1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2021-2022, Intel Corporation. */
3
4 #include "ice.h"
5 #include "ice_lib.h"
6
7 /**
8 * ice_gnss_do_write - Write data to internal GNSS receiver
9 * @pf: board private structure
10 * @buf: command buffer
11 * @size: command buffer size
12 *
13 * Write UBX command data to the GNSS receiver
14 *
15 * Return:
16 * * number of bytes written - success
17 * * negative - error code
18 */
19 static int
ice_gnss_do_write(struct ice_pf * pf,const unsigned char * buf,unsigned int size)20 ice_gnss_do_write(struct ice_pf *pf, const unsigned char *buf, unsigned int size)
21 {
22 struct ice_aqc_link_topo_addr link_topo;
23 struct ice_hw *hw = &pf->hw;
24 unsigned int offset = 0;
25 int err = 0;
26
27 memset(&link_topo, 0, sizeof(struct ice_aqc_link_topo_addr));
28 link_topo.topo_params.index = ICE_E810T_GNSS_I2C_BUS;
29 link_topo.topo_params.node_type_ctx |=
30 FIELD_PREP(ICE_AQC_LINK_TOPO_NODE_CTX_M,
31 ICE_AQC_LINK_TOPO_NODE_CTX_OVERRIDE);
32
33 /* It's not possible to write a single byte to u-blox.
34 * Write all bytes in a loop until there are 6 or less bytes left. If
35 * there are exactly 6 bytes left, the last write would be only a byte.
36 * In this case, do 4+2 bytes writes instead of 5+1. Otherwise, do the
37 * last 2 to 5 bytes write.
38 */
39 while (size - offset > ICE_GNSS_UBX_WRITE_BYTES + 1) {
40 err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
41 cpu_to_le16(buf[offset]),
42 ICE_MAX_I2C_WRITE_BYTES,
43 &buf[offset + 1], NULL);
44 if (err)
45 goto err_out;
46
47 offset += ICE_GNSS_UBX_WRITE_BYTES;
48 }
49
50 /* Single byte would be written. Write 4 bytes instead of 5. */
51 if (size - offset == ICE_GNSS_UBX_WRITE_BYTES + 1) {
52 err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
53 cpu_to_le16(buf[offset]),
54 ICE_MAX_I2C_WRITE_BYTES - 1,
55 &buf[offset + 1], NULL);
56 if (err)
57 goto err_out;
58
59 offset += ICE_GNSS_UBX_WRITE_BYTES - 1;
60 }
61
62 /* Do the last write, 2 to 5 bytes. */
63 err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
64 cpu_to_le16(buf[offset]), size - offset - 1,
65 &buf[offset + 1], NULL);
66 if (err)
67 goto err_out;
68
69 return size;
70
71 err_out:
72 dev_err(ice_pf_to_dev(pf), "GNSS failed to write, offset=%u, size=%u, err=%d\n",
73 offset, size, err);
74
75 return err;
76 }
77
78 /**
79 * ice_gnss_read - Read data from internal GNSS module
80 * @work: GNSS read work structure
81 *
82 * Read the data from internal GNSS receiver, write it to gnss_dev.
83 */
ice_gnss_read(struct kthread_work * work)84 static void ice_gnss_read(struct kthread_work *work)
85 {
86 struct gnss_serial *gnss = container_of(work, struct gnss_serial,
87 read_work.work);
88 unsigned long delay = ICE_GNSS_POLL_DATA_DELAY_TIME;
89 unsigned int i, bytes_read, data_len, count;
90 struct ice_aqc_link_topo_addr link_topo;
91 struct ice_pf *pf;
92 struct ice_hw *hw;
93 __be16 data_len_b;
94 char *buf = NULL;
95 u8 i2c_params;
96 int err = 0;
97
98 pf = gnss->back;
99 if (!pf || !test_bit(ICE_FLAG_GNSS, pf->flags))
100 return;
101
102 hw = &pf->hw;
103
104 memset(&link_topo, 0, sizeof(struct ice_aqc_link_topo_addr));
105 link_topo.topo_params.index = ICE_E810T_GNSS_I2C_BUS;
106 link_topo.topo_params.node_type_ctx |=
107 FIELD_PREP(ICE_AQC_LINK_TOPO_NODE_CTX_M,
108 ICE_AQC_LINK_TOPO_NODE_CTX_OVERRIDE);
109
110 i2c_params = ICE_GNSS_UBX_DATA_LEN_WIDTH |
111 ICE_AQC_I2C_USE_REPEATED_START;
112
113 err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
114 cpu_to_le16(ICE_GNSS_UBX_DATA_LEN_H),
115 i2c_params, (u8 *)&data_len_b, NULL);
116 if (err)
117 goto requeue;
118
119 data_len = be16_to_cpu(data_len_b);
120 if (data_len == 0 || data_len == U16_MAX)
121 goto requeue;
122
123 /* The u-blox has data_len bytes for us to read */
124
125 data_len = min_t(typeof(data_len), data_len, PAGE_SIZE);
126
127 buf = (char *)get_zeroed_page(GFP_KERNEL);
128 if (!buf) {
129 err = -ENOMEM;
130 goto requeue;
131 }
132
133 /* Read received data */
134 for (i = 0; i < data_len; i += bytes_read) {
135 unsigned int bytes_left = data_len - i;
136
