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
409enum 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
423struct trf7970a {
424 enum trf7970a_state state;
425 struct device *dev;
426 struct spi_device *spi;
427 struct regulator *vin_regulator;
428 struct regulator *vddio_regulator;
429 struct nfc_digital_dev *ddev;
430 u32 quirks;
431 bool is_initiator;
432 bool aborting;
433 struct sk_buff *tx_skb;
434 struct sk_buff *rx_skb;
435 nfc_digital_cmd_complete_t cb;
436 void *cb_arg;
437 u8 chip_status_ctrl;
438 u8 iso_ctrl;
439 u8 iso_ctrl_tech;
440 u8 modulator_sys_clk_ctrl;
441 u8 special_fcn_reg1;
442 u8 io_ctrl;
443 unsigned int guard_time;
444 int technology;
445 int framing;
446 u8 md_rf_tech;
447 u8 tx_cmd;
448 bool issue_eof;
449 struct gpio_desc *en_gpiod;
450 struct gpio_desc *en2_gpiod;
451 struct mutex lock;
452 unsigned int timeout;
453 bool ignore_timeout;
454 struct delayed_work timeout_work;
455};
456
457static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
458{
459 u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
460 int ret;
461
462 dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
463
464 ret = spi_write(spi: trf->spi, buf: &cmd, len: 1);
465 if (ret)
466 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
467 ret);
468 return ret;
469}
470
471static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
472{
473 u8 addr = TRF7970A_CMD_BIT_RW | reg;
474 int ret;
475
476 ret = spi_write_then_read(spi: trf->spi, txbuf: &addr, n_tx: 1, rxbuf: val, n_rx: 1);
477 if (ret)
478 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
479 ret);
480
481 dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
482
483 return ret;
484}
485
486static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf,
487 size_t len)
488{
489 u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
490 struct spi_transfer t[2];
491 struct spi_message m;
492 int ret;
493
494 dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
495
496 spi_message_init(m: &m);
497
498 memset(&t, 0, sizeof(t));
499
500 t[0].tx_buf = &addr;
501 t[0].len = sizeof(addr);
502 spi_message_add_tail(t: &t[0], m: &m);
503
504 t[1].rx_buf = buf;
505 t[1].len = len;
506 spi_message_add_tail(t: &t[1], m: &m);
507
508 ret = spi_sync(spi: trf->spi, message: &m);
509 if (ret)
510 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
511 ret);
512 return ret;
513}
514
515static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
516{
517 u8 buf[2] = { reg, val };
518 int ret;
519
520 dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
521
522 ret = spi_write(spi: trf->spi, buf, len: 2);
523 if (ret)
524 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
525 buf[0], buf[1], ret);
526
527 return ret;
528}
529
530static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
531{
532 int ret;
533 u8 buf[2];
534 u8 addr;
535
536 addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
537
538 if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
539 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
540 ret = spi_write_then_read(spi: trf->spi, txbuf: &addr, n_tx: 1, rxbuf: buf, n_rx: 2);
541 } else {
542 ret = spi_write_then_read(spi: trf->spi, txbuf: &addr, n_tx: 1, rxbuf: buf, n_rx: 1);
543 }
544
545 if (ret)
546 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
547 __func__, ret);
548 else
549 *status = buf[0];
550
551 return ret;
552}
553
554static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
555{
556 int ret;
557 u8 buf[2];
558 u8 addr;
559
560 addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
561 TRF7970A_CMD_BIT_CONTINUOUS;
562
563 ret = spi_write_then_read(spi: trf->spi, txbuf: &addr, n_tx: 1, rxbuf: buf, n_rx: 2);
564 if (ret)
565 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
566 __func__, ret);
567 else
568 *target_proto = buf[0];
569
570 return ret;
571}
572
573static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
574{
575 int ret;
576 u8 target_proto, tech;
577
578 ret = trf7970a_read_target_proto(trf, target_proto: &target_proto);
579 if (ret)
580 return ret;
581
582 switch (target_proto) {
583 case TRF79070A_NFC_TARGET_PROTOCOL_106A:
584 tech = NFC_DIGITAL_RF_TECH_106A;
585 break;
586 case TRF79070A_NFC_TARGET_PROTOCOL_106B:
587 tech = NFC_DIGITAL_RF_TECH_106B;
588 break;
589 case TRF79070A_NFC_TARGET_PROTOCOL_212F:
590 tech = NFC_DIGITAL_RF_TECH_212F;
591 break;
592 case TRF79070A_NFC_TARGET_PROTOCOL_424F:
593 tech = NFC_DIGITAL_RF_TECH_424F;
594 break;
595 default:
596 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
597 __func__, target_proto);
598 return -EIO;
599 }
600
601 *rf_tech = tech;
602
603 return ret;
604}
605
606static void trf7970a_send_upstream(struct trf7970a *trf)
607{
608 dev_kfree_skb_any(skb: trf->tx_skb);
609 trf->tx_skb = NULL;
610
611 if (trf->rx_skb && !IS_ERR(ptr: trf->rx_skb) && !trf->aborting)
612 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
613 16, 1, trf->rx_skb->data, trf->rx_skb->len,
614 false);
615
616 trf->state = TRF7970A_ST_IDLE;
617
618 if (trf->aborting) {
619 dev_dbg(trf->dev, "Abort process complete\n");
620
621 if (!IS_ERR(ptr: trf->rx_skb)) {
622 kfree_skb(skb: trf->rx_skb);
623 trf->rx_skb = ERR_PTR(error: -ECANCELED);
624 }
625
626 trf->aborting = false;
627 }
628
629 trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
630
631 trf->rx_skb = NULL;
632}
633
634static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
635{
636 dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
637
638 cancel_delayed_work(dwork: &trf->timeout_work);
639
640 kfree_skb(skb: trf->rx_skb);
641 trf->rx_skb = ERR_PTR(error: errno);
642
643 trf7970a_send_upstream(trf);
644}
645
