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Diffstat (limited to 'sound/soc/sdca/sdca_ump.c')
| -rw-r--r-- | sound/soc/sdca/sdca_ump.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/sound/soc/sdca/sdca_ump.c b/sound/soc/sdca/sdca_ump.c new file mode 100644 index 000000000000..8aba3ff16872 --- /dev/null +++ b/sound/soc/sdca/sdca_ump.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2025 Cirrus Logic, Inc. and +// Cirrus Logic International Semiconductor Ltd. + +/* + * The MIPI SDCA specification is available for public downloads at + * https://www.mipi.org/mipi-sdca-v1-0-download + */ + +#include <linux/dev_printk.h> +#include <linux/device.h> +#include <linux/regmap.h> +#include <sound/sdca.h> +#include <sound/sdca_function.h> +#include <sound/sdca_ump.h> +#include <sound/soc-component.h> +#include <linux/soundwire/sdw_registers.h> + +/** + * sdca_ump_get_owner_host - check a UMP buffer is owned by the host + * @dev: Pointer to the struct device used for error messages. + * @function_regmap: Pointer to the regmap for the SDCA Function. + * @function: Pointer to the Function information. + * @entity: Pointer to the SDCA Entity. + * @control: Pointer to the SDCA Control for the UMP Owner. + * + * Return: Returns zero on success, and a negative error code on failure. + */ +int sdca_ump_get_owner_host(struct device *dev, + struct regmap *function_regmap, + struct sdca_function_data *function, + struct sdca_entity *entity, + struct sdca_control *control) +{ + unsigned int reg, owner; + int ret; + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, control->sel, 0); + ret = regmap_read(function_regmap, reg, &owner); + if (ret < 0) { + dev_err(dev, "%s: failed to read UMP owner: %d\n", + entity->label, ret); + return ret; + } + + if (owner != SDCA_UMP_OWNER_HOST) { + dev_err(dev, "%s: host is not the UMP owner\n", entity->label); + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_get_owner_host, "SND_SOC_SDCA"); + +/** + * sdca_ump_set_owner_device - set a UMP buffer's ownership back to the device + * @dev: Pointer to the struct device used for error messages. + * @function_regmap: Pointer to the regmap for the SDCA Function. + * @function: Pointer to the Function information. + * @entity: Pointer to the SDCA Entity. + * @control: Pointer to the SDCA Control for the UMP Owner. + * + * Return: Returns zero on success, and a negative error code on failure. + */ +int sdca_ump_set_owner_device(struct device *dev, + struct regmap *function_regmap, + struct sdca_function_data *function, + struct sdca_entity *entity, + struct sdca_control *control) +{ + unsigned int reg; + int ret; + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, control->sel, 0); + ret = regmap_write(function_regmap, reg, SDCA_UMP_OWNER_DEVICE); + if (ret < 0) + dev_err(dev, "%s: failed to write UMP owner: %d\n", + entity->label, ret); + + return ret; +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_set_owner_device, "SND_SOC_SDCA"); + +/** + * sdca_ump_read_message - read a UMP message from the device + * @dev: Pointer to the struct device used for error messages. + * @device_regmap: Pointer to the Device register map. + * @function_regmap: Pointer to the regmap for the SDCA Function. + * @function: Pointer to the Function information. + * @entity: Pointer to the SDCA Entity. + * @offset_sel: Control Selector for the UMP Offset Control. + * @length_sel: Control Selector for the UMP Length Control. + * @msg: Pointer that will be populated with an dynamically buffer + * containing the UMP message. Note this needs to be freed by the + * caller. + * + * The caller should first call sdca_ump_get_owner_host() to ensure the host + * currently owns the UMP buffer, and then this function can be used to + * retrieve a message. It is the callers responsibility to free the + * message once it is finished with it. Finally sdca_ump_set_owner_device() + * should be called to return the buffer to the device. + * + * Return: Returns the message length on success, and a negative error + * code on failure. + */ +int sdca_ump_read_message(struct device *dev, + struct regmap *device_regmap, + struct regmap *function_regmap, + struct sdca_function_data *function, + struct sdca_entity *entity, + unsigned int offset_sel, unsigned int length_sel, + void **msg) +{ + struct sdca_control_range *range; + unsigned int msg_offset, msg_len; + unsigned int buf_addr, buf_len; + unsigned int reg; + int ret; + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, offset_sel, 