137 bytes_read = min_t(typeof(bytes_left), bytes_left,
138 ICE_MAX_I2C_DATA_SIZE);
139
140 err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
141 cpu_to_le16(ICE_GNSS_UBX_EMPTY_DATA),
142 bytes_read, &buf[i], NULL);
143 if (err)
144 goto free_buf;
145 }
146
147 count = gnss_insert_raw(pf->gnss_dev, buf, i);
148 if (count != i)
149 dev_warn(ice_pf_to_dev(pf),
150 "gnss_insert_raw ret=%d size=%d\n",
151 count, i);
152 delay = ICE_GNSS_TIMER_DELAY_TIME;
153 free_buf:
154 free_page((unsigned long)buf);
155 requeue:
156 kthread_queue_delayed_work(gnss->kworker, &gnss->read_work, delay);
157 if (err)
158 dev_dbg(ice_pf_to_dev(pf), "GNSS failed to read err=%d\n", err);
159 }
160
161 /**
162 * ice_gnss_struct_init - Initialize GNSS receiver
163 * @pf: Board private structure
164 *
165 * Initialize GNSS structures and workers.
166 *
167 * Return:
168 * * pointer to initialized gnss_serial struct - success
169 * * NULL - error
170 */
ice_gnss_struct_init(struct ice_pf * pf)171 static struct gnss_serial *ice_gnss_struct_init(struct ice_pf *pf)
172 {
173 struct device *dev = ice_pf_to_dev(pf);
174 struct kthread_worker *kworker;
175 struct gnss_serial *gnss;
176
177 gnss = kzalloc(sizeof(*gnss), GFP_KERNEL);
178 if (!gnss)
179 return NULL;
180
181 gnss->back = pf;
182 pf->gnss_serial = gnss;
183
184 kthread_init_delayed_work(&gnss->read_work, ice_gnss_read);
185 kworker = kthread_create_worker(0, "ice-gnss-%s", dev_name(dev));
186 if (IS_ERR(kworker)) {
187 kfree(gnss);
188 return NULL;
189 }
190
191 gnss->kworker = kworker;
192
193 return gnss;
194 }
195
196 /**
197 * ice_gnss_open - Open GNSS device
198 * @gdev: pointer to the gnss device struct
199 *
200 * Open GNSS device and start filling the read buffer for consumer.
201 *
202 * Return:
203 * * 0 - success
204 * * negative - error code
205 */
ice_gnss_open(struct gnss_device * gdev)206 static int ice_gnss_open(struct gnss_device *gdev)
207 {
208 struct ice_pf *pf = gnss_get_drvdata(gdev);
209 struct gnss_serial *gnss;
210
211 if (!pf)
212 return -EFAULT;
213
214 if (!test_bit(ICE_FLAG_GNSS, pf->flags))
215 return -EFAULT;
216
217 gnss = pf->gnss_serial;
218 if (!gnss)
219 return -ENODEV;
220
221 kthread_queue_delayed_work(gnss->kworker, &gnss->read_work, 0);
222
223 return 0;
224 }
225
226 /**
227 * ice_gnss_close - Close GNSS device
228 * @gdev: pointer to the gnss device struct
229 *
230 * Close GNSS device, cancel worker, stop filling the read buffer.
231 */
ice_gnss_close(struct gnss_device * gdev)232 static void ice_gnss_close(struct gnss_device *gdev)
233 {
234 struct ice_pf *pf = gnss_get_drvdata(gdev);
235 struct gnss_serial *gnss;
236
237 if (!pf)
238 return;
239
240 gnss = pf->gnss_serial;
241 if (!gnss)
242 return;
243
244 kthread_cancel_delayed_work_sync(&gnss->read_work);
245 }
246
247 /**
248 * ice_gnss_write - Write to GNSS device
249 * @gdev: pointer to the gnss device struct
250 * @buf: pointer to the user data
251 * @count: size of the buffer to be sent to the GNSS device
252 *
253 * Return:
254 * * number of written bytes - success
255 * * negative - error code
256 */
257 static int
ice_gnss_write(struct gnss_device * gdev,const unsigned char * buf,size_t count)258 ice_gnss_write(struct gnss_device *gdev, const unsigned char *buf,
259 size_t count)
260 {
261 struct ice_pf *pf = gnss_get_drvdata(gdev);
262 struct gnss_serial *gnss;
263
264 /* We cannot write a single byte using our I2C implementation. */
265 if (count <= 1 || count > ICE_GNSS_TTY_WRITE_BUF)
266 return -EINVAL;
267
268 if (!pf)
269 return -EFAULT;
270
271 if (!test_bit(ICE_FLAG_GNSS, pf->flags))
272 return -EFAULT;
273
274 gnss = pf->gnss_serial;
275 if (!gnss)
276 return -ENODEV;
277
278 return ice_gnss_do_write(pf, buf, count);
279 }
280
281 static const struct gnss_operations ice_gnss_ops = {
282 .open = ice_gnss_open,
283 .close = ice_gnss_close,
284 .write_raw = ice_gnss_write,
285 };
286
287 /**
288 * ice_gnss_register - Register GNSS receiver
289 * @pf: Board private structure
290 *
291 * Allocate and register GNSS receiver in the Linux GNSS subsystem.
