1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * TI TRF7970a RFID/NFC Transceiver Driver
4 *
5 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
6 *
7 * Author: Erick Macias <emacias@ti.com>
8 * Author: Felipe Balbi <balbi@ti.com>
9 * Author: Mark A. Greer <mgreer@animalcreek.com>
10 */
11
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/netdevice.h>
15 #include <linux/interrupt.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/nfc.h>
18 #include <linux/skbuff.h>
19 #include <linux/delay.h>
20 #include <linux/gpio/consumer.h>
21 #include <linux/of.h>
22 #include <linux/spi/spi.h>
23 #include <linux/regulator/consumer.h>
24
25 #include <net/nfc/nfc.h>
26 #include <net/nfc/digital.h>
27
28 /* There are 3 ways the host can communicate with the trf7970a:
29 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
30 * SS mode. The driver only supports the two SPI modes.
31 *
32 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
33 * pins must asserted in that order and with specific delays in between.
34 * The delays used in the driver were provided by TI and have been
35 * confirmed to work with this driver. There is a bug with the current
36 * version of the trf7970a that requires that EN2 remain low no matter
37 * what. If it goes high, it will generate an RF field even when in
38 * passive target mode. TI has indicated that the chip will work okay
39 * when EN2 is left low. The 'en2-rf-quirk' device tree property
40 * indicates that trf7970a currently being used has the erratum and
41 * that EN2 must be kept low.
42 *
43 * Timeouts are implemented using the delayed workqueue kernel facility.
44 * Timeouts are required so things don't hang when there is no response
45 * from the trf7970a (or tag). Using this mechanism creates a race with
46 * interrupts, however. That is, an interrupt and a timeout could occur
47 * closely enough together that one is blocked by the mutex while the other
48 * executes. When the timeout handler executes first and blocks the
49 * interrupt handler, it will eventually set the state to IDLE so the
50 * interrupt handler will check the state and exit with no harm done.
51 * When the interrupt handler executes first and blocks the timeout handler,
52 * the cancel_delayed_work() call will know that it didn't cancel the
53 * work item (i.e., timeout) and will return zero. That return code is
54 * used by the timer handler to indicate that it should ignore the timeout
55 * once its unblocked.
56 *
57 * Aborting an active command isn't as simple as it seems because the only
58 * way to abort a command that's already been sent to the tag is so turn
59 * off power to the tag. If we do that, though, we'd have to go through
60 * the entire anticollision procedure again but the digital layer doesn't
61 * support that. So, if an abort is received before trf7970a_send_cmd()
62 * has sent the command to the tag, it simply returns -ECANCELED. If the
63 * command has already been sent to the tag, then the driver continues
64 * normally and recieves the response data (or error) but just before
65 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
66 * upstream instead. If the command failed, that error will be sent
67 * upstream.
68 *
69 * When recieving data from a tag and the interrupt status register has
70 * only the SRX bit set, it means that all of the data has been received
71 * (once what's in the fifo has been read). However, depending on timing
72 * an interrupt status with only the SRX bit set may not be recived. In
73 * those cases, the timeout mechanism is used to wait 20 ms in case more
74 * data arrives. After 20 ms, it is assumed that all of the data has been
75 * received and the accumulated rx data is sent upstream. The
76 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
77 * (i.e., it indicates that some data has been received but we're not sure
78 * if there is more coming so a timeout in this state means all data has
79 * been received and there isn't an error). The delay is 20 ms since delays
80 * of ~16 ms have been observed during testing.
81 *
82 * When transmitting a frame larger than the FIFO size (127 bytes), the
83 * driver will wait 20 ms for the FIFO to drain past the low-watermark
84 * and generate an interrupt. The low-watermark set to 32 bytes so the
85 * interrupt should fire after 127 - 32 = 95 bytes have been sent. At
86 * the lowest possible bit rate (6.62 kbps for 15693), it will take up
87 * to ~14.35 ms so 20 ms is used for the timeout.
88 *
89 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
90 * Having only 4 bits in the FIFO won't normally generate an interrupt so
91 * driver enables the '4_bit_RX' bit of the Special Functions register 1
92 * to cause an interrupt in that case. Leaving that bit for a read command
93 * messes up the data returned so it is only enabled when the framing is
94 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
95 * Unfortunately, that means that the driver has to peek into tx frames
96 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'. This is done by
97 * the trf7970a_per_cmd_config() routine.
98 *
99 * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
100 * frequencies and whether to use low or high data rates in the flags byte
101 * of the frame. This means that the driver has to peek at all 15693 frames
102 * to determine what speed to set the communication to. In addition, write
103 * and lock commands use the OPTION flag to indicate that an EOF must be
104 * sent to the tag before it will send its response. So the driver has to
105 * examine all frames for that reason too.
106 *
107 * It is unclear how long to wait before sending the EOF. According to the
108 * Note under Table 1-1 in section 1.6 of
109 * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
110 * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
111 * enough so 20 ms is used. So the timer is set to 40 ms - 20 ms to drain
112 * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
113 * ensure the wait is long enough before sending the EOF. This seems to work
114 * reliably.
115 */
116
117 #define TRF7970A_SUPPORTED_PROTOCOLS \
118 (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK | \
119 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
120 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
121
122 #define TRF7970A_AUTOSUSPEND_DELAY 30000 /* 30 seconds */
123 #define TRF7970A_13MHZ_CLOCK_FREQUENCY 13560000
124 #define TRF7970A_27MHZ_CLOCK_FREQUENCY 27120000
125
126 #define TRF7970A_RX_SKB_ALLOC_SIZE 256
127
128 #define TRF7970A_FIFO_SIZE 127
129
130 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
131 #define TRF7970A_TX_MAX (4096 - 1)
132
133 #define TRF7970A_WAIT_FOR_TX_IRQ 20
134 #define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT 20
135 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT 20
136 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF 40
137
138 /* Guard times for various RF technologies (in us) */
139 #define TRF7970A_GUARD_TIME_NFCA 5000
140 #define TRF7970A_GUARD_TIME_NFCB 5000
141 #define TRF7970A_GUARD_TIME_NFCF 20000
142 #define TRF7970A_GUARD_TIME_15693 1000
143
144 /* Quirks */
145 /* Erratum: When reading IRQ Status register on trf7970a, we must issue a
146 * read continuous command for IRQ Status and Collision Position registers.
147 */
148 #define TRF7970A_QUIRK_IRQ_STATUS_READ BIT(0)
149 #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW BIT(1)
150
151 /* Direct commands */
152 #define TRF7970A_CMD_IDLE 0x00
153 #define TRF7970A_CMD_SOFT_INIT 0x03
154 #define TRF7970A_CMD_RF_COLLISION 0x04
155 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_N 0x05
156 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_0 0x06
157 #define TRF7970A_CMD_FIFO_RESET 0x0f
158 #define TRF7970A_CMD_TRANSMIT_NO_CRC 0x10
159 #define TRF7970A_CMD_TRANSMIT 0x11
160 #define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC 0x12
161 #define TRF7970A_CMD_DELAY_TRANSMIT 0x13
162 #define TRF7970A_CMD_EOF 0x14
163 #define TRF7970A_CMD_CLOSE_SLOT 0x15
164 #define TRF7970A_CMD_BLOCK_RX 0x16
165 #define TRF7970A_CMD_ENABLE_RX 0x17
166 #define TRF7970A_CMD_TEST_INT_RF 0x18
167 #define TRF7970A_CMD_TEST_EXT_RF 0x19
168 #define TRF7970A_CMD_RX_GAIN_ADJUST 0x1a
169
170 /* Bits determining whether its a direct command or register R/W,
171 * whether to use a continuous SPI transaction or not, and the actual
172 * direct cmd opcode or register address.
