xref: /linux/drivers/net/wireless/zydas/zd1211rw/zd_rf_uw2453.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /* ZD1211 USB-WLAN driver for Linux
2  *
3  * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
4  * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 
23 #include "zd_rf.h"
24 #include "zd_usb.h"
25 #include "zd_chip.h"
26 
27 /* This RF programming code is based upon the code found in v2.16.0.0 of the
28  * ZyDAS vendor driver. Unlike other RF's, Ubec publish full technical specs
29  * for this RF on their website, so we're able to understand more than
30  * usual as to what is going on. Thumbs up for Ubec for doing that. */
31 
32 /* The 3-wire serial interface provides access to 8 write-only registers.
33  * The data format is a 4 bit register address followed by a 20 bit value. */
34 #define UW2453_REGWRITE(reg, val) ((((reg) & 0xf) << 20) | ((val) & 0xfffff))
35 
36 /* For channel tuning, we have to configure registers 1 (synthesizer), 2 (synth
37  * fractional divide ratio) and 3 (VCO config).
38  *
39  * We configure the RF to produce an interrupt when the PLL is locked onto
40  * the configured frequency. During initialization, we run through a variety
41  * of different VCO configurations on channel 1 until we detect a PLL lock.
42  * When this happens, we remember which VCO configuration produced the lock
43  * and use it later. Actually, we use the configuration *after* the one that
44  * produced the lock, which seems odd, but it works.
45  *
46  * If we do not see a PLL lock on any standard VCO config, we fall back on an
47  * autocal configuration, which has a fixed (as opposed to per-channel) VCO
48  * config and different synth values from the standard set (divide ratio
49  * is still shared with the standard set). */
50 
51 /* The per-channel synth values for all standard VCO configurations. These get
52  * written to register 1. */
53 static const u8 uw2453_std_synth[] = {
54 	RF_CHANNEL( 1) = 0x47,
55 	RF_CHANNEL( 2) = 0x47,
56 	RF_CHANNEL( 3) = 0x67,
57 	RF_CHANNEL( 4) = 0x67,
58 	RF_CHANNEL( 5) = 0x67,
59 	RF_CHANNEL( 6) = 0x67,
60 	RF_CHANNEL( 7) = 0x57,
61 	RF_CHANNEL( 8) = 0x57,
62 	RF_CHANNEL( 9) = 0x57,
63 	RF_CHANNEL(10) = 0x57,
64 	RF_CHANNEL(11) = 0x77,
65 	RF_CHANNEL(12) = 0x77,
66 	RF_CHANNEL(13) = 0x77,
67 	RF_CHANNEL(14) = 0x4f,
68 };
69 
70 /* This table stores the synthesizer fractional divide ratio for *all* VCO
71  * configurations (both standard and autocal). These get written to register 2.
72  */
73 static const u16 uw2453_synth_divide[] = {
74 	RF_CHANNEL( 1) = 0x999,
75 	RF_CHANNEL( 2) = 0x99b,
76 	RF_CHANNEL( 3) = 0x998,
77 	RF_CHANNEL( 4) = 0x99a,
78 	RF_CHANNEL( 5) = 0x999,
79 	RF_CHANNEL( 6) = 0x99b,
80 	RF_CHANNEL( 7) = 0x998,
81 	RF_CHANNEL( 8) = 0x99a,
82 	RF_CHANNEL( 9) = 0x999,
83 	RF_CHANNEL(10) = 0x99b,
84 	RF_CHANNEL(11) = 0x998,
