1/*
2 * TI TRF7970a RFID/NFC Transceiver Driver
3 *
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5 *
6 * Author: Erick Macias <emacias@ti.com>
7 * Author: Felipe Balbi <balbi@ti.com>
8 * Author: Mark A. Greer <mgreer@animalcreek.com>
9 *
10 * This program is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2  of
12 * the License as published by the Free Software Foundation.
13 */
14
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/netdevice.h>
18#include <linux/interrupt.h>
19#include <linux/pm_runtime.h>
20#include <linux/nfc.h>
21#include <linux/skbuff.h>
22#include <linux/delay.h>
23#include <linux/gpio.h>
24#include <linux/of.h>
25#include <linux/of_gpio.h>
26#include <linux/spi/spi.h>
27#include <linux/regulator/consumer.h>
28
29#include <net/nfc/nfc.h>
30#include <net/nfc/digital.h>
31
32/* There are 3 ways the host can communicate with the trf7970a:
33 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
34 * SS mode.  The driver only supports the two SPI modes.
35 *
36 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
37 * pins must asserted in that order and with specific delays in between.
38 * The delays used in the driver were provided by TI and have been
39 * confirmed to work with this driver.  There is a bug with the current
40 * version of the trf7970a that requires that EN2 remain low no matter
41 * what.  If it goes high, it will generate an RF field even when in
42 * passive target mode.  TI has indicated that the chip will work okay
43 * when EN2 is left low.  The 'en2-rf-quirk' device tree property
44 * indicates that trf7970a currently being used has the erratum and
45 * that EN2 must be kept low.
46 *
47 * Timeouts are implemented using the delayed workqueue kernel facility.
48 * Timeouts are required so things don't hang when there is no response
49 * from the trf7970a (or tag).  Using this mechanism creates a race with
50 * interrupts, however.  That is, an interrupt and a timeout could occur
51 * closely enough together that one is blocked by the mutex while the other
52 * executes.  When the timeout handler executes first and blocks the
53 * interrupt handler, it will eventually set the state to IDLE so the
54 * interrupt handler will check the state and exit with no harm done.
55 * When the interrupt handler executes first and blocks the timeout handler,
56 * the cancel_delayed_work() call will know that it didn't cancel the
57 * work item (i.e., timeout) and will return zero.  That return code is
58 * used by the timer handler to indicate that it should ignore the timeout
59 * once its unblocked.
60 *
61 * Aborting an active command isn't as simple as it seems because the only
62 * way to abort a command that's already been sent to the tag is so turn
63 * off power to the tag.  If we do that, though, we'd have to go through
64 * the entire anticollision procedure again but the digital layer doesn't
65 * support that.  So, if an abort is received before trf7970a_send_cmd()
66 * has sent the command to the tag, it simply returns -ECANCELED.  If the
67 * command has already been sent to the tag, then the driver continues
68 * normally and recieves the response data (or error) but just before
69 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
70 * upstream instead.  If the command failed, that error will be sent
71 * upstream.
72 *
73 * When recieving data from a tag and the interrupt status register has
74 * only the SRX bit set, it means that all of the data has been received
75 * (once what's in the fifo has been read).  However, depending on timing
76 * an interrupt status with only the SRX bit set may not be recived.  In
77 * those cases, the timeout mechanism is used to wait 20 ms in case more
78 * data arrives.  After 20 ms, it is assumed that all of the data has been
79 * received and the accumulated rx data is sent upstream.  The
80 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
81 * (i.e., it indicates that some data has been received but we're not sure
82 * if there is more coming so a timeout in this state means all data has
83 * been received and there isn't an error).  The delay is 20 ms since delays
84 * of ~16 ms have been observed during testing.
85 *
86 * When transmitting a frame larger than the FIFO size (127 bytes), the
87 * driver will wait 20 ms for the FIFO to drain past the low-watermark
88 * and generate an interrupt.  The low-watermark set to 32 bytes so the
89 * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
90 * the lowest possible bit rate (6.62 kbps for 15693), it will take up
91 * to ~14.35 ms so 20 ms is used for the timeout.
92 *
93 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
94 * Having only 4 bits in the FIFO won't normally generate an interrupt so
95 * driver enables the '4_bit_RX' bit of the Special Functions register 1
96 * to cause an interrupt in that case.  Leaving that bit for a read command
97 * messes up the data returned so it is only enabled when the framing is
98 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
99 * Unfortunately, that means that the driver has to peek into tx frames
100 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
101 * the trf7970a_per_cmd_config() routine.
