true; + + /* + * Send the segment address for every i2c read in which the + * middle-of-tranaction flag is set. This is required to support EDID + * reads of more than 2 blocks as the segment address is reset to 0 + * since we are overriding the middle-of-transaction flag for read + * transactions. + */ + + if (aux->segment) { + memset(&helper_msg, 0, sizeof(helper_msg)); + helper_msg.address = segment_address; + helper_msg.buffer = &aux->segment; + helper_msg.size = 1; + dp_aux_cmd_fifo_tx(aux, &helper_msg); + } + + /* + * Send the offset address for every i2c read in which the + * middle-of-transaction flag is set. This will ensure that the sink + * will update its read pointer and return the correct portion of the + * EDID buffer in the subsequent i2c read trasntion triggered in the + * native AUX transfer function. + */ + memset(&helper_msg, 0, sizeof(helper_msg)); + helper_msg.address = input_msg->address; + helper_msg.buffer = &aux->offset; + helper_msg.size = 1; + dp_aux_cmd_fifo_tx(aux, &helper_msg); + +end: + aux->offset += message_size; + if (aux->offset == 0x80 || aux->offset == 0x100) + aux->segment = 0x0; /* reset segment at end of block */ +} + +/* + * This function does the real job to process an AUX transaction. + * It will call aux_reset() function to reset the AUX channel, + * if the waiting is timeout. + */ +static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux, + struct drm_dp_aux_msg *msg) +{ + ssize_t ret; + int const aux_cmd_native_max = 16; + int const aux_cmd_i2c_max = 128; + struct dp_aux_private *aux; + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + aux->native = msg->request & (DP_AUX_NATIVE_WRITE & DP_AUX_NATIVE_READ); + + /* Ignore address only message */ + if (msg->size == 0 || !msg->buffer) { + msg->reply = aux->native ? + DP_AUX_NATIVE_REPLY_ACK : DP_AUX_I2C_REPLY_ACK; + return msg->size; + } + + /* msg sanity check */ + if ((aux->native && msg->size > aux_cmd_native_max) || + msg->size > aux_cmd_i2c_max) { + DRM_ERROR("%s: invalid msg: size(%zu), request(%x)\n", + __func__, msg->size, msg->request); + return -EINVAL; + } + + mutex_lock(&aux->mutex); + if (!aux->initted) { + ret = -EIO; + goto exit; + } + + /* + * For eDP it's important to give a reasonably long wait here for HPD + * to be asserted. This is because the panel driver may have _just_ + * turned on the panel and then tried to do an AUX transfer. The panel + * driver has no way of knowing when the panel is ready, so it's up + * to us to wait. For DP we never get into this situation so let's + * avoid ever doing the extra long wait for DP. + */ + if (aux->is_edp) { + ret = dp_catalog_aux_wait_for_hpd_connect_state(aux->catalog); + if (ret) { + DRM_DEBUG_DP("Panel not ready for aux transactions\n"); + goto exit; + } + } + + dp_aux_update_offset_and_segment(aux, msg); + dp_aux_transfer_helper(aux, msg, true); + + aux->read = msg->request & (DP_AUX_I2C_READ & DP_AUX_NATIVE_READ); + aux->cmd_busy = true; + + if (aux->read) { + aux->no_send_addr = true; + aux->no_send_stop = false; + } else { + aux->no_send_addr = true; + aux->no_send_stop = true; + } + + ret = dp_aux_cmd_fifo_tx(aux, msg); + if (ret < 0) { + if (aux->native) { + aux->retry_cnt++; + if (!(aux->retry_cnt % MAX_AUX_RETRIES)) + dp_catalog_aux_update_cfg(aux->catalog); + } + /* reset aux if link is in connected state */ + if (dp_catalog_link_is_connected(aux->catalog)) + dp_catalog_aux_reset(aux->catalog); + } else { + aux->retry_cnt = 0; + switch (aux->aux_error_num) { + case DP_AUX_ERR_NONE: + if (aux->read) + ret = dp_aux_cmd_fifo_rx(aux, msg); + msg->reply = aux->native ? DP_AUX_NATIVE_REPLY_ACK : DP_AUX_I2C_REPLY_ACK; + break; + case DP_AUX_ERR_DEFER: + msg->reply = aux->native ? DP_AUX_NATIVE_REPLY_DEFER : DP_AUX_I2C_REPLY_DEFER; + break; + case DP_AUX_ERR_PHY: + case DP_AUX_ERR_ADDR: + case DP_AUX_ERR_NACK: + case DP_AUX_ERR_NACK_DEFER: + msg->reply = aux->native ? DP_AUX_NATIVE_REPLY_NACK : DP_AUX_I2C_REPLY_NACK; + break; + case