646static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
647 unsigned int len, const u8 *prefix,
648 unsigned int prefix_len)
649{
650 struct spi_transfer t[2];
651 struct spi_message m;
652 unsigned int timeout;
653 int ret;
654
655 print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
656 16, 1, skb->data, len, false);
657
658 spi_message_init(m: &m);
659
660 memset(&t, 0, sizeof(t));
661
662 t[0].tx_buf = prefix;
663 t[0].len = prefix_len;
664 spi_message_add_tail(t: &t[0], m: &m);
665
666 t[1].tx_buf = skb->data;
667 t[1].len = len;
668 spi_message_add_tail(t: &t[1], m: &m);
669
670 ret = spi_sync(spi: trf->spi, message: &m);
671 if (ret) {
672 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
673 ret);
674 return ret;
675 }
676
677 skb_pull(skb, len);
678
679 if (skb->len > 0) {
680 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
681 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
682 } else {
683 if (trf->issue_eof) {
684 trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
685 timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
686 } else {
687 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
688
689 if (!trf->timeout)
690 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
691 else
692 timeout = trf->timeout;
693 }
694 }
695
696 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
697 trf->state);
698
699 schedule_delayed_work(dwork: &trf->timeout_work, delay: msecs_to_jiffies(m: timeout));
700
701 return 0;
702}
703
704static void trf7970a_fill_fifo(struct trf7970a *trf)
705{
706 struct sk_buff *skb = trf->tx_skb;
707 unsigned int len;
708 int ret;
709 u8 fifo_bytes;
710 u8 prefix;
711
712 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, val: &fifo_bytes);
713 if (ret) {
714 trf7970a_send_err_upstream(trf, errno: ret);
715 return;
716 }
717
718 dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
719
720 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
721
722 /* Calculate how much more data can be written to the fifo */
723 len = TRF7970A_FIFO_SIZE - fifo_bytes;
724 if (!len) {
725 schedule_delayed_work(dwork: &trf->timeout_work,
726 delay: msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
727 return;
728 }
729
730 len = min(skb->len, len);
731
732 prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
733
734 ret = trf7970a_transmit(trf, skb, len, prefix: &prefix, prefix_len: sizeof(prefix));
735 if (ret)
736 trf7970a_send_err_upstream(trf, errno: ret);
737}
738
739static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
740{
741 struct sk_buff *skb = trf->rx_skb;
742 int ret;
743 u8 fifo_bytes;
744
745 if (status & TRF7970A_IRQ_STATUS_ERROR) {
746 trf7970a_send_err_upstream(trf, errno: -EIO);
747 return;
748 }
749
750 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, val: &fifo_bytes);
751 if (ret) {
752 trf7970a_send_err_upstream(trf, errno: ret);
753 return;
754 }
755
756 dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
757
758 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
759
760 if (!fifo_bytes)
761 goto no_rx_data;
762
763 if (fifo_bytes > skb_tailroom(skb)) {
764 skb = skb_copy_expand(skb, newheadroom: skb_headroom(skb),
765 max_t(int, fifo_bytes,
766 TRF7970A_RX_SKB_ALLOC_SIZE),
767 GFP_KERNEL);
768 if (!skb) {
769 trf7970a_send_err_upstream(trf, errno: -ENOMEM);
770 return;
771 }
772
773 kfree_skb(skb: trf->rx_skb);
774 trf->rx_skb = skb;
775 }
776
777 ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
778 buf: skb_put(skb, len: fifo_bytes), len: fifo_bytes);
779 if (ret) {
780 trf7970a_send_err_upstream(trf, errno: ret);
781 return;
782 }
783
784 /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
785 if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
786 (trf->special_fcn_reg1 == TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
787 skb->data[0] >>= 4;
788 status = TRF7970A_IRQ_STATUS_SRX;
789 } else {
790 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
791
792 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, val: &fifo_bytes);
793 if (ret) {
794 trf7970a_send_err_upstream(trf, errno: ret);
795 return;
796 }
797
798 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
799
800 /* If there are bytes in the FIFO, set status to '0' so
801 * the if stmt below doesn't fire and the driver will wait
802 * for the trf7970a to generate another RX interrupt.
803 */
804 if (fifo_bytes)
805 status = 0;
806 }
807
808no_rx_data:
809 if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
810 trf7970a_send_upstream(trf);
811 return;
812 }
813
814 dev_dbg(trf->dev, "Setting timeout for %d ms\n",
815 TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
816
817 schedule_delayed_work(dwork: &trf->timeout_work,
818 delay: msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
819}
820
821static irqreturn_t trf7970a_irq(int irq, void *dev_id)
822{
823 struct trf7970a *trf = dev_id;
824 int ret;
825 u8 status, fifo_bytes, iso_ctrl;
826
827 mutex_lock(&trf->lock);
828
829 if (trf->state == TRF7970A_ST_RF_OFF) {
830 mutex_unlock(lock: &trf->lock);
831 return IRQ_NONE;
832 }
833
834 ret = trf7970a_read_irqstatus(trf, status: &status);
835 if (ret) {
836 mutex_unlock(lock: &trf->lock);
837 return IRQ_NONE;
838 }
839
840 dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
841 status);
842
843 if (!status) {
844 mutex_unlock(lock: &trf->lock);
845 return IRQ_NONE;
846 }
847
848 switch (trf->state) {
849 case TRF7970A_ST_IDLE:
850 case TRF7970A_ST_IDLE_RX_BLOCKED:
851 /* If initiator and getting interrupts caused by RF noise,
852 * turn off the receiver to avoid unnecessary interrupts.
853 * It will be turned back on in trf7970a_send_cmd() when
854 * the next command is issued.
