cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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zd_rf_uw2453.c (15104B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/* ZD1211 USB-WLAN driver for Linux
      3 *
      4 * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
      5 * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
      6 */
      7
      8#include <linux/kernel.h>
      9#include <linux/slab.h>
     10
     11#include "zd_rf.h"
     12#include "zd_usb.h"
     13#include "zd_chip.h"
     14
     15/* This RF programming code is based upon the code found in v2.16.0.0 of the
     16 * ZyDAS vendor driver. Unlike other RF's, Ubec publish full technical specs
     17 * for this RF on their website, so we're able to understand more than
     18 * usual as to what is going on. Thumbs up for Ubec for doing that. */
     19
     20/* The 3-wire serial interface provides access to 8 write-only registers.
     21 * The data format is a 4 bit register address followed by a 20 bit value. */
     22#define UW2453_REGWRITE(reg, val) ((((reg) & 0xf) << 20) | ((val) & 0xfffff))
     23
     24/* For channel tuning, we have to configure registers 1 (synthesizer), 2 (synth
     25 * fractional divide ratio) and 3 (VCO config).
     26 *
     27 * We configure the RF to produce an interrupt when the PLL is locked onto
     28 * the configured frequency. During initialization, we run through a variety
     29 * of different VCO configurations on channel 1 until we detect a PLL lock.
     30 * When this happens, we remember which VCO configuration produced the lock
     31 * and use it later. Actually, we use the configuration *after* the one that
     32 * produced the lock, which seems odd, but it works.
     33 *
     34 * If we do not see a PLL lock on any standard VCO config, we fall back on an
     35 * autocal configuration, which has a fixed (as opposed to per-channel) VCO
     36 * config and different synth values from the standard set (divide ratio
     37 * is still shared with the standard set). */
     38
     39/* The per-channel synth values for all standard VCO configurations. These get
     40 * written to register 1. */
     41static const u8 uw2453_std_synth[] = {
     42	RF_CHANNEL( 1) = 0x47,
     43	RF_CHANNEL( 2) = 0x47,
     44	RF_CHANNEL( 3) = 0x67,
     45	RF_CHANNEL( 4) = 0x67,
     46	RF_CHANNEL( 5) = 0x67,
     47	RF_CHANNEL( 6) = 0x67,
     48	RF_CHANNEL( 7) = 0x57,
     49	RF_CHANNEL( 8) = 0x57,
     50	RF_CHANNEL( 9) = 0x57,
     51	RF_CHANNEL(10) = 0x57,
     52	RF_CHANNEL(11) = 0x77,
     53	RF_CHANNEL(12) = 0x77,
     54	RF_CHANNEL(13) = 0x77,
     55	RF_CHANNEL(14) = 0x4f,
     56};
     57
     58/* This table stores the synthesizer fractional divide ratio for *all* VCO
     59 * configurations (both standard and autocal). These get written to register 2.
     60 */
     61static const u16 uw2453_synth_divide[] = {
     62	RF_CHANNEL( 1) = 0x999,
     63	RF_CHANNEL( 2) = 0x99b,
     64	RF_CHANNEL( 3) = 0x998,
     65	RF_CHANNEL( 4) = 0x99a,
     66	RF_CHANNEL( 5) = 0x999,
     67	RF_CHANNEL( 6) = 0x99b,
     68	RF_CHANNEL( 7) = 0x998,