0); + ret = regmap_read(function_regmap, reg, &msg_offset); + if (ret < 0) { + dev_err(dev, "%s: failed to read UMP offset: %d\n", + entity->label, ret); + return ret; + } + + range = sdca_selector_find_range(dev, entity, offset_sel, + SDCA_MESSAGEOFFSET_NCOLS, 1); + if (!range) + return -ENOENT; + + buf_addr = sdca_range(range, SDCA_MESSAGEOFFSET_BUFFER_START_ADDRESS, 0); + buf_len = sdca_range(range, SDCA_MESSAGEOFFSET_BUFFER_LENGTH, 0); + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, length_sel, 0); + ret = regmap_read(function_regmap, reg, &msg_len); + if (ret < 0) { + dev_err(dev, "%s: failed to read UMP length: %d\n", + entity->label, ret); + return ret; + } + + if (msg_len > buf_len - msg_offset) { + dev_err(dev, "%s: message too big for UMP buffer: %d\n", + entity->label, msg_len); + return -EINVAL; + } + + *msg = kmalloc(msg_len, GFP_KERNEL); + if (!*msg) + return -ENOMEM; + + ret = regmap_raw_read(device_regmap, buf_addr + msg_offset, *msg, msg_len); + if (ret < 0) { + dev_err(dev, "%s: failed to read UMP message: %d\n", + entity->label, ret); + return ret; + } + + return msg_len; +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_read_message, "SND_SOC_SDCA"); + +/** + * sdca_ump_write_message - write a UMP message to the device + * @dev: Pointer to the struct device used for error messages. + * @device_regmap: Pointer to the Device register map. + * @function_regmap: Pointer to the regmap for the SDCA Function. + * @function: Pointer to the Function information. + * @entity: Pointer to the SDCA Entity. + * @offset_sel: Control Selector for the UMP Offset Control. + * @msg_offset: Offset within the UMP buffer at which the message should + * be written. + * @length_sel: Control Selector for the UMP Length Control. + * @msg: Pointer to the data that should be written to the UMP buffer. + * @msg_len: Length of the message data in bytes. + * + * The caller should first call sdca_ump_get_owner_host() to ensure the host + * currently owns the UMP buffer, and then this function can be used to + * write a message. Finally sdca_ump_set_owner_device() should be called to + * return the buffer to the device, allowing the device to access the + * message. + * + * Return: Returns zero on success, and a negative error code on failure. + */ +int sdca_ump_write_message(struct device *dev, + struct regmap *device_regmap, + struct regmap *function_regmap, + struct sdca_function_data *function, + struct sdca_entity *entity, + unsigned int offset_sel, unsigned int msg_offset, + unsigned int length_sel, + void *msg, int msg_len) +{ + struct sdca_control_range *range; + unsigned int buf_addr, buf_len, ump_mode; + unsigned int reg; + int ret; + + range = sdca_selector_find_range(dev, entity, offset_sel, + SDCA_MESSAGEOFFSET_NCOLS, 1); + if (!range) + return -ENOENT; + + buf_addr = sdca_range(range, SDCA_MESSAGEOFFSET_BUFFER_START_ADDRESS, 0); + buf_len = sdca_range(range, SDCA_MESSAGEOFFSET_BUFFER_LENGTH, 0); + ump_mode = sdca_range(range, SDCA_MESSAGEOFFSET_UMP_MODE, 0); + + if (msg_len > buf_len - msg_offset) { + dev_err(dev, "%s: message too big for UMP buffer: %d\n", + entity->label, msg_len); + return -EINVAL; + } + + if (ump_mode != SDCA_UMP_MODE_DIRECT) { + dev_err(dev, "%s: only direct mode currently supported\n", + entity->label); + return -EINVAL; + } + + ret = regmap_raw_write(device_regmap, buf_addr + msg_offset, msg, msg_len); + if (ret) { + dev_err(dev, "%s: failed to write UMP message: %d\n", + entity->label, ret); + return ret; + } + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, offset_sel, 0); + ret = regmap_write(function_regmap, reg, msg_offset); + if (ret < 0) { + dev_err(dev, "%s: failed to write UMP offset: %d\n", + entity->label, ret); + return ret; + } + + reg = SDW_SDCA_CTL(function->desc->adr, entity->id, length_sel, 0); + ret = regmap_write(function_regmap, reg, msg_len); + if (ret < 0) { + dev_err(dev, "%s: failed to write UMP length: %d\n", + entity->label, ret); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_write_message, "SND_SOC_SDCA"); + +void sdca_ump_cancel_timeout(struct delayed_work *work) +{ + cancel_delayed_work_sync(work); +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_cancel_timeout, "SND_SOC_SDCA"); + +void sdca_ump_schedule_timeout(struct delayed_work *work, unsigned int timeout_us) +{ + if (!timeout_us) + return; + + queue_delayed_work(system_wq, work, usecs_to_jiffies(timeout_us)); +} +EXPORT_SYMBOL_NS_GPL(sdca_ump_schedule_timeout, "SND_SOC_SDCA"); |