hwmon: (adt7475) fan stall prevention
[linux/fpc-iii.git] / drivers / nfc / trf7970a.c
blob2d1c8ca6e67907002a05d284316925b951d178de
1 /*
2 * TI TRF7970a RFID/NFC Transceiver Driver
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
6 * Author: Erick Macias <emacias@ti.com>
7 * Author: Felipe Balbi <balbi@ti.com>
8 * Author: Mark A. Greer <mgreer@animalcreek.com>
10 * This program is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 of
12 * the License as published by the Free Software Foundation.
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <linux/netdevice.h>
18 #include <linux/interrupt.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/nfc.h>
21 #include <linux/skbuff.h>
22 #include <linux/delay.h>
23 #include <linux/gpio.h>
24 #include <linux/of.h>
25 #include <linux/of_gpio.h>
26 #include <linux/spi/spi.h>
27 #include <linux/regulator/consumer.h>
29 #include <net/nfc/nfc.h>
30 #include <net/nfc/digital.h>
32 /* There are 3 ways the host can communicate with the trf7970a:
33 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
34 * SS mode. The driver only supports the two SPI modes.
36 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
37 * pins must asserted in that order and with specific delays in between.
38 * The delays used in the driver were provided by TI and have been
39 * confirmed to work with this driver. There is a bug with the current
40 * version of the trf7970a that requires that EN2 remain low no matter
41 * what. If it goes high, it will generate an RF field even when in
42 * passive target mode. TI has indicated that the chip will work okay
43 * when EN2 is left low. The 'en2-rf-quirk' device tree property
44 * indicates that trf7970a currently being used has the erratum and
45 * that EN2 must be kept low.
47 * Timeouts are implemented using the delayed workqueue kernel facility.
48 * Timeouts are required so things don't hang when there is no response
49 * from the trf7970a (or tag). Using this mechanism creates a race with
50 * interrupts, however. That is, an interrupt and a timeout could occur
51 * closely enough together that one is blocked by the mutex while the other
52 * executes. When the timeout handler executes first and blocks the
53 * interrupt handler, it will eventually set the state to IDLE so the
54 * interrupt handler will check the state and exit with no harm done.
55 * When the interrupt handler executes first and blocks the timeout handler,
56 * the cancel_delayed_work() call will know that it didn't cancel the
57 * work item (i.e., timeout) and will return zero. That return code is
58 * used by the timer handler to indicate that it should ignore the timeout
59 * once its unblocked.
61 * Aborting an active command isn't as simple as it seems because the only
62 * way to abort a command that's already been sent to the tag is so turn
63 * off power to the tag. If we do that, though, we'd have to go through
64 * the entire anticollision procedure again but the digital layer doesn't
65 * support that. So, if an abort is received before trf7970a_send_cmd()
66 * has sent the command to the tag, it simply returns -ECANCELED. If the
67 * command has already been sent to the tag, then the driver continues
68 * normally and recieves the response data (or error) but just before
69 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
70 * upstream instead. If the command failed, that error will be sent
71 * upstream.
73 * When recieving data from a tag and the interrupt status register has
74 * only the SRX bit set, it means that all of the data has been received
75 * (once what's in the fifo has been read). However, depending on timing
76 * an interrupt status with only the SRX bit set may not be recived. In
77 * those cases, the timeout mechanism is used to wait 20 ms in case more
78 * data arrives. After 20 ms, it is assumed that all of the data has been
79 * received and the accumulated rx data is sent upstream. The
80 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
81 * (i.e., it indicates that some data has been received but we're not sure
82 * if there is more coming so a timeout in this state means all data has
83 * been received and there isn't an error). The delay is 20 ms since delays
84 * of ~16 ms have been observed during testing.
86 * When transmitting a frame larger than the FIFO size (127 bytes), the
87 * driver will wait 20 ms for the FIFO to drain past the low-watermark
88 * and generate an interrupt. The low-watermark set to 32 bytes so the
89 * interrupt should fire after 127 - 32 = 95 bytes have been sent. At
90 * the lowest possible bit rate (6.62 kbps for 15693), it will take up
91 * to ~14.35 ms so 20 ms is used for the timeout.
93 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
94 * Having only 4 bits in the FIFO won't normally generate an interrupt so
95 * driver enables the '4_bit_RX' bit of the Special Functions register 1
96 * to cause an interrupt in that case. Leaving that bit for a read command
97 * messes up the data returned so it is only enabled when the framing is
98 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
99 * Unfortunately, that means that the driver has to peek into tx frames
100 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'. This is done by
101 * the trf7970a_per_cmd_config() routine.
103 * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
104 * frequencies and whether to use low or high data rates in the flags byte
105 * of the frame. This means that the driver has to peek at all 15693 frames
106 * to determine what speed to set the communication to. In addition, write
107 * and lock commands use the OPTION flag to indicate that an EOF must be
108 * sent to the tag before it will send its response. So the driver has to
109 * examine all frames for that reason too.
111 * It is unclear how long to wait before sending the EOF. According to the
112 * Note under Table 1-1 in section 1.6 of
113 * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
114 * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
115 * enough so 20 ms is used. So the timer is set to 40 ms - 20 ms to drain
116 * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
117 * ensure the wait is long enough before sending the EOF. This seems to work
118 * reliably.
121 #define TRF7970A_SUPPORTED_PROTOCOLS \
122 (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK | \
123 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
124 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
126 #define TRF7970A_AUTOSUSPEND_DELAY 30000 /* 30 seconds */
127 #define TRF7970A_13MHZ_CLOCK_FREQUENCY 13560000
128 #define TRF7970A_27MHZ_CLOCK_FREQUENCY 27120000
131 #define TRF7970A_RX_SKB_ALLOC_SIZE 256
133 #define TRF7970A_FIFO_SIZE 127
135 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
136 #define TRF7970A_TX_MAX (4096 - 1)
138 #define TRF7970A_WAIT_FOR_TX_IRQ 20
139 #define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT 20
140 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT 20
141 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF 40
143 /* Guard times for various RF technologies (in us) */
144 #define TRF7970A_GUARD_TIME_NFCA 5000
145 #define TRF7970A_GUARD_TIME_NFCB 5000
146 #define TRF7970A_GUARD_TIME_NFCF 20000
147 #define TRF7970A_GUARD_TIME_15693 1000
149 /* Quirks */
150 /* Erratum: When reading IRQ Status register on trf7970a, we must issue a
151 * read continuous command for IRQ Status and Collision Position registers.
153 #define TRF7970A_QUIRK_IRQ_STATUS_READ BIT(0)
154 #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW BIT(1)
155 #define TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE BIT(2)
157 /* Direct commands */
158 #define TRF7970A_CMD_IDLE 0x00
159 #define TRF7970A_CMD_SOFT_INIT 0x03
160 #define TRF7970A_CMD_RF_COLLISION 0x04
161 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_N 0x05
162 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_0 0x06
163 #define TRF7970A_CMD_FIFO_RESET 0x0f
164 #define TRF7970A_CMD_TRANSMIT_NO_CRC 0x10
165 #define TRF7970A_CMD_TRANSMIT 0x11
166 #define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC 0x12
167 #define TRF7970A_CMD_DELAY_TRANSMIT 0x13
168 #define TRF7970A_CMD_EOF 0x14
169 #define TRF7970A_CMD_CLOSE_SLOT 0x15
170 #define TRF7970A_CMD_BLOCK_RX 0x16
171 #define TRF7970A_CMD_ENABLE_RX 0x17
172 #define TRF7970A_CMD_TEST_INT_RF 0x18
173 #define TRF7970A_CMD_TEST_EXT_RF 0x19
174 #define TRF7970A_CMD_RX_GAIN_ADJUST 0x1a
176 /* Bits determining whether its a direct command or register R/W,
177 * whether to use a continuous SPI transaction or not, and the actual
178 * direct cmd opcode or regster address.
