1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /* vim: set ts=8 sw=8 noet tw=80 nowrap: */
3 /*
4 * comedi/drivers/ni_routes.h
5 * Route information for NI boards.
6 *
7 * COMEDI - Linux Control and Measurement Device Interface
8 * Copyright (C) 2016 Spencer E. Olson <olsonse@umich.edu>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 */
20
21 #ifndef _COMEDI_DRIVERS_NI_ROUTES_H
22 #define _COMEDI_DRIVERS_NI_ROUTES_H
23
24 #include <linux/types.h>
25 #include <linux/errno.h>
26
27 #ifndef NI_ROUTE_VALUE_EXTERNAL_CONVERSION
28 #include <linux/bitops.h>
29 #endif
30
31 #include "../comedi.h"
32
33 /**
34 * struct ni_route_set - Set of destinations with a common source.
35 * @dest: Destination of all sources in this route set.
36 * @n_src: Number of sources for this route set.
37 * @src: List of sources that all map to the same destination.
38 */
39 struct ni_route_set {
40 int dest;
41 int n_src;
42 int *src;
43 };
44
45 /**
46 * struct ni_device_routes - List of all src->dest sets for a particular device.
47 * @device: Name of board/device (e.g. pxi-6733).
48 * @n_route_sets: Number of route sets that are valid for this device.
49 * @routes: List of route sets that are valid for this device.
50 */
51 struct ni_device_routes {
52 const char *device;
53 int n_route_sets;
54 struct ni_route_set *routes;
55 };
56
57 /**
58 * struct ni_route_tables - Register values and valid routes for a device.
59 * @valid_routes: Pointer to a all valid route sets for a single device.
60 * @route_values: Pointer to register values for all routes for the family to
61 * which the device belongs.
62 *
63 * Link to the valid src->dest routes and the register values used to assign
64 * such routes for that particular device.
65 */
66 struct ni_route_tables {
67 const struct ni_device_routes *valid_routes;
68 const u8 *route_values;
69 };
70
71 /*
72 * ni_assign_device_routes() - Assign the proper lookup table for NI signal
73 * routing to the specified NI device.
74 *
75 * Return: -ENODATA if assignment was not successful; 0 if successful.
76 */
77 int ni_assign_device_routes(const char *device_family,
78 const char *board_name,
79 struct ni_route_tables *tables);
80
81 /*
82 * ni_find_route_set() - Finds the proper route set with the specified
83 * destination.
84 * @destination: Destination of which to search for the route set.
85 * @valid_routes: Pointer to device routes within which to search.
86 *
87 * Return: NULL if no route_set is found with the specified @destination;
88 * otherwise, a pointer to the route_set if found.
89 */
90 const struct ni_route_set *
91 ni_find_route_set(const int destination,
92 const struct ni_device_routes *valid_routes);
93
94 /*
95 * ni_route_set_has_source() - Determines whether the given source is in
96 * included given route_set.
97 *
98 * Return: true if found; false otherwise.
99 */
100 bool ni_route_set_has_source(const struct ni_route_set *routes, const int src);
101
102 /*
103 * ni_route_to_register() - Validates and converts the specified signal route
104 * (src-->dest) to the value used at the appropriate
105 * register.
106 * @src: global-identifier for route source
107 * @dest: global-identifier for route destination
108 * @tables: pointer to relevant set of routing tables.
109 *
110 * Generally speaking, most routes require the first six bits and a few require
111 * 7 bits. Special handling is given for the return value when the route is to
112 * be handled by the RTSI sub-device. In this case, the returned register may
113 * not be sufficient to define the entire route path, but rather may only
114 * indicate the intermediate route. For example, if the route must go through
115 * the RGOUT0 pin, the (src->RGOUT0) register value will be returned.
116 * Similarly, if the route must go through the NI_RTSI_BRD lines, the BIT(6)
117 * will be set:
118 *
119 * if route does not need RTSI_BRD lines:
120 * bits 0:7 : register value
121 * for a route that must go through RGOUT0 pin, this will be equal
122 * to the (src->RGOUT0) register value.