102 *
103 * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
104 * frequencies and whether to use low or high data rates in the flags byte
105 * of the frame.  This means that the driver has to peek at all 15693 frames
106 * to determine what speed to set the communication to.  In addition, write
107 * and lock commands use the OPTION flag to indicate that an EOF must be
108 * sent to the tag before it will send its response.  So the driver has to
109 * examine all frames for that reason too.
110 *
111 * It is unclear how long to wait before sending the EOF.  According to the
112 * Note under Table 1-1 in section 1.6 of
113 * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
114 * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
115 * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
116 * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
117 * ensure the wait is long enough before sending the EOF.  This seems to work
118 * reliably.
119 */
120
121#define TRF7970A_SUPPORTED_PROTOCOLS \
122		(NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |	\
123		 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
124		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
125
126#define TRF7970A_AUTOSUSPEND_DELAY		30000 /* 30 seconds */
127
128#define TRF7970A_RX_SKB_ALLOC_SIZE		256
129
130#define TRF7970A_FIFO_SIZE			127
131
132/* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
133#define TRF7970A_TX_MAX				(4096 - 1)
134
135#define TRF7970A_WAIT_FOR_TX_IRQ		20
136#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT	20
137#define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT	20
138#define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF	40
139
140/* Guard times for various RF technologies (in us) */
141#define TRF7970A_GUARD_TIME_NFCA		5000
142#define TRF7970A_GUARD_TIME_NFCB		5000
143#define TRF7970A_GUARD_TIME_NFCF		20000
144#define TRF7970A_GUARD_TIME_15693		1000
145
146/* Quirks */
147/* Erratum: When reading IRQ Status register on trf7970a, we must issue a
148 * read continuous command for IRQ Status and Collision Position registers.
149 */
150#define TRF7970A_QUIRK_IRQ_STATUS_READ		BIT(0)
151#define TRF7970A_QUIRK_EN2_MUST_STAY_LOW	BIT(1)
152
153/* Direct commands */
154#define TRF7970A_CMD_IDLE			0x00
155#define TRF7970A_CMD_SOFT_INIT			0x03
156#define TRF7970A_CMD_RF_COLLISION		0x04
157#define TRF7970A_CMD_RF_COLLISION_RESPONSE_N	0x05
158#define TRF7970A_CMD_RF_COLLISION_RESPONSE_0	0x06
159#define TRF7970A_CMD_FIFO_RESET			0x0f
160#define TRF7970A_CMD_TRANSMIT_NO_CRC		0x10
161#define TRF7970A_CMD_TRANSMIT			0x11
162#define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC	0x12
163#define TRF7970A_CMD_DELAY_TRANSMIT		0x13
164#define TRF7970A_CMD_EOF			0x14
165#define TRF7970A_CMD_CLOSE_SLOT			0x15
166#define TRF7970A_CMD_BLOCK_RX			0x16
167#define TRF7970A_CMD_ENABLE_RX			0x17
168#define TRF7970A_CMD_TEST_INT_RF		0x18
169#define TRF7970A_CMD_TEST_EXT_RF		0x19
170#define TRF7970A_CMD_RX_GAIN_ADJUST		0x1a
171
172/* Bits determining whether its a direct command or register R/W,
173 * whether to use a continuous SPI transaction or not, and the actual
174 * direct cmd opcode or regster address.