180 #define TRF7970A_CMD_BIT_CTRL BIT(7)
181 #define TRF7970A_CMD_BIT_RW BIT(6)
182 #define TRF7970A_CMD_BIT_CONTINUOUS BIT(5)
183 #define TRF7970A_CMD_BIT_OPCODE(opcode) ((opcode) & 0x1f)
185 /* Registers addresses */
186 #define TRF7970A_CHIP_STATUS_CTRL 0x00
187 #define TRF7970A_ISO_CTRL 0x01
188 #define TRF7970A_ISO14443B_TX_OPTIONS 0x02
189 #define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
190 #define TRF7970A_TX_TIMER_SETTING_H_BYTE 0x04
191 #define TRF7970A_TX_TIMER_SETTING_L_BYTE 0x05
192 #define TRF7970A_TX_PULSE_LENGTH_CTRL 0x06
193 #define TRF7970A_RX_NO_RESPONSE_WAIT 0x07
194 #define TRF7970A_RX_WAIT_TIME 0x08
195 #define TRF7970A_MODULATOR_SYS_CLK_CTRL 0x09
196 #define TRF7970A_RX_SPECIAL_SETTINGS 0x0a
197 #define TRF7970A_REG_IO_CTRL 0x0b
198 #define TRF7970A_IRQ_STATUS 0x0c
199 #define TRF7970A_COLLISION_IRQ_MASK 0x0d
200 #define TRF7970A_COLLISION_POSITION 0x0e
201 #define TRF7970A_RSSI_OSC_STATUS 0x0f
202 #define TRF7970A_SPECIAL_FCN_REG1 0x10
203 #define TRF7970A_SPECIAL_FCN_REG2 0x11
204 #define TRF7970A_RAM1 0x12
205 #define TRF7970A_RAM2 0x13
206 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS 0x14
207 #define TRF7970A_NFC_LOW_FIELD_LEVEL 0x16
208 #define TRF7970A_NFCID1 0x17
209 #define TRF7970A_NFC_TARGET_LEVEL 0x18
210 #define TRF79070A_NFC_TARGET_PROTOCOL 0x19
211 #define TRF7970A_TEST_REGISTER1 0x1a
212 #define TRF7970A_TEST_REGISTER2 0x1b
213 #define TRF7970A_FIFO_STATUS 0x1c
214 #define TRF7970A_TX_LENGTH_BYTE1 0x1d
215 #define TRF7970A_TX_LENGTH_BYTE2 0x1e
216 #define TRF7970A_FIFO_IO_REGISTER 0x1f
218 /* Chip Status Control Register Bits */
219 #define TRF7970A_CHIP_STATUS_VRS5_3 BIT(0)
220 #define TRF7970A_CHIP_STATUS_REC_ON BIT(1)
221 #define TRF7970A_CHIP_STATUS_AGC_ON BIT(2)
222 #define TRF7970A_CHIP_STATUS_PM_ON BIT(3)
223 #define TRF7970A_CHIP_STATUS_RF_PWR BIT(4)
224 #define TRF7970A_CHIP_STATUS_RF_ON BIT(5)
225 #define TRF7970A_CHIP_STATUS_DIRECT BIT(6)
226 #define TRF7970A_CHIP_STATUS_STBY BIT(7)
228 /* ISO Control Register Bits */
229 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662 0x00
230 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662 0x01
231 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648 0x02
232 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
233 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a 0x04
234 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667 0x05
235 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669 0x06
236 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
237 #define TRF7970A_ISO_CTRL_14443A_106 0x08
238 #define TRF7970A_ISO_CTRL_14443A_212 0x09
239 #define TRF7970A_ISO_CTRL_14443A_424 0x0a
240 #define TRF7970A_ISO_CTRL_14443A_848 0x0b
241 #define TRF7970A_ISO_CTRL_14443B_106 0x0c
242 #define TRF7970A_ISO_CTRL_14443B_212 0x0d
243 #define TRF7970A_ISO_CTRL_14443B_424 0x0e
244 #define TRF7970A_ISO_CTRL_14443B_848 0x0f
245 #define TRF7970A_ISO_CTRL_FELICA_212 0x1a
246 #define TRF7970A_ISO_CTRL_FELICA_424 0x1b
247 #define TRF7970A_ISO_CTRL_NFC_NFCA_106 0x01
248 #define TRF7970A_ISO_CTRL_NFC_NFCF_212 0x02
249 #define TRF7970A_ISO_CTRL_NFC_NFCF_424 0x03
250 #define TRF7970A_ISO_CTRL_NFC_CE_14443A 0x00
251 #define TRF7970A_ISO_CTRL_NFC_CE_14443B 0x01
252 #define TRF7970A_ISO_CTRL_NFC_CE BIT(2)
253 #define TRF7970A_ISO_CTRL_NFC_ACTIVE BIT(3)
254 #define TRF7970A_ISO_CTRL_NFC_INITIATOR BIT(4)
255 #define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE BIT(5)
256 #define TRF7970A_ISO_CTRL_RFID BIT(5)
257 #define TRF7970A_ISO_CTRL_DIR_MODE BIT(6)
258 #define TRF7970A_ISO_CTRL_RX_CRC_N BIT(7) /* true == No CRC */
260 #define TRF7970A_ISO_CTRL_RFID_SPEED_MASK 0x1f
262 /* Modulator and SYS_CLK Control Register Bits */
263 #define TRF7970A_MODULATOR_DEPTH(n) ((n) & 0x7)
264 #define TRF7970A_MODULATOR_DEPTH_ASK10 (TRF7970A_MODULATOR_DEPTH(0))
265 #define TRF7970A_MODULATOR_DEPTH_OOK (TRF7970A_MODULATOR_DEPTH(1))
266 #define TRF7970A_MODULATOR_DEPTH_ASK7 (TRF7970A_MODULATOR_DEPTH(2))
267 #define TRF7970A_MODULATOR_DEPTH_ASK8_5 (TRF7970A_MODULATOR_DEPTH(3))
268 #define TRF7970A_MODULATOR_DEPTH_ASK13 (TRF7970A_MODULATOR_DEPTH(4))
269 #define TRF7970A_MODULATOR_DEPTH_ASK16 (TRF7970A_MODULATOR_DEPTH(5))
270 #define TRF7970A_MODULATOR_DEPTH_ASK22 (TRF7970A_MODULATOR_DEPTH(6))
271 #define TRF7970A_MODULATOR_DEPTH_ASK30 (TRF7970A_MODULATOR_DEPTH(7))
272 #define TRF7970A_MODULATOR_EN_ANA BIT(3)
273 #define TRF7970A_MODULATOR_CLK(n) (((n) & 0x3) << 4)
274 #define TRF7970A_MODULATOR_CLK_DISABLED (TRF7970A_MODULATOR_CLK(0))
275 #define TRF7970A_MODULATOR_CLK_3_6 (TRF7970A_MODULATOR_CLK(1))
276 #define TRF7970A_MODULATOR_CLK_6_13 (TRF7970A_MODULATOR_CLK(2))
277 #define TRF7970A_MODULATOR_CLK_13_27 (TRF7970A_MODULATOR_CLK(3))
278 #define TRF7970A_MODULATOR_EN_OOK BIT(6)
279 #define TRF7970A_MODULATOR_27MHZ BIT(7)
281 #define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM BIT(0)
282 #define TRF7970A_RX_SPECIAL_SETTINGS_AGCR BIT(1)
283 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB (0x0 << 2)
284 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB (0x1 << 2)
285 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB (0x2 << 2)
286 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB (0x3 << 2)
287 #define TRF7970A_RX_SPECIAL_SETTINGS_HBT BIT(4)
288 #define TRF7970A_RX_SPECIAL_SETTINGS_M848 BIT(5)
289 #define TRF7970A_RX_SPECIAL_SETTINGS_C424 BIT(6)
290 #define TRF7970A_RX_SPECIAL_SETTINGS_C212 BIT(7)
292 #define TRF7970A_REG_IO_CTRL_VRS(v) ((v) & 0x07)
293 #define TRF7970A_REG_IO_CTRL_IO_LOW BIT(5)
294 #define TRF7970A_REG_IO_CTRL_EN_EXT_PA BIT(6)
295 #define TRF7970A_REG_IO_CTRL_AUTO_REG BIT(7)
297 /* IRQ Status Register Bits */
298 #define TRF7970A_IRQ_STATUS_NORESP BIT(0) /* ISO15693 only */
299 #define TRF7970A_IRQ_STATUS_NFC_COL_ERROR BIT(0)
300 #define TRF7970A_IRQ_STATUS_COL BIT(1)
301 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR BIT(2)
302 #define TRF7970A_IRQ_STATUS_NFC_RF BIT(2)
303 #define TRF7970A_IRQ_STATUS_PARITY_ERROR BIT(3)
304 #define TRF7970A_IRQ_STATUS_NFC_SDD BIT(3)
305 #define TRF7970A_IRQ_STATUS_CRC_ERROR BIT(4)
306 #define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR BIT(4)
307 #define TRF7970A_IRQ_STATUS_FIFO BIT(5)
308 #define TRF7970A_IRQ_STATUS_SRX BIT(6)
309 #define TRF7970A_IRQ_STATUS_TX BIT(7)
311 #define TRF7970A_IRQ_STATUS_ERROR \
312 (TRF7970A_IRQ_STATUS_COL | \
313 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR | \
314 TRF7970A_IRQ_STATUS_PARITY_ERROR | \
315 TRF7970A_IRQ_STATUS_CRC_ERROR)
317 #define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK (BIT(2) | BIT(1) | BIT(0))
318 #define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK (BIT(5) | BIT(4) | BIT(3))
319 #define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK BIT(6)
321 #define TRF7970A_SPECIAL_FCN_REG1_COL_7_6 BIT(0)
322 #define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL BIT(1)
323 #define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX BIT(2)
324 #define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE BIT(3)
325 #define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US BIT(4)
326 #define TRF7970A_SPECIAL_FCN_REG1_PAR43 BIT(5)
328 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124 (0x0 << 2)
329 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120 (0x1 << 2)
