From 87800c4342a29d4e1c378ce72d27e3976d094ffa Mon Sep 17 00:00:00 2001 From: Nuno Sa Date: Fri, 19 Apr 2024 10:25:41 +0200 Subject: iio: backend: add new functionality This adds the needed backend ops for supporting a backend inerfacing with an high speed dac. The new ops are: * data_source_set(); * set_sampling_freq(); * extend_chan_spec(); * ext_info_set(); * ext_info_get(). Also to note the new helpers that are meant to be used by the backends when extending an IIO channel (adding extended info): * iio_backend_ext_info_set(); * iio_backend_ext_info_get(). Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240419-iio-backend-axi-dac-v4-8-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron --- include/linux/iio/backend.h | 49 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) (limited to 'include/linux/iio/backend.h') diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h index a6d79381866e..9d144631134d 100644 --- a/include/linux/iio/backend.h +++ b/include/linux/iio/backend.h @@ -4,6 +4,7 @@ #include +struct iio_chan_spec; struct fwnode_handle; struct iio_backend; struct device; @@ -15,6 +16,26 @@ enum iio_backend_data_type { IIO_BACKEND_DATA_TYPE_MAX }; +enum iio_backend_data_source { + IIO_BACKEND_INTERNAL_CONTINUOS_WAVE, + IIO_BACKEND_EXTERNAL, + IIO_BACKEND_DATA_SOURCE_MAX +}; + +/** + * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute + * @_name: Attribute name + * @_shared: Whether the attribute is shared between all channels + * @_what: Data private to the driver + */ +#define IIO_BACKEND_EX_INFO(_name, _shared, _what) { \ + .name = (_name), \ + .shared = (_shared), \ + .read = iio_backend_ext_info_get, \ + .write = iio_backend_ext_info_set, \ + .private = (_what), \ +} + /** * struct iio_backend_data_fmt - Backend data format * @type: Data type. @@ -35,8 +56,13 @@ struct iio_backend_data_fmt { * @chan_enable: Enable one channel. * @chan_disable: Disable one channel. * @data_format_set: Configure the data format for a specific channel. + * @data_source_set: Configure the data source for a specific channel. + * @set_sample_rate: Configure the sampling rate for a specific channel. * @request_buffer: Request an IIO buffer. * @free_buffer: Free an IIO buffer. + * @extend_chan_spec: Extend an IIO channel. + * @ext_info_set: Extended info setter. + * @ext_info_get: Extended info getter. **/ struct iio_backend_ops { int (*enable)(struct iio_backend *back); @@ -45,10 +71,21 @@ struct iio_backend_ops { int (*chan_disable)(struct iio_backend *back, unsigned int chan); int (*data_format_set)(struct iio_backend *back, unsigned int chan, const struct iio_backend_data_fmt *data); + int (*data_source_set)(struct iio_backend *back, unsigned int chan, + enum iio_backend_data_source data); + int (*set_sample_rate)(struct iio_backend *back, unsigned int chan, + u64 sample_rate_hz); struct iio_buffer *(*request_buffer)(struct iio_backend *back, struct iio_dev *indio_dev); void (*free_buffer)(struct iio_backend *back, struct iio_buffer *buffer); + int (*extend_chan_spec)(struct iio_backend *back, + struct iio_chan_spec *chan); + int (*ext_info_set)(struct iio_backend *back, uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len); + int (*ext_info_get)(struct iio_backend *back, uintptr_t private, + const struct iio_chan_spec *chan, char *buf); }; int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan); @@ -56,10 +93,22 @@ int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan); int devm_iio_backend_enable(struct device *dev, struct iio_backend *back); int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan, const struct iio_backend_data_fmt *data); +int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan, + enum iio_backend_data_source data); +int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan, + u64 sample_rate_hz); int devm_iio_backend_request_buffer(struct device *dev, struct iio_backend *back, struct iio_dev *indio_dev); +ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len); +ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, char *buf); +int iio_backend_extend_chan_spec(struct iio_dev *indio_dev, + struct iio_backend *back, + struct iio_chan_spec *chan); void *iio_backend_get_priv(const struct iio_backend *conv); struct iio_backend *devm_iio_backend_get(struct device *dev, const char *name); struct iio_backend * -- cgit v1.2.3 From 09415814cd1d0b90b898f81d6ad6a1c0a2e22d32 Mon Sep 17 00:00:00 2001 From: Nuno Sa Date: Fri, 26 Apr 2024 17:42:10 +0200 Subject: iio: backend: change docs padding Using tabs and maintaining the start of the docs aligned is a pain and may lead to lot's of unrelated changes when adding new members. Hence, let#s change things now and just have a simple space after the member name. Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240426-ad9467-new-features-v2-1-6361fc3ba1cc@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-backend.c | 76 +++++++++++++++++++------------------- include/linux/iio/backend.h | 38 +++++++++---------- 2 files changed, 57 insertions(+), 57 deletions(-) (limited to 'include/linux/iio/backend.h') diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c index f08ed6d70ae5..c27243e88462 100644 --- a/drivers/iio/industrialio-backend.c +++ b/drivers/iio/industrialio-backend.c @@ -115,8 +115,8 @@ static DEFINE_MUTEX(iio_back_lock); /** * iio_backend_chan_enable - Enable a backend channel - * @back: Backend device - * @chan: Channel number + * @back: Backend device + * @chan: Channel number * * RETURNS: * 0 on success, negative error number on failure. @@ -129,8 +129,8 @@ EXPORT_SYMBOL_NS_GPL(iio_backend_chan_enable, IIO_BACKEND); /** * iio_backend_chan_disable - Disable a backend channel - * @back: Backend device - * @chan: Channel number + * @back: Backend device + * @chan: Channel number * * RETURNS: * 0 on success, negative error number on failure. @@ -148,8 +148,8 @@ static void __iio_backend_disable(void *back) /** * devm_iio_backend_enable - Device managed backend enable - * @dev: Consumer device for the backend - * @back: Backend device + * @dev: Consumer device for the backend + * @back: Backend device * * RETURNS: * 0 on success, negative error number on failure. @@ -168,9 +168,9 @@ EXPORT_SYMBOL_NS_GPL(devm_iio_backend_enable, IIO_BACKEND); /** * iio_backend_data_format_set - Configure the channel data format - * @back: Backend device - * @chan: Channel number - * @data: Data format + * @back: Backend device + * @chan: Channel number + * @data: Data format * * Properly configure a channel with respect to the expected data format. A * @struct iio_backend_data_fmt must be passed with the settings. @@ -190,9 +190,9 @@ EXPORT_SYMBOL_NS_GPL(iio_backend_data_format_set, IIO_BACKEND); /** * iio_backend_data_source_set - Select data source - * @back: Backend device - * @chan: Channel number - * @data: Data source + * @back: Backend device + * @chan: Channel number + * @data: Data source * * A given backend may have different sources to stream/sync data. This allows * to choose that source. @@ -212,9 +212,9 @@ EXPORT_SYMBOL_NS_GPL(iio_backend_data_source_set, IIO_BACKEND); /** * iio_backend_set_sampling_freq - Set channel sampling rate - * @back: Backend device - * @chan: Channel number - * @sample_rate_hz: Sample rate + * @back: Backend device + * @chan: Channel number + * @sample_rate_hz: Sample rate * * RETURNS: * 0 on success, negative error number on failure. @@ -235,9 +235,9 @@ static void iio_backend_free_buffer(void *arg) /** * devm_iio_backend_request_buffer - Device managed buffer request - * @dev: Consumer device for the backend - * @back: Backend device - * @indio_dev: IIO device + * @dev: Consumer device for the backend + * @back: Backend device + * @indio_dev: IIO device * * Request an IIO buffer from the backend. The type of the buffer (typically * INDIO_BUFFER_HARDWARE) is up to the backend to decide. This is because, @@ -300,10 +300,10 @@ static struct iio_backend *iio_backend_from_indio_dev_parent(const struct device /** * iio_backend_ext_info_get - IIO ext_info read callback - * @indio_dev: IIO device - * @private: Data private to the driver - * @chan: IIO channel - * @buf: Buffer where to place the attribute data + * @indio_dev: IIO device + * @private: Data private to the driver + * @chan: IIO channel + * @buf: Buffer where to place the attribute data * * This