     69	RF_CHANNEL( 8) = 0x99a,
     70	RF_CHANNEL( 9) = 0x999,
     71	RF_CHANNEL(10) = 0x99b,
     72	RF_CHANNEL(11) = 0x998,
     73	RF_CHANNEL(12) = 0x99a,
     74	RF_CHANNEL(13) = 0x999,
     75	RF_CHANNEL(14) = 0xccc,
     76};
     77
     78/* Here is the data for all the standard VCO configurations. We shrink our
     79 * table a little by observing that both channels in a consecutive pair share
     80 * the same value. We also observe that the high 4 bits ([0:3] in the specs)
     81 * are all 'Reserved' and are always set to 0x4 - we chop them off in the data
     82 * below. */
     83#define CHAN_TO_PAIRIDX(a) ((a - 1) / 2)
     84#define RF_CHANPAIR(a,b) [CHAN_TO_PAIRIDX(a)]
     85static const u16 uw2453_std_vco_cfg[][7] = {
     86	{ /* table 1 */
     87		RF_CHANPAIR( 1,  2) = 0x664d,
     88		RF_CHANPAIR( 3,  4) = 0x604d,
     89		RF_CHANPAIR( 5,  6) = 0x6675,
     90		RF_CHANPAIR( 7,  8) = 0x6475,
     91		RF_CHANPAIR( 9, 10) = 0x6655,
     92		RF_CHANPAIR(11, 12) = 0x6455,
     93		RF_CHANPAIR(13, 14) = 0x6665,
     94	},
     95	{ /* table 2 */
     96		RF_CHANPAIR( 1,  2) = 0x666d,
     97		RF_CHANPAIR( 3,  4) = 0x606d,
     98		RF_CHANPAIR( 5,  6) = 0x664d,
     99		RF_CHANPAIR( 7,  8) = 0x644d,
    100		RF_CHANPAIR( 9, 10) = 0x6675,
    101		RF_CHANPAIR(11, 12) = 0x6475,
    102		RF_CHANPAIR(13, 14) = 0x6655,
    103	},
    104	{ /* table 3 */
    105		RF_CHANPAIR( 1,  2) = 0x665d,
    106		RF_CHANPAIR( 3,  4) = 0x605d,
    107		RF_CHANPAIR( 5,  6) = 0x666d,
    108		RF_CHANPAIR( 7,  8) = 0x646d,
    109		RF_CHANPAIR( 9, 10) = 0x664d,
    110		RF_CHANPAIR(11, 12) = 0x644d,
    111		RF_CHANPAIR(13, 14) = 0x6675,
    112	},
    113	{ /* table 4 */
    114		RF_CHANPAIR( 1,  2) = 0x667d,
    115		RF_CHANPAIR( 3,  4) = 0x607d,
    116		RF_CHANPAIR( 5,  6) = 0x665d,
    117		RF_CHANPAIR( 7,  8) = 0x645d,
    118		RF_CHANPAIR( 9, 10) = 0x666d,
    119		RF_CHANPAIR(11, 12) = 0x646d,
    120		RF_CHANPAIR(13, 14) = 0x664d,
    121	},
    122	{ /* table 5 */
    123		RF_CHANPAIR( 1,  2) = 0x6643,
    124		RF_CHANPAIR( 3,  4) = 0x6043,
    125		RF_CHANPAIR( 5,  6) = 0x667d,
    126		RF_CHANPAIR( 7,  8) = 0x647d,
    127		RF_CHANPAIR( 9, 10) = 0x665d,
    128		RF_CHANPAIR(11, 12) = 0x645d,
    129		RF_CHANPAIR(13, 14) = 0x666d,
    130	},
    131	{ /* table 6 */
    132		RF_CHANPAIR( 1,  2) = 0x6663,
    133		RF_CHANPAIR( 3,  4) = 0x6063,
    134		RF_CHANPAIR( 5,  6) = 0x6643,
    135		RF_CHANPAIR( 7,  8) = 0x6443,
    136		RF_CHANPAIR( 9, 10) = 0x667d,
    137		RF_CHANPAIR(11, 12) = 0x647d,
    138		RF_CHANPAIR(13, 14) = 0x665d,
    139	},
    140	{ /* table 7 */
    141		RF_CHANPAIR( 1,  2) = 0x6653,
    142		RF_CHANPAIR( 3,  4) = 0x6053,
    143		RF_CHANPAIR( 5,  6) = 0x6663,
    144		RF_CHANPAIR( 7,  8) = 0x6463,
    145		RF_CHANPAIR( 9, 10) = 0x6643,
    146		RF_CHANPAIR(11, 12) = 0x6443,
    147		RF_CHANPAIR(13, 14) = 0x667d,
    148	},
    149	{ /* table 8 */
    150		RF_CHANPAIR( 1,  2) = 0x6673,
    151		RF_CHANPAIR( 3,  4) = 0x6073,
    152		RF_CHANPAIR( 5,  6) = 0x6653,
    153		RF_CHANPAIR( 7,  8) = 0x6453,
    154		RF_CHANPAIR( 9, 10) = 0x6663,
    155		RF_CHANPAIR(11, 12) = 0x6463,