292 *
293 * Return:
294 * * 0 - success
295 * * negative - error code
296 */
ice_gnss_register(struct ice_pf * pf)297 static int ice_gnss_register(struct ice_pf *pf)
298 {
299 struct gnss_device *gdev;
300 int ret;
301
302 gdev = gnss_allocate_device(ice_pf_to_dev(pf));
303 if (!gdev) {
304 dev_err(ice_pf_to_dev(pf),
305 "gnss_allocate_device returns NULL\n");
306 return -ENOMEM;
307 }
308
309 gdev->ops = &ice_gnss_ops;
310 gdev->type = GNSS_TYPE_UBX;
311 gnss_set_drvdata(gdev, pf);
312 ret = gnss_register_device(gdev);
313 if (ret) {
314 dev_err(ice_pf_to_dev(pf), "gnss_register_device err=%d\n",
315 ret);
316 gnss_put_device(gdev);
317 } else {
318 pf->gnss_dev = gdev;
319 }
320
321 return ret;
322 }
323
324 /**
325 * ice_gnss_deregister - Deregister GNSS receiver
326 * @pf: Board private structure
327 *
328 * Deregister GNSS receiver from the Linux GNSS subsystem,
329 * release its resources.
330 */
ice_gnss_deregister(struct ice_pf * pf)331 static void ice_gnss_deregister(struct ice_pf *pf)
332 {
333 if (pf->gnss_dev) {
334 gnss_deregister_device(pf->gnss_dev);
335 gnss_put_device(pf->gnss_dev);
336 pf->gnss_dev = NULL;
337 }
338 }
339
340 /**
341 * ice_gnss_init - Initialize GNSS support
342 * @pf: Board private structure
343 */
ice_gnss_init(struct ice_pf * pf)344 void ice_gnss_init(struct ice_pf *pf)
345 {
346 int ret;
347
348 pf->gnss_serial = ice_gnss_struct_init(pf);
349 if (!pf->gnss_serial)
350 return;
351
352 ret = ice_gnss_register(pf);
353 if (!ret) {
354 set_bit(ICE_FLAG_GNSS, pf->flags);
355 dev_info(ice_pf_to_dev(pf), "GNSS init successful\n");
356 } else {
357 ice_gnss_exit(pf);
358 dev_err(ice_pf_to_dev(pf), "GNSS init failure\n");
359 }
360 }
361
362 /**
363 * ice_gnss_exit - Disable GNSS TTY support
364 * @pf: Board private structure
365 */
ice_gnss_exit(struct ice_pf * pf)366 void ice_gnss_exit(struct ice_pf *pf)
367 {
368 ice_gnss_deregister(pf);
369 clear_bit(ICE_FLAG_GNSS, pf->flags);
370
371 if (pf->gnss_serial) {
372 struct gnss_serial *gnss = pf->gnss_serial;
373
374 kthread_cancel_delayed_work_sync(&gnss->read_work);
375 kthread_destroy_worker(gnss->kworker);
376 gnss->kworker = NULL;
377
378 kfree(gnss);
379 pf->gnss_serial = NULL;
380 }
381 }
382
383 /**
384 * ice_gnss_is_gps_present - Check if GPS HW is present
385 * @hw: pointer to HW struct
386 */
ice_gnss_is_gps_present(struct ice_hw * hw)387 bool ice_gnss_is_gps_present(struct ice_hw *hw)
388 {
389 if (!hw->func_caps.ts_func_info.src_tmr_owned)
390 return false;
391
392 #if IS_ENABLED(CONFIG_PTP_1588_CLOCK)
393 if (ice_is_e810t(hw)) {
394 int err;
395 u8 data;
396
397 err = ice_read_pca9575_reg_e810t(hw, ICE_PCA9575_P0_IN, &data);
398 if (err || !!(data & ICE_E810T_P0_GNSS_PRSNT_N))
399 return false;
400 } else {
401 return false;
402 }
403 #else
404 if (!ice_is_e810t(hw))
405 return false;
406 #endif /* IS_ENABLED(CONFIG_PTP_1588_CLOCK) */
407
408 return true;
409 }
410