173 */
174 #define TRF7970A_CMD_BIT_CTRL BIT(7)
175 #define TRF7970A_CMD_BIT_RW BIT(6)
176 #define TRF7970A_CMD_BIT_CONTINUOUS BIT(5)
177 #define TRF7970A_CMD_BIT_OPCODE(opcode) ((opcode) & 0x1f)
178
179 /* Registers addresses */
180 #define TRF7970A_CHIP_STATUS_CTRL 0x00
181 #define TRF7970A_ISO_CTRL 0x01
182 #define TRF7970A_ISO14443B_TX_OPTIONS 0x02
183 #define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
184 #define TRF7970A_TX_TIMER_SETTING_H_BYTE 0x04
185 #define TRF7970A_TX_TIMER_SETTING_L_BYTE 0x05
186 #define TRF7970A_TX_PULSE_LENGTH_CTRL 0x06
187 #define TRF7970A_RX_NO_RESPONSE_WAIT 0x07
188 #define TRF7970A_RX_WAIT_TIME 0x08
189 #define TRF7970A_MODULATOR_SYS_CLK_CTRL 0x09
190 #define TRF7970A_RX_SPECIAL_SETTINGS 0x0a
191 #define TRF7970A_REG_IO_CTRL 0x0b
192 #define TRF7970A_IRQ_STATUS 0x0c
193 #define TRF7970A_COLLISION_IRQ_MASK 0x0d
194 #define TRF7970A_COLLISION_POSITION 0x0e
195 #define TRF7970A_RSSI_OSC_STATUS 0x0f
196 #define TRF7970A_SPECIAL_FCN_REG1 0x10
197 #define TRF7970A_SPECIAL_FCN_REG2 0x11
198 #define TRF7970A_RAM1 0x12
199 #define TRF7970A_RAM2 0x13
200 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS 0x14
201 #define TRF7970A_NFC_LOW_FIELD_LEVEL 0x16
202 #define TRF7970A_NFCID1 0x17
203 #define TRF7970A_NFC_TARGET_LEVEL 0x18
204 #define TRF79070A_NFC_TARGET_PROTOCOL 0x19
205 #define TRF7970A_TEST_REGISTER1 0x1a
206 #define TRF7970A_TEST_REGISTER2 0x1b
207 #define TRF7970A_FIFO_STATUS 0x1c
208 #define TRF7970A_TX_LENGTH_BYTE1 0x1d
209 #define TRF7970A_TX_LENGTH_BYTE2 0x1e
210 #define TRF7970A_FIFO_IO_REGISTER 0x1f
211
212 /* Chip Status Control Register Bits */
213 #define TRF7970A_CHIP_STATUS_VRS5_3 BIT(0)
214 #define TRF7970A_CHIP_STATUS_REC_ON BIT(1)
215 #define TRF7970A_CHIP_STATUS_AGC_ON BIT(2)
216 #define TRF7970A_CHIP_STATUS_PM_ON BIT(3)
217 #define TRF7970A_CHIP_STATUS_RF_PWR BIT(4)
218 #define TRF7970A_CHIP_STATUS_RF_ON BIT(5)
219 #define TRF7970A_CHIP_STATUS_DIRECT BIT(6)
220 #define TRF7970A_CHIP_STATUS_STBY BIT(7)
221
222 /* ISO Control Register Bits */
223 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662 0x00
224 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662 0x01
225 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648 0x02
226 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
227 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a 0x04
228 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667 0x05
229 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669 0x06
230 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
231 #define TRF7970A_ISO_CTRL_14443A_106 0x08
232 #define TRF7970A_ISO_CTRL_14443A_212 0x09
233 #define TRF7970A_ISO_CTRL_14443A_424 0x0a
234 #define TRF7970A_ISO_CTRL_14443A_848 0x0b
235 #define TRF7970A_ISO_CTRL_14443B_106 0x0c
236 #define TRF7970A_ISO_CTRL_14443B_212 0x0d
237 #define TRF7970A_ISO_CTRL_14443B_424 0x0e
238 #define TRF7970A_ISO_CTRL_14443B_848 0x0f
239 #define TRF7970A_ISO_CTRL_FELICA_212 0x1a
240 #define TRF7970A_ISO_CTRL_FELICA_424 0x1b
241 #define TRF7970A_ISO_CTRL_NFC_NFCA_106 0x01
242 #define TRF7970A_ISO_CTRL_NFC_NFCF_212 0x02
243 #define TRF7970A_ISO_CTRL_NFC_NFCF_424 0x03
244 #define TRF7970A_ISO_CTRL_NFC_CE_14443A 0x00
245 #define TRF7970A_ISO_CTRL_NFC_CE_14443B 0x01
246 #define TRF7970A_ISO_CTRL_NFC_CE BIT(2)
247 #define TRF7970A_ISO_CTRL_NFC_ACTIVE BIT(3)
248 #define TRF7970A_ISO_CTRL_NFC_INITIATOR BIT(4)
249 #define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE BIT(5)
250 #define TRF7970A_ISO_CTRL_RFID BIT(5)
251 #define TRF7970A_ISO_CTRL_DIR_MODE BIT(6)
252 #define TRF7970A_ISO_CTRL_RX_CRC_N BIT(7) /* true == No CRC */
253
254 #define TRF7970A_ISO_CTRL_RFID_SPEED_MASK 0x1f
255
256 /* Modulator and SYS_CLK Control Register Bits */
257 #define TRF7970A_MODULATOR_DEPTH(n) ((n) & 0x7)
258 #define TRF7970A_MODULATOR_DEPTH_ASK10 (TRF7970A_MODULATOR_DEPTH(0))
259 #define TRF7970A_MODULATOR_DEPTH_OOK (TRF7970A_MODULATOR_DEPTH(1))
260 #define TRF7970A_MODULATOR_DEPTH_ASK7 (TRF7970A_MODULATOR_DEPTH(2))
261 #define TRF7970A_MODULATOR_DEPTH_ASK8_5 (TRF7970A_MODULATOR_DEPTH(3))
262 #define TRF7970A_MODULATOR_DEPTH_ASK13 (TRF7970A_MODULATOR_DEPTH(4))
263 #define TRF7970A_MODULATOR_DEPTH_ASK16 (TRF7970A_MODULATOR_DEPTH(5))
264 #define TRF7970A_MODULATOR_DEPTH_ASK22 (TRF7970A_MODULATOR_DEPTH(6))
265 #define TRF7970A_MODULATOR_DEPTH_ASK30 (TRF7970A_MODULATOR_DEPTH(7))
266 #define TRF7970A_MODULATOR_EN_ANA BIT(3)
267 #define TRF7970A_MODULATOR_CLK(n) (((n) & 0x3) << 4)
268 #define TRF7970A_MODULATOR_CLK_DISABLED (TRF7970A_MODULATOR_CLK(0))
269 #define TRF7970A_MODULATOR_CLK_3_6 (TRF7970A_MODULATOR_CLK(1))
270 #define TRF7970A_MODULATOR_CLK_6_13 (TRF7970A_MODULATOR_CLK(2))
271 #define TRF7970A_MODULATOR_CLK_13_27 (TRF7970A_MODULATOR_CLK(3))
272 #define TRF7970A_MODULATOR_EN_OOK BIT(6)
273 #define TRF7970A_MODULATOR_27MHZ BIT(7)
274
275 #define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM BIT(0)
276 #define TRF7970A_RX_SPECIAL_SETTINGS_AGCR BIT(1)
277 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB (0x0 << 2)
278 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB (0x1 << 2)
279 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB (0x2 << 2)
280 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB (0x3 << 2)
281 #define TRF7970A_RX_SPECIAL_SETTINGS_HBT BIT(4)
282 #define TRF7970A_RX_SPECIAL_SETTINGS_M848 BIT(5)
283 #define TRF7970A_RX_SPECIAL_SETTINGS_C424 BIT(6)
284 #define TRF7970A_RX_SPECIAL_SETTINGS_C212 BIT(7)
285
286 #define TRF7970A_REG_IO_CTRL_VRS(v) ((v) & 0x07)
287 #define TRF7970A_REG_IO_CTRL_IO_LOW BIT(5)
288 #define TRF7970A_REG_IO_CTRL_EN_EXT_PA BIT(6)
289 #define TRF7970A_REG_IO_CTRL_AUTO_REG BIT(7)
290
291 /* IRQ Status Register Bits */
292 #define TRF7970A_IRQ_STATUS_NORESP BIT(0) /* ISO15693 only */
293 #define TRF7970A_IRQ_STATUS_NFC_COL_ERROR BIT(0)
294 #define TRF7970A_IRQ_STATUS_COL BIT(1)
295 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR BIT(2)
296 #define TRF7970A_IRQ_STATUS_NFC_RF BIT(2)
297 #define TRF7970A_IRQ_STATUS_PARITY_ERROR BIT(3)
298 #define TRF7970A_IRQ_STATUS_NFC_SDD BIT(3)
299 #define TRF7970A_IRQ_STATUS_CRC_ERROR BIT(4)
300 #define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR BIT(4)
301 #define TRF7970A_IRQ_STATUS_FIFO BIT(5)
302 #define TRF7970A_IRQ_STATUS_SRX BIT(6)
303 #define TRF7970A_IRQ_STATUS_TX BIT(7)
304
305 #define TRF7970A_IRQ_STATUS_ERROR \
306 (TRF7970A_IRQ_STATUS_COL | \
307 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR | \
308 TRF7970A_IRQ_STATUS_PARITY_ERROR | \
309 TRF7970A_IRQ_STATUS_CRC_ERROR)
310
311 #define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK (BIT(2) | BIT(1) | BIT(0))
312 #define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK (BIT(5) | BIT(4) | BIT(3))
313 #define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK BIT(6)
314
315 #define TRF7970A_SPECIAL_FCN_REG1_COL_7_6 BIT(0)
316 #define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL BIT(1)
317 #define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX BIT(2)
318 #define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE BIT(3)
319 #define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US BIT(4)
320 #define TRF7970A_SPECIAL_FCN_REG1_PAR43 BIT(5)
321
322 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124 (0x0 << 2)
323 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120 (0x1 << 2)
324 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112 (0x2 << 2)
325 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 (0x3 << 2)
326 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4 0x0
327 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8 0x1
328 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16 0x2
329 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32 0x3
330
331 #define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v) ((v) & 0x07)
332 #define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS BIT(7)
333
334 #define TRF7970A_NFC_TARGET_LEVEL_RFDET(v) ((v) & 0x07)
335 #define TRF7970A_NFC_TARGET_LEVEL_HI_RF BIT(3)
336 #define TRF7970A_NFC_TARGET_LEVEL_SDD_EN BIT(5)
337 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES (0x0 << 6)
338 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES (0x1 << 6)
339 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES (0x2 << 6)
340
341 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106 BIT(0)
342 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212 BIT(1)
343 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424 (BIT(0) | BIT(1))
344 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B BIT(2)
345 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 BIT(3)
346 #define TRF79070A_NFC_TARGET_PROTOCOL_FELICA BIT(4)
347 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_L BIT(6)
348 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_H BIT(7)
349
350 #define TRF79070A_NFC_TARGET_PROTOCOL_106A \
351 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
352 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
353 TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 | \
354 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
355
356 #define TRF79070A_NFC_TARGET_PROTOCOL_106B \
357 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
358 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
359 TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B | \
360 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
361
362 #define TRF79070A_NFC_TARGET_PROTOCOL_212F \
363 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H | \
364 TRF79070A_NFC_TARGET_PROTOCOL_RF_L | \
365 TRF79070A_NFC_TARGET_PROTOCOL_FELICA | \
366 TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
367
368 #define TRF79070A_NFC_TARGET_PROTOCOL_424F \
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_424)
373