    156		RF_CHANPAIR(13, 14) = 0x6643,
    157	},
    158	{ /* table 9 */
    159		RF_CHANPAIR( 1,  2) = 0x664b,
    160		RF_CHANPAIR( 3,  4) = 0x604b,
    161		RF_CHANPAIR( 5,  6) = 0x6673,
    162		RF_CHANPAIR( 7,  8) = 0x6473,
    163		RF_CHANPAIR( 9, 10) = 0x6653,
    164		RF_CHANPAIR(11, 12) = 0x6453,
    165		RF_CHANPAIR(13, 14) = 0x6663,
    166	},
    167	{ /* table 10 */
    168		RF_CHANPAIR( 1,  2) = 0x666b,
    169		RF_CHANPAIR( 3,  4) = 0x606b,
    170		RF_CHANPAIR( 5,  6) = 0x664b,
    171		RF_CHANPAIR( 7,  8) = 0x644b,
    172		RF_CHANPAIR( 9, 10) = 0x6673,
    173		RF_CHANPAIR(11, 12) = 0x6473,
    174		RF_CHANPAIR(13, 14) = 0x6653,
    175	},
    176	{ /* table 11 */
    177		RF_CHANPAIR( 1,  2) = 0x665b,
    178		RF_CHANPAIR( 3,  4) = 0x605b,
    179		RF_CHANPAIR( 5,  6) = 0x666b,
    180		RF_CHANPAIR( 7,  8) = 0x646b,
    181		RF_CHANPAIR( 9, 10) = 0x664b,
    182		RF_CHANPAIR(11, 12) = 0x644b,
    183		RF_CHANPAIR(13, 14) = 0x6673,
    184	},
    185
    186};
    187
    188/* The per-channel synth values for autocal. These get written to register 1. */
    189static const u16 uw2453_autocal_synth[] = {
    190	RF_CHANNEL( 1) = 0x6847,
    191	RF_CHANNEL( 2) = 0x6847,
    192	RF_CHANNEL( 3) = 0x6867,
    193	RF_CHANNEL( 4) = 0x6867,
    194	RF_CHANNEL( 5) = 0x6867,
    195	RF_CHANNEL( 6) = 0x6867,
    196	RF_CHANNEL( 7) = 0x6857,
    197	RF_CHANNEL( 8) = 0x6857,
    198	RF_CHANNEL( 9) = 0x6857,
    199	RF_CHANNEL(10) = 0x6857,
    200	RF_CHANNEL(11) = 0x6877,
    201	RF_CHANNEL(12) = 0x6877,
    202	RF_CHANNEL(13) = 0x6877,
    203	RF_CHANNEL(14) = 0x684f,
    204};
    205
    206/* The VCO configuration for autocal (all channels) */
    207static const u16 UW2453_AUTOCAL_VCO_CFG = 0x6662;
    208
    209/* TX gain settings. The array index corresponds to the TX power integration
    210 * values found in the EEPROM. The values get written to register 7. */
    211static u32 uw2453_txgain[] = {
    212	[0x00] = 0x0e313,
    213	[0x01] = 0x0fb13,
    214	[0x02] = 0x0e093,
    215	[0x03] = 0x0f893,
    216	[0x04] = 0x0ea93,
    217	[0x05] = 0x1f093,
    218	[0x06] = 0x1f493,
    219	[0x07] = 0x1f693,
    220	[0x08] = 0x1f393,
    221	[0x09] = 0x1f35b,
    222	[0x0a] = 0x1e6db,
    223	[0x0b] = 0x1ff3f,
    224	[0x0c] = 0x1ffff,
    225	[0x0d] = 0x361d7,
    226	[0x0e] = 0x37fbf,
    227	[0x0f] = 0x3ff8b,
    228	[0x10] = 0x3ff33,
    229	[0x11] = 0x3fb3f,
    230	[0x12] = 0x3ffff,
    231};
    232
    233/* RF-specific structure */
    234struct uw2453_priv {
    235	/* index into synth/VCO config tables where PLL lock was found
    236	 * -1 means autocal */
    237	int config;
    238};
    239
    240#define UW2453_PRIV(rf) ((struct uw2453_priv *) (rf)->priv)
    241
    242static int uw2453_synth_set_channel(struct zd_chip *chip, int channel,
    243	bool autocal)
    244{
    245	int r;
    246	int idx = channel - 1;
    247	u32 val;
    248
    249	if (autocal)
    250		val = UW2453_REGWRITE(1, uw2453_autocal_synth[idx]);
    251	else
    252		val = UW2453_REGWRITE(1, uw2453_std_synth[idx]);
    253
    254	r = zd_rfwrite_locked(chip, val, RF_RV_BITS);