855 */
856 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
857 trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
858 trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
859 }
860
861 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
862 break;
863 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
864 if (status & TRF7970A_IRQ_STATUS_TX) {
865 trf->ignore_timeout =
866 !cancel_delayed_work(dwork: &trf->timeout_work);
867 trf7970a_fill_fifo(trf);
868 } else {
869 trf7970a_send_err_upstream(trf, errno: -EIO);
870 }
871 break;
872 case TRF7970A_ST_WAIT_FOR_RX_DATA:
873 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
874 if (status & TRF7970A_IRQ_STATUS_SRX) {
875 trf->ignore_timeout =
876 !cancel_delayed_work(dwork: &trf->timeout_work);
877 trf7970a_drain_fifo(trf, status);
878 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
879 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
880 val: &fifo_bytes);
881
882 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
883
884 if (ret)
885 trf7970a_send_err_upstream(trf, errno: ret);
886 else if (!fifo_bytes)
887 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
888 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
889 (!trf->is_initiator &&
890 (status == (TRF7970A_IRQ_STATUS_TX |
891 TRF7970A_IRQ_STATUS_NFC_RF)))) {
892 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
893
894 if (!trf->timeout) {
895 trf->ignore_timeout =
896 !cancel_delayed_work(dwork: &trf->timeout_work);
897 trf->rx_skb = ERR_PTR(error: 0);
898 trf7970a_send_upstream(trf);
899 break;
900 }
901
902 if (trf->is_initiator)
903 break;
904
905 iso_ctrl = trf->iso_ctrl;
906
907 switch (trf->framing) {
908 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
909 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
910 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
911 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
912 break;
913 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
914 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
915 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
916 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
917 break;
918 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
919 ret = trf7970a_write(trf,
920 TRF7970A_SPECIAL_FCN_REG1,
921 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
922 if (ret)
923 goto err_unlock_exit;
924
925 trf->special_fcn_reg1 =
926 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
927 break;
928 default:
929 break;
930 }
931
932 if (iso_ctrl != trf->iso_ctrl) {
933 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
934 val: iso_ctrl);
935 if (ret)
936 goto err_unlock_exit;
937
938 trf->iso_ctrl = iso_ctrl;
939 }
940 } else {
941 trf7970a_send_err_upstream(trf, errno: -EIO);
942 }
943 break;
944 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
945 if (status != TRF7970A_IRQ_STATUS_TX)
946 trf7970a_send_err_upstream(trf, errno: -EIO);
947 break;
948 case TRF7970A_ST_LISTENING:
949 if (status & TRF7970A_IRQ_STATUS_SRX) {
950 trf->ignore_timeout =
951 !cancel_delayed_work(dwork: &trf->timeout_work);
952 trf7970a_drain_fifo(trf, status);
953 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
954 trf7970a_send_err_upstream(trf, errno: -EIO);
955 }
956 break;
957 case TRF7970A_ST_LISTENING_MD:
958 if (status & TRF7970A_IRQ_STATUS_SRX) {
959 trf->ignore_timeout =
960 !cancel_delayed_work(dwork: &trf->timeout_work);
961
962 ret = trf7970a_mode_detect(trf, rf_tech: &trf->md_rf_tech);
963 if (ret) {
964 trf7970a_send_err_upstream(trf, errno: ret);
965 } else {
966 trf->state = TRF7970A_ST_LISTENING;
967 trf7970a_drain_fifo(trf, status);
968 }
969 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
970 trf7970a_send_err_upstream(trf, errno: -EIO);
971 }
972 break;
973 default:
974 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
975 __func__, trf->state);
976 }
977
978err_unlock_exit:
979 mutex_unlock(lock: &trf->lock);
980 return IRQ_HANDLED;
981}
982
983static void trf7970a_issue_eof(struct trf7970a *trf)
984{
985 int ret;
986
987 dev_dbg(trf->dev, "Issuing EOF\n");
988
989 ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
990 if (ret)
991 trf7970a_send_err_upstream(trf, errno: ret);
992
993 ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
994 if (ret)
995 trf7970a_send_err_upstream(trf, errno: ret);
996
997 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
998
999 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
1000 trf->timeout, trf->state);
1001
1002 schedule_delayed_work(dwork: &trf->timeout_work,
1003 delay: msecs_to_jiffies(m: trf->timeout));
1004}
1005
1006static void trf7970a_timeout_work_handler(struct work_struct *work)
1007{
1008 struct trf7970a *trf = container_of(work, struct trf7970a,
1009 timeout_work.work);
1010
1011 dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1012 trf->state, trf->ignore_timeout);
1013
1014 mutex_lock(&trf->lock);
1015
1016 if (trf->ignore_timeout)
1017 trf->ignore_timeout = false;
1018 else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1019 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1020 else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1021 trf7970a_issue_eof(trf);
1022 else
1023 trf7970a_send_err_upstream(trf, errno: -ETIMEDOUT);
1024
1025 mutex_unlock(lock: &trf->lock);
1026}
1027
1028static int trf7970a_init(struct trf7970a *trf)
1029{
1030 int ret;
1031
1032 dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1033
1034 ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1035 if (ret)
1036 goto err_out;
1037
1038 ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1039 if (ret)
1040 goto err_out;
1041
1042 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1043 val: trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1044 if (ret)
1045 goto err_out;
1046
1047 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, val: 0);
1048 if (ret)
1049 goto err_out;
1050
1051 usleep_range(min: 1000, max: 2000);
1052
1053 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1054
1055 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1056 val: trf->modulator_sys_clk_ctrl);
1057 if (ret)
1058 goto err_out;
1059
1060 ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1061 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1062 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1063 if (ret)
1064 goto err_out;
1065
1066 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, val: 0);
1067 if (ret)
1068 goto err_out;
1069
1070 trf->special_fcn_reg1 = 0;
1071
1072 trf->iso_ctrl = 0xff;
1073 return 0;
1074
1075err_out:
1076 dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1077 return ret;
1078}
1079
1080static void trf7970a_switch_rf_off(struct trf7970a *trf)
1081{
1082 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1083 (trf->state == TRF7970A_ST_RF_OFF))
1084 return;
1085
1086 dev_dbg(trf->dev, "Switching rf off\n");
1087
1088 trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1089
1090 trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, val: trf->chip_status_ctrl);
1091
1092 trf->aborting = false;
1093 trf->state = TRF7970A_ST_RF_OFF;
1094
1095 pm_runtime_mark_last_busy(dev: trf->dev);
1096 pm_runtime_put_autosuspend(dev: trf->dev);
1097}
1098
1099static int trf7970a_switch_rf_on(struct trf7970a *trf)
1100{
1101 int ret;
1102
1103 dev_dbg(trf->dev, "Switching rf on\n");
1104
1105 pm_runtime_get_sync(dev: trf->dev);
1106
1107 if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1108 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1109 trf->state);
1110 return -EINVAL;
1111 }
1112
1113 ret = trf7970a_init(trf);
1114 if (ret) {
1115 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1116 return ret;
1117 }
1118
1119 trf->state = TRF7970A_ST_IDLE;
1120
1121 return 0;
1122}
1123
1124static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1125{
1126 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1127 int ret = 0;
1128
1129 dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1130
