xref: /linux/include/linux/iio/backend.h (revision cb4eb6771c0f8fd1c52a8f6fdec7762fb087380a)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _IIO_BACKEND_H_
3 #define _IIO_BACKEND_H_
4 
5 #include <linux/types.h>
6 #include <linux/iio/iio.h>
7 
8 struct iio_chan_spec;
9 struct fwnode_handle;
10 struct iio_backend;
11 struct device;
12 struct iio_dev;
13 
14 enum iio_backend_data_type {
15 	IIO_BACKEND_TWOS_COMPLEMENT,
16 	IIO_BACKEND_OFFSET_BINARY,
17 	IIO_BACKEND_DATA_UNSIGNED,
18 	IIO_BACKEND_DATA_TYPE_MAX
19 };
20 
21 enum iio_backend_data_source {
22 	IIO_BACKEND_INTERNAL_CONTINUOUS_WAVE,
23 	IIO_BACKEND_EXTERNAL,
24 	IIO_BACKEND_INTERNAL_RAMP_16BIT,
25 	IIO_BACKEND_DATA_SOURCE_MAX
26 };
27 
28 #define iio_backend_debugfs_ptr(ptr)	PTR_IF(IS_ENABLED(CONFIG_DEBUG_FS), ptr)
29 
30 /**
31  * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute
32  * @_name: Attribute name
33  * @_shared: Whether the attribute is shared between all channels
34  * @_what: Data private to the driver
35  */
36 #define IIO_BACKEND_EX_INFO(_name, _shared, _what) {	\
37 	.name = (_name),				\
38 	.shared = (_shared),				\
39 	.read =  iio_backend_ext_info_get,		\
40 	.write = iio_backend_ext_info_set,		\
41 	.private = (_what),				\
42 }
43 
44 /**
45  * struct iio_backend_data_fmt - Backend data format
46  * @type: Data type.
47  * @sign_extend: Bool to tell if the data is sign extended.
48  * @enable: Enable/Disable the data format module. If disabled,
49  *	    not formatting will happen.
50  */
51 struct iio_backend_data_fmt {
52 	enum iio_backend_data_type type;
53 	bool sign_extend;
54 	bool enable;
55 };
56 
57 /* vendor specific from 32 */
58 enum iio_backend_test_pattern {
59 	IIO_BACKEND_NO_TEST_PATTERN,
60 	/* modified prbs9 */
61 	IIO_BACKEND_ADI_PRBS_9A = 32,
62 	/* modified prbs23 */
63 	IIO_BACKEND_ADI_PRBS_23A,
64 	IIO_BACKEND_TEST_PATTERN_MAX
65 };
66 
67 enum iio_backend_sample_trigger {
68 	IIO_BACKEND_SAMPLE_TRIGGER_EDGE_FALLING,
69 	IIO_BACKEND_SAMPLE_TRIGGER_EDGE_RISING,
70 	IIO_BACKEND_SAMPLE_TRIGGER_MAX
71 };
72 
73 enum iio_backend_interface_type {
74 	IIO_BACKEND_INTERFACE_SERIAL_LVDS,
75 	IIO_BACKEND_INTERFACE_SERIAL_CMOS,
76 	IIO_BACKEND_INTERFACE_MAX
77 };
78 
79 enum iio_backend_filter_type {
80 	IIO_BACKEND_FILTER_TYPE_DISABLED,
81 	IIO_BACKEND_FILTER_TYPE_SINC1,
82 	IIO_BACKEND_FILTER_TYPE_SINC5,
83 	IIO_BACKEND_FILTER_TYPE_SINC5_PLUS_COMP,
84 	IIO_BACKEND_FILTER_TYPE_MAX
85 };
86 
87 /**
88  * enum iio_backend_capabilities - Backend capabilities
89  * Backend capabilities can be used by frontends to check if a given
90  * functionality is supported by the backend. This is useful for frontend
91  * devices which are expected to work with alternative backend
92  * implementations. Capabilities are loosely coupled with operations,
93  * meaning that a capability requires certain operations to be implemented
94  * by the backend. A capability might be mapped to a single operation or
95  * multiple operations.
96  *
97  * @IIO_BACKEND_CAP_CALIBRATION: Backend supports digital interface
98  * calibration. Calibration procedure is device specific.
99  * @IIO_BACKEND_CAP_BUFFER: Support for IIO buffer interface.
100  * @IIO_BACKEND_CAP_ENABLE: Backend can be explicitly enabled/disabled.
101  */
102 enum iio_backend_capabilities {
103 	IIO_BACKEND_CAP_CALIBRATION = BIT(0),
104 	IIO_BACKEND_CAP_BUFFER = BIT(1),
105 	IIO_BACKEND_CAP_ENABLE = BIT(2),
106 };
107 
108 /**
109  * struct iio_backend_ops - operations structure for an iio_backend
110  * @enable: Enable backend.
111  * @disable: Disable backend.
112  * @chan_enable: Enable one channel.