330 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112 (0x2 << 2)
331 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 (0x3 << 2)
332 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4 0x0
333 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8 0x1
334 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16 0x2
335 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32 0x3
337 #define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v) ((v) & 0x07)
338 #define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS BIT(7)
340 #define TRF7970A_NFC_TARGET_LEVEL_RFDET(v) ((v) & 0x07)
341 #define TRF7970A_NFC_TARGET_LEVEL_HI_RF BIT(3)
342 #define TRF7970A_NFC_TARGET_LEVEL_SDD_EN BIT(5)
343 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES (0x0 << 6)
344 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES (0x1 << 6)
345 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES (0x2 << 6)
347 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106 BIT(0)
348 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212 BIT(1)
349 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424 (BIT(0) | BIT(1))
350 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B BIT(2)
351 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 BIT(3)
352 #define TRF79070A_NFC_TARGET_PROTOCOL_FELICA BIT(4)
353 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_L BIT(6)
354 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_H BIT(7)
356 #define TRF79070A_NFC_TARGET_PROTOCOL_106A \
357 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
358 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
359 TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 | \
360 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
362 #define TRF79070A_NFC_TARGET_PROTOCOL_106B \
363 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
364 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
365 TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B | \
366 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
368 #define TRF79070A_NFC_TARGET_PROTOCOL_212F \
369 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
370 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
371 TRF79070A_NFC_TARGET_PROTOCOL_FELICA | \
372 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
374 #define TRF79070A_NFC_TARGET_PROTOCOL_424F \
375 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
376 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
377 TRF79070A_NFC_TARGET_PROTOCOL_FELICA | \
378 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
380 #define TRF7970A_FIFO_STATUS_OVERFLOW BIT(7)
382 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
383 #define NFC_T2T_CMD_READ 0x30
385 /* ISO 15693 commands codes */
386 #define ISO15693_CMD_INVENTORY 0x01
387 #define ISO15693_CMD_READ_SINGLE_BLOCK 0x20
388 #define ISO15693_CMD_WRITE_SINGLE_BLOCK 0x21
389 #define ISO15693_CMD_LOCK_BLOCK 0x22
390 #define ISO15693_CMD_READ_MULTIPLE_BLOCK 0x23
391 #define ISO15693_CMD_WRITE_MULTIPLE_BLOCK 0x24
392 #define ISO15693_CMD_SELECT 0x25
393 #define ISO15693_CMD_RESET_TO_READY 0x26
394 #define ISO15693_CMD_WRITE_AFI 0x27
395 #define ISO15693_CMD_LOCK_AFI 0x28
396 #define ISO15693_CMD_WRITE_DSFID 0x29
397 #define ISO15693_CMD_LOCK_DSFID 0x2a
398 #define ISO15693_CMD_GET_SYSTEM_INFO 0x2b
399 #define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS 0x2c
401 /* ISO 15693 request and response flags */
402 #define ISO15693_REQ_FLAG_SUB_CARRIER BIT(0)
403 #define ISO15693_REQ_FLAG_DATA_RATE BIT(1)
404 #define ISO15693_REQ_FLAG_INVENTORY BIT(2)
405 #define ISO15693_REQ_FLAG_PROTOCOL_EXT BIT(3)
406 #define ISO15693_REQ_FLAG_SELECT BIT(4)
407 #define ISO15693_REQ_FLAG_AFI BIT(4)
408 #define ISO15693_REQ_FLAG_ADDRESS BIT(5)
409 #define ISO15693_REQ_FLAG_NB_SLOTS BIT(5)
410 #define ISO15693_REQ_FLAG_OPTION BIT(6)
412 #define ISO15693_REQ_FLAG_SPEED_MASK \
413 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
415 enum trf7970a_state {
416 TRF7970A_ST_PWR_OFF,
417 TRF7970A_ST_RF_OFF,
418 TRF7970A_ST_IDLE,
419 TRF7970A_ST_IDLE_RX_BLOCKED,
420 TRF7970A_ST_WAIT_FOR_TX_FIFO,
421 TRF7970A_ST_WAIT_FOR_RX_DATA,
422 TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
423 TRF7970A_ST_WAIT_TO_ISSUE_EOF,
424 TRF7970A_ST_LISTENING,
425 TRF7970A_ST_LISTENING_MD,
426 TRF7970A_ST_MAX
429 struct trf7970a {
430 enum trf7970a_state state;
431 struct device *dev;
432 struct spi_device *spi;
433 struct regulator *regulator;
434 struct nfc_digital_dev *ddev;
435 u32 quirks;
436 bool is_initiator;
437 bool aborting;
438 struct sk_buff *tx_skb;
439 struct sk_buff *rx_skb;
440 nfc_digital_cmd_complete_t cb;
441 void *cb_arg;
442 u8 chip_status_ctrl;
443 u8 iso_ctrl;
444 u8 iso_ctrl_tech;
445 u8 modulator_sys_clk_ctrl;
446 u8 special_fcn_reg1;
447 u8 io_ctrl;
448 unsigned int guard_time;
449 int technology;
450 int framing;
451 u8 md_rf_tech;
452 u8 tx_cmd;
453 bool issue_eof;
454 bool adjust_resp_len;
455 int en2_gpio;
456 int en_gpio;
457 struct mutex lock;
458 unsigned int timeout;
459 bool ignore_timeout;
460 struct delayed_work timeout_work;
464 static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
466 u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
467 int ret;
469 dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
471 ret = spi_write(trf->spi, &cmd, 1);
472 if (ret)
473 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
474 ret);
475 return ret;
478 static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
480 u8 addr = TRF7970A_CMD_BIT_RW | reg;
481 int ret;
483 ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
484 if (ret)
485 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
486 ret);
488 dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
490 return ret;
493 static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len)
495 u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
496 struct spi_transfer t[2];
497 struct spi_message m;
498 int ret;
500 dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
502 spi_message_init(&m);
504 memset(&t, 0, sizeof(t));
506 t[0].tx_buf = &addr;
507 t[0].len = sizeof(addr);
508 spi_message_add_tail(&t[0], &m);
510 t[1].rx_buf = buf;
511 t[1].len = len;
512 spi_message_add_tail(&t[1], &m);
514 ret = spi_sync(trf->spi, &m);
515 if (ret)
516 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
517 ret);
518 return ret;
521 static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
523 u8 buf[2] = { reg, val };
524 int ret;
526 dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
528 ret = spi_write(trf->spi, buf, 2);
529 if (ret)
530 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
531 buf[0], buf[1], ret);
533 return ret;
536 static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
538 int ret;
539 u8 buf[2];
540 u8 addr;
542 addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
544 if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
545 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
546 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
547 } else {
548 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
551 if (ret)
552 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
553 __func__, ret);
554 else
555 *status = buf[0];
557 return ret;