    255	if (r)
    256		return r;
    257
    258	return zd_rfwrite_locked(chip,
    259		UW2453_REGWRITE(2, uw2453_synth_divide[idx]), RF_RV_BITS);
    260}
    261
    262static int uw2453_write_vco_cfg(struct zd_chip *chip, u16 value)
    263{
    264	/* vendor driver always sets these upper bits even though the specs say
    265	 * they are reserved */
    266	u32 val = 0x40000 | value;
    267	return zd_rfwrite_locked(chip, UW2453_REGWRITE(3, val), RF_RV_BITS);
    268}
    269
    270static int uw2453_init_mode(struct zd_chip *chip)
    271{
    272	static const u32 rv[] = {
    273		UW2453_REGWRITE(0, 0x25f98), /* enter IDLE mode */
    274		UW2453_REGWRITE(0, 0x25f9a), /* enter CAL_VCO mode */
    275		UW2453_REGWRITE(0, 0x25f94), /* enter RX/TX mode */
    276		UW2453_REGWRITE(0, 0x27fd4), /* power down RSSI circuit */
    277	};
    278
    279	return zd_rfwritev_locked(chip, rv, ARRAY_SIZE(rv), RF_RV_BITS);
    280}
    281
    282static int uw2453_set_tx_gain_level(struct zd_chip *chip, int channel)
    283{
    284	u8 int_value = chip->pwr_int_values[channel - 1];
    285
    286	if (int_value >= ARRAY_SIZE(uw2453_txgain)) {
    287		dev_dbg_f(zd_chip_dev(chip), "can't configure TX gain for "
    288			  "int value %x on channel %d\n", int_value, channel);
    289		return 0;
    290	}
    291
    292	return zd_rfwrite_locked(chip,
    293		UW2453_REGWRITE(7, uw2453_txgain[int_value]), RF_RV_BITS);
    294}
    295
    296static int uw2453_init_hw(struct zd_rf *rf)
    297{
    298	int i, r;
    299	int found_config = -1;
    300	u16 intr_status;
    301	struct zd_chip *chip = zd_rf_to_chip(rf);
    302
    303	static const struct zd_ioreq16 ioreqs[] = {
    304		{ ZD_CR10,  0x89 }, { ZD_CR15,  0x20 },
    305		{ ZD_CR17,  0x28 }, /* 6112 no change */
    306		{ ZD_CR23,  0x38 }, { ZD_CR24,  0x20 }, { ZD_CR26,  0x93 },
    307		{ ZD_CR27,  0x15 }, { ZD_CR28,  0x3e }, { ZD_CR29,  0x00 },
    308		{ ZD_CR33,  0x28 }, { ZD_CR34,  0x30 },
    309		{ ZD_CR35,  0x43 }, /* 6112 3e->43 */
    310		{ ZD_CR41,  0x24 }, { ZD_CR44,  0x32 },
    311		{ ZD_CR46,  0x92 }, /* 6112 96->92 */
    312		{ ZD_CR47,  0x1e },
    313		{ ZD_CR48,  0x04 }, /* 5602 Roger */
    314		{ ZD_CR49,  0xfa }, { ZD_CR79,  0x58 }, { ZD_CR80,  0x30 },
    315		{ ZD_CR81,  0x30 }, { ZD_CR87,  0x0a }, { ZD_CR89,  0x04 },
    316		{ ZD_CR91,  0x00 }, { ZD_CR92,  0x0a }, { ZD_CR98,  0x8d },
    317		{ ZD_CR99,  0x28 }, { ZD_CR100, 0x02 },
    318		{ ZD_CR101, 0x09 }, /* 6112 13->1f 6220 1f->13 6407 13->9 */
    319		{ ZD_CR102, 0x27 },
    320		{ ZD_CR106, 0x1c }, /* 5d07 5112 1f->1c 6220 1c->1f
    321				     * 6221 1f->1c
    322				     */
    323		{ ZD_CR107, 0x1c }, /* 6220 1c->1a 5221 1a->1c */
    324		{ ZD_CR109, 0x13 },
    325		{ ZD_CR110, 0x1f }, /* 6112 13->1f 6221 1f->13 6407 13->0x09 */
    326		{ ZD_CR111, 0x13 }, { ZD_CR112, 0x1f }, { ZD_CR113, 0x27 },
    327		{ ZD_CR114, 0x23 }, /* 6221 27->23 */
    328		{ ZD_CR115, 0x24 }, /* 6112 24->1c 6220 1c->24 */
    329		{ ZD_CR116, 0x24 }, /* 6220 1c->24 */
    330		{ ZD_CR117, 0xfa }, /* 6112 fa->f8 6220 f8->f4 6220 f4->fa */
    331		{ ZD_CR118, 0xf0 }, /* 5d07 6112 f0->f2 6220 f2->f0 */