DP_AUX_ERR_TOUT: + ret = -ETIMEDOUT; + break; + } + } + + aux->cmd_busy = false; + +exit: + mutex_unlock(&aux->mutex); + + return ret; +} + +void dp_aux_isr(struct drm_dp_aux *dp_aux) +{ + u32 isr; + struct dp_aux_private *aux; + + if (!dp_aux) { + DRM_ERROR("invalid input\n"); + return; + } + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + isr = dp_catalog_aux_get_irq(aux->catalog); + + /* no interrupts pending, return immediately */ + if (!isr) + return; + + if (!aux->cmd_busy) { + DRM_ERROR("Unexpected DP AUX IRQ %#010x when not busy\n", isr); + return; + } + + /* + * The logic below assumes only one error bit is set (other than "done" + * which can apparently be set at the same time as some of the other + * bits). Warn if more than one get set so we know we need to improve + * the logic. + */ + if (hweight32(isr & ~DP_INTR_AUX_XFER_DONE) > 1) + DRM_WARN("Some DP AUX interrupts unhandled: %#010x\n", isr); + + if (isr & DP_INTR_AUX_ERROR) { + aux->aux_error_num = DP_AUX_ERR_PHY; + dp_catalog_aux_clear_hw_interrupts(aux->catalog); + } else if (isr & DP_INTR_NACK_DEFER) { + aux->aux_error_num = DP_AUX_ERR_NACK_DEFER; + } else if (isr & DP_INTR_WRONG_ADDR) { + aux->aux_error_num = DP_AUX_ERR_ADDR; + } else if (isr & DP_INTR_TIMEOUT) { + aux->aux_error_num = DP_AUX_ERR_TOUT; + } else if (!aux->native && (isr & DP_INTR_I2C_NACK)) { + aux->aux_error_num = DP_AUX_ERR_NACK; + } else if (!aux->native && (isr & DP_INTR_I2C_DEFER)) { + if (isr & DP_INTR_AUX_XFER_DONE) + aux->aux_error_num = DP_AUX_ERR_NACK; + else + aux->aux_error_num = DP_AUX_ERR_DEFER; + } else if (isr & DP_INTR_AUX_XFER_DONE) { + aux->aux_error_num = DP_AUX_ERR_NONE; + } else { + DRM_WARN("Unexpected interrupt: %#010x\n", isr); + return; + } + + complete(&aux->comp); +} + +void dp_aux_reconfig(struct drm_dp_aux *dp_aux) +{ + struct dp_aux_private *aux; + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + dp_catalog_aux_update_cfg(aux->catalog); + dp_catalog_aux_reset(aux->catalog); +} + +void dp_aux_init(struct drm_dp_aux *dp_aux) +{ + struct dp_aux_private *aux; + + if (!dp_aux) { + DRM_ERROR("invalid input\n"); + return; + } + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + mutex_lock(&aux->mutex); + + dp_catalog_aux_enable(aux->catalog, true); + aux->retry_cnt = 0; + aux->initted = true; + + mutex_unlock(&aux->mutex); +} + +void dp_aux_deinit(struct drm_dp_aux *dp_aux) +{ + struct dp_aux_private *aux; + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + mutex_lock(&aux->mutex); + + aux->initted = false; + dp_catalog_aux_enable(aux->catalog, false); + + mutex_unlock(&aux->mutex); +} + +int dp_aux_register(struct drm_dp_aux *dp_aux) +{ + struct dp_aux_private *aux; + int ret; + + if (!dp_aux) { + DRM_ERROR("invalid input\n"); + return -EINVAL; + } + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + aux->dp_aux.name = "dpu_dp_aux"; + aux->dp_aux.dev = aux->dev; + aux->dp_aux.transfer = dp_aux_transfer; + ret = drm_dp_aux_register(&aux->dp_aux); + if (ret) { + DRM_ERROR("%s: failed to register drm aux: %d\n", __func__, + ret); + return ret; + } + + return 0; +} + +void dp_aux_unregister(struct drm_dp_aux *dp_aux) +{ + drm_dp_aux_unregister(dp_aux); +} + +struct drm_dp_aux *dp_aux_get(struct device *dev, struct dp_catalog *catalog, + bool is_edp) +{ + struct dp_aux_private *aux; + + if (!catalog) { + DRM_ERROR("invalid input\n"); + return ERR_PTR(-ENODEV); + } + + aux = devm_kzalloc(dev, sizeof(*aux), GFP_KERNEL); + if (!aux) + return ERR_PTR(-ENOMEM); + + init_completion(&aux->comp); + aux->cmd_busy = false; + aux->is_edp = is_edp; + mutex_init(&aux->mutex); + + aux->dev = dev; + aux->catalog = catalog; + aux->retry_cnt = 0; + + return &aux->dp_aux; +} + +void dp_aux_put(struct drm_dp_aux *dp_aux) +{ + struct dp_aux_private *aux; + + if (!dp_aux) + return; + + aux = container_of(dp_aux, struct dp_aux_private, dp_aux); + + mutex_destroy(&aux->mutex); + + devm_kfree(aux->dev, aux); +} |