374 #define TRF7970A_FIFO_STATUS_OVERFLOW BIT(7)
375
376 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
377 #define NFC_T2T_CMD_READ 0x30
378
379 /* ISO 15693 commands codes */
380 #define ISO15693_CMD_INVENTORY 0x01
381 #define ISO15693_CMD_READ_SINGLE_BLOCK 0x20
382 #define ISO15693_CMD_WRITE_SINGLE_BLOCK 0x21
383 #define ISO15693_CMD_LOCK_BLOCK 0x22
384 #define ISO15693_CMD_READ_MULTIPLE_BLOCK 0x23
385 #define ISO15693_CMD_WRITE_MULTIPLE_BLOCK 0x24
386 #define ISO15693_CMD_SELECT 0x25
387 #define ISO15693_CMD_RESET_TO_READY 0x26
388 #define ISO15693_CMD_WRITE_AFI 0x27
389 #define ISO15693_CMD_LOCK_AFI 0x28
390 #define ISO15693_CMD_WRITE_DSFID 0x29
391 #define ISO15693_CMD_LOCK_DSFID 0x2a
392 #define ISO15693_CMD_GET_SYSTEM_INFO 0x2b
393 #define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS 0x2c
394
395 /* ISO 15693 request and response flags */
396 #define ISO15693_REQ_FLAG_SUB_CARRIER BIT(0)
397 #define ISO15693_REQ_FLAG_DATA_RATE BIT(1)
398 #define ISO15693_REQ_FLAG_INVENTORY BIT(2)
399 #define ISO15693_REQ_FLAG_PROTOCOL_EXT BIT(3)
400 #define ISO15693_REQ_FLAG_SELECT BIT(4)
401 #define ISO15693_REQ_FLAG_AFI BIT(4)
402 #define ISO15693_REQ_FLAG_ADDRESS BIT(5)
403 #define ISO15693_REQ_FLAG_NB_SLOTS BIT(5)
404 #define ISO15693_REQ_FLAG_OPTION BIT(6)
405
406 #define ISO15693_REQ_FLAG_SPEED_MASK \
407 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
408
409 enum trf7970a_state {
410 TRF7970A_ST_PWR_OFF,
411 TRF7970A_ST_RF_OFF,
412 TRF7970A_ST_IDLE,
413 TRF7970A_ST_IDLE_RX_BLOCKED,
414 TRF7970A_ST_WAIT_FOR_TX_FIFO,
415 TRF7970A_ST_WAIT_FOR_RX_DATA,
416 TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
417 TRF7970A_ST_WAIT_TO_ISSUE_EOF,
418 TRF7970A_ST_LISTENING,
419 TRF7970A_ST_LISTENING_MD,
420 TRF7970A_ST_MAX
421 };
422
423 struct trf7970a {
424 enum trf7970a_state state;
425 struct device *dev;
426 struct spi_device *spi;
427 struct regulator *regulator;
428 struct nfc_digital_dev *ddev;
429 u32 quirks;
430 bool is_initiator;
431 bool aborting;
432 struct sk_buff *tx_skb;
433 struct sk_buff *rx_skb;
434 nfc_digital_cmd_complete_t cb;
435 void *cb_arg;
436 u8 chip_status_ctrl;
437 u8 iso_ctrl;
438 u8 iso_ctrl_tech;
439 u8 modulator_sys_clk_ctrl;
440 u8 special_fcn_reg1;
441 u8 io_ctrl;
442 unsigned int guard_time;
443 int technology;
444 int framing;
445 u8 md_rf_tech;
446 u8 tx_cmd;
447 bool issue_eof;
448 struct gpio_desc *en_gpiod;
449 struct gpio_desc *en2_gpiod;
450 struct mutex lock;
451 unsigned int timeout;
452 bool ignore_timeout;
453 struct delayed_work timeout_work;
454 };
455
trf7970a_cmd(struct trf7970a * trf,u8 opcode)456 static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
457 {
458 u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
459 int ret;
460
461 dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
462
463 ret = spi_write(trf->spi, &cmd, 1);
464 if (ret)
465 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
466 ret);
467 return ret;
468 }
469
trf7970a_read(struct trf7970a * trf,u8 reg,u8 * val)470 static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
471 {
472 u8 addr = TRF7970A_CMD_BIT_RW | reg;
473 int ret;
474
475 ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
476 if (ret)
477 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
478 ret);
479
480 dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
481
482 return ret;
483 }
484
trf7970a_read_cont(struct trf7970a * trf,u8 reg,u8 * buf,size_t len)485 static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf,
486 size_t len)
487 {
488 u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
489 struct spi_transfer t[2];
490 struct spi_message m;
491 int ret;
492
493 dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
494
495 spi_message_init(&m);
496
497 memset(&t, 0, sizeof(t));
498
499 t[0].tx_buf = &addr;
500 t[0].len = sizeof(addr);
501 spi_message_add_tail(&t[0], &m);
502
503 t[1].rx_buf = buf;
504 t[1].len = len;
505 spi_message_add_tail(&t[1], &m);
506
507 ret = spi_sync(trf->spi, &m);
508 if (ret)
509 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
510 ret);
511 return ret;
512 }
513
trf7970a_write(struct trf7970a * trf,u8 reg,u8 val)514 static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
515 {
516 u8 buf[2] = { reg, val };
517 int ret;
518
519 dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
520
521 ret = spi_write(trf->spi, buf, 2);
522 if (ret)
523 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
524 buf[0], buf[1], ret);
525
526 return ret;
527 }
528
trf7970a_read_irqstatus(struct trf7970a * trf,u8 * status)529 static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
530 {
531 int ret;
532 u8 buf[2];
533 u8 addr;
534
535 addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
536
537 if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
538 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
539 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
540 } else {
541 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
542 }
543
544 if (ret)
545 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
546 __func__, ret);
547 else
548 *status = buf[0];
549
550 return ret;
551 }
552
trf7970a_read_target_proto(struct trf7970a * trf,u8 * target_proto)553 static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
554 {
555 int ret;
556 u8 buf[2];
557 u8 addr;
558
559 addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
560 TRF7970A_CMD_BIT_CONTINUOUS;
561
562 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
563 if (ret)
564 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
565 __func__, ret);
566 else
567 *target_proto = buf[0];
568
569 return ret;
570 }
571
trf7970a_mode_detect(struct trf7970a * trf,u8 * rf_tech)572 static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
573 {
574 int ret;
575 u8 target_proto, tech;
576
577 ret = trf7970a_read_target_proto(trf, &target_proto);
578 if (ret)
579 return ret;
580
581 switch (target_proto) {
582 case TRF79070A_NFC_TARGET_PROTOCOL_106A:
583 tech = NFC_DIGITAL_RF_TECH_106A;
584 break;
585 case TRF79070A_NFC_TARGET_PROTOCOL_106B:
586 tech = NFC_DIGITAL_RF_TECH_106B;
587 break;
588 case TRF79070A_NFC_TARGET_PROTOCOL_212F:
589 tech = NFC_DIGITAL_RF_TECH_212F;
590 break;
591 case TRF79070A_NFC_TARGET_PROTOCOL_424F:
592 tech = NFC_DIGITAL_RF_TECH_424F;
593 break;
594 default:
595 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
596 __func__, target_proto);
597 return -EIO;
598 }
599
600 *rf_tech = tech;
601
602 return ret;
603 }
604
trf7970a_send_upstream(struct trf7970a * trf)605 static void trf7970a_send_upstream(struct trf7970a *trf)
606 {
607 dev_kfree_skb_any(trf->tx_skb);
608 trf->tx_skb = NULL;
609
610 if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
611 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
612 16, 1, trf->rx_skb->data, trf->rx_skb->len,
613 false);
614
615 trf->state = TRF7970A_ST_IDLE;
616
617 if (trf->aborting) {
618 dev_dbg(trf->dev, "Abort process complete\n");
619
620 if (!IS_ERR(trf->rx_skb)) {
621 kfree_skb(trf->rx_skb);
622 trf->rx_skb = ERR_PTR(-ECANCELED);
623 }
624
625 trf->aborting = false;
626 }
627
628 trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
629
630 trf->rx_skb = NULL;
631 }
632
trf7970a_send_err_upstream(struct trf7970a * trf,int errno)633 static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
634 {
635 dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
636
637 cancel_delayed_work(&trf->timeout_work);
638
639 kfree_skb(trf->rx_skb);
640 trf->rx_skb = ERR_PTR(errno);
641
642 trf7970a_send_upstream(trf);
643 }
644
trf7970a_transmit(struct trf7970a * trf,struct sk_buff * skb,unsigned int len,const u8 * prefix,unsigned int prefix_len)645 static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
646 unsigned int len, const u8 *prefix,
647 unsigned int prefix_len)
648 {
649 struct spi_transfer t[2];
650 struct spi_message m;
651 unsigned int timeout;
652 int ret;
653
654 print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
655 16, 1, skb->data, len, false);
656
657 spi_message_init(&m);
658
659 memset(&t, 0, sizeof(t));
660
661 t[0].tx_buf = prefix;
662 t[0].len = prefix_len;
663 spi_message_add_tail(&t[0], &m);
664
665 t[1].tx_buf = skb->data;
666 t[1].len = len;
667 spi_message_add_tail(&t[1], &m);
668
669 ret = spi_sync(trf->spi, &m);
670 if (ret) {
671 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
672 ret);
673 return ret;
674 }
675
676 skb_pull(skb, len);
677
678 if (skb->len > 0) {
679 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
680 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
681 } else {
682 if (trf->issue_eof) {
683 trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
684 timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
685 } else {
686 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
687
688 if (!trf->timeout)
689 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
690 else
691 timeout = trf->timeout;
692 }
693 }
694
695 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
696 trf->state);
697
698 schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
699
700 return 0;
701 }
702
trf7970a_fill_fifo(struct trf7970a * trf)703 static void trf7970a_fill_fifo(struct trf7970a *trf)
704 {
705 struct sk_buff *skb = trf->tx_skb;
706 unsigned int len;
707 int ret;
708 u8 fifo_bytes;
709 u8 prefix;
710
711 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
712 if (ret) {
713 trf7970a_send_err_upstream(trf, ret);
714 return;
715 }
716
717 dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
718
719 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
720
721 /* Calculate how much more data can be written to the fifo */
722 len = TRF7970A_FIFO_SIZE - fifo_bytes;
723 if (!len) {
724 schedule_delayed_work(&trf->timeout_work,
725 msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