175 */
176#define TRF7970A_CMD_BIT_CTRL			BIT(7)
177#define TRF7970A_CMD_BIT_RW			BIT(6)
178#define TRF7970A_CMD_BIT_CONTINUOUS		BIT(5)
179#define TRF7970A_CMD_BIT_OPCODE(opcode)		((opcode) & 0x1f)
180
181/* Registers addresses */
182#define TRF7970A_CHIP_STATUS_CTRL		0x00
183#define TRF7970A_ISO_CTRL			0x01
184#define TRF7970A_ISO14443B_TX_OPTIONS		0x02
185#define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS	0x03
186#define TRF7970A_TX_TIMER_SETTING_H_BYTE	0x04
187#define TRF7970A_TX_TIMER_SETTING_L_BYTE	0x05
188#define TRF7970A_TX_PULSE_LENGTH_CTRL		0x06
189#define TRF7970A_RX_NO_RESPONSE_WAIT		0x07
190#define TRF7970A_RX_WAIT_TIME			0x08
191#define TRF7970A_MODULATOR_SYS_CLK_CTRL		0x09
192#define TRF7970A_RX_SPECIAL_SETTINGS		0x0a
193#define TRF7970A_REG_IO_CTRL			0x0b
194#define TRF7970A_IRQ_STATUS			0x0c
195#define TRF7970A_COLLISION_IRQ_MASK		0x0d
196#define TRF7970A_COLLISION_POSITION		0x0e
197#define TRF7970A_RSSI_OSC_STATUS		0x0f
198#define TRF7970A_SPECIAL_FCN_REG1		0x10
199#define TRF7970A_SPECIAL_FCN_REG2		0x11
200#define TRF7970A_RAM1				0x12
201#define TRF7970A_RAM2				0x13
202#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS	0x14
203#define TRF7970A_NFC_LOW_FIELD_LEVEL		0x16
204#define TRF7970A_NFCID1				0x17
205#define TRF7970A_NFC_TARGET_LEVEL		0x18
206#define TRF79070A_NFC_TARGET_PROTOCOL		0x19
207#define TRF7970A_TEST_REGISTER1			0x1a
208#define TRF7970A_TEST_REGISTER2			0x1b
209#define TRF7970A_FIFO_STATUS			0x1c
210#define TRF7970A_TX_LENGTH_BYTE1		0x1d
211#define TRF7970A_TX_LENGTH_BYTE2		0x1e
212#define TRF7970A_FIFO_IO_REGISTER		0x1f
213
214/* Chip Status Control Register Bits */
215#define TRF7970A_CHIP_STATUS_VRS5_3		BIT(0)
216#define TRF7970A_CHIP_STATUS_REC_ON		BIT(1)
217#define TRF7970A_CHIP_STATUS_AGC_ON		BIT(2)
218#define TRF7970A_CHIP_STATUS_PM_ON		BIT(3)
219#define TRF7970A_CHIP_STATUS_RF_PWR		BIT(4)
220#define TRF7970A_CHIP_STATUS_RF_ON		BIT(5)
221#define TRF7970A_CHIP_STATUS_DIRECT		BIT(6)
222#define TRF7970A_CHIP_STATUS_STBY		BIT(7)
223
224/* ISO Control Register Bits */
225#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662	0x00
226#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662	0x01
227#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648	0x02
228#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648	0x03
229#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a	0x04
230#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667	0x05
231#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669	0x06
232#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669	0x07
233#define TRF7970A_ISO_CTRL_14443A_106		0x08
234#define TRF7970A_ISO_CTRL_14443A_212		0x09
235#define TRF7970A_ISO_CTRL_14443A_424		0x0a
236#define TRF7970A_ISO_CTRL_14443A_848		0x0b
237#define TRF7970A_ISO_CTRL_14443B_106		0x0c
238#define TRF7970A_ISO_CTRL_14443B_212		0x0d
239#define TRF7970A_ISO_CTRL_14443B_424		0x0e
240#define TRF7970A_ISO_CTRL_14443B_848		0x0f
241#define TRF7970A_ISO_CTRL_FELICA_212		0x1a
242#define TRF7970A_ISO_CTRL_FELICA_424		0x1b
243#define TRF7970A_ISO_CTRL_NFC_NFCA_106		0x01
244#define TRF7970A_ISO_CTRL_NFC_NFCF_212		0x02
245#define TRF7970A_ISO_CTRL_NFC_NFCF_424		0x03
246#define TRF7970A_ISO_CTRL_NFC_CE_14443A		0x00
247#define TRF7970A_ISO_CTRL_NFC_CE_14443B		0x01
248#define TRF7970A_ISO_CTRL_NFC_CE		BIT(2)
249#define TRF7970A_ISO_CTRL_NFC_ACTIVE		BIT(3)
250#define TRF7970A_ISO_CTRL_NFC_INITIATOR		BIT(4)
251#define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE	BIT(5)
252#define TRF7970A_ISO_CTRL_RFID			BIT(5)
253#define TRF7970A_ISO_CTRL_DIR_MODE		BIT(6)
254#define TRF7970A_ISO_CTRL_RX_CRC_N		BIT(7)	/* true == No CRC */
255
256#define TRF7970A_ISO_CTRL_RFID_SPEED_MASK	0x1f
257
258/* Modulator and SYS_CLK Control Register Bits */
259#define TRF7970A_MODULATOR_DEPTH(n)		((n) & 0x7)
260#define TRF7970A_MODULATOR_DEPTH_ASK10		(TRF7970A_MODULATOR_DEPTH(0))
261#define TRF7970A_MODULATOR_DEPTH_OOK		(TRF7970A_MODULATOR_DEPTH(1))
262#define TRF7970A_MODULATOR_DEPTH_ASK7		(TRF7970A_MODULATOR_DEPTH(2))
263#define TRF7970A_MODULATOR_DEPTH_ASK8_5		(TRF7970A_MODULATOR_DEPTH(3))
264#define TRF7970A_MODULATOR_DEPTH_ASK13		(TRF7970A_MODULATOR_DEPTH(4))
265#define TRF7970A_MODULATOR_DEPTH_ASK16		(TRF7970A_MODULATOR_DEPTH(5))
266#define TRF7970A_MODULATOR_DEPTH_ASK22		(TRF7970A_MODULATOR_DEPTH(6))
267#define TRF7970A_MODULATOR_DEPTH_ASK30		(TRF7970A_MODULATOR_DEPTH(7))
268#define TRF7970A_MODULATOR_EN_ANA		BIT(3)
269#define TRF7970A_MODULATOR_CLK(n)		(((n) & 0x3) << 4)
270#define TRF7970A_MODULATOR_CLK_DISABLED		(TRF7970A_MODULATOR_CLK(0))
271#define TRF7970A_MODULATOR_CLK_3_6		(TRF7970A_MODULATOR_CLK(1))
272#define TRF7970A_MODULATOR_CLK_6_13		(TRF7970A_MODULATOR_CLK(2))