85 	RF_CHANNEL(12) = 0x99a,
86 	RF_CHANNEL(13) = 0x999,
87 	RF_CHANNEL(14) = 0xccc,
88 };
89 
90 /* Here is the data for all the standard VCO configurations. We shrink our
91  * table a little by observing that both channels in a consecutive pair share
92  * the same value. We also observe that the high 4 bits ([0:3] in the specs)
93  * are all 'Reserved' and are always set to 0x4 - we chop them off in the data
94  * below. */
95 #define CHAN_TO_PAIRIDX(a) ((a - 1) / 2)
96 #define RF_CHANPAIR(a,b) [CHAN_TO_PAIRIDX(a)]
97 static const u16 uw2453_std_vco_cfg[][7] = {
98 	{ /* table 1 */
99 		RF_CHANPAIR( 1,  2) = 0x664d,
100 		RF_CHANPAIR( 3,  4) = 0x604d,
101 		RF_CHANPAIR( 5,  6) = 0x6675,
102 		RF_CHANPAIR( 7,  8) = 0x6475,
103 		RF_CHANPAIR( 9, 10) = 0x6655,
104 		RF_CHANPAIR(11, 12) = 0x6455,
105 		RF_CHANPAIR(13, 14) = 0x6665,
106 	},
107 	{ /* table 2 */
108 		RF_CHANPAIR( 1,  2) = 0x666d,
109 		RF_CHANPAIR( 3,  4) = 0x606d,
110 		RF_CHANPAIR( 5,  6) = 0x664d,
111 		RF_CHANPAIR( 7,  8) = 0x644d,
112 		RF_CHANPAIR( 9, 10) = 0x6675,
113 		RF_CHANPAIR(11, 12) = 0x6475,
114 		RF_CHANPAIR(13, 14) = 0x6655,
115 	},
116 	{ /* table 3 */
117 		RF_CHANPAIR( 1,  2) = 0x665d,
118 		RF_CHANPAIR( 3,  4) = 0x605d,
119 		RF_CHANPAIR( 5,  6) = 0x666d,
120 		RF_CHANPAIR( 7,  8) = 0x646d,
121 		RF_CHANPAIR( 9, 10) = 0x664d,
122 		RF_CHANPAIR(11, 12) = 0x644d,
123 		RF_CHANPAIR(13, 14) = 0x6675,
124 	},
125 	{ /* table 4 */
126 		RF_CHANPAIR( 1,  2) = 0x667d,
127 		RF_CHANPAIR( 3,  4) = 0x607d,
128 		RF_CHANPAIR( 5,  6) = 0x665d,
129 		RF_CHANPAIR( 7,  8) = 0x645d,
130 		RF_CHANPAIR( 9, 10) = 0x666d,
131 		RF_CHANPAIR(11, 12) = 0x646d,
132 		RF_CHANPAIR(13, 14) = 0x664d,
133 	},
134 	{ /* table 5 */
135 		RF_CHANPAIR( 1,  2) = 0x6643,
136 		RF_CHANPAIR( 3,  4) = 0x6043,
137 		RF_CHANPAIR( 5,  6) = 0x667d,
138 		RF_CHANPAIR( 7,  8) = 0x647d,
139 		RF_CHANPAIR( 9, 10) = 0x665d,
140 		RF_CHANPAIR(11, 12) = 0x645d,
141 		RF_CHANPAIR(13, 14) = 0x666d,
142 	},
143 	{ /* table 6 */
144 		RF_CHANPAIR( 1,  2) = 0x6663,
145 		RF_CHANPAIR( 3,  4) = 0x6063,
146 		RF_CHANPAIR( 5,  6) = 0x6643,
147 		RF_CHANPAIR( 7,  8) = 0x6443,
148 		RF_CHANPAIR( 9, 10) = 0x667d,
149 		RF_CHANPAIR(11, 12) = 0x647d,
150 		RF_CHANPAIR(13, 14) = 0x665d,
151 	},
152 	{ /* table 7 */
153 		RF_CHANPAIR( 1,  2) = 0x6653,
154 		RF_CHANPAIR( 3,  4) = 0x6053,
155 		RF_CHANPAIR( 5,  6) = 0x6663,
156 		RF_CHANPAIR( 7,  8) = 0x6463,
157 		RF_CHANPAIR( 9, 10) = 0x6643,
158 		RF_CHANPAIR(11, 12) = 0x6443,
159 		RF_CHANPAIR(13, 14) = 0x667d,
160 	},
161 	{ /* table 8 */
162 		RF_CHANPAIR( 1,  2) = 0x6673,
163 		RF_CHANPAIR( 3,  4) = 0x6073,
164 		RF_CHANPAIR( 5,  6) = 0x6653,
165 		RF_CHANPAIR( 7,  8) = 0x6453,
166 		RF_CHANPAIR( 9, 10) = 0x6663,
167 		RF_CHANPAIR(11, 12) = 0x6463,
168 		RF_CHANPAIR(13, 14) = 0x6643,
169 	},
170 	{ /* table 9 */