726 return;
727 }
728
729 len = min(skb->len, len);
730
731 prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
732
733 ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
734 if (ret)
735 trf7970a_send_err_upstream(trf, ret);
736 }
737
trf7970a_drain_fifo(struct trf7970a * trf,u8 status)738 static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
739 {
740 struct sk_buff *skb = trf->rx_skb;
741 int ret;
742 u8 fifo_bytes;
743
744 if (status & TRF7970A_IRQ_STATUS_ERROR) {
745 trf7970a_send_err_upstream(trf, -EIO);
746 return;
747 }
748
749 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
750 if (ret) {
751 trf7970a_send_err_upstream(trf, ret);
752 return;
753 }
754
755 dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
756
757 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
758
759 if (!fifo_bytes)
760 goto no_rx_data;
761
762 if (fifo_bytes > skb_tailroom(skb)) {
763 skb = skb_copy_expand(skb, skb_headroom(skb),
764 max_t(int, fifo_bytes,
765 TRF7970A_RX_SKB_ALLOC_SIZE),
766 GFP_KERNEL);
767 if (!skb) {
768 trf7970a_send_err_upstream(trf, -ENOMEM);
769 return;
770 }
771
772 kfree_skb(trf->rx_skb);
773 trf->rx_skb = skb;
774 }
775
776 ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
777 skb_put(skb, fifo_bytes), fifo_bytes);
778 if (ret) {
779 trf7970a_send_err_upstream(trf, ret);
780 return;
781 }
782
783 /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
784 if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
785 (trf->special_fcn_reg1 == TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
786 skb->data[0] >>= 4;
787 status = TRF7970A_IRQ_STATUS_SRX;
788 } else {
789 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
790
791 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
792 if (ret) {
793 trf7970a_send_err_upstream(trf, ret);
794 return;
795 }
796
797 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
798
799 /* If there are bytes in the FIFO, set status to '0' so
800 * the if stmt below doesn't fire and the driver will wait
801 * for the trf7970a to generate another RX interrupt.
802 */
803 if (fifo_bytes)
804 status = 0;
805 }
806
807 no_rx_data:
808 if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
809 trf7970a_send_upstream(trf);
810 return;
811 }
812
813 dev_dbg(trf->dev, "Setting timeout for %d ms\n",
814 TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
815
816 schedule_delayed_work(&trf->timeout_work,
817 msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
818 }
819
trf7970a_irq(int irq,void * dev_id)820 static irqreturn_t trf7970a_irq(int irq, void *dev_id)
821 {
822 struct trf7970a *trf = dev_id;
823 int ret;
824 u8 status, fifo_bytes, iso_ctrl;
825
826 mutex_lock(&trf->lock);
827
828 if (trf->state == TRF7970A_ST_RF_OFF) {
829 mutex_unlock(&trf->lock);
830 return IRQ_NONE;
831 }
832
833 ret = trf7970a_read_irqstatus(trf, &status);
834 if (ret) {
835 mutex_unlock(&trf->lock);
836 return IRQ_NONE;
837 }
838
839 dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
840 status);
841
842 if (!status) {
843 mutex_unlock(&trf->lock);
844 return IRQ_NONE;
845 }
846
847 switch (trf->state) {
848 case TRF7970A_ST_IDLE:
849 case TRF7970A_ST_IDLE_RX_BLOCKED:
850 /* If initiator and getting interrupts caused by RF noise,
851 * turn off the receiver to avoid unnecessary interrupts.
852 * It will be turned back on in trf7970a_send_cmd() when
853 * the next command is issued.
854 */
855 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
856 trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
857 trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
858 }
859
860 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
861 break;
862 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
863 if (status & TRF7970A_IRQ_STATUS_TX) {
864 trf->ignore_timeout =
865 !cancel_delayed_work(&trf->timeout_work);
866 trf7970a_fill_fifo(trf);
867 } else {
868 trf7970a_send_err_upstream(trf, -EIO);
869 }
870 break;
871 case TRF7970A_ST_WAIT_FOR_RX_DATA:
872 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
873 if (status & TRF7970A_IRQ_STATUS_SRX) {
874 trf->ignore_timeout =
875 !cancel_delayed_work(&trf->timeout_work);
876 trf7970a_drain_fifo(trf, status);
877 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
878 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
879 &fifo_bytes);
880
881 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
882
883 if (ret)
884 trf7970a_send_err_upstream(trf, ret);
885 else if (!fifo_bytes)
886 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
887 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
888 (!trf->is_initiator &&
889 (status == (TRF7970A_IRQ_STATUS_TX |
890 TRF7970A_IRQ_STATUS_NFC_RF)))) {
891 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
892
893 if (!trf->timeout) {
894 trf->ignore_timeout =
895 !cancel_delayed_work(&trf->timeout_work);
896 trf->rx_skb = ERR_PTR(0);
897 trf7970a_send_upstream(trf);
898 break;
899 }
900
901 if (trf->is_initiator)
902 break;
903
904 iso_ctrl = trf->iso_ctrl;
905
906 switch (trf->framing) {
907 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
908 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
909 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
910 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
911 break;
912 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
913 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
914 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
915 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
916 break;
917 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
918 ret = trf7970a_write(trf,
919 TRF7970A_SPECIAL_FCN_REG1,
920 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
921 if (ret)
922 goto err_unlock_exit;
923
924 trf->special_fcn_reg1 =
925 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
926 break;
927 default:
928 break;
929 }
930
931 if (iso_ctrl != trf->iso_ctrl) {
932 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
933 iso_ctrl);
934 if (ret)
935 goto err_unlock_exit;
936
937 trf->iso_ctrl = iso_ctrl;
938 }
939 } else {
940 trf7970a_send_err_upstream(trf, -EIO);
941 }
942 break;
943 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
944 if (status != TRF7970A_IRQ_STATUS_TX)
945 trf7970a_send_err_upstream(trf, -EIO);
946 break;
947 case TRF7970A_ST_LISTENING:
948 if (status & TRF7970A_IRQ_STATUS_SRX) {
949 trf->ignore_timeout =
950 !cancel_delayed_work(&trf->timeout_work);
951 trf7970a_drain_fifo(trf, status);
952 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
953 trf7970a_send_err_upstream(trf, -EIO);
954 }
955 break;
956 case TRF7970A_ST_LISTENING_MD:
957 if (status & TRF7970A_IRQ_STATUS_SRX) {
958 trf->ignore_timeout =
959 !cancel_delayed_work(&trf->timeout_work);
960
961 ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
962 if (ret) {
963 trf7970a_send_err_upstream(trf, ret);
964 } else {
965 trf->state = TRF7970A_ST_LISTENING;
966 trf7970a_drain_fifo(trf, status);
967 }
968 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
969 trf7970a_send_err_upstream(trf, -EIO);
970 }
971 break;
972 default:
973 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
974 __func__, trf->state);
975 }
976
977 err_unlock_exit:
978 mutex_unlock(&trf->lock);
979 return IRQ_HANDLED;
980 }
981
trf7970a_issue_eof(struct trf7970a * trf)982 static void trf7970a_issue_eof(struct trf7970a *trf)
983 {
984 int ret;
985
986 dev_dbg(trf->dev, "Issuing EOF\n");
987
988 ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
989 if (ret)
990 trf7970a_send_err_upstream(trf, ret);
991
992 ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
993 if (ret)
994 trf7970a_send_err_upstream(trf, ret);
995
996 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
997
998 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
999 trf->timeout, trf->state);
1000
1001 schedule_delayed_work(&trf->timeout_work,
1002 msecs_to_jiffies(trf->timeout));
1003 }
1004
trf7970a_timeout_work_handler(struct work_struct * work)1005 static void trf7970a_timeout_work_handler(struct work_struct *work)
1006 {
1007 struct trf7970a *trf = container_of(work, struct trf7970a,
1008 timeout_work.work);
1009
1010 dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1011 trf->state, trf->ignore_timeout);
1012
1013 mutex_lock(&trf->lock);
1014
1015 if (trf->ignore_timeout)
1016 trf->ignore_timeout = false;
1017 else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1018 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1019 else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1020 trf7970a_issue_eof(trf);
1021 else
1022 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1023
1024 mutex_unlock(&trf->lock);
1025 }
1026
trf7970a_init(struct trf7970a * trf)1027 static int trf7970a_init(struct trf7970a *trf)
1028 {
1029 int ret;
1030
1031 dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1032
1033 ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1034 if (ret)
1035 goto err_out;
1036
1037 ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1038 if (ret)
1039 goto err_out;
1040
1041 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1042 trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1043 if (ret)
1044 goto err_out;
1045
1046 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1047 if (ret)
1048 goto err_out;
1049
1050 usleep_range(1000, 2000);
1051
1052 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1053
1054 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1055 trf->modulator_sys_clk_ctrl);
1056 if (ret)
1057 goto err_out;
1058
1059 ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1060 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1061 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1062 if (ret)
1063 goto err_out;
1064