1131 mutex_lock(&trf->lock);
1132
1133 if (on) {
1134 switch (trf->state) {
1135 case TRF7970A_ST_PWR_OFF:
1136 case TRF7970A_ST_RF_OFF:
1137 ret = trf7970a_switch_rf_on(trf);
1138 break;
1139 case TRF7970A_ST_IDLE:
1140 case TRF7970A_ST_IDLE_RX_BLOCKED:
1141 break;
1142 default:
1143 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1144 __func__, trf->state, on);
1145 trf7970a_switch_rf_off(trf);
1146 ret = -EINVAL;
1147 }
1148 } else {
1149 switch (trf->state) {
1150 case TRF7970A_ST_PWR_OFF:
1151 case TRF7970A_ST_RF_OFF:
1152 break;
1153 default:
1154 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1155 __func__, trf->state, on);
1156 ret = -EINVAL;
1157 fallthrough;
1158 case TRF7970A_ST_IDLE:
1159 case TRF7970A_ST_IDLE_RX_BLOCKED:
1160 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1161 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1162 trf7970a_switch_rf_off(trf);
1163 }
1164 }
1165
1166 mutex_unlock(lock: &trf->lock);
1167 return ret;
1168}
1169
1170static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1171{
1172 int ret = 0;
1173
1174 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1175
1176 switch (tech) {
1177 case NFC_DIGITAL_RF_TECH_106A:
1178 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1179 trf->modulator_sys_clk_ctrl =
1180 (trf->modulator_sys_clk_ctrl & 0xf8) |
1181 TRF7970A_MODULATOR_DEPTH_OOK;
1182 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1183 break;
1184 case NFC_DIGITAL_RF_TECH_106B:
1185 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1186 trf->modulator_sys_clk_ctrl =
1187 (trf->modulator_sys_clk_ctrl & 0xf8) |
1188 TRF7970A_MODULATOR_DEPTH_ASK10;
1189 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1190 break;
1191 case NFC_DIGITAL_RF_TECH_212F:
1192 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1193 trf->modulator_sys_clk_ctrl =
1194 (trf->modulator_sys_clk_ctrl & 0xf8) |
1195 TRF7970A_MODULATOR_DEPTH_ASK10;
1196 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1197 break;
1198 case NFC_DIGITAL_RF_TECH_424F:
1199 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1200 trf->modulator_sys_clk_ctrl =
1201 (trf->modulator_sys_clk_ctrl & 0xf8) |
1202 TRF7970A_MODULATOR_DEPTH_ASK10;
1203 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1204 break;
1205 case NFC_DIGITAL_RF_TECH_ISO15693:
1206 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1207 trf->modulator_sys_clk_ctrl =
1208 (trf->modulator_sys_clk_ctrl & 0xf8) |
1209 TRF7970A_MODULATOR_DEPTH_OOK;
1210 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1211 break;
1212 default:
1213 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1214 return -EINVAL;
1215 }
1216
1217 trf->technology = tech;
1218
1219 /* If in initiator mode and not changing the RF tech due to a
1220 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1221 * trf7970a_init()), clear the NFC Target Detection Level register
1222 * due to erratum.
1223 */
1224 if (trf->iso_ctrl == 0xff)
1225 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, val: 0);
1226
1227 return ret;
1228}
1229
1230static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1231{
1232 int ret;
1233 u8 rssi;
1234
1235 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1236 val: trf->chip_status_ctrl |
1237 TRF7970A_CHIP_STATUS_REC_ON);
1238 if (ret)
1239 return ret;
1240
1241 ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1242 if (ret)
1243 return ret;
1244
1245 usleep_range(min: 50, max: 60);
1246
1247 ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, val: &rssi);
1248 if (ret)
1249 return ret;
1250
1251 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1252 val: trf->chip_status_ctrl);
1253 if (ret)
1254 return ret;
1255
1256 if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1257 *is_rf_field = true;
1258 else
1259 *is_rf_field = false;
1260
1261 return 0;
1262}
1263
1264static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1265{
1266 u8 iso_ctrl = trf->iso_ctrl_tech;
1267 bool is_rf_field = false;
1268 int ret;
1269
1270 dev_dbg(trf->dev, "framing: %d\n", framing);
1271
1272 switch (framing) {
1273 case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1274 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1275 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1276 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1277 break;
1278 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1279 case NFC_DIGITAL_FRAMING_NFCA_T4T:
1280 case NFC_DIGITAL_FRAMING_NFCB:
1281 case NFC_DIGITAL_FRAMING_NFCB_T4T:
1282 case NFC_DIGITAL_FRAMING_NFCF:
1283 case NFC_DIGITAL_FRAMING_NFCF_T3T:
1284 case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1285 case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1286 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1287 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1288 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1289 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1290 break;
1291 case NFC_DIGITAL_FRAMING_NFCA_T2T:
1292 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1293 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1294 break;
1295 default:
1296 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1297 return -EINVAL;
1298 }
1299
1300 trf->framing = framing;
1301
1302 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1303 ret = trf7970a_is_rf_field(trf, is_rf_field: &is_rf_field);
1304 if (ret)
1305 return ret;
1306
1307 if (is_rf_field)
1308 return -EBUSY;
1309 }
1310
1311 if (iso_ctrl != trf->iso_ctrl) {
1312 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, val: iso_ctrl);
1313 if (ret)
1314 return ret;
1315
1316 trf->iso_ctrl = iso_ctrl;
1317
1318 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1319 val: trf->modulator_sys_clk_ctrl);
1320 if (ret)
1321 return ret;
1322 }
1323
1324 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1325 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1326 val: trf->chip_status_ctrl |
1327 TRF7970A_CHIP_STATUS_RF_ON);
1328 if (ret)
1329 return ret;
1330
1331 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1332
1333 usleep_range(min: trf->guard_time, max: trf->guard_time + 1000);
1334 }
1335
1336 return 0;
1337}
1338
1339static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1340 int param)
1341{
1342 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1343 int ret;
1344
1345 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1346
1347 mutex_lock(&trf->lock);
1348
1349 trf->is_initiator = true;
1350
1351 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1352 (trf->state == TRF7970A_ST_RF_OFF)) {
1353 ret = trf7970a_switch_rf_on(trf);
1354 if (ret)
1355 goto err_unlock;
1356 }
1357
1358 switch (type) {
1359 case NFC_DIGITAL_CONFIG_RF_TECH:
1360 ret = trf7970a_in_config_rf_tech(trf, tech: param);
1361 break;
1362 case NFC_DIGITAL_CONFIG_FRAMING:
1363 ret = trf7970a_in_config_framing(trf, framing: param);
1364 break;
1365 default:
1366 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1367 ret = -EINVAL;
1368 }
1369
1370err_unlock:
1371 mutex_unlock(lock: &trf->lock);
1372 return ret;
1373}
1374
1375static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1376{
1377 switch (cmd) {
1378 case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1379 case ISO15693_CMD_LOCK_BLOCK:
1380 case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1381 case ISO15693_CMD_WRITE_AFI:
1382 case ISO15693_CMD_LOCK_AFI:
1383 case ISO15693_CMD_WRITE_DSFID:
1384 case ISO15693_CMD_LOCK_DSFID:
1385 return 1;
1386 default:
1387 return 0;
1388 }
1389}
1390
1391static int trf7970a_per_cmd_config(struct trf7970a *trf,
1392 const struct sk_buff *skb)
1393{
1394 const u8 *req = skb->data;
1395 u8 special_fcn_reg1, iso_ctrl;
1396 int ret;
1397
1398 trf->issue_eof = false;
1399
1400 /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1401 * special functions register 1 is cleared; otherwise, its a write or
1402 * sector select command and '4_bit_RX' must be set.