171 		RF_CHANPAIR( 1,  2) = 0x664b,
172 		RF_CHANPAIR( 3,  4) = 0x604b,
173 		RF_CHANPAIR( 5,  6) = 0x6673,
174 		RF_CHANPAIR( 7,  8) = 0x6473,
175 		RF_CHANPAIR( 9, 10) = 0x6653,
176 		RF_CHANPAIR(11, 12) = 0x6453,
177 		RF_CHANPAIR(13, 14) = 0x6663,
178 	},
179 	{ /* table 10 */
180 		RF_CHANPAIR( 1,  2) = 0x666b,
181 		RF_CHANPAIR( 3,  4) = 0x606b,
182 		RF_CHANPAIR( 5,  6) = 0x664b,
183 		RF_CHANPAIR( 7,  8) = 0x644b,
184 		RF_CHANPAIR( 9, 10) = 0x6673,
185 		RF_CHANPAIR(11, 12) = 0x6473,
186 		RF_CHANPAIR(13, 14) = 0x6653,
187 	},
188 	{ /* table 11 */
189 		RF_CHANPAIR( 1,  2) = 0x665b,
190 		RF_CHANPAIR( 3,  4) = 0x605b,
191 		RF_CHANPAIR( 5,  6) = 0x666b,
192 		RF_CHANPAIR( 7,  8) = 0x646b,
193 		RF_CHANPAIR( 9, 10) = 0x664b,
194 		RF_CHANPAIR(11, 12) = 0x644b,
195 		RF_CHANPAIR(13, 14) = 0x6673,
196 	},
197 
198 };
199 
200 /* The per-channel synth values for autocal. These get written to register 1. */
201 static const u16 uw2453_autocal_synth[] = {
202 	RF_CHANNEL( 1) = 0x6847,
203 	RF_CHANNEL( 2) = 0x6847,
204 	RF_CHANNEL( 3) = 0x6867,
205 	RF_CHANNEL( 4) = 0x6867,
206 	RF_CHANNEL( 5) = 0x6867,
207 	RF_CHANNEL( 6) = 0x6867,
208 	RF_CHANNEL( 7) = 0x6857,
209 	RF_CHANNEL( 8) = 0x6857,
210 	RF_CHANNEL( 9) = 0x6857,
211 	RF_CHANNEL(10) = 0x6857,
212 	RF_CHANNEL(11) = 0x6877,
213 	RF_CHANNEL(12) = 0x6877,
214 	RF_CHANNEL(13) = 0x6877,
215 	RF_CHANNEL(14) = 0x684f,
216 };
217 
218 /* The VCO configuration for autocal (all channels) */
219 static const u16 UW2453_AUTOCAL_VCO_CFG = 0x6662;
220 
221 /* TX gain settings. The array index corresponds to the TX power integration
222  * values found in the EEPROM. The values get written to register 7. */
223 static u32 uw2453_txgain[] = {
224 	[0x00] = 0x0e313,
225 	[0x01] = 0x0fb13,
226 	[0x02] = 0x0e093,
227 	[0x03] = 0x0f893,
228 	[0x04] = 0x0ea93,
229 	[0x05] = 0x1f093,
230 	[0x06] = 0x1f493,
231 	[0x07] = 0x1f693,
232 	[0x08] = 0x1f393,
233 	[0x09] = 0x1f35b,
234 	[0x0a] = 0x1e6db,
235 	[0x0b] = 0x1ff3f,
236 	[0x0c] = 0x1ffff,
237 	[0x0d] = 0x361d7,
238 	[0x0e] = 0x37fbf,
239 	[0x0f] = 0x3ff8b,
240 	[0x10] = 0x3ff33,
241 	[0x11] = 0x3fb3f,
242 	[0x12] = 0x3ffff,
243 };
244 
245 /* RF-specific structure */
246 struct uw2453_priv {
247 	/* index into synth/VCO config tables where PLL lock was found
248 	 * -1 means autocal */
249 	int config;
250 };
251 
252 #define UW2453_PRIV(rf) ((struct uw2453_priv *) (rf)->priv)
253 
254 static int uw2453_synth_set_channel(struct zd_chip *chip, int channel,
255 	bool autocal)
256 {
257 	int r;
258 	int idx = channel - 1;
259 	u32 val;
260 
261 	if (autocal)
262 		val = UW2453_REGWRITE(1, uw2453_autocal_synth[idx]);
263 	else
264 		val = UW2453_REGWRITE(1, uw2453_std_synth[idx]);
265 
266 	r = zd_rfwrite_locked(chip, val, RF_RV_BITS);
267 	if (r)
268 		return r;
269 
270 	return zd_rfwrite_locked(chip,