1065 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1066 if (ret)
1067 goto err_out;
1068
1069 trf->special_fcn_reg1 = 0;
1070
1071 trf->iso_ctrl = 0xff;
1072 return 0;
1073
1074 err_out:
1075 dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1076 return ret;
1077 }
1078
trf7970a_switch_rf_off(struct trf7970a * trf)1079 static void trf7970a_switch_rf_off(struct trf7970a *trf)
1080 {
1081 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1082 (trf->state == TRF7970A_ST_RF_OFF))
1083 return;
1084
1085 dev_dbg(trf->dev, "Switching rf off\n");
1086
1087 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1088
1089 trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1090
1091 trf->aborting = false;
1092 trf->state = TRF7970A_ST_RF_OFF;
1093
1094 pm_runtime_mark_last_busy(trf->dev);
1095 pm_runtime_put_autosuspend(trf->dev);
1096 }
1097
trf7970a_switch_rf_on(struct trf7970a * trf)1098 static int trf7970a_switch_rf_on(struct trf7970a *trf)
1099 {
1100 int ret;
1101
1102 dev_dbg(trf->dev, "Switching rf on\n");
1103
1104 pm_runtime_get_sync(trf->dev);
1105
1106 if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1107 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1108 trf->state);
1109 return -EINVAL;
1110 }
1111
1112 ret = trf7970a_init(trf);
1113 if (ret) {
1114 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1115 return ret;
1116 }
1117
1118 trf->state = TRF7970A_ST_IDLE;
1119
1120 return 0;
1121 }
1122
trf7970a_switch_rf(struct nfc_digital_dev * ddev,bool on)1123 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1124 {
1125 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1126 int ret = 0;
1127
1128 dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1129
1130 mutex_lock(&trf->lock);
1131
1132 if (on) {
1133 switch (trf->state) {
1134 case TRF7970A_ST_PWR_OFF:
1135 case TRF7970A_ST_RF_OFF:
1136 ret = trf7970a_switch_rf_on(trf);
1137 break;
1138 case TRF7970A_ST_IDLE:
1139 case TRF7970A_ST_IDLE_RX_BLOCKED:
1140 break;
1141 default:
1142 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1143 __func__, trf->state, on);
1144 trf7970a_switch_rf_off(trf);
1145 ret = -EINVAL;
1146 }
1147 } else {
1148 switch (trf->state) {
1149 case TRF7970A_ST_PWR_OFF:
1150 case TRF7970A_ST_RF_OFF:
1151 break;
1152 default:
1153 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1154 __func__, trf->state, on);
1155 ret = -EINVAL;
1156 fallthrough;
1157 case TRF7970A_ST_IDLE:
1158 case TRF7970A_ST_IDLE_RX_BLOCKED:
1159 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1160 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1161 trf7970a_switch_rf_off(trf);
1162 }
1163 }
1164
1165 mutex_unlock(&trf->lock);
1166 return ret;
1167 }
1168
trf7970a_in_config_rf_tech(struct trf7970a * trf,int tech)1169 static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1170 {
1171 int ret = 0;
1172
1173 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1174
1175 switch (tech) {
1176 case NFC_DIGITAL_RF_TECH_106A:
1177 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1178 trf->modulator_sys_clk_ctrl =
1179 (trf->modulator_sys_clk_ctrl & 0xf8) |
1180 TRF7970A_MODULATOR_DEPTH_OOK;
1181 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1182 break;
1183 case NFC_DIGITAL_RF_TECH_106B:
1184 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1185 trf->modulator_sys_clk_ctrl =
1186 (trf->modulator_sys_clk_ctrl & 0xf8) |
1187 TRF7970A_MODULATOR_DEPTH_ASK10;
1188 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1189 break;
1190 case NFC_DIGITAL_RF_TECH_212F:
1191 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1192 trf->modulator_sys_clk_ctrl =
1193 (trf->modulator_sys_clk_ctrl & 0xf8) |
1194 TRF7970A_MODULATOR_DEPTH_ASK10;
1195 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1196 break;
1197 case NFC_DIGITAL_RF_TECH_424F:
1198 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
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_NFCF;
1203 break;
1204 case NFC_DIGITAL_RF_TECH_ISO15693:
1205 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1206 trf->modulator_sys_clk_ctrl =
1207 (trf->modulator_sys_clk_ctrl & 0xf8) |
1208 TRF7970A_MODULATOR_DEPTH_OOK;
1209 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1210 break;
1211 default:
1212 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1213 return -EINVAL;
1214 }
1215
1216 trf->technology = tech;
1217
1218 /* If in initiator mode and not changing the RF tech due to a
1219 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1220 * trf7970a_init()), clear the NFC Target Detection Level register
1221 * due to erratum.
1222 */
1223 if (trf->iso_ctrl == 0xff)
1224 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1225
1226 return ret;
1227 }
1228
trf7970a_is_rf_field(struct trf7970a * trf,bool * is_rf_field)1229 static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1230 {
1231 int ret;
1232 u8 rssi;
1233
1234 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1235 trf->chip_status_ctrl |
1236 TRF7970A_CHIP_STATUS_REC_ON);
1237 if (ret)
1238 return ret;
1239
1240 ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1241 if (ret)
1242 return ret;
1243
1244 usleep_range(50, 60);
1245
1246 ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1247 if (ret)
1248 return ret;
1249
1250 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1251 trf->chip_status_ctrl);
1252 if (ret)
1253 return ret;
1254
1255 if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1256 *is_rf_field = true;
1257 else
1258 *is_rf_field = false;
1259
1260 return 0;
1261 }
1262
trf7970a_in_config_framing(struct trf7970a * trf,int framing)1263 static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1264 {
1265 u8 iso_ctrl = trf->iso_ctrl_tech;
1266 bool is_rf_field = false;
1267 int ret;
1268
1269 dev_dbg(trf->dev, "framing: %d\n", framing);
1270
1271 switch (framing) {
1272 case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1273 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1274 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1275 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1276 break;
1277 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1278 case NFC_DIGITAL_FRAMING_NFCA_T4T:
1279 case NFC_DIGITAL_FRAMING_NFCB:
1280 case NFC_DIGITAL_FRAMING_NFCB_T4T:
1281 case NFC_DIGITAL_FRAMING_NFCF:
1282 case NFC_DIGITAL_FRAMING_NFCF_T3T:
1283 case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1284 case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1285 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1286 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1287 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1288 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1289 break;
1290 case NFC_DIGITAL_FRAMING_NFCA_T2T:
1291 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1292 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1293 break;
1294 default:
1295 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1296 return -EINVAL;
1297 }
1298
1299 trf->framing = framing;
1300
1301 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1302 ret = trf7970a_is_rf_field(trf, &is_rf_field);
1303 if (ret)
1304 return ret;
1305
1306 if (is_rf_field)
1307 return -EBUSY;
1308 }
1309
1310 if (iso_ctrl != trf->iso_ctrl) {
1311 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1312 if (ret)
1313 return ret;
1314
1315 trf->iso_ctrl = iso_ctrl;
1316
1317 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1318 trf->modulator_sys_clk_ctrl);
1319 if (ret)
1320 return ret;
1321 }
1322
1323 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1324 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1325 trf->chip_status_ctrl |
1326 TRF7970A_CHIP_STATUS_RF_ON);
1327 if (ret)
1328 return ret;
1329
1330 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1331
1332 usleep_range(trf->guard_time, trf->guard_time + 1000);
1333 }
1334
1335 return 0;
1336 }
1337
trf7970a_in_configure_hw(struct nfc_digital_dev * ddev,int type,int param)1338 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1339 int param)
1340 {
1341 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1342 int ret;
1343
1344 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1345
1346 mutex_lock(&trf->lock);
1347
1348 trf->is_initiator = true;
1349
1350 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1351 (trf->state == TRF7970A_ST_RF_OFF)) {
1352 ret = trf7970a_switch_rf_on(trf);
1353 if (ret)
1354 goto err_unlock;
1355 }
1356
1357 switch (type) {
1358 case NFC_DIGITAL_CONFIG_RF_TECH:
1359 ret = trf7970a_in_config_rf_tech(trf, param);
1360 break;
1361 case NFC_DIGITAL_CONFIG_FRAMING:
1362 ret = trf7970a_in_config_framing(trf, param);
1363 break;
1364 default:
1365 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1366 ret = -EINVAL;
1367 }
1368
1369 err_unlock:
1370 mutex_unlock(&trf->lock);
1371 return ret;
1372 }
1373
trf7970a_is_iso15693_write_or_lock(u8 cmd)1374 static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1375 {
1376 switch (cmd) {
1377 case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1378 case ISO15693_CMD_LOCK_BLOCK:
1379 case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1380 case ISO15693_CMD_WRITE_AFI:
1381 case ISO15693_CMD_LOCK_AFI:
1382 case ISO15693_CMD_WRITE_DSFID:
1383 case ISO15693_CMD_LOCK_DSFID:
1384 return 1;
1385 default:
1386 return 0;
1387 }
1388 }
1389
trf7970a_per_cmd_config(struct trf7970a * trf,const struct sk_buff * skb)1390 static int trf7970a_per_cmd_config(struct trf7970a *trf,
1391 const struct sk_buff *skb)
1392 {
1393 const u8 *req = skb->data;
1394 u8 special_fcn_reg1, iso_ctrl;
1395 int ret;
1396
1397 trf->issue_eof = false;
1398
1399 /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1400 * special functions register 1 is cleared; otherwise, its a write or
1401 * sector select command and '4_bit_RX' must be set.