273#define TRF7970A_MODULATOR_CLK_13_27		(TRF7970A_MODULATOR_CLK(3))
274#define TRF7970A_MODULATOR_EN_OOK		BIT(6)
275#define TRF7970A_MODULATOR_27MHZ		BIT(7)
276
277#define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM	BIT(0)
278#define TRF7970A_RX_SPECIAL_SETTINGS_AGCR	BIT(1)
279#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB	(0x0 << 2)
280#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB	(0x1 << 2)
281#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB	(0x2 << 2)
282#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB	(0x3 << 2)
283#define TRF7970A_RX_SPECIAL_SETTINGS_HBT	BIT(4)
284#define TRF7970A_RX_SPECIAL_SETTINGS_M848	BIT(5)
285#define TRF7970A_RX_SPECIAL_SETTINGS_C424	BIT(6)
286#define TRF7970A_RX_SPECIAL_SETTINGS_C212	BIT(7)
287
288#define TRF7970A_REG_IO_CTRL_VRS(v)		((v) & 0x07)
289#define TRF7970A_REG_IO_CTRL_IO_LOW		BIT(5)
290#define TRF7970A_REG_IO_CTRL_EN_EXT_PA		BIT(6)
291#define TRF7970A_REG_IO_CTRL_AUTO_REG		BIT(7)
292
293/* IRQ Status Register Bits */
294#define TRF7970A_IRQ_STATUS_NORESP		BIT(0) /* ISO15693 only */
295#define TRF7970A_IRQ_STATUS_NFC_COL_ERROR	BIT(0)
296#define TRF7970A_IRQ_STATUS_COL			BIT(1)
297#define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR	BIT(2)
298#define TRF7970A_IRQ_STATUS_NFC_RF		BIT(2)
299#define TRF7970A_IRQ_STATUS_PARITY_ERROR	BIT(3)
300#define TRF7970A_IRQ_STATUS_NFC_SDD		BIT(3)
301#define TRF7970A_IRQ_STATUS_CRC_ERROR		BIT(4)
302#define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR	BIT(4)
303#define TRF7970A_IRQ_STATUS_FIFO		BIT(5)
304#define TRF7970A_IRQ_STATUS_SRX			BIT(6)
305#define TRF7970A_IRQ_STATUS_TX			BIT(7)
306
307#define TRF7970A_IRQ_STATUS_ERROR				\
308		(TRF7970A_IRQ_STATUS_COL |			\
309		 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |	\
310		 TRF7970A_IRQ_STATUS_PARITY_ERROR |		\
311		 TRF7970A_IRQ_STATUS_CRC_ERROR)
312
313#define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK	(BIT(2) | BIT(1) | BIT(0))
314#define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK	(BIT(5) | BIT(4) | BIT(3))
315#define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK	BIT(6)
316
317#define TRF7970A_SPECIAL_FCN_REG1_COL_7_6		BIT(0)
318#define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL		BIT(1)
319#define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX		BIT(2)
320#define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE		BIT(3)
321#define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US	BIT(4)
322#define TRF7970A_SPECIAL_FCN_REG1_PAR43			BIT(5)
323
324#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124	(0x0 << 2)
325#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120	(0x1 << 2)
326#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112	(0x2 << 2)
327#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96	(0x3 << 2)
328#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4	0x0
329#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8	0x1
330#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16	0x2
331#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32	0x3
332
333#define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)	((v) & 0x07)
334#define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS	BIT(7)
335
336#define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)	((v) & 0x07)
337#define TRF7970A_NFC_TARGET_LEVEL_HI_RF		BIT(3)
338#define TRF7970A_NFC_TARGET_LEVEL_SDD_EN	BIT(3)
339#define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES	(0x0 << 6)
340#define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES	(0x1 << 6)
341#define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES	(0x2 << 6)
342
343#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106		BIT(0)
344#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212		BIT(1)
345#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424		(BIT(0) | BIT(1))
346#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B	BIT(2)
347#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106		BIT(3)
348#define TRF79070A_NFC_TARGET_PROTOCOL_FELICA		BIT(4)
349#define TRF79070A_NFC_TARGET_PROTOCOL_RF_L		BIT(6)
350#define TRF79070A_NFC_TARGET_PROTOCOL_RF_H		BIT(7)
351
352#define TRF79070A_NFC_TARGET_PROTOCOL_106A		\
353	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
354	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
355	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |	\
356	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
357
358#define TRF79070A_NFC_TARGET_PROTOCOL_106B		\
359	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
360	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
361	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |	\
362	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