271 		UW2453_REGWRITE(2, uw2453_synth_divide[idx]), RF_RV_BITS);
272 }
273 
274 static int uw2453_write_vco_cfg(struct zd_chip *chip, u16 value)
275 {
276 	/* vendor driver always sets these upper bits even though the specs say
277 	 * they are reserved */
278 	u32 val = 0x40000 | value;
279 	return zd_rfwrite_locked(chip, UW2453_REGWRITE(3, val), RF_RV_BITS);
280 }
281 
282 static int uw2453_init_mode(struct zd_chip *chip)
283 {
284 	static const u32 rv[] = {
285 		UW2453_REGWRITE(0, 0x25f98), /* enter IDLE mode */
286 		UW2453_REGWRITE(0, 0x25f9a), /* enter CAL_VCO mode */
287 		UW2453_REGWRITE(0, 0x25f94), /* enter RX/TX mode */
288 		UW2453_REGWRITE(0, 0x27fd4), /* power down RSSI circuit */
289 	};
290 
291 	return zd_rfwritev_locked(chip, rv, ARRAY_SIZE(rv), RF_RV_BITS);
292 }
293 
294 static int uw2453_set_tx_gain_level(struct zd_chip *chip, int channel)
295 {
296 	u8 int_value = chip->pwr_int_values[channel - 1];
297 
298 	if (int_value >= ARRAY_SIZE(uw2453_txgain)) {
299 		dev_dbg_f(zd_chip_dev(chip), "can't configure TX gain for "
300 			  "int value %x on channel %d\n", int_value, channel);
301 		return 0;
302 	}
303 
304 	return zd_rfwrite_locked(chip,
305 		UW2453_REGWRITE(7, uw2453_txgain[int_value]), RF_RV_BITS);
306 }
307 
308 static int uw2453_init_hw(struct zd_rf *rf)
309 {
310 	int i, r;
311 	int found_config = -1;
312 	u16 intr_status;
313 	struct zd_chip *chip = zd_rf_to_chip(rf);
314 
315 	static const struct zd_ioreq16 ioreqs[] = {
316 		{ ZD_CR10,  0x89 }, { ZD_CR15,  0x20 },
317 		{ ZD_CR17,  0x28 }, /* 6112 no change */
318 		{ ZD_CR23,  0x38 }, { ZD_CR24,  0x20 }, { ZD_CR26,  0x93 },
319 		{ ZD_CR27,  0x15 }, { ZD_CR28,  0x3e }, { ZD_CR29,  0x00 },
320 		{ ZD_CR33,  0x28 }, { ZD_CR34,  0x30 },
321 		{ ZD_CR35,  0x43 }, /* 6112 3e->43 */
322 		{ ZD_CR41,  0x24 }, { ZD_CR44,  0x32 },
323 		{ ZD_CR46,  0x92 }, /* 6112 96->92 */
324 		{ ZD_CR47,  0x1e },
325 		{ ZD_CR48,  0x04 }, /* 5602 Roger */
326 		{ ZD_CR49,  0xfa }, { ZD_CR79,  0x58 }, { ZD_CR80,  0x30 },
327 		{ ZD_CR81,  0x30 }, { ZD_CR87,  0x0a }, { ZD_CR89,  0x04 },
328 		{ ZD_CR91,  0x00 }, { ZD_CR92,  0x0a }, { ZD_CR98,  0x8d },
329 		{ ZD_CR99,  0x28 }, { ZD_CR100, 0x02 },
330 		{ ZD_CR101, 0x09 }, /* 6112 13->1f 6220 1f->13 6407 13->9 */
331 		{ ZD_CR102, 0x27 },
332 		{ ZD_CR106, 0x1c }, /* 5d07 5112 1f->1c 6220 1c->1f
333 				     * 6221 1f->1c
334 				     */
335 		{ ZD_CR107, 0x1c }, /* 6220 1c->1a 5221 1a->1c */
336 		{ ZD_CR109, 0x13 },
337 		{ ZD_CR110, 0x1f }, /* 6112 13->1f 6221 1f->13 6407 13->0x09 */
338 		{ ZD_CR111, 0x13 }, { ZD_CR112, 0x1f }, { ZD_CR113, 0x27 },
339 		{ ZD_CR114, 0x23 }, /* 6221 27->23 */
340 		{ ZD_CR115, 0x24 }, /* 6112 24->1c 6220 1c->24 */
341 		{ ZD_CR116, 0x24 }, /* 6220 1c->24 */
342 		{ ZD_CR117, 0xfa }, /* 6112 fa->f8 6220 f8->f4 6220 f4->fa */
343 		{ ZD_CR118, 0xf0 }, /* 5d07 6112 f0->f2 6220 f2->f0 */