1402 *
1403 * When issuing an ISO 15693 command, inspect the flags byte to see
1404 * what speed to use. Also, remember if the OPTION flag is set on
1405 * a Type 5 write or lock command so the driver will know that it
1406 * has to send an EOF in order to get a response.
1407 */
1408 if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1409 (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1410 if (req[0] == NFC_T2T_CMD_READ)
1411 special_fcn_reg1 = 0;
1412 else
1413 special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1414
1415 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1416 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1417 special_fcn_reg1);
1418 if (ret)
1419 return ret;
1420
1421 trf->special_fcn_reg1 = special_fcn_reg1;
1422 }
1423 } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1424 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1425
1426 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1427 case 0x00:
1428 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1429 break;
1430 case ISO15693_REQ_FLAG_SUB_CARRIER:
1431 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1432 break;
1433 case ISO15693_REQ_FLAG_DATA_RATE:
1434 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1435 break;
1436 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1437 ISO15693_REQ_FLAG_DATA_RATE):
1438 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1439 break;
1440 }
1441
1442 if (iso_ctrl != trf->iso_ctrl) {
1443 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1444 if (ret)
1445 return ret;
1446
1447 trf->iso_ctrl = iso_ctrl;
1448 }
1449
1450 if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1451 trf7970a_is_iso15693_write_or_lock(req[1]) &&
1452 (req[0] & ISO15693_REQ_FLAG_OPTION))
1453 trf->issue_eof = true;
1454 }
1455
1456 return 0;
1457 }
1458
trf7970a_send_cmd(struct nfc_digital_dev * ddev,struct sk_buff * skb,u16 timeout,nfc_digital_cmd_complete_t cb,void * arg)1459 static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1460 struct sk_buff *skb, u16 timeout,
1461 nfc_digital_cmd_complete_t cb, void *arg)
1462 {
1463 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1464 u8 prefix[5];
1465 unsigned int len;
1466 int ret;
1467 u8 status;
1468
1469 dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1470 trf->state, timeout, skb->len);
1471
1472 if (skb->len > TRF7970A_TX_MAX)
1473 return -EINVAL;
1474
1475 mutex_lock(&trf->lock);
1476
1477 if ((trf->state != TRF7970A_ST_IDLE) &&
1478 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1479 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1480 trf->state);
1481 ret = -EIO;
1482 goto out_err;
1483 }
1484
1485 if (trf->aborting) {
1486 dev_dbg(trf->dev, "Abort process complete\n");
1487 trf->aborting = false;
1488 ret = -ECANCELED;
1489 goto out_err;
1490 }
1491
1492 if (timeout) {
1493 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1494 GFP_KERNEL);
1495 if (!trf->rx_skb) {
1496 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1497 ret = -ENOMEM;
1498 goto out_err;
1499 }
1500 }
1501
1502 if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1503 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1504 if (ret)
1505 goto out_err;
1506
1507 trf->state = TRF7970A_ST_IDLE;
1508 }
1509
1510 if (trf->is_initiator) {
1511 ret = trf7970a_per_cmd_config(trf, skb);
1512 if (ret)
1513 goto out_err;
1514 }
1515
1516 trf->ddev = ddev;
1517 trf->tx_skb = skb;
1518 trf->cb = cb;
1519 trf->cb_arg = arg;
1520 trf->timeout = timeout;
1521 trf->ignore_timeout = false;
1522
1523 len = skb->len;
1524
1525 /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1526 * on what the current framing is, the address of the TX length byte 1
1527 * register (0x1d), and the 2 byte length of the data to be transmitted.
1528 * That totals 5 bytes.
1529 */
1530 prefix[0] = TRF7970A_CMD_BIT_CTRL |
1531 TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1532 prefix[1] = TRF7970A_CMD_BIT_CTRL |
1533 TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1534 prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1535
1536 if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1537 prefix[3] = 0x00;
1538 prefix[4] = 0x0f; /* 7 bits */
1539 } else {
1540 prefix[3] = (len & 0xf00) >> 4;
1541 prefix[3] |= ((len & 0xf0) >> 4);
1542 prefix[4] = ((len & 0x0f) << 4);
1543 }
1544
1545 len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1546
1547 /* Clear possible spurious interrupt */
1548 ret = trf7970a_read_irqstatus(trf, &status);
1549 if (ret)
1550 goto out_err;
1551
1552 ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1553 if (ret) {
1554 kfree_skb(trf->rx_skb);
1555 trf->rx_skb = NULL;
1556 }
1557
1558 out_err:
1559 mutex_unlock(&trf->lock);
1560 return ret;
1561 }
1562
trf7970a_tg_config_rf_tech(struct trf7970a * trf,int tech)1563 static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1564 {
1565 int ret = 0;
1566
1567 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1568
1569 switch (tech) {
1570 case NFC_DIGITAL_RF_TECH_106A:
1571 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1572 TRF7970A_ISO_CTRL_NFC_CE | TRF7970A_ISO_CTRL_NFC_CE_14443A;
1573 trf->modulator_sys_clk_ctrl =
1574 (trf->modulator_sys_clk_ctrl & 0xf8) |
1575 TRF7970A_MODULATOR_DEPTH_OOK;
1576 break;
1577 case NFC_DIGITAL_RF_TECH_212F:
1578 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1579 TRF7970A_ISO_CTRL_NFC_NFCF_212;
1580 trf->modulator_sys_clk_ctrl =
1581 (trf->modulator_sys_clk_ctrl & 0xf8) |
1582 TRF7970A_MODULATOR_DEPTH_ASK10;
1583 break;
1584 case NFC_DIGITAL_RF_TECH_424F:
1585 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1586 TRF7970A_ISO_CTRL_NFC_NFCF_424;
1587 trf->modulator_sys_clk_ctrl =
1588 (trf->modulator_sys_clk_ctrl & 0xf8) |
1589 TRF7970A_MODULATOR_DEPTH_ASK10;
1590 break;
1591 default:
1592 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1593 return -EINVAL;
1594 }
1595
1596 trf->technology = tech;
1597
1598 /* Normally we write the ISO_CTRL register in
1599 * trf7970a_tg_config_framing() because the framing can change
1600 * the value written. However, when sending a PSL RES,
1601 * digital_tg_send_psl_res_complete() doesn't call
1602 * trf7970a_tg_config_framing() so we must write the register
1603 * here.
1604 */
1605 if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1606 (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1607 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1608 trf->iso_ctrl_tech);
1609
1610 trf->iso_ctrl = trf->iso_ctrl_tech;
1611 }
1612
1613 return ret;
1614 }
1615
1616 /* Since this is a target routine, several of the framing calls are
1617 * made between receiving the request and sending the response so they
1618 * should take effect until after the response is sent. This is accomplished
1619 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1620 * handler.