363
364#define TRF79070A_NFC_TARGET_PROTOCOL_212F		\
365	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
366	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
367	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
368	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
369
370#define TRF79070A_NFC_TARGET_PROTOCOL_424F		\
371	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
372	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
373	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
374	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
375
376#define TRF7970A_FIFO_STATUS_OVERFLOW		BIT(7)
377
378/* NFC (ISO/IEC 14443A) Type 2 Tag commands */
379#define NFC_T2T_CMD_READ			0x30
380
381/* ISO 15693 commands codes */
382#define ISO15693_CMD_INVENTORY			0x01
383#define ISO15693_CMD_READ_SINGLE_BLOCK		0x20
384#define ISO15693_CMD_WRITE_SINGLE_BLOCK		0x21
385#define ISO15693_CMD_LOCK_BLOCK			0x22
386#define ISO15693_CMD_READ_MULTIPLE_BLOCK	0x23
387#define ISO15693_CMD_WRITE_MULTIPLE_BLOCK	0x24
388#define ISO15693_CMD_SELECT			0x25
389#define ISO15693_CMD_RESET_TO_READY		0x26
390#define ISO15693_CMD_WRITE_AFI			0x27
391#define ISO15693_CMD_LOCK_AFI			0x28
392#define ISO15693_CMD_WRITE_DSFID		0x29
393#define ISO15693_CMD_LOCK_DSFID			0x2a
394#define ISO15693_CMD_GET_SYSTEM_INFO		0x2b
395#define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS	0x2c
396
397/* ISO 15693 request and response flags */
398#define ISO15693_REQ_FLAG_SUB_CARRIER		BIT(0)
399#define ISO15693_REQ_FLAG_DATA_RATE		BIT(1)
400#define ISO15693_REQ_FLAG_INVENTORY		BIT(2)
401#define ISO15693_REQ_FLAG_PROTOCOL_EXT		BIT(3)
402#define ISO15693_REQ_FLAG_SELECT		BIT(4)
403#define ISO15693_REQ_FLAG_AFI			BIT(4)
404#define ISO15693_REQ_FLAG_ADDRESS		BIT(5)
405#define ISO15693_REQ_FLAG_NB_SLOTS		BIT(5)
406#define ISO15693_REQ_FLAG_OPTION		BIT(6)
407
408#define ISO15693_REQ_FLAG_SPEED_MASK \
409		(ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
410
411enum trf7970a_state {
412	TRF7970A_ST_PWR_OFF,
413	TRF7970A_ST_RF_OFF,
414	TRF7970A_ST_IDLE,
415	TRF7970A_ST_IDLE_RX_BLOCKED,
416	TRF7970A_ST_WAIT_FOR_TX_FIFO,
417	TRF7970A_ST_WAIT_FOR_RX_DATA,
418	TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
419	TRF7970A_ST_WAIT_TO_ISSUE_EOF,
420	TRF7970A_ST_LISTENING,
421	TRF7970A_ST_LISTENING_MD,
422	TRF7970A_ST_MAX
423};
424
425struct trf7970a {
426	enum trf7970a_state		state;
427	struct device			*dev;
428	struct spi_device		*spi;
429	struct regulator		*regulator;
430	struct nfc_digital_dev		*ddev;
431	u32				quirks;
432	bool				is_initiator;
433	bool				aborting;
434	struct sk_buff			*tx_skb;
435	struct sk_buff			*rx_skb;
436	nfc_digital_cmd_complete_t	cb;
437	void				*cb_arg;
438	u8				chip_status_ctrl;
439	u8				iso_ctrl;
440	u8				iso_ctrl_tech;
441	u8				modulator_sys_clk_ctrl;
442	u8				special_fcn_reg1;
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	int				en2_gpio;
450	int				en_gpio;
451	struct mutex			lock;
452	unsigned int			timeout;
453	bool				ignore_timeout;
454	struct delayed_work		timeout_work;
455};
456
457
458static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
459{
460	u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
461	int ret;
462
463	dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
464
465	ret = spi_write(trf->spi, &cmd, 1);
466	if (ret)
467		dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
468				ret);
469	return ret;
470}
471
472static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
473{
474	u8 addr = TRF7970A_CMD_BIT_RW | reg;
475	int ret;
476
477	ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
478	if (ret)
479		dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
480				ret);
481
482	dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
483
484	return ret;
485}
486
487static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, 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);
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[0], &m);
503
504	t[1].rx_buf = buf;
505	t[1].len = len;
506	spi_message_add_tail(&t[1], &m);
507
508	ret = spi_sync(trf->spi, &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(trf->spi, buf, 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(trf->spi, &addr, 1, buf, 2);
541	} else {
542		ret = spi_write_then_read(trf->spi, &addr, 1, buf, 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(trf->spi, &addr, 1, buf, 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);
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(trf->tx_skb);
609	trf->tx_skb = NULL;
610
611	if (trf->rx_skb && !IS_ERR(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(trf->rx_skb)) {
622			kfree_skb(trf->rx_skb);