344 		{ ZD_CR119, 0x1a }, /* 6112 1a->10 6220 10->14 6220 14->1a */
345 		{ ZD_CR120, 0x4f },
346 		{ ZD_CR121, 0x1f }, /* 6220 4f->1f */
347 		{ ZD_CR122, 0xf0 }, { ZD_CR123, 0x57 }, { ZD_CR125, 0xad },
348 		{ ZD_CR126, 0x6c }, { ZD_CR127, 0x03 },
349 		{ ZD_CR128, 0x14 }, /* 6302 12->11 */
350 		{ ZD_CR129, 0x12 }, /* 6301 10->0f */
351 		{ ZD_CR130, 0x10 }, { ZD_CR137, 0x50 }, { ZD_CR138, 0xa8 },
352 		{ ZD_CR144, 0xac }, { ZD_CR146, 0x20 }, { ZD_CR252, 0xff },
353 		{ ZD_CR253, 0xff },
354 	};
355 
356 	static const u32 rv[] = {
357 		UW2453_REGWRITE(4, 0x2b),    /* configure receiver gain */
358 		UW2453_REGWRITE(5, 0x19e4f), /* configure transmitter gain */
359 		UW2453_REGWRITE(6, 0xf81ad), /* enable RX/TX filter tuning */
360 		UW2453_REGWRITE(7, 0x3fffe), /* disable TX gain in test mode */
361 
362 		/* enter CAL_FIL mode, TX gain set by registers, RX gain set by pins,
363 		 * RSSI circuit powered down, reduced RSSI range */
364 		UW2453_REGWRITE(0, 0x25f9c), /* 5d01 cal_fil */
365 
366 		/* synthesizer configuration for channel 1 */
367 		UW2453_REGWRITE(1, 0x47),
368 		UW2453_REGWRITE(2, 0x999),
369 
370 		/* disable manual VCO band selection */
371 		UW2453_REGWRITE(3, 0x7602),
372 
373 		/* enable manual VCO band selection, configure current level */
374 		UW2453_REGWRITE(3, 0x46063),
375 	};
376 
377 	r = zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
378 	if (r)
379 		return r;
380 
381 	r = zd_rfwritev_locked(chip, rv, ARRAY_SIZE(rv), RF_RV_BITS);
382 	if (r)
383 		return r;
384 
385 	r = uw2453_init_mode(chip);
386 	if (r)
387 		return r;
388 
389 	/* Try all standard VCO configuration settings on channel 1 */
390 	for (i = 0; i < ARRAY_SIZE(uw2453_std_vco_cfg) - 1; i++) {
391 		/* Configure synthesizer for channel 1 */
392 		r = uw2453_synth_set_channel(chip, 1, false);
393 		if (r)
394 			return r;
395 
396 		/* Write VCO config */
397 		r = uw2453_write_vco_cfg(chip, uw2453_std_vco_cfg[i][0]);
398 		if (r)
399 			return r;
400 
401 		/* ack interrupt event */
402 		r = zd_iowrite16_locked(chip, 0x0f, UW2453_INTR_REG);
403 		if (r)
404 			return r;
405 
406 		/* check interrupt status */
407 		r = zd_ioread16_locked(chip, &intr_status, UW2453_INTR_REG);
408 		if (r)
409 			return r;
410 
411 		if (!(intr_status & 0xf)) {
412 			dev_dbg_f(zd_chip_dev(chip),
413 				"PLL locked on configuration %d\n", i);
414 			found_config = i;
415 			break;
416 		}
417 	}
418 
419 	if (found_config == -1) {
420 		/* autocal */
421 		dev_dbg_f(zd_chip_dev(chip),
422 			"PLL did not lock, using autocal\n");
423 
424 		r = uw2453_synth_set_channel(chip, 1, true);
425 		if (r)
426 			return r;
427 
428 		r = uw2453_write_vco_cfg(chip, UW2453_AUTOCAL_VCO_CFG);
429 		if (r)
430 			return r;
431 	}
432 
433 	/* To match the vendor driver behaviour, we use the configuration after
