From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nuno Sa Date: Fri, 19 Apr 2024 17:36:44 +0200 Subject: [PATCH 1/8] iio: backend: add API for interface tuning MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240419-ad9467-new-features-v1-1-3e7628ff6d5e@analog.com> References: <20240419-ad9467-new-features-v1-0-3e7628ff6d5e@analog.com> In-Reply-To: <20240419-ad9467-new-features-v1-0-3e7628ff6d5e@analog.com> To: linux-iio@vger.kernel.org, devicetree@vger.kernel.org Cc: Jonathan Cameron , Alexandru Ardelean , Lars-Peter Clausen , Michael Hennerich , Jonathan Cameron , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Olivier Moysan , Nuno Sa X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1713541010; l=7623; i=nuno.sa@analog.com; s=20231116; h=from:subject:message-id; bh=UN9oAzFiKwoRseAjq8NdAF3wlTP1db9PUGQ2DM4QoRQ=; b=zrKmro4hJnByJECx3y8HxHJVzShYKzBsLW3PXbD9QqFSpirl9Mp95kNO7C5vmEUua+V078crW O+d96m0jpB5DkKcLVjxjWfjs6oMx8uMb20NKtTmFRMCxYYrFZTcNJMF X-Developer-Key: i=nuno.sa@analog.com; a=ed25519; pk=3NQwYA013OUYZsmDFBf8rmyyr5iQlxV/9H4/Df83o1E= X-Endpoint-Received: by B4 Relay for nuno.sa@analog.com/20231116 with auth_id=100 List-Id: B4 Relay Submissions 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(). Signed-off-by: Nuno Sa --- drivers/iio/industrialio-backend.c | 86 ++++++++++++++++++++++++++++++++++++++ include/linux/iio/backend.h | 57 +++++++++++++++++++++---- 2 files changed, 136 insertions(+), 7 deletions(-) diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c index 2fea2bbbe47fd..45eea3b725a35 100644 --- a/drivers/iio/industrialio-backend.c +++ b/drivers/iio/industrialio-backend.c @@ -186,6 +186,92 @@ int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan, } EXPORT_SYMBOL_NS_GPL(iio_backend_data_format_set, IIO_BACKEND); +/** + * iio_backend_test_pattern_set - Configure a test pattern + * @back: Backend device + * @chan: Channel number + * @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 + * @status: Channel status + * + * 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, + struct iio_backend_chan_status *status) +{ + return iio_backend_op_call(back, chan_status, chan, status); +} +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 + * @tap: 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 @tap 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 tap) +{ + return iio_backend_op_call(back, iodelay_set, lane, tap); +} +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 a6d79381866ec..ad793fe0d78c2 100644 --- a/include/linux/iio/backend.h +++ b/include/linux/iio/backend.h @@ -15,6 +15,19 @@ enum iio_backend_data_type { IIO_BACKEND_DATA_TYPE_MAX }; +/* vendor specific from 32 */ +enum iio_backend_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_data_fmt - Backend data format * @type: Data type. @@ -28,15 +41,27 @@ struct iio_backend_data_fmt { bool enable; }; +/** + * struct iio_backend_chan_status - Backend channel status + * @errors: Errors occurred when sending/receiving data. + */ +struct iio_backend_chan_status { + bool errors; +}; + /** * 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. - * @request_buffer: Request an IIO buffer. - * @free_buffer: Free an IIO buffer. + * @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. + * @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. **/ struct iio_backend_ops { int (*enable)(struct iio_backend *back); @@ -45,6 +70,15 @@ 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 (*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, + struct iio_backend_chan_status *status); + int (*iodelay_set)(struct iio_backend *back, unsigned int chan, + unsigned int tap); + 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, @@ -56,6 +90,15 @@ 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_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, + struct iio_backend_chan_status *status); +int iio_backend_iodelay_set(struct iio_backend *back, unsigned int lane, + unsigned int tap); +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); -- 2.44.0