    332		{ ZD_CR119, 0x1a }, /* 6112 1a->10 6220 10->14 6220 14->1a */
    333		{ ZD_CR120, 0x4f },
    334		{ ZD_CR121, 0x1f }, /* 6220 4f->1f */
    335		{ ZD_CR122, 0xf0 }, { ZD_CR123, 0x57 }, { ZD_CR125, 0xad },
    336		{ ZD_CR126, 0x6c }, { ZD_CR127, 0x03 },
    337		{ ZD_CR128, 0x14 }, /* 6302 12->11 */
    338		{ ZD_CR129, 0x12 }, /* 6301 10->0f */
    339		{ ZD_CR130, 0x10 }, { ZD_CR137, 0x50 }, { ZD_CR138, 0xa8 },
    340		{ ZD_CR144, 0xac }, { ZD_CR146, 0x20 }, { ZD_CR252, 0xff },
    341		{ ZD_CR253, 0xff },
    342	};
    343
    344	static const u32 rv[] = {
    345		UW2453_REGWRITE(4, 0x2b),    /* configure receiver gain */
    346		UW2453_REGWRITE(5, 0x19e4f), /* configure transmitter gain */
    347		UW2453_REGWRITE(6, 0xf81ad), /* enable RX/TX filter tuning */
    348		UW2453_REGWRITE(7, 0x3fffe), /* disable TX gain in test mode */
    349
    350		/* enter CAL_FIL mode, TX gain set by registers, RX gain set by pins,
    351		 * RSSI circuit powered down, reduced RSSI range */
    352		UW2453_REGWRITE(0, 0x25f9c), /* 5d01 cal_fil */
    353
    354		/* synthesizer configuration for channel 1 */
    355		UW2453_REGWRITE(1, 0x47),
    356		UW2453_REGWRITE(2, 0x999),
    357
    358		/* disable manual VCO band selection */
    359		UW2453_REGWRITE(3, 0x7602),
    360
    361		/* enable manual VCO band selection, configure current level */
    362		UW2453_REGWRITE(3, 0x46063),
    363	};
    364
    365	r = zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
    366	if (r)
    367		return r;
    368
    369	r = zd_rfwritev_locked(chip, rv, ARRAY_SIZE(rv), RF_RV_BITS);
    370	if (r)
    371		return r;
    372
    373	r = uw2453_init_mode(chip);
    374	if (r)
    375		return r;
    376
    377	/* Try all standard VCO configuration settings on channel 1 */
    378	for (i = 0; i < ARRAY_SIZE(uw2453_std_vco_cfg) - 1; i++) {
    379		/* Configure synthesizer for channel 1 */
    380		r = uw2453_synth_set_channel(chip, 1, false);
    381		if (r)
    382			return r;
    383
    384		/* Write VCO config */
    385		r = uw2453_write_vco_cfg(chip, uw2453_std_vco_cfg[i][0]);
    386		if (r)
    387			return r;
    388
    389		/* ack interrupt event */
    390		r = zd_iowrite16_locked(chip, 0x0f, UW2453_INTR_REG);
    391		if (r)
    392			return r;
    393
    394		/* check interrupt status */
    395		r = zd_ioread16_locked(chip, &intr_status, UW2453_INTR_REG);
    396		if (r)
    397			return r;
    398
    399		if (!(intr_status & 0xf)) {
    400			dev_dbg_f(zd_chip_dev(chip),
    401				"PLL locked on configuration %d\n", i);
    402			found_config = i;
    403			break;
    404		}
    405	}
    406
    407	if (found_config == -1) {
    408		/* autocal */
    409		dev_dbg_f(zd_chip_dev(chip),
    410			"PLL did not lock, using autocal\n");
    411
    412		r = uw2453_synth_set_channel(chip, 1, true);
    413		if (r)
    414			return r;
    415
    416		r = uw2453_write_vco_cfg(chip, UW2453_AUTOCAL_VCO_CFG);
    417		if (r)
    418			return r;
    419	}
    420
    421	/* To match the vendor driver behaviour, we use the configuration after