434 	 * the one that produced a lock. */
435 	UW2453_PRIV(rf)->config = found_config + 1;
436 
437 	return zd_iowrite16_locked(chip, 0x06, ZD_CR203);
438 }
439 
440 static int uw2453_set_channel(struct zd_rf *rf, u8 channel)
441 {
442 	int r;
443 	u16 vco_cfg;
444 	int config = UW2453_PRIV(rf)->config;
445 	bool autocal = (config == -1);
446 	struct zd_chip *chip = zd_rf_to_chip(rf);
447 
448 	static const struct zd_ioreq16 ioreqs[] = {
449 		{ ZD_CR80,  0x30 }, { ZD_CR81,  0x30 }, { ZD_CR79,  0x58 },
450 		{ ZD_CR12,  0xf0 }, { ZD_CR77,  0x1b }, { ZD_CR78,  0x58 },
451 	};
452 
453 	r = uw2453_synth_set_channel(chip, channel, autocal);
454 	if (r)
455 		return r;
456 
457 	if (autocal)
458 		vco_cfg = UW2453_AUTOCAL_VCO_CFG;
459 	else
460 		vco_cfg = uw2453_std_vco_cfg[config][CHAN_TO_PAIRIDX(channel)];
461 
462 	r = uw2453_write_vco_cfg(chip, vco_cfg);
463 	if (r)
464 		return r;
465 
466 	r = uw2453_init_mode(chip);
467 	if (r)
468 		return r;
469 
470 	r = zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
471 	if (r)
472 		return r;
473 
474 	r = uw2453_set_tx_gain_level(chip, channel);
475 	if (r)
476 		return r;
477 
478 	return zd_iowrite16_locked(chip, 0x06, ZD_CR203);
479 }
480 
481 static int uw2453_switch_radio_on(struct zd_rf *rf)
482 {
483 	int r;
484 	struct zd_chip *chip = zd_rf_to_chip(rf);
485 	struct zd_ioreq16 ioreqs[] = {
486 		{ ZD_CR11,  0x00 }, { ZD_CR251, 0x3f },
487 	};
488 
489 	/* enter RXTX mode */
490 	r = zd_rfwrite_locked(chip, UW2453_REGWRITE(0, 0x25f94), RF_RV_BITS);
491 	if (r)
492 		return r;
493 
494 	if (zd_chip_is_zd1211b(chip))
495 		ioreqs[1].value = 0x7f;
496 
497 	return zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
498 }
499 
500 static int uw2453_switch_radio_off(struct zd_rf *rf)
501 {
502 	int r;
503 	struct zd_chip *chip = zd_rf_to_chip(rf);
504 	static const struct zd_ioreq16 ioreqs[] = {
505 		{ ZD_CR11,  0x04 }, { ZD_CR251, 0x2f },
506 	};
507 
508 	/* enter IDLE mode */
509 	/* FIXME: shouldn't we go to SLEEP? sent email to zydas */
510 	r = zd_rfwrite_locked(chip, UW2453_REGWRITE(0, 0x25f90), RF_RV_BITS);
511 	if (r)
512 		return r;
513 
514 	return zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
515 }
516 
517 static void uw2453_clear(struct zd_rf *rf)
518 {
519 	kfree(rf->priv);
520 }
521 
522 int zd_rf_init_uw2453(struct zd_rf *rf)
523 {
524 	rf->init_hw = uw2453_init_hw;
525 	rf->set_channel = uw2453_set_channel;
526 	rf->switch_radio_on = uw2453_switch_radio_on;
527 	rf->switch_radio_off = uw2453_switch_radio_off;
528 	rf->patch_6m_band_edge = zd_rf_generic_patch_6m;
529 	rf->clear = uw2453_clear;
530 	/* we have our own TX integration code */
531 	rf->update_channel_int = 0;
532 
533 	rf->priv = kmalloc(sizeof(struct uw2453_priv), GFP_KERNEL);
534 	if (rf->priv == NULL)
535 		return -ENOMEM;
536 
537 	return 0;
538 }
539 
540