113  * @chan_disable: Disable one channel.
114  * @data_format_set: Configure the data format for a specific channel.
115  * @data_source_set: Configure the data source for a specific channel.
116  * @data_source_get: Data source getter for a specific channel.
117  * @set_sample_rate: Configure the sampling rate for a specific channel.
118  * @test_pattern_set: Configure a test pattern.
119  * @chan_status: Get the channel status.
120  * @iodelay_set: Set digital I/O delay.
121  * @data_sample_trigger: Control when to sample data.
122  * @request_buffer: Request an IIO buffer.
123  * @free_buffer: Free an IIO buffer.
124  * @extend_chan_spec: Extend an IIO channel.
125  * @ext_info_set: Extended info setter.
126  * @ext_info_get: Extended info getter.
127  * @interface_type_get: Interface type.
128  * @data_size_set: Data size.
129  * @oversampling_ratio_set: Set Oversampling ratio.
130  * @read_raw: Read a channel attribute from a backend device
131  * @debugfs_print_chan_status: Print channel status into a buffer.
132  * @debugfs_reg_access: Read or write register value of backend.
133  * @filter_type_set: Set filter type.
134  * @interface_data_align: Perform the data alignment process.
135  * @num_lanes_set: Set the number of lanes enabled.
136  * @ddr_enable: Enable interface DDR (Double Data Rate) mode.
137  * @ddr_disable: Disable interface DDR (Double Data Rate) mode.
138  * @data_stream_enable: Enable data stream.
139  * @data_stream_disable: Disable data stream.
140  * @data_transfer_addr: Set data address.
141  **/
142 struct iio_backend_ops {
143 	int (*enable)(struct iio_backend *back);
144 	void (*disable)(struct iio_backend *back);
145 	int (*chan_enable)(struct iio_backend *back, unsigned int chan);
146 	int (*chan_disable)(struct iio_backend *back, unsigned int chan);
147 	int (*data_format_set)(struct iio_backend *back, unsigned int chan,
148 			       const struct iio_backend_data_fmt *data);
149 	int (*data_source_set)(struct iio_backend *back, unsigned int chan,
150 			       enum iio_backend_data_source data);
151 	int (*data_source_get)(struct iio_backend *back, unsigned int chan,
152 			       enum iio_backend_data_source *data);
153 	int (*set_sample_rate)(struct iio_backend *back, unsigned int chan,
154 			       u64 sample_rate_hz);
155 	int (*test_pattern_set)(struct iio_backend *back,
156 				unsigned int chan,
157 				enum iio_backend_test_pattern pattern);
158 	int (*chan_status)(struct iio_backend *back, unsigned int chan,
159 			   bool *error);
160 	int (*iodelay_set)(struct iio_backend *back, unsigned int chan,
161 			   unsigned int taps);
162 	int (*data_sample_trigger)(struct iio_backend *back,
163 				   enum iio_backend_sample_trigger trigger);
164 	struct iio_buffer *(*request_buffer)(struct iio_backend *back,
165 					     struct iio_dev *indio_dev);
166 	void (*free_buffer)(struct iio_backend *back,
167 			    struct iio_buffer *buffer);
168 	int (*extend_chan_spec)(struct iio_backend *back,
169 				struct iio_chan_spec *chan);
170 	int (*ext_info_set)(struct iio_backend *back, uintptr_t private,
171 			    const struct iio_chan_spec *chan,
172 			    const char *buf, size_t len);
173 	int (*ext_info_get)(struct iio_backend *back, uintptr_t private,
174 			    const struct iio_chan_spec *chan, char *buf);
175 	int (*interface_type_get)(struct iio_backend *back,
176 				  enum iio_backend_interface_type *type);
177 	int (*data_size_set)(struct iio_backend *back, unsigned int size);
178 	int (*oversampling_ratio_set)(struct iio_backend *back,
179 				      unsigned int chan, unsigned int ratio);
180 	int (*read_raw)(struct iio_backend *back,
181 			struct iio_chan_spec const *chan, int *val, int *val2,
182 			long mask);
183 	int (*debugfs_print_chan_status)(struct iio_backend *back,
184 					 unsigned int chan, char *buf,
185 					 size_t len);
186 	int (*debugfs_reg_access)(struct iio_backend *back, unsigned int reg,
187 				  unsigned int writeval, unsigned int *readval);
188 	int (*filter_type_set)(struct iio_backend *back,
189 			       enum iio_backend_filter_type type);
190 	int (*interface_data_align)(struct iio_backend *back, u32 timeout_us);
191 	int (*num_lanes_set)(struct iio_backend *back, unsigned int num_lanes);
192 	int (*ddr_enable)(struct iio_backend *back);
193 	int (*ddr_disable)(struct iio_backend *back);
194 	int (*data_stream_enable)(struct iio_backend *back);
195 	int (*data_stream_disable)(struct iio_backend *back);
196 	int (*data_transfer_addr)(struct iio_backend *back, u32 address);
197 };
198 
199 /**
200  * struct iio_backend_info - info structure for an iio_backend
201  * @name: Backend name.