123 * else: * route is (src->RTSI_BRD(x), RTSI_BRD(x)->TRIGGER_LINE(i)) *
124 * bits 0:5 : zero
125 * bits 6 : set to 1
126 * bits 7:7 : zero
127 *
128 * Return: register value to be used for source at destination with special
129 * cases given above; Otherwise, -1 if the specified route is not valid for
130 * this particular device.
131 */
132 s8 ni_route_to_register(const int src, const int dest,
133 const struct ni_route_tables *tables);
134
135 static inline bool ni_rtsi_route_requires_mux(s8 value)
136 {
137 return value & BIT(6);
138 }
139
140 /*
141 * ni_lookup_route_register() - Look up a register value for a particular route
142 * without checking whether the route is valid for
143 * the particular device.
144 * @src: global-identifier for route source
145 * @dest: global-identifier for route destination
146 * @tables: pointer to relevant set of routing tables.
147 *
148 * Return: -EINVAL if the specified route is not valid for this device family.
149 */
150 s8 ni_lookup_route_register(int src, int dest,
151 const struct ni_route_tables *tables);
152
153 /**
154 * route_is_valid() - Determines whether the specified signal route (src-->dest)
155 * is valid for the given NI comedi_device.
156 * @src: global-identifier for route source
157 * @dest: global-identifier for route destination
158 * @tables: pointer to relevant set of routing tables.
159 *
160 * Return: True if the route is valid, otherwise false.
161 */
162 static inline bool route_is_valid(const int src, const int dest,
163 const struct ni_route_tables *tables)
164 {
165 return ni_route_to_register(src, dest, tables) >= 0;
166 }
167
168 /*
169 * ni_is_cmd_dest() - Determine whether the given destination is only
170 * configurable via a comedi_cmd struct.
171 * @dest: Destination to test.
172 */
173 bool ni_is_cmd_dest(int dest);
174
175 static inline bool channel_is_pfi(int channel)
176 {
177 return NI_PFI(0) <= channel && channel <= NI_PFI(-1);
178 }
179
180 static inline bool channel_is_rtsi(int channel)
181 {
182 return TRIGGER_LINE(0) <= channel && channel <= TRIGGER_LINE(-1);
183 }
184
185 static inline bool channel_is_ctr(int channel)
186 {
187 return channel >= NI_COUNTER_NAMES_BASE &&
188 channel <= NI_COUNTER_NAMES_MAX;
189 }
190
191 /*
192 * ni_count_valid_routes() - Count the number of valid routes.
193 * @tables: Routing tables for which to count all valid routes.
194 */
195 unsigned int ni_count_valid_routes(const struct ni_route_tables *tables);
196
197 /*
198 * ni_get_valid_routes() - Implements INSN_DEVICE_CONFIG_GET_ROUTES.
199 * @tables: pointer to relevant set of routing tables.
200 * @n_pairs: Number of pairs for which memory is allocated by the user. If
201 * the user specifies '0', only the number of available pairs is
202 * returned.
203 * @pair_data: Pointer to memory allocated to return pairs back to user. Each
204 * even, odd indexed member of this array will hold source,
205 * destination of a route pair respectively.
206 *
207 * Return: the number of valid routes if n_pairs == 0; otherwise, the number of
208 * valid routes copied.
209 */
210 unsigned int ni_get_valid_routes(const struct ni_route_tables *tables,
211 unsigned int n_pairs,
212 unsigned int *pair_data);
213
214 /*
215 * ni_sort_device_routes() - Sort the list of valid device signal routes in
216 * preparation for use.
217 * @valid_routes: pointer to ni_device_routes struct to sort.
218 */
219 void ni_sort_device_routes(struct ni_device_routes *valid_routes);
220
221 /*
222 * ni_find_route_source() - Finds the signal source corresponding to a signal
223 * route (src-->dest) of the specified routing register
224 * value and the specified route destination on the
225 * specified device.