560 static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
562 int ret;
563 u8 buf[2];
564 u8 addr;
566 addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
567 TRF7970A_CMD_BIT_CONTINUOUS;
569 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
570 if (ret)
571 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
572 __func__, ret);
573 else
574 *target_proto = buf[0];
576 return ret;
579 static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
581 int ret;
582 u8 target_proto, tech;
584 ret = trf7970a_read_target_proto(trf, &target_proto);
585 if (ret)
586 return ret;
588 switch (target_proto) {
589 case TRF79070A_NFC_TARGET_PROTOCOL_106A:
590 tech = NFC_DIGITAL_RF_TECH_106A;
591 break;
592 case TRF79070A_NFC_TARGET_PROTOCOL_106B:
593 tech = NFC_DIGITAL_RF_TECH_106B;
594 break;
595 case TRF79070A_NFC_TARGET_PROTOCOL_212F:
596 tech = NFC_DIGITAL_RF_TECH_212F;
597 break;
598 case TRF79070A_NFC_TARGET_PROTOCOL_424F:
599 tech = NFC_DIGITAL_RF_TECH_424F;
600 break;
601 default:
602 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
603 __func__, target_proto);
604 return -EIO;
607 *rf_tech = tech;
609 return ret;
612 static void trf7970a_send_upstream(struct trf7970a *trf)
614 dev_kfree_skb_any(trf->tx_skb);
615 trf->tx_skb = NULL;
617 if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
618 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
619 16, 1, trf->rx_skb->data, trf->rx_skb->len,
620 false);
622 trf->state = TRF7970A_ST_IDLE;
624 if (trf->aborting) {
625 dev_dbg(trf->dev, "Abort process complete\n");
627 if (!IS_ERR(trf->rx_skb)) {
628 kfree_skb(trf->rx_skb);
629 trf->rx_skb = ERR_PTR(-ECANCELED);
632 trf->aborting = false;
635 if (trf->adjust_resp_len) {
636 if (trf->rx_skb)
637 skb_trim(trf->rx_skb, trf->rx_skb->len - 1);
639 trf->adjust_resp_len = false;
642 trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
644 trf->rx_skb = NULL;
647 static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
649 dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
651 cancel_delayed_work(&trf->timeout_work);
653 kfree_skb(trf->rx_skb);
654 trf->rx_skb = ERR_PTR(errno);
656 trf7970a_send_upstream(trf);
659 static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
660 unsigned int len, u8 *prefix, unsigned int prefix_len)
662 struct spi_transfer t[2];
663 struct spi_message m;
664 unsigned int timeout;
665 int ret;
667 print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
668 16, 1, skb->data, len, false);
670 spi_message_init(&m);
672 memset(&t, 0, sizeof(t));
674 t[0].tx_buf = prefix;
675 t[0].len = prefix_len;
676 spi_message_add_tail(&t[0], &m);
678 t[1].tx_buf = skb->data;
679 t[1].len = len;
680 spi_message_add_tail(&t[1], &m);
682 ret = spi_sync(trf->spi, &m);
683 if (ret) {
684 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
685 ret);
686 return ret;
689 skb_pull(skb, len);
691 if (skb->len > 0) {
692 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
693 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
694 } else {
695 if (trf->issue_eof) {
696 trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
697 timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
698 } else {
699 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
701 if (!trf->timeout)
702 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
703 else
704 timeout = trf->timeout;
708 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
709 trf->state);
711 schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
713 return 0;
716 static void trf7970a_fill_fifo(struct trf7970a *trf)
718 struct sk_buff *skb = trf->tx_skb;
719 unsigned int len;
720 int ret;
721 u8 fifo_bytes;
722 u8 prefix;
724 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
725 if (ret) {
726 trf7970a_send_err_upstream(trf, ret);
727 return;
730 dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
732 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
734 /* Calculate how much more data can be written to the fifo */
735 len = TRF7970A_FIFO_SIZE - fifo_bytes;
736 if (!len) {
737 schedule_delayed_work(&trf->timeout_work,
738 msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
739 return;
742 len = min(skb->len, len);
744 prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
746 ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
747 if (ret)
748 trf7970a_send_err_upstream(trf, ret);
751 static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
753 struct sk_buff *skb = trf->rx_skb;
754 int ret;
755 u8 fifo_bytes;
757 if (status & TRF7970A_IRQ_STATUS_ERROR) {
758 trf7970a_send_err_upstream(trf, -EIO);
759 return;
762 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
763 if (ret) {
764 trf7970a_send_err_upstream(trf, ret);
765 return;
768 dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
770 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
772 if (!fifo_bytes)
773 goto no_rx_data;
775 if (fifo_bytes > skb_tailroom(skb)) {
776 skb = skb_copy_expand(skb, skb_headroom(skb),
777 max_t(int, fifo_bytes,
778 TRF7970A_RX_SKB_ALLOC_SIZE),
779 GFP_KERNEL);
780 if (!skb) {
781 trf7970a_send_err_upstream(trf, -ENOMEM);
782 return;
785 kfree_skb(trf->rx_skb);
786 trf->rx_skb = skb;
789 ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
790 skb_put(skb, fifo_bytes), fifo_bytes);
791 if (ret) {
792 trf7970a_send_err_upstream(trf, ret);
793 return;
796 /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
797 if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
798 (trf->special_fcn_reg1 ==
799 TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
800 skb->data[0] >>= 4;
801 status = TRF7970A_IRQ_STATUS_SRX;
802 } else {
803 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
805 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
806 if (ret) {
807 trf7970a_send_err_upstream(trf, ret);
808 return;
811 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
813 /* If there are bytes in the FIFO, set status to '0' so
814 * the if stmt below doesn't fire and the driver will wait
815 * for the trf7970a to generate another RX interrupt.
817 if (fifo_bytes)
818 status = 0;
821 no_rx_data:
822 if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
823 trf7970a_send_upstream(trf);
824 return;
827 dev_dbg(trf->dev, "Setting timeout for %d ms\n",
828 TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
830 schedule_delayed_work(&trf->timeout_work,
831 msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
834 static irqreturn_t trf7970a_irq(int irq, void *dev_id)
836 struct trf7970a *trf = dev_id;
837 int ret;
838 u8 status, fifo_bytes, iso_ctrl;
840 mutex_lock(&trf->lock);
842 if (trf->state == TRF7970A_ST_RF_OFF) {
843 mutex_unlock(&trf->lock);
844 return IRQ_NONE;
847 ret = trf7970a_read_irqstatus(trf, &status);
848 if (ret) {
849 mutex_unlock(&trf->lock);
850 return IRQ_NONE;
853 dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
854 status);
856 if (!status) {
857 mutex_unlock(&trf->lock);
858 return IRQ_NONE;
861 switch (trf->state) {
862 case TRF7970A_ST_IDLE:
863 case TRF7970A_ST_IDLE_RX_BLOCKED:
864 /* If initiator and getting interrupts caused by RF noise,
865 * turn off the receiver to avoid unnecessary interrupts.
866 * It will be turned back on in trf7970a_send_cmd() when
867 * the next command is issued.