1403 *
1404 * When issuing an ISO 15693 command, inspect the flags byte to see
1405 * what speed to use. Also, remember if the OPTION flag is set on
1406 * a Type 5 write or lock command so the driver will know that it
1407 * has to send an EOF in order to get a response.
1408 */
1409 if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1410 (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1411 if (req[0] == NFC_T2T_CMD_READ)
1412 special_fcn_reg1 = 0;
1413 else
1414 special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1415
1416 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1417 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1418 val: special_fcn_reg1);
1419 if (ret)
1420 return ret;
1421
1422 trf->special_fcn_reg1 = special_fcn_reg1;
1423 }
1424 } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1425 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1426
1427 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1428 case 0x00:
1429 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1430 break;
1431 case ISO15693_REQ_FLAG_SUB_CARRIER:
1432 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1433 break;
1434 case ISO15693_REQ_FLAG_DATA_RATE:
1435 iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1436 break;
1437 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1438 ISO15693_REQ_FLAG_DATA_RATE):
1439 iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1440 break;
1441 }
1442
1443 if (iso_ctrl != trf->iso_ctrl) {
1444 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, val: iso_ctrl);
1445 if (ret)
1446 return ret;
1447
1448 trf->iso_ctrl = iso_ctrl;
1449 }
1450
1451 if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1452 trf7970a_is_iso15693_write_or_lock(cmd: req[1]) &&
1453 (req[0] & ISO15693_REQ_FLAG_OPTION))
1454 trf->issue_eof = true;
1455 }
1456
1457 return 0;
1458}
1459
1460static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1461 struct sk_buff *skb, u16 timeout,
1462 nfc_digital_cmd_complete_t cb, void *arg)
1463{
1464 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1465 u8 prefix[5];
1466 unsigned int len;
1467 int ret;
1468 u8 status;
1469
1470 dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1471 trf->state, timeout, skb->len);
1472
1473 if (skb->len > TRF7970A_TX_MAX)
1474 return -EINVAL;
1475
1476 mutex_lock(&trf->lock);
1477
1478 if ((trf->state != TRF7970A_ST_IDLE) &&
1479 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1480 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1481 trf->state);
1482 ret = -EIO;
1483 goto out_err;
1484 }
1485
1486 if (trf->aborting) {
1487 dev_dbg(trf->dev, "Abort process complete\n");
1488 trf->aborting = false;
1489 ret = -ECANCELED;
1490 goto out_err;
1491 }
1492
1493 if (timeout) {
1494 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1495 GFP_KERNEL);
1496 if (!trf->rx_skb) {
1497 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1498 ret = -ENOMEM;
1499 goto out_err;
1500 }
1501 }
1502
1503 if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1504 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1505 if (ret)
1506 goto out_err;
1507
1508 trf->state = TRF7970A_ST_IDLE;
1509 }
1510
1511 if (trf->is_initiator) {
1512 ret = trf7970a_per_cmd_config(trf, skb);
1513 if (ret)
1514 goto out_err;
1515 }
1516
1517 trf->ddev = ddev;
1518 trf->tx_skb = skb;
1519 trf->cb = cb;
1520 trf->cb_arg = arg;
1521 trf->timeout = timeout;
1522 trf->ignore_timeout = false;
1523
1524 len = skb->len;
1525
1526 /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1527 * on what the current framing is, the address of the TX length byte 1
1528 * register (0x1d), and the 2 byte length of the data to be transmitted.
1529 * That totals 5 bytes.
1530 */
1531 prefix[0] = TRF7970A_CMD_BIT_CTRL |
1532 TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1533 prefix[1] = TRF7970A_CMD_BIT_CTRL |
1534 TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1535 prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1536
1537 if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1538 prefix[3] = 0x00;
1539 prefix[4] = 0x0f; /* 7 bits */
1540 } else {
1541 prefix[3] = (len & 0xf00) >> 4;
1542 prefix[3] |= ((len & 0xf0) >> 4);
1543 prefix[4] = ((len & 0x0f) << 4);
1544 }
1545
1546 len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1547
1548 /* Clear possible spurious interrupt */
1549 ret = trf7970a_read_irqstatus(trf, status: &status);
1550 if (ret)
1551 goto out_err;
1552
1553 ret = trf7970a_transmit(trf, skb, len, prefix, prefix_len: sizeof(prefix));
1554 if (ret) {
1555 kfree_skb(skb: trf->rx_skb);
1556 trf->rx_skb = NULL;
1557 }
1558
1559out_err:
1560 mutex_unlock(lock: &trf->lock);
1561 return ret;
1562}
1563
1564static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1565{
1566 int ret = 0;
1567
1568 dev_dbg(trf->dev, "rf technology: %d\n", tech);
1569
1570 switch (tech) {
1571 case NFC_DIGITAL_RF_TECH_106A:
1572 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1573 TRF7970A_ISO_CTRL_NFC_CE | TRF7970A_ISO_CTRL_NFC_CE_14443A;
1574 trf->modulator_sys_clk_ctrl =
1575 (trf->modulator_sys_clk_ctrl & 0xf8) |
1576 TRF7970A_MODULATOR_DEPTH_OOK;
1577 break;
1578 case NFC_DIGITAL_RF_TECH_212F:
1579 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1580 TRF7970A_ISO_CTRL_NFC_NFCF_212;
1581 trf->modulator_sys_clk_ctrl =
1582 (trf->modulator_sys_clk_ctrl & 0xf8) |
1583 TRF7970A_MODULATOR_DEPTH_ASK10;
1584 break;
1585 case NFC_DIGITAL_RF_TECH_424F:
1586 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1587 TRF7970A_ISO_CTRL_NFC_NFCF_424;
1588 trf->modulator_sys_clk_ctrl =
1589 (trf->modulator_sys_clk_ctrl & 0xf8) |
1590 TRF7970A_MODULATOR_DEPTH_ASK10;
1591 break;
1592 default:
1593 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1594 return -EINVAL;
1595 }
1596
1597 trf->technology = tech;
1598
1599 /* Normally we write the ISO_CTRL register in
1600 * trf7970a_tg_config_framing() because the framing can change
1601 * the value written. However, when sending a PSL RES,
1602 * digital_tg_send_psl_res_complete() doesn't call
1603 * trf7970a_tg_config_framing() so we must write the register
1604 * here.
1605 */
1606 if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1607 (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1608 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1609 val: trf->iso_ctrl_tech);
1610
1611 trf->iso_ctrl = trf->iso_ctrl_tech;
1612 }
1613
1614 return ret;
1615}
1616
1617/* Since this is a target routine, several of the framing calls are
1618 * made between receiving the request and sending the response so they
1619 * should take effect until after the response is sent. This is accomplished
1620 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1621 * handler.