623			trf->rx_skb = ERR_PTR(-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(&trf->timeout_work);
639
640	kfree_skb(trf->rx_skb);
641	trf->rx_skb = ERR_PTR(errno);
642
643	trf7970a_send_upstream(trf);
644}
645
646static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
647		unsigned int len, u8 *prefix, 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
703static 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
738static 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 ==
786				 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, &fifo_bytes);
793		if (ret) {
794			trf7970a_send_err_upstream(trf, 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(&trf->timeout_work,
818			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(&trf->lock);
831		return IRQ_NONE;
832	}
833
834	ret = trf7970a_read_irqstatus(trf, &status);
835	if (ret) {
836		mutex_unlock(&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(&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(&trf->timeout_work);
867			trf7970a_fill_fifo(trf);
868		} else {
869			trf7970a_send_err_upstream(trf, -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(&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					&fifo_bytes);
881
882			fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
883
884			if (ret)
885				trf7970a_send_err_upstream(trf, 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 = !cancel_delayed_work(
896						&trf->timeout_work);
897				trf->rx_skb = ERR_PTR(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						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, -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, -EIO);
947		break;
948	case TRF7970A_ST_LISTENING:
949		if (status & TRF7970A_IRQ_STATUS_SRX) {
950			trf->ignore_timeout =
951				!cancel_delayed_work(&trf->timeout_work);
952			trf7970a_drain_fifo(trf, status);
953		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
954			trf7970a_send_err_upstream(trf, -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(&trf->timeout_work);
961
962			ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
963			if (ret) {
964				trf7970a_send_err_upstream(trf, 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, -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(&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, ret);
992
993	ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
994	if (ret)
995		trf7970a_send_err_upstream(trf, 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(&trf->timeout_work,
1003			msecs_to_jiffies(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, -ETIMEDOUT);
1024
1025	mutex_unlock(&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	usleep_range(1000, 2000);
1043
1044	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1045
1046	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
1047	if (ret)
1048		goto err_out;
1049
1050	trf->modulator_sys_clk_ctrl = 0;
1051
1052	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1053			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1054			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1055	if (ret)
1056		goto err_out;
1057
1058	ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1059	if (ret)
1060		goto err_out;
1061
1062	trf->special_fcn_reg1 = 0;
1063
1064	trf->iso_ctrl = 0xff;
1065	return 0;
1066
1067err_out:
1068	dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1069	return ret;
1070}
1071
1072static void trf7970a_switch_rf_off(struct trf7970a *trf)
1073{
1074	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1075			(trf->state == TRF7970A_ST_RF_OFF))
1076		return;
1077
1078	dev_dbg(trf->dev, "Switching rf off\n");
1079
1080	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1081
1082	trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1083
1084	trf->aborting = false;
1085	trf->state = TRF7970A_ST_RF_OFF;
1086
1087	pm_runtime_mark_last_busy(trf->dev);
1088	pm_runtime_put_autosuspend(trf->dev);
1089}
1090
1091static int trf7970a_switch_rf_on(struct trf7970a *trf)
1092{
1093	int ret;
1094
1095	dev_dbg(trf->dev, "Switching rf on\n");
1096
1097	pm_runtime_get_sync(trf->dev);
1098
1099	if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1100		dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1101				trf->state);
1102		return -EINVAL;
1103	}
1104
1105	ret = trf7970a_init(trf);
1106	if (ret) {
1107		dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1108		return ret;
1109	}
1110
1111	trf->state = TRF7970A_ST_IDLE;
1112
1113	return 0;
1114}
1115
1116static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1117{
1118	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1119	int ret = 0;
1120
1121	dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1122
1123	mutex_lock(&trf->lock);
1124