869 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
870 trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
871 trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
874 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
875 break;
876 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
877 if (status & TRF7970A_IRQ_STATUS_TX) {
878 trf->ignore_timeout =
879 !cancel_delayed_work(&trf->timeout_work);
880 trf7970a_fill_fifo(trf);
881 } else {
882 trf7970a_send_err_upstream(trf, -EIO);
884 break;
885 case TRF7970A_ST_WAIT_FOR_RX_DATA:
886 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
887 if (status & TRF7970A_IRQ_STATUS_SRX) {
888 trf->ignore_timeout =
889 !cancel_delayed_work(&trf->timeout_work);
890 trf7970a_drain_fifo(trf, status);
891 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
892 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
893 &fifo_bytes);
895 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
897 if (ret)
898 trf7970a_send_err_upstream(trf, ret);
899 else if (!fifo_bytes)
900 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
901 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
902 (!trf->is_initiator &&
903 (status == (TRF7970A_IRQ_STATUS_TX |
904 TRF7970A_IRQ_STATUS_NFC_RF)))) {
905 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
907 if (!trf->timeout) {
908 trf->ignore_timeout = !cancel_delayed_work(
909 &trf->timeout_work);
910 trf->rx_skb = ERR_PTR(0);
911 trf7970a_send_upstream(trf);
912 break;
915 if (trf->is_initiator)
916 break;
918 iso_ctrl = trf->iso_ctrl;
920 switch (trf->framing) {
921 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
922 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
923 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
924 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
925 break;
926 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
927 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
928 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
929 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
930 break;
931 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
932 ret = trf7970a_write(trf,
933 TRF7970A_SPECIAL_FCN_REG1,
934 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
935 if (ret)
936 goto err_unlock_exit;
938 trf->special_fcn_reg1 =
939 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
940 break;
941 default:
942 break;
945 if (iso_ctrl != trf->iso_ctrl) {
946 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
947 iso_ctrl);
948 if (ret)
949 goto err_unlock_exit;
951 trf->iso_ctrl = iso_ctrl;
953 } else {
954 trf7970a_send_err_upstream(trf, -EIO);
956 break;
957 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
958 if (status != TRF7970A_IRQ_STATUS_TX)
959 trf7970a_send_err_upstream(trf, -EIO);
960 break;
961 case TRF7970A_ST_LISTENING:
962 if (status & TRF7970A_IRQ_STATUS_SRX) {
963 trf->ignore_timeout =
964 !cancel_delayed_work(&trf->timeout_work);
965 trf7970a_drain_fifo(trf, status);
966 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
967 trf7970a_send_err_upstream(trf, -EIO);
969 break;
970 case TRF7970A_ST_LISTENING_MD:
971 if (status & TRF7970A_IRQ_STATUS_SRX) {
972 trf->ignore_timeout =
973 !cancel_delayed_work(&trf->timeout_work);
975 ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
976 if (ret) {
977 trf7970a_send_err_upstream(trf, ret);
978 } else {
979 trf->state = TRF7970A_ST_LISTENING;
980 trf7970a_drain_fifo(trf, status);
982 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
983 trf7970a_send_err_upstream(trf, -EIO);
985 break;
986 default:
987 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
988 __func__, trf->state);
991 err_unlock_exit:
992 mutex_unlock(&trf->lock);
993 return IRQ_HANDLED;
996 static void trf7970a_issue_eof(struct trf7970a *trf)
998 int ret;
1000 dev_dbg(trf->dev, "Issuing EOF\n");
1002 ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
1003 if (ret)
1004 trf7970a_send_err_upstream(trf, ret);
1006 ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
1007 if (ret)
1008 trf7970a_send_err_upstream(trf, ret);
1010 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
1012 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
1013 trf->timeout, trf->state);
1015 schedule_delayed_work(&trf->timeout_work,
1016 msecs_to_jiffies(trf->timeout));
1019 static void trf7970a_timeout_work_handler(struct work_struct *work)
1021 struct trf7970a *trf = container_of(work, struct trf7970a,
1022 timeout_work.work);
1024 dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1025 trf->state, trf->ignore_timeout);
1027 mutex_lock(&trf->lock);
1029 if (trf->ignore_timeout)
1030 trf->ignore_timeout = false;
1031 else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1032 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1033 else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1034 trf7970a_issue_eof(trf);
1035 else
1036 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1038 mutex_unlock(&trf->lock);
1041 static int trf7970a_init(struct trf7970a *trf)
1043 int ret;
1045 dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1047 ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1048 if (ret)
1049 goto err_out;
1051 ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1052 if (ret)
1053 goto err_out;
1055 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1056 trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1057 if (ret)
1058 goto err_out;
1060 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1061 if (ret)
1062 goto err_out;
1064 usleep_range(1000, 2000);
1066 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1068 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1069 trf->modulator_sys_clk_ctrl);
1070 if (ret)
1071 goto err_out;
1073 ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1074 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1075 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1076 if (ret)
1077 goto err_out;
1079 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1080 if (ret)
1081 goto err_out;
1083 trf->special_fcn_reg1 = 0;
1085 trf->iso_ctrl = 0xff;
1086 return 0;
1088 err_out:
1089 dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1090 return ret;
1093 static void trf7970a_switch_rf_off(struct trf7970a *trf)
1095 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1096 (trf->state == TRF7970A_ST_RF_OFF))
1097 return;
1099 dev_dbg(trf->dev, "Switching rf off\n");
1101 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1103 trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1105 trf->aborting = false;
1106 trf->state = TRF7970A_ST_RF_OFF;
1108 pm_runtime_mark_last_busy(trf->dev);
1109 pm_runtime_put_autosuspend(trf->dev);
1112 static int trf7970a_switch_rf_on(struct trf7970a *trf)
1114 int ret;
1116 dev_dbg(trf->dev, "Switching rf on\n");
1118 pm_runtime_get_sync(trf->dev);
1120 if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1121 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1122 trf->state);
1123 return -EINVAL;
1126 ret = trf7970a_init(trf);
1127 if (ret) {
1128 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1129 return ret;
1132 trf->state = TRF7970A_ST_IDLE;
1134 return 0;
1137 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1139 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1140 int ret = 0;
1142 dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1144 mutex_lock(&trf->lock);
1146 if (on) {
1147 switch (trf->state) {
1148 case TRF7970A_ST_PWR_OFF:
1149 case TRF7970A_ST_RF_OFF:
1150 ret = trf7970a_switch_rf_on(trf);
1151 break;
1152 case TRF7970A_ST_IDLE:
1153 case TRF7970A_ST_IDLE_RX_BLOCKED:
1154 break;
1155 default:
1156 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1157 __func__, trf->state, on);
1158 trf7970a_switch_rf_off(trf);
1159 ret = -EINVAL;
1161 } else {
1162 switch (trf->state) {
1163 case TRF7970A_ST_PWR_OFF:
1164 case TRF7970A_ST_RF_OFF:
1165 break;
1166 default:
1167 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1168 __func__, trf->state, on);
1169 ret = -EINVAL;
1170 /* FALLTHROUGH */
1171 case TRF7970A_ST_IDLE:
1172 case TRF7970A_ST_IDLE_RX_BLOCKED:
1173 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1174 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1175 trf7970a_switch_rf_off(trf);
1179 mutex_unlock(&trf->lock);
1180 return ret;
1183 static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1185 int ret = 0;
1187 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1189 switch (tech) {
1190 case NFC_DIGITAL_RF_TECH_106A:
1191 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1192 trf->modulator_sys_clk_ctrl =
1193 (trf->modulator_sys_clk_ctrl & 0xf8) |
1194 TRF7970A_MODULATOR_DEPTH_OOK;
1195 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1196 break;
1197 case NFC_DIGITAL_RF_TECH_106B:
1198 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1199 trf->modulator_sys_clk_ctrl =
1200 (trf->modulator_sys_clk_ctrl & 0xf8) |
1201 TRF7970A_MODULATOR_DEPTH_ASK10;
1202 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1203 break;
1204 case NFC_DIGITAL_RF_TECH_212F:
1205 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1206 trf->modulator_sys_clk_ctrl =
1207 (trf->modulator_sys_clk_ctrl & 0xf8) |
1208 TRF7970A_MODULATOR_DEPTH_ASK10;
1209 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1210 break;
1211 case NFC_DIGITAL_RF_TECH_424F:
1212 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1213 trf->modulator_sys_clk_ctrl =
1214 (trf->modulator_sys_clk_ctrl & 0xf8) |
1215 TRF7970A_MODULATOR_DEPTH_ASK10;
1216 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1217 break;
1218 case NFC_DIGITAL_RF_TECH_ISO15693:
1219 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1220 trf->modulator_sys_clk_ctrl =
1221 (trf->modulator_sys_clk_ctrl & 0xf8) |
1222 TRF7970A_MODULATOR_DEPTH_OOK;
1223 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1224 break;
1225 default:
1226 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1227 return -EINVAL;
1230 trf->technology = tech;
1232 /* If in initiator mode and not changing the RF tech due to a
1233 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1234 * trf7970a_init()), clear the NFC Target Detection Level register
1235 * due to erratum.