1622 */
1623static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1624{
1625 u8 iso_ctrl = trf->iso_ctrl_tech;
1626 int ret;
1627
1628 dev_dbg(trf->dev, "framing: %d\n", framing);
1629
1630 switch (framing) {
1631 case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1632 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1633 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1634 break;
1635 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1636 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1637 case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1638 /* These ones are applied in the interrupt handler */
1639 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1640 break;
1641 case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1642 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1643 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1644 break;
1645 case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1646 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1647 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1648 break;
1649 default:
1650 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1651 return -EINVAL;
1652 }
1653
1654 trf->framing = framing;
1655
1656 if (iso_ctrl != trf->iso_ctrl) {
1657 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, val: iso_ctrl);
1658 if (ret)
1659 return ret;
1660
1661 trf->iso_ctrl = iso_ctrl;
1662
1663 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1664 val: trf->modulator_sys_clk_ctrl);
1665 if (ret)
1666 return ret;
1667 }
1668
1669 if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1670 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1671 val: trf->chip_status_ctrl |
1672 TRF7970A_CHIP_STATUS_RF_ON);
1673 if (ret)
1674 return ret;
1675
1676 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1677 }
1678
1679 return 0;
1680}
1681
1682static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1683 int param)
1684{
1685 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1686 int ret;
1687
1688 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1689
1690 mutex_lock(&trf->lock);
1691
1692 trf->is_initiator = false;
1693
1694 if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1695 (trf->state == TRF7970A_ST_RF_OFF)) {
1696 ret = trf7970a_switch_rf_on(trf);
1697 if (ret)
1698 goto err_unlock;
1699 }
1700
1701 switch (type) {
1702 case NFC_DIGITAL_CONFIG_RF_TECH:
1703 ret = trf7970a_tg_config_rf_tech(trf, tech: param);
1704 break;
1705 case NFC_DIGITAL_CONFIG_FRAMING:
1706 ret = trf7970a_tg_config_framing(trf, framing: param);
1707 break;
1708 default:
1709 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1710 ret = -EINVAL;
1711 }
1712
1713err_unlock:
1714 mutex_unlock(lock: &trf->lock);
1715 return ret;
1716}
1717
1718static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1719 nfc_digital_cmd_complete_t cb, void *arg,
1720 bool mode_detect)
1721{
1722 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1723 int ret;
1724
1725 mutex_lock(&trf->lock);
1726
1727 if ((trf->state != TRF7970A_ST_IDLE) &&
1728 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1729 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1730 trf->state);
1731 ret = -EIO;
1732 goto out_err;
1733 }
1734
1735 if (trf->aborting) {
1736 dev_dbg(trf->dev, "Abort process complete\n");
1737 trf->aborting = false;
1738 ret = -ECANCELED;
1739 goto out_err;
1740 }
1741
1742 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1743 GFP_KERNEL);
1744 if (!trf->rx_skb) {
1745 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1746 ret = -ENOMEM;
1747 goto out_err;
1748 }
1749
1750 ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1751 TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1752 TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1753 TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1754 TRF7970A_RX_SPECIAL_SETTINGS_C212);
1755 if (ret)
1756 goto out_err;
1757
1758 ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1759 val: trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1760 if (ret)
1761 goto out_err;
1762
1763 ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1764 TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1765 if (ret)
1766 goto out_err;
1767
1768 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1769 TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1770 if (ret)
1771 goto out_err;
1772
1773 trf->ddev = ddev;
1774 trf->cb = cb;
1775 trf->cb_arg = arg;
1776 trf->timeout = timeout;
1777 trf->ignore_timeout = false;
1778
1779 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1780 if (ret)
1781 goto out_err;
1782
1783 trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1784 TRF7970A_ST_LISTENING;
1785
1786 schedule_delayed_work(dwork: &trf->timeout_work, delay: msecs_to_jiffies(m: timeout));
1787
1788out_err:
1789 mutex_unlock(lock: &trf->lock);
1790 return ret;
1791}
1792
1793static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1794 nfc_digital_cmd_complete_t cb, void *arg)
1795{
1796 const struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1797
1798 dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1799 trf->state, timeout);
1800
1801 return _trf7970a_tg_listen(ddev, timeout, cb, arg, mode_detect: false);
1802}
1803
1804static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1805 u16 timeout, nfc_digital_cmd_complete_t cb,
1806 void *arg)
1807{
1808 const struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1809 int ret;
1810
1811 dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1812 trf->state, timeout);
1813
1814 ret = trf7970a_tg_configure_hw(ddev, type: NFC_DIGITAL_CONFIG_RF_TECH,
1815 param: NFC_DIGITAL_RF_TECH_106A);
1816 if (ret)
1817 return ret;
1818
1819 ret = trf7970a_tg_configure_hw(ddev, type: NFC_DIGITAL_CONFIG_FRAMING,
1820 param: NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1821 if (ret)
1822 return ret;
1823
1824 return _trf7970a_tg_listen(ddev, timeout, cb, arg, mode_detect: true);
1825}
1826
1827static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1828{
1829 const struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1830
1831 dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1832 trf->state, trf->md_rf_tech);
1833
1834 *rf_tech = trf->md_rf_tech;
1835
1836 return 0;