202  * @ops: Backend operations.
203  * @caps: Backend capabilities. (bitmask of enum iio_backend_capabilities).
204  */
205 struct iio_backend_info {
206 	const char *name;
207 	const struct iio_backend_ops *ops;
208 	u32 caps;
209 };
210 
211 int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan);
212 int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan);
213 int devm_iio_backend_enable(struct device *dev, struct iio_backend *back);
214 int iio_backend_enable(struct iio_backend *back);
215 void iio_backend_disable(struct iio_backend *back);
216 int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan,
217 				const struct iio_backend_data_fmt *data);
218 int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan,
219 				enum iio_backend_data_source data);
220 int iio_backend_data_source_get(struct iio_backend *back, unsigned int chan,
221 				enum iio_backend_data_source *data);
222 int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan,
223 				  u64 sample_rate_hz);
224 int iio_backend_test_pattern_set(struct iio_backend *back,
225 				 unsigned int chan,
226 				 enum iio_backend_test_pattern pattern);
227 int iio_backend_chan_status(struct iio_backend *back, unsigned int chan,
228 			    bool *error);
229 int iio_backend_iodelay_set(struct iio_backend *back, unsigned int lane,
230 			    unsigned int taps);
231 int iio_backend_data_sample_trigger(struct iio_backend *back,
232 				    enum iio_backend_sample_trigger trigger);
233 int devm_iio_backend_request_buffer(struct device *dev,
234 				    struct iio_backend *back,
235 				    struct iio_dev *indio_dev);
236 int iio_backend_filter_type_set(struct iio_backend *back,
237 				enum iio_backend_filter_type type);
238 int iio_backend_interface_data_align(struct iio_backend *back, u32 timeout_us);
239 int iio_backend_num_lanes_set(struct iio_backend *back, unsigned int num_lanes);
240 int iio_backend_ddr_enable(struct iio_backend *back);
241 int iio_backend_ddr_disable(struct iio_backend *back);
242 int iio_backend_data_stream_enable(struct iio_backend *back);
243 int iio_backend_data_stream_disable(struct iio_backend *back);
244 int iio_backend_data_transfer_addr(struct iio_backend *back, u32 address);
245 ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private,
246 				 const struct iio_chan_spec *chan,
247 				 const char *buf, size_t len);
248 ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private,
249 				 const struct iio_chan_spec *chan, char *buf);
250 int iio_backend_interface_type_get(struct iio_backend *back,
251 				   enum iio_backend_interface_type *type);
252 int iio_backend_data_size_set(struct iio_backend *back, unsigned int size);
253 int iio_backend_oversampling_ratio_set(struct iio_backend *back,
254 				       unsigned int chan,
255 				       unsigned int ratio);
256 int iio_backend_read_raw(struct iio_backend *back,
257 			 struct iio_chan_spec const *chan, int *val, int *val2,
258 			 long mask);
259 int iio_backend_extend_chan_spec(struct iio_backend *back,
260 				 struct iio_chan_spec *chan);
261 bool iio_backend_has_caps(struct iio_backend *back, u32 caps);
262 void *iio_backend_get_priv(const struct iio_backend *conv);
263 struct iio_backend *devm_iio_backend_get(struct device *dev, const char *name);
264 struct iio_backend *devm_iio_backend_fwnode_get(struct device *dev,
265 						const char *name,
266 						struct fwnode_handle *fwnode);
267 struct iio_backend *
268 __devm_iio_backend_get_from_fwnode_lookup(struct device *dev,
269 					  struct fwnode_handle *fwnode);
270 
271 int devm_iio_backend_register(struct device *dev,
272 			      const struct iio_backend_info *info, void *priv);
273 
iio_backend_read_scale(struct iio_backend * back,struct iio_chan_spec const * chan,int * val,int * val2)274 static inline int iio_backend_read_scale(struct iio_backend *back,
275 					 struct iio_chan_spec const *chan,
276 					 int *val, int *val2)
277 {
278 	return iio_backend_read_raw(back, chan, val, val2, IIO_CHAN_INFO_SCALE);
279 }
280 
iio_backend_read_offset(struct iio_backend * back,struct iio_chan_spec const * chan,int * val,int * val2)281 static inline int iio_backend_read_offset(struct iio_backend *back,
282 					  struct iio_chan_spec const *chan,
283 					  int *val, int *val2)
284 {
285 	return iio_backend_read_raw(back, chan, val, val2,
286 				    IIO_CHAN_INFO_OFFSET);
287 }
288 
289 ssize_t iio_backend_debugfs_print_chan_status(struct iio_backend *back,
290 					      unsigned int chan, char *buf,
291 					      size_t len);
292 void iio_backend_debugfs_add(struct iio_backend *back,
293 			     struct iio_dev *indio_dev);
294 #endif
295