1237 if (trf->iso_ctrl == 0xff)
1238 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1240 return ret;
1243 static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1245 int ret;
1246 u8 rssi;
1248 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1249 trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
1250 if (ret)
1251 return ret;
1253 ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1254 if (ret)
1255 return ret;
1257 usleep_range(50, 60);
1259 ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1260 if (ret)
1261 return ret;
1263 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1264 trf->chip_status_ctrl);
1265 if (ret)
1266 return ret;
1268 if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1269 *is_rf_field = true;
1270 else
1271 *is_rf_field = false;
1273 return 0;
1276 static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1278 u8 iso_ctrl = trf->iso_ctrl_tech;
1279 bool is_rf_field = false;
1280 int ret;
1282 dev_dbg(trf->dev, "framing: %d\n", framing);
1284 switch (framing) {
1285 case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1286 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1287 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1288 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1289 break;
1290 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1291 case NFC_DIGITAL_FRAMING_NFCA_T4T:
1292 case NFC_DIGITAL_FRAMING_NFCB:
1293 case NFC_DIGITAL_FRAMING_NFCB_T4T:
1294 case NFC_DIGITAL_FRAMING_NFCF:
1295 case NFC_DIGITAL_FRAMING_NFCF_T3T:
1296 case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1297 case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1298 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1299 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1300 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1301 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1302 break;
1303 case NFC_DIGITAL_FRAMING_NFCA_T2T:
1304 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1305 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1306 break;
1307 default:
1308 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1309 return -EINVAL;
1312 trf->framing = framing;
1314 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1315 ret = trf7970a_is_rf_field(trf, &is_rf_field);
1316 if (ret)
1317 return ret;
1319 if (is_rf_field)
1320 return -EBUSY;
1323 if (iso_ctrl != trf->iso_ctrl) {
1324 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1325 if (ret)
1326 return ret;
1328 trf->iso_ctrl = iso_ctrl;
1330 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1331 trf->modulator_sys_clk_ctrl);
1332 if (ret)
1333 return ret;
1336 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1337 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1338 trf->chip_status_ctrl |
1339 TRF7970A_CHIP_STATUS_RF_ON);
1340 if (ret)
1341 return ret;
1343 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1345 usleep_range(trf->guard_time, trf->guard_time + 1000);
1348 return 0;
1351 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1352 int param)
1354 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1355 int ret;
1357 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1359 mutex_lock(&trf->lock);
1361 trf->is_initiator = true;
1363 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1364 (trf->state == TRF7970A_ST_RF_OFF)) {
1365 ret = trf7970a_switch_rf_on(trf);
1366 if (ret)
1367 goto err_unlock;
1370 switch (type) {
1371 case NFC_DIGITAL_CONFIG_RF_TECH:
1372 ret = trf7970a_in_config_rf_tech(trf, param);
1373 break;
1374 case NFC_DIGITAL_CONFIG_FRAMING:
1375 ret = trf7970a_in_config_framing(trf, param);
1376 break;
1377 default:
1378 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1379 ret = -EINVAL;
1382 err_unlock:
1383 mutex_unlock(&trf->lock);
1384 return ret;
1387 static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1389 switch (cmd) {
1390 case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1391 case ISO15693_CMD_LOCK_BLOCK:
1392 case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1393 case ISO15693_CMD_WRITE_AFI:
1394 case ISO15693_CMD_LOCK_AFI:
1395 case ISO15693_CMD_WRITE_DSFID:
1396 case ISO15693_CMD_LOCK_DSFID:
1397 return 1;
1398 break;
1399 default:
1400 return 0;
1404 static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
1406 u8 *req = skb->data;
1407 u8 special_fcn_reg1, iso_ctrl;
1408 int ret;
1410 trf->issue_eof = false;
1412 /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1413 * special functions register 1 is cleared; otherwise, its a write or
1414 * sector select command and '4_bit_RX' must be set.
1416 * When issuing an ISO 15693 command, inspect the flags byte to see
1417 * what speed to use. Also, remember if the OPTION flag is set on
1418 * a Type 5 write or lock command so the driver will know that it
1419 * has to send an EOF in order to get a response.
1421 if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1422 (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1423 if (req[0] == NFC_T2T_CMD_READ)
1424 special_fcn_reg1 = 0;
1425 else
1426 special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1428 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1429 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1430 special_fcn_reg1);
1431 if (ret)
1432 return ret;
1434 trf->special_fcn_reg1 = special_fcn_reg1;
1436 } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1437 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1439 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1440 case 0x00:
1441 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1442 break;
1443 case ISO15693_REQ_FLAG_SUB_CARRIER:
1444 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1445 break;
1446 case ISO15693_REQ_FLAG_DATA_RATE:
1447 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1448 break;
1449 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1450 ISO15693_REQ_FLAG_DATA_RATE):
1451 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1452 break;
1455 if (iso_ctrl != trf->iso_ctrl) {
1456 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1457 if (ret)
1458 return ret;
1460 trf->iso_ctrl = iso_ctrl;
1463 if (trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) {
1464 if (trf7970a_is_iso15693_write_or_lock(req[1]) &&
1465 (req[0] & ISO15693_REQ_FLAG_OPTION))
1466 trf->issue_eof = true;
1467 else if ((trf->quirks &
1468 TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE) &&
1469 (req[1] == ISO15693_CMD_READ_MULTIPLE_BLOCK))
1470 trf->adjust_resp_len = true;
1474 return 0;
1477 static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1478 struct sk_buff *skb, u16 timeout,
1479 nfc_digital_cmd_complete_t cb, void *arg)
1481 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1482 u8 prefix[5];
1483 unsigned int len;
1484 int ret;
1485 u8 status;
1487 dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1488 trf->state, timeout, skb->len);
1490 if (skb->len > TRF7970A_TX_MAX)
1491 return -EINVAL;
1493 mutex_lock(&trf->lock);
1495 if ((trf->state != TRF7970A_ST_IDLE) &&
1496 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1497 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1498 trf->state);
1499 ret = -EIO;
1500 goto out_err;
1503 if (trf->aborting) {
1504 dev_dbg(trf->dev, "Abort process complete\n");
1505 trf->aborting = false;
1506 ret = -ECANCELED;
1507 goto out_err;
1510 if (timeout) {
1511 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1512 GFP_KERNEL);
1513 if (!trf->rx_skb) {
1514 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1515 ret = -ENOMEM;
1516 goto out_err;
1520 if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1521 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1522 if (ret)
1523 goto out_err;
1525 trf->state = TRF7970A_ST_IDLE;
1528 if (trf->is_initiator) {
1529 ret = trf7970a_per_cmd_config(trf, skb);
1530 if (ret)
1531 goto out_err;
1534 trf->ddev = ddev;
1535 trf->tx_skb = skb;
1536 trf->cb = cb;
1537 trf->cb_arg = arg;
1538 trf->timeout = timeout;
1539 trf->ignore_timeout = false;
1541 len = skb->len;
1543 /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1544 * on what the current framing is, the address of the TX length byte 1
1545 * register (0x1d), and the 2 byte length of the data to be transmitted.
1546 * That totals 5 bytes.
1548 prefix[0] = TRF7970A_CMD_BIT_CTRL |
1549 TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1550 prefix[1] = TRF7970A_CMD_BIT_CTRL |
1551 TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1552 prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1554 if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1555 prefix[3] = 0x00;
1556 prefix[4] = 0x0f; /* 7 bits */
1557 } else {
1558 prefix[3] = (len & 0xf00) >> 4;
1559 prefix[3] |= ((len & 0xf0) >> 4);
1560 prefix[4] = ((len & 0x0f) << 4);
1563 len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1565 /* Clear possible spurious interrupt */
1566 ret = trf7970a_read_irqstatus(trf, &status);
1567 if (ret)
1568 goto out_err;
1570 ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1571 if (ret) {
1572 kfree_skb(trf->rx_skb);
1573 trf->rx_skb = NULL;
1576 out_err:
1577 mutex_unlock(&trf->lock);
1578 return ret;
1581 static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1583 int ret = 0;
1585 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1587 switch (tech) {
1588 case NFC_DIGITAL_RF_TECH_106A:
1589 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1590 TRF7970A_ISO_CTRL_NFC_CE |
1591 TRF7970A_ISO_CTRL_NFC_CE_14443A;
1592 trf->modulator_sys_clk_ctrl =
1593 (trf->modulator_sys_clk_ctrl & 0xf8) |
1594 TRF7970A_MODULATOR_DEPTH_OOK;
1595 break;
1596 case NFC_DIGITAL_RF_TECH_212F:
1597 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1598 TRF7970A_ISO_CTRL_NFC_NFCF_212;
1599 trf->modulator_sys_clk_ctrl =
1600 (trf->modulator_sys_clk_ctrl & 0xf8) |
1601 TRF7970A_MODULATOR_DEPTH_ASK10;
1602 break;
1603 case NFC_DIGITAL_RF_TECH_424F:
1604 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1605 TRF7970A_ISO_CTRL_NFC_NFCF_424;
1606 trf->modulator_sys_clk_ctrl =
1607 (trf->modulator_sys_clk_ctrl & 0xf8) |
1608 TRF7970A_MODULATOR_DEPTH_ASK10;
1609 break;
1610 default:
1611 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1612 return -EINVAL;
1615 trf->technology = tech;
1617 /* Normally we write the ISO_CTRL register in
1618 * trf7970a_tg_config_framing() because the framing can change
1619 * the value written. However, when sending a PSL RES,
1620 * digital_tg_send_psl_res_complete() doesn't call
1621 * trf7970a_tg_config_framing() so we must write the register
1622 * here.