1837}
1838
1839static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1840{
1841 struct trf7970a *trf = nfc_digital_get_drvdata(dev: ddev);
1842
1843 dev_dbg(trf->dev, "Abort process initiated\n");
1844
1845 mutex_lock(&trf->lock);
1846
1847 switch (trf->state) {
1848 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1849 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1850 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1851 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1852 trf->aborting = true;
1853 break;
1854 case TRF7970A_ST_LISTENING:
1855 trf->ignore_timeout = !cancel_delayed_work(dwork: &trf->timeout_work);
1856 trf7970a_send_err_upstream(trf, errno: -ECANCELED);
1857 dev_dbg(trf->dev, "Abort process complete\n");
1858 break;
1859 default:
1860 break;
1861 }
1862
1863 mutex_unlock(lock: &trf->lock);
1864}
1865
1866static const struct nfc_digital_ops trf7970a_nfc_ops = {
1867 .in_configure_hw = trf7970a_in_configure_hw,
1868 .in_send_cmd = trf7970a_send_cmd,
1869 .tg_configure_hw = trf7970a_tg_configure_hw,
1870 .tg_send_cmd = trf7970a_send_cmd,
1871 .tg_listen = trf7970a_tg_listen,
1872 .tg_listen_md = trf7970a_tg_listen_md,
1873 .tg_get_rf_tech = trf7970a_tg_get_rf_tech,
1874 .switch_rf = trf7970a_switch_rf,
1875 .abort_cmd = trf7970a_abort_cmd,
1876};
1877
1878static int trf7970a_power_up(struct trf7970a *trf)
1879{
1880 int ret;
1881
1882 dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1883
1884 if (trf->state != TRF7970A_ST_PWR_OFF)
1885 return 0;
1886
1887 ret = regulator_enable(regulator: trf->vin_regulator);
1888 if (ret) {
1889 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1890 return ret;
1891 }
1892
1893 usleep_range(min: 5000, max: 6000);
1894
1895 if (trf->en2_gpiod &&
1896 !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1897 gpiod_set_value_cansleep(desc: trf->en2_gpiod, value: 1);
1898 usleep_range(min: 1000, max: 2000);
1899 }
1900
1901 gpiod_set_value_cansleep(desc: trf->en_gpiod, value: 1);
1902
1903 usleep_range(min: 20000, max: 21000);
1904
1905 trf->state = TRF7970A_ST_RF_OFF;
1906
1907 return 0;
1908}
1909
1910static int trf7970a_power_down(struct trf7970a *trf)
1911{
1912 int ret;
1913
1914 dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1915
1916 if (trf->state == TRF7970A_ST_PWR_OFF)
1917 return 0;
1918
1919 if (trf->state != TRF7970A_ST_RF_OFF) {
1920 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1921 trf->state);
1922 return -EBUSY;
1923 }
1924
1925 gpiod_set_value_cansleep(desc: trf->en_gpiod, value: 0);
1926
1927 if (trf->en2_gpiod && !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW))
1928 gpiod_set_value_cansleep(desc: trf->en2_gpiod, value: 0);
1929
1930 ret = regulator_disable(regulator: trf->vin_regulator);
1931 if (ret)
1932 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1933 ret);
1934
1935 trf->state = TRF7970A_ST_PWR_OFF;
1936
1937 return ret;
1938}
1939
1940static int trf7970a_startup(struct trf7970a *trf)
1941{
1942 int ret;
1943
1944 ret = trf7970a_power_up(trf);
1945 if (ret)
1946 return ret;
1947
1948 pm_runtime_set_active(dev: trf->dev);
1949 pm_runtime_enable(dev: trf->dev);
1950 pm_runtime_mark_last_busy(dev: trf->dev);
1951
1952 return 0;
1953}
1954
1955static void trf7970a_shutdown(struct trf7970a *trf)
1956{
1957 switch (trf->state) {
1958 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1959 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1960 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1961 case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1962 case TRF7970A_ST_LISTENING:
1963 trf7970a_send_err_upstream(trf, errno: -ECANCELED);
1964 fallthrough;
1965 case TRF7970A_ST_IDLE:
1966 case TRF7970A_ST_IDLE_RX_BLOCKED:
1967 trf7970a_switch_rf_off(trf);
1968 break;
1969 default:
1970 break;
1971 }
1972
1973 pm_runtime_disable(dev: trf->dev);
1974 pm_runtime_set_suspended(dev: trf->dev);
1975
1976 trf7970a_power_down(trf);
1977}
1978
1979static int trf7970a_get_autosuspend_delay(const struct device_node *np)
1980{
1981 int autosuspend_delay, ret;
1982
1983 ret = of_property_read_u32(np, propname: "autosuspend-delay", out_value: &autosuspend_delay);
1984 if (ret)
1985 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1986
1987 return autosuspend_delay;
1988}
1989
1990static int trf7970a_probe(struct spi_device *spi)
1991{
1992 const struct device_node *np = spi->dev.of_node;
1993 struct trf7970a *trf;
1994 int uvolts, autosuspend_delay, ret;
1995 u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
1996
1997 if (!np) {
1998 dev_err(&spi->dev, "No Device Tree entry\n");
1999 return -EINVAL;
2000 }
2001
2002 trf = devm_kzalloc(dev: &spi->dev, size: sizeof(*trf), GFP_KERNEL);
2003 if (!trf)
2004 return -ENOMEM;
2005
2006 trf->state = TRF7970A_ST_PWR_OFF;
2007 trf->dev = &spi->dev;
2008 trf->spi = spi;
2009
2010 spi->mode = SPI_MODE_1;
2011 spi->bits_per_word = 8;
2012
2013 ret = spi_setup(spi);
2014 if (ret < 0) {
2015 dev_err(trf->dev, "Can't set up SPI Communication\n");
2016 return ret;
2017 }
2018
2019 if (of_property_read_bool(np, propname: "irq-status-read-quirk"))
2020 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2021
2022 /* There are two enable pins - only EN must be present in the DT */
2023 trf->en_gpiod = devm_gpiod_get_index(dev: trf->dev, con_id: "ti,enable", idx: 0,
2024 flags: GPIOD_OUT_LOW);
2025 if (IS_ERR(ptr: trf->en_gpiod)) {
2026 dev_err(trf->dev, "No EN GPIO property\n");
2027 return PTR_ERR(ptr: trf->en_gpiod);
2028 }
2029
2030 trf->en2_gpiod = devm_gpiod_get_index_optional(dev: trf->dev, con_id: "ti,enable", index: 1,
2031 flags: GPIOD_OUT_LOW);
2032 if (!trf->en2_gpiod) {
2033 dev_info(trf->dev, "No EN2 GPIO property\n");
2034 } else if (IS_ERR(ptr: trf->en2_gpiod)) {
2035 dev_err(trf->dev, "Error getting EN2 GPIO property: %ld\n",
2036 PTR_ERR(trf->en2_gpiod));
2037 return PTR_ERR(ptr: trf->en2_gpiod);
2038 } else if (of_property_read_bool(np, propname: "en2-rf-quirk")) {
2039 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2040 }
2041
2042 of_property_read_u32(np, propname: "clock-frequency", out_value: &clk_freq);
2043 if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
2044 (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
2045 dev_err(trf->dev,
2046 "clock-frequency (%u Hz) unsupported\n", clk_freq);