    422	 * the one that produced a lock. */
    423	UW2453_PRIV(rf)->config = found_config + 1;
    424
    425	return zd_iowrite16_locked(chip, 0x06, ZD_CR203);
    426}
    427
    428static int uw2453_set_channel(struct zd_rf *rf, u8 channel)
    429{
    430	int r;
    431	u16 vco_cfg;
    432	int config = UW2453_PRIV(rf)->config;
    433	bool autocal = (config == -1);
    434	struct zd_chip *chip = zd_rf_to_chip(rf);
    435
    436	static const struct zd_ioreq16 ioreqs[] = {
    437		{ ZD_CR80,  0x30 }, { ZD_CR81,  0x30 }, { ZD_CR79,  0x58 },
    438		{ ZD_CR12,  0xf0 }, { ZD_CR77,  0x1b }, { ZD_CR78,  0x58 },
    439	};
    440
    441	r = uw2453_synth_set_channel(chip, channel, autocal);
    442	if (r)
    443		return r;
    444
    445	if (autocal)
    446		vco_cfg = UW2453_AUTOCAL_VCO_CFG;
    447	else
    448		vco_cfg = uw2453_std_vco_cfg[config][CHAN_TO_PAIRIDX(channel)];
    449
    450	r = uw2453_write_vco_cfg(chip, vco_cfg);
    451	if (r)
    452		return r;
    453
    454	r = uw2453_init_mode(chip);
    455	if (r)
    456		return r;
    457
    458	r = zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
    459	if (r)
    460		return r;
    461
    462	r = uw2453_set_tx_gain_level(chip, channel);
    463	if (r)
    464		return r;
    465
    466	return zd_iowrite16_locked(chip, 0x06, ZD_CR203);
    467}
    468
    469static int uw2453_switch_radio_on(struct zd_rf *rf)
    470{
    471	int r;
    472	struct zd_chip *chip = zd_rf_to_chip(rf);
    473	struct zd_ioreq16 ioreqs[] = {
    474		{ ZD_CR11,  0x00 }, { ZD_CR251, 0x3f },
    475	};
    476
    477	/* enter RXTX mode */
    478	r = zd_rfwrite_locked(chip, UW2453_REGWRITE(0, 0x25f94), RF_RV_BITS);
    479	if (r)
    480		return r;
    481
    482	if (zd_chip_is_zd1211b(chip))
    483		ioreqs[1].value = 0x7f;
    484
    485	return zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
    486}
    487
    488static int uw2453_switch_radio_off(struct zd_rf *rf)
    489{
    490	int r;
    491	struct zd_chip *chip = zd_rf_to_chip(rf);
    492	static const struct zd_ioreq16 ioreqs[] = {
    493		{ ZD_CR11,  0x04 }, { ZD_CR251, 0x2f },
    494	};
    495
    496	/* enter IDLE mode */
    497	/* FIXME: shouldn't we go to SLEEP? sent email to zydas */
    498	r = zd_rfwrite_locked(chip, UW2453_REGWRITE(0, 0x25f90), RF_RV_BITS);
    499	if (r)
    500		return r;
    501
    502	return zd_iowrite16a_locked(chip, ioreqs, ARRAY_SIZE(ioreqs));
    503}
    504
    505static void uw2453_clear(struct zd_rf *rf)
    506{
    507	kfree(rf->priv);
    508}
    509
    510int zd_rf_init_uw2453(struct zd_rf *rf)
    511{
    512	rf->init_hw = uw2453_init_hw;
    513	rf->set_channel = uw2453_set_channel;
    514	rf->switch_radio_on = uw2453_switch_radio_on;
    515	rf->switch_radio_off = uw2453_switch_radio_off;
    516	rf->patch_6m_band_edge = zd_rf_generic_patch_6m;
    517	rf->clear = uw2453_clear;
    518	/* we have our own TX integration code */
    519	rf->update_channel_int = 0;
    520
    521	rf->priv = kmalloc(sizeof(struct uw2453_priv), GFP_KERNEL);
    522	if (rf->priv == NULL)
    523		return -ENOMEM;
    524
    525	return 0;
    526}
    527