1624 if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1625 (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1626 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1627 trf->iso_ctrl_tech);
1629 trf->iso_ctrl = trf->iso_ctrl_tech;
1632 return ret;
1635 /* Since this is a target routine, several of the framing calls are
1636 * made between receiving the request and sending the response so they
1637 * should take effect until after the response is sent. This is accomplished
1638 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1639 * handler.
1641 static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1643 u8 iso_ctrl = trf->iso_ctrl_tech;
1644 int ret;
1646 dev_dbg(trf->dev, "framing: %d\n", framing);
1648 switch (framing) {
1649 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1650 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1651 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1652 break;
1653 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1654 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1655 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1656 /* These ones are applied in the interrupt handler */
1657 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1658 break;
1659 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1660 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1661 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1662 break;
1663 case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1664 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1665 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1666 break;
1667 default:
1668 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1669 return -EINVAL;
1672 trf->framing = framing;
1674 if (iso_ctrl != trf->iso_ctrl) {
1675 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1676 if (ret)
1677 return ret;
1679 trf->iso_ctrl = iso_ctrl;
1681 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1682 trf->modulator_sys_clk_ctrl);
1683 if (ret)
1684 return ret;
1687 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1688 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1689 trf->chip_status_ctrl |
1690 TRF7970A_CHIP_STATUS_RF_ON);
1691 if (ret)
1692 return ret;
1694 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1697 return 0;
1700 static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1701 int param)
1703 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1704 int ret;
1706 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1708 mutex_lock(&trf->lock);
1710 trf->is_initiator = false;
1712 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1713 (trf->state == TRF7970A_ST_RF_OFF)) {
1714 ret = trf7970a_switch_rf_on(trf);
1715 if (ret)
1716 goto err_unlock;
1719 switch (type) {
1720 case NFC_DIGITAL_CONFIG_RF_TECH:
1721 ret = trf7970a_tg_config_rf_tech(trf, param);
1722 break;
1723 case NFC_DIGITAL_CONFIG_FRAMING:
1724 ret = trf7970a_tg_config_framing(trf, param);
1725 break;
1726 default:
1727 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1728 ret = -EINVAL;
1731 err_unlock:
1732 mutex_unlock(&trf->lock);
1733 return ret;
1736 static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1737 nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
1739 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1740 int ret;
1742 mutex_lock(&trf->lock);
1744 if ((trf->state != TRF7970A_ST_IDLE) &&
1745 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1746 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1747 trf->state);
1748 ret = -EIO;
1749 goto out_err;
1752 if (trf->aborting) {
1753 dev_dbg(trf->dev, "Abort process complete\n");
1754 trf->aborting = false;
1755 ret = -ECANCELED;
1756 goto out_err;
1759 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1760 GFP_KERNEL);
1761 if (!trf->rx_skb) {
1762 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1763 ret = -ENOMEM;
1764 goto out_err;
1767 ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1768 TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1769 TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1770 TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1771 TRF7970A_RX_SPECIAL_SETTINGS_C212);
1772 if (ret)
1773 goto out_err;
1775 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1776 trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1777 if (ret)
1778 goto out_err;
1780 ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1781 TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1782 if (ret)
1783 goto out_err;
1785 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1786 TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1787 if (ret)
1788 goto out_err;
1790 trf->ddev = ddev;
1791 trf->cb = cb;
1792 trf->cb_arg = arg;
1793 trf->timeout = timeout;
1794 trf->ignore_timeout = false;
1796 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1797 if (ret)
1798 goto out_err;
1800 trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1801 TRF7970A_ST_LISTENING;
1803 schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1805 out_err:
1806 mutex_unlock(&trf->lock);
1807 return ret;
1810 static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1811 nfc_digital_cmd_complete_t cb, void *arg)
1813 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1815 dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1816 trf->state, timeout);
1818 return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1821 static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1822 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1824 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1825 int ret;
1827 dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1828 trf->state, timeout);
1830 ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1831 NFC_DIGITAL_RF_TECH_106A);
1832 if (ret)
1833 return ret;
1835 ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1836 NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1837 if (ret)
1838 return ret;
1840 return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1843 static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1845 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1847 dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1848 trf->state, trf->md_rf_tech);
1850 *rf_tech = trf->md_rf_tech;
1852 return 0;
1855 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1857 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1859 dev_dbg(trf->dev, "Abort process initiated\n");
1861 mutex_lock(&trf->lock);
1863 switch (trf->state) {
1864 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1865 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1866 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1867 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1868 trf->aborting = true;
1869 break;
1870 case TRF7970A_ST_LISTENING:
1871 trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1872 trf7970a_send_err_upstream(trf, -ECANCELED);
1873 dev_dbg(trf->dev, "Abort process complete\n");
1874 break;
1875 default:
1876 break;
1879 mutex_unlock(&trf->lock);
1882 static struct nfc_digital_ops trf7970a_nfc_ops = {
1883 .in_configure_hw = trf7970a_in_configure_hw,
1884 .in_send_cmd = trf7970a_send_cmd,
1885 .tg_configure_hw = trf7970a_tg_configure_hw,
1886 .tg_send_cmd = trf7970a_send_cmd,
1887 .tg_listen = trf7970a_tg_listen,
1888 .tg_listen_md = trf7970a_tg_listen_md,
1889 .tg_get_rf_tech = trf7970a_tg_get_rf_tech,
1890 .switch_rf = trf7970a_switch_rf,
1891 .abort_cmd = trf7970a_abort_cmd,
1894 static int trf7970a_power_up(struct trf7970a *trf)
1896 int ret;
1898 dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1900 if (trf->state != TRF7970A_ST_PWR_OFF)
1901 return 0;
1903 ret = regulator_enable(trf->regulator);
1904 if (ret) {
1905 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1906 return ret;
1909 usleep_range(5000, 6000);
1911 if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1912 if (gpio_is_valid(trf->en2_gpio)) {
1913 gpio_set_value(trf->en2_gpio, 1);
1914 usleep_range(1000, 2000);
1918 gpio_set_value(trf->en_gpio, 1);
1920 usleep_range(20000, 21000);
1922 trf->state = TRF7970A_ST_RF_OFF;
1924 return 0;
1927 static int trf7970a_power_down(struct trf7970a *trf)
1929 int ret;
1931 dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1933 if (trf->state == TRF7970A_ST_PWR_OFF)
1934 return 0;
1936 if (trf->state != TRF7970A_ST_RF_OFF) {
1937 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1938 trf->state);
1939 return -EBUSY;
1942 gpio_set_value(trf->en_gpio, 0);
1943 if (gpio_is_valid(trf->en2_gpio))
1944 gpio_set_value(trf->en2_gpio, 0);
1946 ret = regulator_disable(trf->regulator);
1947 if (ret)
1948 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1949 ret);
1951 trf->state = TRF7970A_ST_PWR_OFF;
1953 return ret;