2047 return -EINVAL;
2048 }
2049
2050 if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
2051 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
2052 dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
2053 } else {
2054 trf->modulator_sys_clk_ctrl = 0;
2055 }
2056
2057 ret = devm_request_threaded_irq(dev: trf->dev, irq: spi->irq, NULL,
2058 thread_fn: trf7970a_irq,
2059 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2060 devname: "trf7970a", dev_id: trf);
2061 if (ret) {
2062 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2063 return ret;
2064 }
2065
2066 mutex_init(&trf->lock);
2067 INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2068
2069 trf->vin_regulator = devm_regulator_get(dev: &spi->dev, id: "vin");
2070 if (IS_ERR(ptr: trf->vin_regulator)) {
2071 ret = PTR_ERR(ptr: trf->vin_regulator);
2072 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2073 goto err_destroy_lock;
2074 }
2075
2076 ret = regulator_enable(regulator: trf->vin_regulator);
2077 if (ret) {
2078 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2079 goto err_destroy_lock;
2080 }
2081
2082 uvolts = regulator_get_voltage(regulator: trf->vin_regulator);
2083 if (uvolts > 4000000)
2084 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2085
2086 trf->vddio_regulator = devm_regulator_get(dev: &spi->dev, id: "vdd-io");
2087 if (IS_ERR(ptr: trf->vddio_regulator)) {
2088 ret = PTR_ERR(ptr: trf->vddio_regulator);
2089 dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
2090 goto err_disable_vin_regulator;
2091 }
2092
2093 ret = regulator_enable(regulator: trf->vddio_regulator);
2094 if (ret) {
2095 dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
2096 goto err_disable_vin_regulator;
2097 }
2098
2099 if (regulator_get_voltage(regulator: trf->vddio_regulator) == 1800000) {
2100 trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
2101 dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
2102 }
2103
2104 trf->ddev = nfc_digital_allocate_device(ops: &trf7970a_nfc_ops,
2105 TRF7970A_SUPPORTED_PROTOCOLS,
2106 NFC_DIGITAL_DRV_CAPS_IN_CRC |
2107 NFC_DIGITAL_DRV_CAPS_TG_CRC, tx_headroom: 0,
2108 tx_tailroom: 0);
2109 if (!trf->ddev) {
2110 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2111 ret = -ENOMEM;
2112 goto err_disable_vddio_regulator;
2113 }
2114
2115 nfc_digital_set_parent_dev(ndev: trf->ddev, dev: trf->dev);
2116 nfc_digital_set_drvdata(dev: trf->ddev, data: trf);
2117 spi_set_drvdata(spi, data: trf);
2118
2119 autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2120
2121 pm_runtime_set_autosuspend_delay(dev: trf->dev, delay: autosuspend_delay);
2122 pm_runtime_use_autosuspend(dev: trf->dev);
2123
2124 ret = trf7970a_startup(trf);
2125 if (ret)
2126 goto err_free_ddev;
2127
2128 ret = nfc_digital_register_device(ndev: trf->ddev);
2129 if (ret) {
2130 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2131 ret);
2132 goto err_shutdown;
2133 }
2134
2135 return 0;
2136
2137err_shutdown:
2138 trf7970a_shutdown(trf);
2139err_free_ddev:
2140 nfc_digital_free_device(ndev: trf->ddev);
2141err_disable_vddio_regulator:
2142 regulator_disable(regulator: trf->vddio_regulator);
2143err_disable_vin_regulator:
2144 regulator_disable(regulator: trf->vin_regulator);
2145err_destroy_lock:
2146 mutex_destroy(lock: &trf->lock);
2147 return ret;
2148}
2149
2150static void trf7970a_remove(struct spi_device *spi)
2151{
2152 struct trf7970a *trf = spi_get_drvdata(spi);
2153
2154 mutex_lock(&trf->lock);
2155
2156 trf7970a_shutdown(trf);
2157
2158 mutex_unlock(lock: &trf->lock);
2159
2160 nfc_digital_unregister_device(ndev: trf->ddev);
2161 nfc_digital_free_device(ndev: trf->ddev);
2162
2163 regulator_disable(regulator: trf->vddio_regulator);
2164 regulator_disable(regulator: trf->vin_regulator);
2165
2166 mutex_destroy(lock: &trf->lock);
2167}
2168
2169#ifdef CONFIG_PM_SLEEP
2170static int trf7970a_suspend(struct device *dev)
2171{
2172 struct spi_device *spi = to_spi_device(dev);
2173 struct trf7970a *trf = spi_get_drvdata(spi);
2174
2175 mutex_lock(&trf->lock);
2176
2177 trf7970a_shutdown(trf);
2178
2179 mutex_unlock(lock: &trf->lock);
2180
2181 return 0;
2182}
2183
2184static int trf7970a_resume(struct device *dev)
2185{
2186 struct spi_device *spi = to_spi_device(dev);
2187 struct trf7970a *trf = spi_get_drvdata(spi);
2188 int ret;
2189
2190 mutex_lock(&trf->lock);
2191
2192 ret = trf7970a_startup(trf);
2193
2194 mutex_unlock(lock: &trf->lock);
2195
2196 return ret;
2197}
2198#endif
2199
2200#ifdef CONFIG_PM
2201static int trf7970a_pm_runtime_suspend(struct device *dev)
2202{
2203 struct spi_device *spi = to_spi_device(dev);
2204 struct trf7970a *trf = spi_get_drvdata(spi);
2205 int ret;
2206
2207 mutex_lock(&trf->lock);
2208
2209 ret = trf7970a_power_down(trf);
2210
2211 mutex_unlock(lock: &trf->lock);
2212
2213 return ret;
2214}
2215
2216static int trf7970a_pm_runtime_resume(struct device *dev)
2217{
2218 struct spi_device *spi = to_spi_device(dev);
2219 struct trf7970a *trf = spi_get_drvdata(spi);
2220 int ret;
2221
2222 ret = trf7970a_power_up(trf);
2223 if (!ret)
2224 pm_runtime_mark_last_busy(dev);
2225
2226 return ret;
2227}
2228#endif
2229
2230static const struct dev_pm_ops trf7970a_pm_ops = {
2231 SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2232 SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2233 trf7970a_pm_runtime_resume, NULL)
2234};
2235
2236static const struct of_device_id trf7970a_of_match[] __maybe_unused = {
2237 {.compatible = "ti,trf7970a",},
2238 {},
2239};
2240
2241MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2242
2243static const struct spi_device_id trf7970a_id_table[] = {
2244 {"trf7970a", 0},
2245 {}
2246};
2247
2248MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2249
2250static struct spi_driver trf7970a_spi_driver = {
2251 .probe = trf7970a_probe,
2252 .remove = trf7970a_remove,
2253 .id_table = trf7970a_id_table,
2254 .driver = {
2255 .name = "trf7970a",
2256 .of_match_table = of_match_ptr(trf7970a_of_match),
2257 .pm = &trf7970a_pm_ops,
2258 },
2259};
2260
2261module_spi_driver(trf7970a_spi_driver);
2262
2263MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2264MODULE_LICENSE("GPL v2");
2265MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");
2266

source code of linux/drivers/nfc/trf7970a.c