1621 */
trf7970a_tg_config_framing(struct trf7970a * trf,int framing)1622 static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1623 {
1624 u8 iso_ctrl = trf->iso_ctrl_tech;
1625 int ret;
1626
1627 dev_dbg(trf->dev, "framing: %d\n", framing);
1628
1629 switch (framing) {
1630 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1631 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1632 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1633 break;
1634 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1635 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1636 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1637 /* These ones are applied in the interrupt handler */
1638 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1639 break;
1640 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1641 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1642 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1643 break;
1644 case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1645 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1646 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1647 break;
1648 default:
1649 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1650 return -EINVAL;
1651 }
1652
1653 trf->framing = framing;
1654
1655 if (iso_ctrl != trf->iso_ctrl) {
1656 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1657 if (ret)
1658 return ret;
1659
1660 trf->iso_ctrl = iso_ctrl;
1661
1662 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1663 trf->modulator_sys_clk_ctrl);
1664 if (ret)
1665 return ret;
1666 }
1667
1668 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1669 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1670 trf->chip_status_ctrl |
1671 TRF7970A_CHIP_STATUS_RF_ON);
1672 if (ret)
1673 return ret;
1674
1675 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1676 }
1677
1678 return 0;
1679 }
1680
trf7970a_tg_configure_hw(struct nfc_digital_dev * ddev,int type,int param)1681 static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1682 int param)
1683 {
1684 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1685 int ret;
1686
1687 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1688
1689 mutex_lock(&trf->lock);
1690
1691 trf->is_initiator = false;
1692
1693 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1694 (trf->state == TRF7970A_ST_RF_OFF)) {
1695 ret = trf7970a_switch_rf_on(trf);
1696 if (ret)
1697 goto err_unlock;
1698 }
1699
1700 switch (type) {
1701 case NFC_DIGITAL_CONFIG_RF_TECH:
1702 ret = trf7970a_tg_config_rf_tech(trf, param);
1703 break;
1704 case NFC_DIGITAL_CONFIG_FRAMING:
1705 ret = trf7970a_tg_config_framing(trf, param);
1706 break;
1707 default:
1708 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1709 ret = -EINVAL;
1710 }
1711
1712 err_unlock:
1713 mutex_unlock(&trf->lock);
1714 return ret;
1715 }
1716
_trf7970a_tg_listen(struct nfc_digital_dev * ddev,u16 timeout,nfc_digital_cmd_complete_t cb,void * arg,bool mode_detect)1717 static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1718 nfc_digital_cmd_complete_t cb, void *arg,
1719 bool mode_detect)
1720 {
1721 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1722 int ret;
1723
1724 mutex_lock(&trf->lock);
1725
1726 if ((trf->state != TRF7970A_ST_IDLE) &&
1727 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1728 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1729 trf->state);
1730 ret = -EIO;
1731 goto out_err;
1732 }
1733
1734 if (trf->aborting) {
1735 dev_dbg(trf->dev, "Abort process complete\n");
1736 trf->aborting = false;
1737 ret = -ECANCELED;
1738 goto out_err;
1739 }
1740
1741 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1742 GFP_KERNEL);
1743 if (!trf->rx_skb) {
1744 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1745 ret = -ENOMEM;
1746 goto out_err;
1747 }
1748
1749 ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1750 TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1751 TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1752 TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1753 TRF7970A_RX_SPECIAL_SETTINGS_C212);
1754 if (ret)
1755 goto out_err;
1756
1757 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1758 trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1759 if (ret)
1760 goto out_err;
1761
1762 ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1763 TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1764 if (ret)
1765 goto out_err;
1766
1767 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1768 TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1769 if (ret)
1770 goto out_err;
1771
1772 trf->ddev = ddev;
1773 trf->cb = cb;
1774 trf->cb_arg = arg;
1775 trf->timeout = timeout;
1776 trf->ignore_timeout = false;
1777
1778 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1779 if (ret)
1780 goto out_err;
1781
1782 trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1783 TRF7970A_ST_LISTENING;
1784
1785 schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1786
1787 out_err:
1788 mutex_unlock(&trf->lock);
1789 return ret;
1790 }
1791
trf7970a_tg_listen(struct nfc_digital_dev * ddev,u16 timeout,nfc_digital_cmd_complete_t cb,void * arg)1792 static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1793 nfc_digital_cmd_complete_t cb, void *arg)
1794 {
1795 const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1796
1797 dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1798 trf->state, timeout);
1799
1800 return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1801 }
1802
trf7970a_tg_listen_md(struct nfc_digital_dev * ddev,u16 timeout,nfc_digital_cmd_complete_t cb,void * arg)1803 static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1804 u16 timeout, nfc_digital_cmd_complete_t cb,
1805 void *arg)
1806 {
1807 const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1808 int ret;
1809
1810 dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1811 trf->state, timeout);
1812
1813 ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1814 NFC_DIGITAL_RF_TECH_106A);
1815 if (ret)
1816 return ret;
1817
1818 ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1819 NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1820 if (ret)
1821 return ret;
1822
1823 return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1824 }
1825
trf7970a_tg_get_rf_tech(struct nfc_digital_dev * ddev,u8 * rf_tech)1826 static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1827 {
1828 const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1829
1830 dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1831 trf->state, trf->md_rf_tech);
1832
1833 *rf_tech = trf->md_rf_tech;
1834
1835 return 0;
1836 }
1837
trf7970a_abort_cmd(struct nfc_digital_dev * ddev)1838 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1839 {
1840 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1841
1842 dev_dbg(trf->dev, "Abort process initiated\n");
1843
1844 mutex_lock(&trf->lock);
1845
1846 switch (trf->state) {
1847 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1848 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1849 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1850 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1851 trf->aborting = true;
1852 break;
1853 case TRF7970A_ST_LISTENING:
1854 trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1855 trf7970a_send_err_upstream(trf, -ECANCELED);
1856 dev_dbg(trf->dev, "Abort process complete\n");
1857 break;
1858 default:
1859 break;
1860 }
1861
1862 mutex_unlock(&trf->lock);
1863 }
1864
1865 static const struct nfc_digital_ops trf7970a_nfc_ops = {
1866 .in_configure_hw = trf7970a_in_configure_hw,
1867 .in_send_cmd = trf7970a_send_cmd,
1868 .tg_configure_hw = trf7970a_tg_configure_hw,
1869 .tg_send_cmd = trf7970a_send_cmd,
1870 .tg_listen = trf7970a_tg_listen,
1871 .tg_listen_md = trf7970a_tg_listen_md,
1872 .tg_get_rf_tech = trf7970a_tg_get_rf_tech,
1873 .switch_rf = trf7970a_switch_rf,
1874 .abort_cmd = trf7970a_abort_cmd,
1875 };
1876
trf7970a_power_up(struct trf7970a * trf)1877 static int trf7970a_power_up(struct trf7970a *trf)
1878 {
1879 int ret;
1880
1881 dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1882
1883 if (trf->state != TRF7970A_ST_PWR_OFF)
1884 return 0;
1885
1886 ret = regulator_enable(trf->regulator);
1887 if (ret) {
1888 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1889 return ret;
1890 }
1891
1892 usleep_range(5000, 6000);
1893
1894 if (trf->en2_gpiod &&
1895 !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1896 gpiod_set_value_cansleep(trf->en2_gpiod, 1);
1897 usleep_range(1000, 2000);
1898 }
1899
1900 gpiod_set_value_cansleep(trf->en_gpiod, 1);
1901
1902 usleep_range(20000, 21000);
1903
1904 trf->state = TRF7970A_ST_RF_OFF;
1905
1906 return 0;
1907 }
1908
trf7970a_power_down(struct trf7970a * trf)1909 static int trf7970a_power_down(struct trf7970a *trf)
1910 {
1911 int ret;
1912
1913 dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1914
1915 if (trf->state == TRF7970A_ST_PWR_OFF)
1916 return 0;
1917
1918 if (trf->state != TRF7970A_ST_RF_OFF) {
1919 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1920 trf->state);
1921 return -EBUSY;
1922 }
1923
1924 gpiod_set_value_cansleep(trf->en_gpiod, 0);
1925
1926 if (trf->en2_gpiod && !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW))
1927 gpiod_set_value_cansleep(trf->en2_gpiod, 0);
1928
1929 ret = regulator_disable(trf->regulator);
1930 if (ret)
1931 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1932 ret);