1956 static int trf7970a_startup(struct trf7970a *trf)
1958 int ret;
1960 ret = trf7970a_power_up(trf);
1961 if (ret)
1962 return ret;
1964 pm_runtime_set_active(trf->dev);
1965 pm_runtime_enable(trf->dev);
1966 pm_runtime_mark_last_busy(trf->dev);
1968 return 0;
1971 static void trf7970a_shutdown(struct trf7970a *trf)
1973 switch (trf->state) {
1974 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1975 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1976 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1977 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1978 case TRF7970A_ST_LISTENING:
1979 trf7970a_send_err_upstream(trf, -ECANCELED);
1980 /* FALLTHROUGH */
1981 case TRF7970A_ST_IDLE:
1982 case TRF7970A_ST_IDLE_RX_BLOCKED:
1983 trf7970a_switch_rf_off(trf);
1984 break;
1985 default:
1986 break;
1989 pm_runtime_disable(trf->dev);
1990 pm_runtime_set_suspended(trf->dev);
1992 trf7970a_power_down(trf);
1995 static int trf7970a_get_autosuspend_delay(struct device_node *np)
1997 int autosuspend_delay, ret;
1999 ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
2000 if (ret)
2001 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
2003 return autosuspend_delay;
2006 static int trf7970a_get_vin_voltage_override(struct device_node *np,
2007 u32 *vin_uvolts)
2009 return of_property_read_u32(np, "vin-voltage-override", vin_uvolts);
2012 static int trf7970a_probe(struct spi_device *spi)
2014 struct device_node *np = spi->dev.of_node;
2015 struct trf7970a *trf;
2016 int uvolts, autosuspend_delay, ret;
2017 u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
2019 if (!np) {
2020 dev_err(&spi->dev, "No Device Tree entry\n");
2021 return -EINVAL;
2024 trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
2025 if (!trf)
2026 return -ENOMEM;
2028 trf->state = TRF7970A_ST_PWR_OFF;
2029 trf->dev = &spi->dev;
2030 trf->spi = spi;
2032 spi->mode = SPI_MODE_1;
2033 spi->bits_per_word = 8;
2035 ret = spi_setup(spi);
2036 if (ret < 0) {
2037 dev_err(trf->dev, "Can't set up SPI Communication\n");
2038 return ret;
2041 if (of_property_read_bool(np, "t5t-rmb-extra-byte-quirk"))
2042 trf->quirks |= TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE;
2044 if (of_property_read_bool(np, "irq-status-read-quirk"))
2045 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2047 /* There are two enable pins - both must be present */
2048 trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
2049 if (!gpio_is_valid(trf->en_gpio)) {
2050 dev_err(trf->dev, "No EN GPIO property\n");
2051 return trf->en_gpio;
2054 ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
2055 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN");
2056 if (ret) {
2057 dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
2058 return ret;
2061 trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
2062 if (!gpio_is_valid(trf->en2_gpio)) {
2063 dev_info(trf->dev, "No EN2 GPIO property\n");
2064 } else {
2065 ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
2066 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
2067 if (ret) {
2068 dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
2069 return ret;
2073 of_property_read_u32(np, "clock-frequency", &clk_freq);
2074 if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
2075 (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
2076 dev_err(trf->dev,
2077 "clock-frequency (%u Hz) unsupported\n",
2078 clk_freq);
2079 return -EINVAL;
2082 if (of_property_read_bool(np, "en2-rf-quirk"))
2083 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2085 ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2086 trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2087 "trf7970a", trf);
2088 if (ret) {
2089 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2090 return ret;
2093 mutex_init(&trf->lock);
2094 INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2096 trf->regulator = devm_regulator_get(&spi->dev, "vin");
2097 if (IS_ERR(trf->regulator)) {
2098 ret = PTR_ERR(trf->regulator);
2099 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2100 goto err_destroy_lock;
2103 ret = regulator_enable(trf->regulator);
2104 if (ret) {
2105 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2106 goto err_destroy_lock;
2109 ret = trf7970a_get_vin_voltage_override(np, &uvolts);
2110 if (ret)
2111 uvolts = regulator_get_voltage(trf->regulator);
2113 if (uvolts > 4000000)
2114 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2116 trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
2117 if (IS_ERR(trf->regulator)) {
2118 ret = PTR_ERR(trf->regulator);
2119 dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
2120 goto err_destroy_lock;
2123 ret = regulator_enable(trf->regulator);
2124 if (ret) {
2125 dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
2126 goto err_destroy_lock;
2129 if (regulator_get_voltage(trf->regulator) == 1800000) {
2130 trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
2131 dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
2134 trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2135 TRF7970A_SUPPORTED_PROTOCOLS,
2136 NFC_DIGITAL_DRV_CAPS_IN_CRC |
2137 NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
2138 if (!trf->ddev) {
2139 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2140 ret = -ENOMEM;
2141 goto err_disable_regulator;
2144 nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2145 nfc_digital_set_drvdata(trf->ddev, trf);
2146 spi_set_drvdata(spi, trf);
2148 autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2150 pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2151 pm_runtime_use_autosuspend(trf->dev);
2153 ret = trf7970a_startup(trf);
2154 if (ret)
2155 goto err_free_ddev;
2157 ret = nfc_digital_register_device(trf->ddev);
2158 if (ret) {
2159 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2160 ret);
2161 goto err_shutdown;
2164 return 0;
2166 err_shutdown:
2167 trf7970a_shutdown(trf);
2168 err_free_ddev:
2169 nfc_digital_free_device(trf->ddev);
2170 err_disable_regulator:
2171 regulator_disable(trf->regulator);
2172 err_destroy_lock:
2173 mutex_destroy(&trf->lock);
2174 return ret;
2177 static int trf7970a_remove(struct spi_device *spi)
2179 struct trf7970a *trf = spi_get_drvdata(spi);
2181 mutex_lock(&trf->lock);
2183 trf7970a_shutdown(trf);
2185 mutex_unlock(&trf->lock);
2187 nfc_digital_unregister_device(trf->ddev);
2188 nfc_digital_free_device(trf->ddev);
2190 regulator_disable(trf->regulator);
2192 mutex_destroy(&trf->lock);
2194 return 0;
2197 #ifdef CONFIG_PM_SLEEP
2198 static int trf7970a_suspend(struct device *dev)
2200 struct spi_device *spi = to_spi_device(dev);
2201 struct trf7970a *trf = spi_get_drvdata(spi);
2203 dev_dbg(dev, "Suspend\n");
2205 mutex_lock(&trf->lock);
2207 trf7970a_shutdown(trf);
2209 mutex_unlock(&trf->lock);
2211 return 0;
2214 static int trf7970a_resume(struct device *dev)
2216 struct spi_device *spi = to_spi_device(dev);
2217 struct trf7970a *trf = spi_get_drvdata(spi);
2218 int ret;
2220 dev_dbg(dev, "Resume\n");
2222 mutex_lock(&trf->lock);
2224 ret = trf7970a_startup(trf);
2226 mutex_unlock(&trf->lock);
2228 return ret;
2230 #endif
2232 #ifdef CONFIG_PM
2233 static int trf7970a_pm_runtime_suspend(struct device *dev)
2235 struct spi_device *spi = to_spi_device(dev);
2236 struct trf7970a *trf = spi_get_drvdata(spi);
2237 int ret;
2239 dev_dbg(dev, "Runtime suspend\n");
2241 mutex_lock(&trf->lock);
2243 ret = trf7970a_power_down(trf);
2245 mutex_unlock(&trf->lock);
2247 return ret;
2250 static int trf7970a_pm_runtime_resume(struct device *dev)
2252 struct spi_device *spi = to_spi_device(dev);
2253 struct trf7970a *trf = spi_get_drvdata(spi);
2254 int ret;
2256 dev_dbg(dev, "Runtime resume\n");
2258 ret = trf7970a_power_up(trf);
2259 if (!ret)
2260 pm_runtime_mark_last_busy(dev);
2262 return ret;
2264 #endif
2266 static const struct dev_pm_ops trf7970a_pm_ops = {
2267 SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2268 SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2269 trf7970a_pm_runtime_resume, NULL)
2272 static const struct of_device_id trf7970a_of_match[] = {
2273 { .compatible = "ti,trf7970a", },
2274 { /* sentinel */ },
2276 MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2278 static const struct spi_device_id trf7970a_id_table[] = {
2279 { "trf7970a", 0 },
2282 MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2284 static struct spi_driver trf7970a_spi_driver = {
2285 .probe = trf7970a_probe,
2286 .remove = trf7970a_remove,
2287 .id_table = trf7970a_id_table,
2288 .driver = {
2289 .name = "trf7970a",
2290 .of_match_table = of_match_ptr(trf7970a_of_match),
2291 .pm = &trf7970a_pm_ops,
2295 module_spi_driver(trf7970a_spi_driver);
2297 MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2298 MODULE_LICENSE("GPL v2");
2299 MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");