helper is intended to be used by backends that extend an IIO channel * (through iio_backend_extend_chan_spec()) with extended info. In that case, @@ -335,11 +335,11 @@ EXPORT_SYMBOL_NS_GPL(iio_backend_ext_info_get, IIO_BACKEND); /** * iio_backend_ext_info_set - IIO ext_info write callback - * @indio_dev: IIO device - * @private: Data private to the driver - * @chan: IIO channel - * @buf: Buffer holding the sysfs attribute - * @len: Buffer length + * @indio_dev: IIO device + * @private: Data private to the driver + * @chan: IIO channel + * @buf: Buffer holding the sysfs attribute + * @len: Buffer length * * This helper is intended to be used by backends that extend an IIO channel * (trough iio_backend_extend_chan_spec()) with extended info. In that case, @@ -365,9 +365,9 @@ EXPORT_SYMBOL_NS_GPL(iio_backend_ext_info_set, IIO_BACKEND); /** * iio_backend_extend_chan_spec - Extend an IIO channel - * @indio_dev: IIO device - * @back: Backend device - * @chan: IIO channel + * @indio_dev: IIO device + * @back: Backend device + * @chan: IIO channel * * Some backends may have their own functionalities and hence capable of * extending a frontend's channel. @@ -449,8 +449,8 @@ static int __devm_iio_backend_get(struct device *dev, struct iio_backend *back) /** * devm_iio_backend_get - Device managed backend device get - * @dev: Consumer device for the backend - * @name: Backend name + * @dev: Consumer device for the backend + * @name: Backend name * * Get's the backend associated with @dev. * @@ -501,8 +501,8 @@ EXPORT_SYMBOL_NS_GPL(devm_iio_backend_get, IIO_BACKEND); /** * __devm_iio_backend_get_from_fwnode_lookup - Device managed fwnode backend device get - * @dev: Consumer device for the backend - * @fwnode: Firmware node of the backend device + * @dev: Consumer device for the backend + * @fwnode: Firmware node of the backend device * * Search the backend list for a device matching @fwnode. * This API should not be used and it's only present for preventing the first @@ -536,7 +536,7 @@ EXPORT_SYMBOL_NS_GPL(__devm_iio_backend_get_from_fwnode_lookup, IIO_BACKEND); /** * iio_backend_get_priv - Get driver private data - * @back: Backend device + * @back: Backend device */ void *iio_backend_get_priv(const struct iio_backend *back) { @@ -554,9 +554,9 @@ static void iio_backend_unregister(void *arg) /** * devm_iio_backend_register - Device managed backend device register - * @dev: Backend device being registered - * @ops: Backend ops - * @priv: Device private data + * @dev: Backend device being registered + * @ops: Backend ops + * @priv: Device private data * * @ops is mandatory. Not providing it results in -EINVAL. * diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h index 9d144631134d..e3e62f65db14 100644 --- a/include/linux/iio/backend.h +++ b/include/linux/iio/backend.h @@ -24,9 +24,9 @@ enum iio_backend_data_source { /** * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute - * @_name: Attribute name - * @_shared: Whether the attribute is shared between all channels - * @_what: Data private to the driver + * @_name: Attribute name + * @_shared: Whether the attribute is shared between all channels + * @_what: Data private to the driver */ #define IIO_BACKEND_EX_INFO(_name, _shared, _what) { \ .name = (_name), \ @@ -38,10 +38,10 @@ enum iio_backend_data_source { /** * struct iio_backend_data_fmt - Backend data format - * @type: Data type. - * @sign_extend: Bool to tell if the data is sign extended. - * @enable: Enable/Disable the data format module. If disabled, - * not formatting will happen. + * @type: Data type. + * @sign_extend: Bool to tell if the data is sign extended. + * @enable: Enable/Disable the data format module. If disabled, + * not formatting will happen. */ struct iio_backend_data_fmt { enum iio_backend_data_type type; @@ -51,18 +51,18 @@ struct iio_backend_data_fmt { /** * struct iio_backend_ops - operations structure for an iio_backend - * @enable: Enable backend. - * @disable: Disable backend. - * @chan_enable: Enable one channel. - * @chan_disable: Disable one channel. - * @data_format_set: Configure the data format for a specific channel. - * @data_source_set: Configure the