1933
1934 trf->state = TRF7970A_ST_PWR_OFF;
1935
1936 return ret;
1937 }
1938
trf7970a_startup(struct trf7970a * trf)1939 static int trf7970a_startup(struct trf7970a *trf)
1940 {
1941 int ret;
1942
1943 ret = trf7970a_power_up(trf);
1944 if (ret)
1945 return ret;
1946
1947 pm_runtime_set_active(trf->dev);
1948 pm_runtime_enable(trf->dev);
1949 pm_runtime_mark_last_busy(trf->dev);
1950
1951 return 0;
1952 }
1953
trf7970a_shutdown(struct trf7970a * trf)1954 static void trf7970a_shutdown(struct trf7970a *trf)
1955 {
1956 switch (trf->state) {
1957 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1958 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1959 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1960 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1961 case TRF7970A_ST_LISTENING:
1962 trf7970a_send_err_upstream(trf, -ECANCELED);
1963 fallthrough;
1964 case TRF7970A_ST_IDLE:
1965 case TRF7970A_ST_IDLE_RX_BLOCKED:
1966 trf7970a_switch_rf_off(trf);
1967 break;
1968 default:
1969 break;
1970 }
1971
1972 pm_runtime_disable(trf->dev);
1973 pm_runtime_set_suspended(trf->dev);
1974
1975 trf7970a_power_down(trf);
1976 }
1977
trf7970a_get_autosuspend_delay(const struct device_node * np)1978 static int trf7970a_get_autosuspend_delay(const struct device_node *np)
1979 {
1980 int autosuspend_delay, ret;
1981
1982 ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1983 if (ret)
1984 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1985
1986 return autosuspend_delay;
1987 }
1988
trf7970a_probe(struct spi_device * spi)1989 static int trf7970a_probe(struct spi_device *spi)
1990 {
1991 const struct device_node *np = spi->dev.of_node;
1992 struct trf7970a *trf;
1993 int uvolts, autosuspend_delay, ret;
1994 u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
1995
1996 if (!np) {
1997 dev_err(&spi->dev, "No Device Tree entry\n");
1998 return -EINVAL;
1999 }
2000
2001 trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
2002 if (!trf)
2003 return -ENOMEM;
2004
2005 trf->state = TRF7970A_ST_PWR_OFF;
2006 trf->dev = &spi->dev;
2007 trf->spi = spi;
2008
2009 spi->mode = SPI_MODE_1;
2010 spi->bits_per_word = 8;
2011
2012 ret = spi_setup(spi);
2013 if (ret < 0) {
2014 dev_err(trf->dev, "Can't set up SPI Communication\n");
2015 return ret;
2016 }
2017
2018 if (of_property_read_bool(np, "irq-status-read-quirk"))
2019 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2020
2021 /* There are two enable pins - only EN must be present in the DT */
2022 trf->en_gpiod = devm_gpiod_get_index(trf->dev, "ti,enable", 0,
2023 GPIOD_OUT_LOW);
2024 if (IS_ERR(trf->en_gpiod)) {
2025 dev_err(trf->dev, "No EN GPIO property\n");
2026 return PTR_ERR(trf->en_gpiod);
2027 }
2028
2029 trf->en2_gpiod = devm_gpiod_get_index_optional(trf->dev, "ti,enable", 1,
2030 GPIOD_OUT_LOW);
2031 if (!trf->en2_gpiod) {
2032 dev_info(trf->dev, "No EN2 GPIO property\n");
2033 } else if (IS_ERR(trf->en2_gpiod)) {
2034 dev_err(trf->dev, "Error getting EN2 GPIO property: %ld\n",
2035 PTR_ERR(trf->en2_gpiod));
2036 return PTR_ERR(trf->en2_gpiod);
2037 } else if (of_property_read_bool(np, "en2-rf-quirk")) {
2038 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2039 }
2040
2041 of_property_read_u32(np, "clock-frequency", &clk_freq);
2042 if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
2043 (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
2044 dev_err(trf->dev,
2045 "clock-frequency (%u Hz) unsupported\n", clk_freq);
2046 return -EINVAL;
2047 }
2048
2049 if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
2050 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
2051 dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
2052 } else {
2053 trf->modulator_sys_clk_ctrl = 0;
2054 }
2055
2056 ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2057 trf7970a_irq,
2058 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2059 "trf7970a", trf);
2060 if (ret) {
2061 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2062 return ret;
2063 }
2064
2065 mutex_init(&trf->lock);
2066 INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2067
2068 trf->regulator = devm_regulator_get(&spi->dev, "vin");
2069 if (IS_ERR(trf->regulator)) {
2070 ret = PTR_ERR(trf->regulator);
2071 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2072 goto err_destroy_lock;
2073 }
2074
2075 ret = regulator_enable(trf->regulator);
2076 if (ret) {
2077 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2078 goto err_destroy_lock;
2079 }
2080
2081 uvolts = regulator_get_voltage(trf->regulator);
2082 if (uvolts > 4000000)
2083 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2084
2085 trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
2086 if (IS_ERR(trf->regulator)) {
2087 ret = PTR_ERR(trf->regulator);
2088 dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
2089 goto err_destroy_lock;
2090 }
2091
2092 ret = regulator_enable(trf->regulator);
2093 if (ret) {
2094 dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
2095 goto err_destroy_lock;
2096 }
2097
2098 if (regulator_get_voltage(trf->regulator) == 1800000) {
2099 trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
2100 dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
2101 }
2102
2103 trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2104 TRF7970A_SUPPORTED_PROTOCOLS,
2105 NFC_DIGITAL_DRV_CAPS_IN_CRC |
2106 NFC_DIGITAL_DRV_CAPS_TG_CRC, 0,
2107 0);
2108 if (!trf->ddev) {
2109 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2110 ret = -ENOMEM;
2111 goto err_disable_regulator;
2112 }
2113
2114 nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2115 nfc_digital_set_drvdata(trf->ddev, trf);
2116 spi_set_drvdata(spi, trf);
2117
2118 autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2119
2120 pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2121 pm_runtime_use_autosuspend(trf->dev);
2122
2123 ret = trf7970a_startup(trf);
2124 if (ret)
2125 goto err_free_ddev;
2126
2127 ret = nfc_digital_register_device(trf->ddev);
2128 if (ret) {
2129 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2130 ret);
2131 goto err_shutdown;
2132 }
2133
2134 return 0;
2135
2136 err_shutdown:
2137 trf7970a_shutdown(trf);
2138 err_free_ddev:
2139 nfc_digital_free_device(trf->ddev);
2140 err_disable_regulator:
2141 regulator_disable(trf->regulator);
2142 err_destroy_lock:
2143 mutex_destroy(&trf->lock);
2144 return ret;
2145 }
2146
trf7970a_remove(struct spi_device * spi)2147 static void trf7970a_remove(struct spi_device *spi)
2148 {
2149 struct trf7970a *trf = spi_get_drvdata(spi);
2150
2151 mutex_lock(&trf->lock);
2152
2153 trf7970a_shutdown(trf);
2154
2155 mutex_unlock(&trf->lock);
2156
2157 nfc_digital_unregister_device(trf->ddev);
2158 nfc_digital_free_device(trf->ddev);
2159
2160 regulator_disable(trf->regulator);
2161
2162 mutex_destroy(&trf->lock);
2163 }
2164
2165 #ifdef CONFIG_PM_SLEEP
trf7970a_suspend(struct device * dev)2166 static int trf7970a_suspend(struct device *dev)
2167 {
2168 struct spi_device *spi = to_spi_device(dev);
2169 struct trf7970a *trf = spi_get_drvdata(spi);
2170
2171 mutex_lock(&trf->lock);
2172
2173 trf7970a_shutdown(trf);
2174
2175 mutex_unlock(&trf->lock);
2176
2177 return 0;
2178 }
2179
trf7970a_resume(struct device * dev)2180 static int trf7970a_resume(struct device *dev)
2181 {
2182 struct spi_device *spi = to_spi_device(dev);
2183 struct trf7970a *trf = spi_get_drvdata(spi);
2184 int ret;
2185
2186 mutex_lock(&trf->lock);
2187
2188 ret = trf7970a_startup(trf);
2189
2190 mutex_unlock(&trf->lock);
2191
2192 return ret;
2193 }
2194 #endif
2195
2196 #ifdef CONFIG_PM
trf7970a_pm_runtime_suspend(struct device * dev)2197 static int trf7970a_pm_runtime_suspend(struct device *dev)
2198 {
2199 struct spi_device *spi = to_spi_device(dev);
2200 struct trf7970a *trf = spi_get_drvdata(spi);
2201 int ret;
2202
2203 mutex_lock(&trf->lock);
2204
2205 ret = trf7970a_power_down(trf);
2206
2207 mutex_unlock(&trf->lock);
2208
2209 return ret;
2210 }
2211
trf7970a_pm_runtime_resume(struct device * dev)2212 static int trf7970a_pm_runtime_resume(struct device *dev)
2213 {
2214 struct spi_device *spi = to_spi_device(dev);
2215 struct trf7970a *trf = spi_get_drvdata(spi);
2216 int ret;
2217
2218 ret = trf7970a_power_up(trf);
2219 if (!ret)
2220 pm_runtime_mark_last_busy(dev);
2221
2222 return ret;
2223 }
2224 #endif
2225
2226 static const struct dev_pm_ops trf7970a_pm_ops = {
2227 SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2228 SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2229 trf7970a_pm_runtime_resume, NULL)
2230 };
2231
2232 static const struct of_device_id trf7970a_of_match[] __maybe_unused = {
2233 {.compatible = "ti,trf7970a",},
2234 {},
2235 };
2236
2237 MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2238
2239 static const struct spi_device_id trf7970a_id_table[] = {
2240 {"trf7970a", 0},
2241 {}
2242 };
2243
2244 MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2245
2246 static struct spi_driver trf7970a_spi_driver = {
2247 .probe = trf7970a_probe,
2248 .remove = trf7970a_remove,
2249 .id_table = trf7970a_id_table,
2250 .driver = {
2251 .name = "trf7970a",
2252 .of_match_table = of_match_ptr(trf7970a_of_match),
2253 .pm = &trf7970a_pm_ops,
2254 },
2255 };
2256
2257 module_spi_driver(trf7970a_spi_driver);
2258
2259 MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2260 MODULE_LICENSE("GPL v2");
2261 MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");
2262