226 *
227 * Note that this function does _not_ validate the source based on device
228 * routes.
229 *
230 * Return: The NI signal value (e.g. NI_PFI(0) or PXI_Clk10) if found.
231 * If the source was not found (i.e. the register value is not
232 * valid for any routes to the destination), -EINVAL is returned.
233 */
234 int ni_find_route_source(const u8 src_sel_reg_value, const int dest,
235 const struct ni_route_tables *tables);
236
237 /**
238 * route_register_is_valid() - Determines whether the register value for the
239 * specified route destination on the specified
240 * device is valid.
241 */
242 static inline bool route_register_is_valid(const u8 src_sel_reg_value,
243 const int dest,
244 const struct ni_route_tables *tables)
245 {
246 return ni_find_route_source(src_sel_reg_value, dest, tables) >= 0;
247 }
248
249 /**
250 * ni_get_reg_value_roffs() - Determines the proper register value for a
251 * particular valid NI signal/terminal route.
252 * @src: Either a direct register value or one of NI_* signal names.
253 * @dest: global-identifier for route destination
254 * @tables: pointer to relevant set of routing tables.
255 * @direct_reg_offset:
256 * Compatibility compensation argument. This argument allows us to
257 * arbitrarily apply an offset to src if src is a direct register
258 * value reference. This is necessary to be compatible with
259 * definitions of register values as previously exported directly
260 * to user space.
261 *
262 * Return: the register value (>0) to be used at the destination if the src is
263 * valid for the given destination; -1 otherwise.
264 */
265 static inline s8 ni_get_reg_value_roffs(int src, const int dest,
266 const struct ni_route_tables *tables,
267 const int direct_reg_offset)
268 {
269 if (src < NI_NAMES_BASE) {
270 src += direct_reg_offset;
271 /*
272 * In this case, the src is expected to actually be a register
273 * value.
274 */
275 if (route_register_is_valid(src, dest, tables))
276 return src;
277 return -1;
278 }
279
280 /*
281 * Otherwise, the src is expected to be one of the abstracted NI
282 * signal/terminal names.
283 */
284 return ni_route_to_register(src, dest, tables);
285 }
286
287 static inline int ni_get_reg_value(const int src, const int dest,
288 const struct ni_route_tables *tables)
289 {
290 return ni_get_reg_value_roffs(src, dest, tables, 0);
291 }
292
293 /**
294 * ni_check_trigger_arg_roffs() - Checks the trigger argument (*_arg) of an NI
295 * device to ensure that the *_arg value
296 * corresponds to _either_ a valid register value
297 * to define a trigger source, _or_ a valid NI
298 * signal/terminal name that has a valid route to
299 * the destination on the particular device.
300 * @src: Either a direct register value or one of NI_* signal names.
301 * @dest: global-identifier for route destination
302 * @tables: pointer to relevant set of routing tables.
303 * @direct_reg_offset:
304 * Compatibility compensation argument. This argument allows us to
305 * arbitrarily apply an offset to src if src is a direct register
306 * value reference. This is necessary to be compatible with
307 * definitions of register values as previously exported directly
308 * to user space.
309 *
310 * Return: 0 if the src (either register value or NI signal/terminal name) is
311 * valid for the destination; -EINVAL otherwise.
312 */
313 static inline
314 int ni_check_trigger_arg_roffs(int src, const int dest,
315 const struct ni_route_tables *tables,
316 const int direct_reg_offset)
317 {
318 if (ni_get_reg_value_roffs(src, dest, tables, direct_reg_offset) < 0)
319 return -EINVAL;
320 return 0;
321 }
322
323 static inline int ni_check_trigger_arg(const int src, const int dest,
324 const struct ni_route_tables *tables)
325 {
326 return ni_check_trigger_arg_roffs(src, dest, tables, 0);
327 }
328
329 #endif /* _COMEDI_DRIVERS_NI_ROUTES_H */