data source for a specific channel. - * @set_sample_rate: Configure the sampling rate for a specific channel. - * @request_buffer: Request an IIO buffer. - * @free_buffer: Free an IIO buffer. - * @extend_chan_spec: Extend an IIO channel. - * @ext_info_set: Extended info setter. - * @ext_info_get: Extended info getter. + * @enable: Enable backend. + * @disable: Disable backend. + * @chan_enable: Enable one channel. + * @chan_disable: Disable one channel. + * @data_format_set: Configure the data format for a specific channel. + * @data_source_set: Configure the data source for a specific channel. + * @set_sample_rate: Configure the sampling rate for a specific channel. + * @request_buffer: Request an IIO buffer. + * @free_buffer: Free an IIO buffer. + * @extend_chan_spec: Extend an IIO channel. + * @ext_info_set: Extended info setter. + * @ext_info_get: Extended info getter. **/ struct iio_backend_ops { int (*enable)(struct iio_backend *back); -- cgit v1.2.3 From c66eabcc1ca64dbf20d0758ce210a85fa83f4b21 Mon Sep 17 00:00:00 2001 From: Nuno Sa Date: Fri, 26 Apr 2024 17:42:11 +0200 Subject: iio: backend: add API for interface tuning This is in preparation for supporting interface tuning in one for the devices using the axi-adc backend. The new added interfaces are all needed for that calibration: * iio_backend_test_pattern_set(); * iio_backend_chan_status(); * iio_backend_iodelay_set(); * iio_backend_data_sample_trigger(). Interface tuning is the process of going through a set of known points (typically by the frontend), change some clk or data delays (or both) and send/receive some known signal (so called test patterns in this change). The receiving end (either frontend or the backend) is responsible for validating the signal and see if it's good or not. The goal for all of this is to come up with ideal delays at the data interface level so we can have a proper, more reliable data transfer. Also note that for some devices we can change the sampling rate (which typically means changing some reference clock) and that can affect the data interface. In that case, it's import to run the tuning algorithm again as the values we had before may no longer be the best (or even valid) ones. Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240426-ad9467-new-features-v2-2-6361fc3ba1cc@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-backend.c | 86 ++++++++++++++++++++++++++++++++++++++ include/linux/iio/backend.h | 36 ++++++++++++++++ 2 files changed, 122 insertions(+) (limited to 'include/linux/iio/backend.h') diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c index c27243e88462..929aff4040ed 100644 --- a/drivers/iio/industrialio-backend.c +++ b/drivers/iio/industrialio-backend.c @@ -226,6 +226,92 @@ int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan, } EXPORT_SYMBOL_NS_GPL(iio_backend_set_sampling_freq, IIO_BACKEND); +/** + * iio_backend_test_pattern_set - Configure a test pattern + * @back: Backend device + * @chan: Channel number + * @pattern: Test pattern + * + * Configure a test pattern on the backend. This is typically used for + * calibrating the timings on the data digital interface. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_test_pattern_set(struct iio_backend *back, + unsigned int chan, + enum iio_backend_test_pattern pattern) +{ + if (pattern >= IIO_BACKEND_TEST_PATTERN_MAX) + return -EINVAL; + + return iio_backend_op_call(back, test_pattern_set, chan, pattern); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_test_pattern_set, IIO_BACKEND); + +/** + * iio_backend_chan_status - Get the channel status + * @back: Backend device + * @chan: Channel number + * @error: Error indication + * + * Get the current state of the backend channel. Typically used to check if + * there were any errors sending/receiving data. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_chan_status(struct iio_backend *back, unsigned int chan, + bool *error) +{ + return iio_backend_op_call(back, chan_status, chan, error); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_chan_status, IIO_BACKEND); + +/** + * iio_backend_iodelay_set - Set digital I/O delay + * @back: Backend device + * @lane: Lane number + * @taps: Number of taps + * + * Controls delays on sending/receiving data. One usecase for this is to + * calibrate the data digital interface so we get the best results when + * transferring data. Note that @taps has no unit since the actual delay per tap + * is very backend specific. Hence, frontend devices typically should go through + * an array of @taps (the size of that array should typically match the size of + * calibration points on the frontend device) and call this API. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_iodelay_set(struct iio_backend *back, unsigned int lane, + unsigned int taps) +{ + return iio_backend_op_call(back, iodelay_set, lane, taps); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_iodelay_set, IIO_BACKEND); + +/** + * iio_backend_data_sample_trigger - Control when to sample data + * @back: Backend device + * @trigger: Data trigger + * + * Mostly useful for input backends. Configures the backend for when to sample + * data (eg: rising vs falling edge). + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_data_sample_trigger(struct iio_backend *back, + enum iio_backend_sample_trigger trigger) +{ + if (trigger >= IIO_BACKEND_SAMPLE_TRIGGER_MAX) + return -EINVAL; + + return iio_backend_op_call(back, data_sample_trigger, trigger); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_data_sample_trigger, IIO_BACKEND); + static void iio_backend_free_buffer(void *arg) { struct iio_backend_buffer_pair *pair = arg; diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h index e3e62f65db14..8099759d7242 100644 --- a/include/linux/iio/backend.h +++ b/include/linux/iio/backend.h @@ -49,6 +49,20 @@ struct iio_backend_data_fmt { bool enable; }; +/* vendor specific from 32 */ +enum iio_backend_test_pattern { + IIO_BACKEND_NO_TEST_PATTERN, + /* modified prbs9 */ + IIO_BACKEND_ADI_PRBS_9A = 32, + IIO_BACKEND_TEST_PATTERN_MAX +}; + +enum iio_backend_sample_trigger { + IIO_BACKEND_SAMPLE_TRIGGER_EDGE_FALLING, + IIO_BACKEND_SAMPLE_TRIGGER_EDGE_RISING, + IIO_BACKEND_SAMPLE_TRIGGER_MAX +}; + /** * struct iio_backend_ops - operations structure for an iio_backend * @enable: Enable backend. @@ -58,6 +72,10 @@ struct iio_backend_data_fmt { * @data_format_set: Configure the data format for a specific channel. * @data_source_set: Configure the data source for a specific channel. * @set_sample_rate: Configure the sampling rate for a specific channel. + * @test_pattern_set: Configure a test pattern. + * @chan_status: Get the channel status. + * @iodelay_set: Set digital I/O delay. + * @data_sample_trigger: Control when to sample data. * @request_buffer: Request an IIO buffer. * @free_buffer: Free an IIO buffer. * @extend_chan_spec: Extend an IIO channel. @@ -75,6 +93,15 @@ struct iio_backend_ops { enum iio_backend_data_source data); int (*set_sample_rate)(struct iio_backend *back, unsigned int chan, u64 sample_rate_hz); + int (*test_pattern_set)(struct iio_backend *back, + unsigned int chan, + enum iio_backend_test_pattern pattern); + int (*chan_status)(struct iio_backend *back, unsigned int chan, + bool *error); + int (*iodelay_set)(struct iio_backend *back, unsigned int chan, + unsigned int taps); + int (*data_sample_trigger)(struct iio_backend *back, + enum iio_backend_sample_trigger trigger); struct iio_buffer *(*request_buffer)(struct iio_backend *back, struct iio_dev *indio_dev); void (*free_buffer)(struct iio_backend *back, @@ -97,6 +124,15 @@ int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan, enum iio_backend_data_source data); int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan, u64 sample_rate_hz); +int iio_backend_test_pattern_set(struct iio_backend *back, + unsigned int chan, + enum iio_backend_test_pattern pattern); +int iio_backend_chan_status(struct iio_backend *back, unsigned int chan, + bool *error); +int iio_backend_iodelay_set(struct iio_backend *back, unsigned int lane, + unsigned int taps); +int iio_backend_data_sample_trigger(struct iio_backend *back, + enum iio_backend_sample_trigger trigger); int devm_iio_backend_request_buffer(struct device *dev, struct iio_backend *back, struct iio_dev *indio_dev); -- cgit v1.2.3