1125	if (on) {
1126		switch (trf->state) {
1127		case TRF7970A_ST_PWR_OFF:
1128		case TRF7970A_ST_RF_OFF:
1129			ret = trf7970a_switch_rf_on(trf);
1130			break;
1131		case TRF7970A_ST_IDLE:
1132		case TRF7970A_ST_IDLE_RX_BLOCKED:
1133			break;
1134		default:
1135			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1136					__func__, trf->state, on);
1137			trf7970a_switch_rf_off(trf);
1138			ret = -EINVAL;
1139		}
1140	} else {
1141		switch (trf->state) {
1142		case TRF7970A_ST_PWR_OFF:
1143		case TRF7970A_ST_RF_OFF:
1144			break;
1145		default:
1146			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1147					__func__, trf->state, on);
1148			ret = -EINVAL;
1149			/* FALLTHROUGH */
1150		case TRF7970A_ST_IDLE:
1151		case TRF7970A_ST_IDLE_RX_BLOCKED:
1152		case TRF7970A_ST_WAIT_FOR_RX_DATA:
1153		case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1154			trf7970a_switch_rf_off(trf);
1155		}
1156	}
1157
1158	mutex_unlock(&trf->lock);
1159	return ret;
1160}
1161
1162static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1163{
1164	int ret = 0;
1165
1166	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1167
1168	switch (tech) {
1169	case NFC_DIGITAL_RF_TECH_106A:
1170		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1171		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1172		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1173		break;
1174	case NFC_DIGITAL_RF_TECH_106B:
1175		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1176		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1177		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1178		break;
1179	case NFC_DIGITAL_RF_TECH_212F:
1180		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1181		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1182		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1183		break;
1184	case NFC_DIGITAL_RF_TECH_424F:
1185		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1186		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1187		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1188		break;
1189	case NFC_DIGITAL_RF_TECH_ISO15693:
1190		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1191		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1192		trf->guard_time = TRF7970A_GUARD_TIME_15693;
1193		break;
1194	default:
1195		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1196		return -EINVAL;
1197	}
1198
1199	trf->technology = tech;
1200
1201	/* If in initiator mode and not changing the RF tech due to a
1202	 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1203	 * trf7970a_init()), clear the NFC Target Detection Level register
1204	 * due to erratum.
1205	 */
1206	if (trf->iso_ctrl == 0xff)
1207		ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1208
1209	return ret;
1210}
1211
1212static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1213{
1214	int ret;
1215	u8 rssi;
1216
1217	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1218			trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
1219	if (ret)
1220		return ret;
1221
1222	ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1223	if (ret)
1224		return ret;
1225
1226	usleep_range(50, 60);
1227
1228	ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1229	if (ret)
1230		return ret;
1231
1232	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1233			trf->chip_status_ctrl);
1234	if (ret)
1235		return ret;
1236
1237	if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1238		*is_rf_field = true;
1239	else
1240		*is_rf_field = false;
1241
1242	return 0;
1243}
1244
1245static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1246{
1247	u8 iso_ctrl = trf->iso_ctrl_tech;
1248	bool is_rf_field = false;
1249	int ret;
1250
1251	dev_dbg(trf->dev, "framing: %d\n", framing);
1252
1253	switch (framing) {
1254	case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1255	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1256		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1257		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1258		break;
1259	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1260	case NFC_DIGITAL_FRAMING_NFCA_T4T:
1261	case NFC_DIGITAL_FRAMING_NFCB:
1262	case NFC_DIGITAL_FRAMING_NFCB_T4T:
1263	case NFC_DIGITAL_FRAMING_NFCF:
1264	case NFC_DIGITAL_FRAMING_NFCF_T3T:
1265	case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1266	case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1267	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1268	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1269		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1270		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1271		break;
1272	case NFC_DIGITAL_FRAMING_NFCA_T2T:
1273		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1274		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1275		break;
1276	default:
1277		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1278		return -EINVAL;
1279	}
1280
1281	trf->framing = framing;
1282
1283	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1284		ret = trf7970a_is_rf_field(trf, &is_rf_field);
1285		if (ret)
1286			return ret;
1287
1288		if (is_rf_field)
1289			return -EBUSY;
1290	}
1291
1292	if (iso_ctrl != trf->iso_ctrl) {
1293		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1294		if (ret)
1295			return ret;
1296
1297		trf->iso_ctrl = iso_ctrl;
1298
1299		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1300				trf->modulator_sys_clk_ctrl);
1301		if (ret)
1302			return ret;
1303	}
1304
1305	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1306		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1307				trf->chip_status_ctrl |
1308					TRF7970A_CHIP_STATUS_RF_ON);
1309		if (ret)
1310			return ret;
1311
1312		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1313
1314		usleep_range(trf->guard_time, trf->guard_time + 1000);
1315	}
1316
1317	return 0;
1318}
1319
1320static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1321		int param)
1322{
1323	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1324	int ret;
1325
1326	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1327
1328	mutex_lock(&trf->lock);
1329
1330	trf->is_initiator = true;
1331
1332	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1333			(trf->state == TRF7970A_ST_RF_OFF)) {
1334		ret = trf7970a_switch_rf_on(trf);
1335		if (ret)
1336			goto err_unlock;
1337	}
1338
1339	switch (type) {
1340	case NFC_DIGITAL_CONFIG_RF_TECH:
1341		ret = trf7970a_in_config_rf_tech(trf, param);
1342		break;
1343	case NFC_DIGITAL_CONFIG_FRAMING:
1344		ret = trf7970a_in_config_framing(trf, param);
1345		break;
1346	default:
1347		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1348		ret = -EINVAL;
1349	}
1350
1351err_unlock:
1352	mutex_unlock(&trf->lock);
1353	return ret;
1354}
1355
1356static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1357{
1358	switch (cmd) {
1359	case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1360	case ISO15693_CMD_LOCK_BLOCK:
1361	case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1362	case ISO15693_CMD_WRITE_AFI:
1363	case ISO15693_CMD_LOCK_AFI:
1364	case ISO15693_CMD_WRITE_DSFID:
1365	case ISO15693_CMD_LOCK_DSFID:
1366		return 1;
1367		break;
1368	default:
1369		return 0;
1370	}
1371}
1372
1373static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
1374{
1375	u8 *req = skb->data;
1376	u8 special_fcn_reg1, iso_ctrl;
1377	int ret;
1378
1379	trf->issue_eof = false;
1380
1381	/* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1382	 * special functions register 1 is cleared; otherwise, its a write or
1383	 * sector select command and '4_bit_RX' must be set.
1384	 *
1385	 * When issuing an ISO 15693 command, inspect the flags byte to see
1386	 * what speed to use.  Also, remember if the OPTION flag is set on
1387	 * a Type 5 write or lock command so the driver will know that it
1388	 * has to send an EOF in order to get a response.
1389	 */
1390	if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1391			(trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1392		if (req[0] == NFC_T2T_CMD_READ)
1393			special_fcn_reg1 = 0;
1394		else
1395			special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1396
1397		if (special_fcn_reg1 != trf->special_fcn_reg1) {
1398			ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1399					special_fcn_reg1);
1400			if (ret)
1401				return ret;
1402
1403			trf->special_fcn_reg1 = special_fcn_reg1;
1404		}
1405	} else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1406		iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1407
1408		switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1409		case 0x00:
1410			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1411			break;
1412		case ISO15693_REQ_FLAG_SUB_CARRIER:
1413			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1414			break;
1415		case ISO15693_REQ_FLAG_DATA_RATE:
1416			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1417			break;
1418		case (ISO15693_REQ_FLAG_SUB_CARRIER |
1419				ISO15693_REQ_FLAG_DATA_RATE):
1420			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1421			break;
1422		}
1423
1424		if (iso_ctrl != trf->iso_ctrl) {
1425			ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1426			if (ret)
1427				return ret;
1428
1429			trf->iso_ctrl = iso_ctrl;
1430		}
1431
1432		if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1433				trf7970a_is_iso15693_write_or_lock(req[1]) &&
1434				(req[0] & ISO15693_REQ_FLAG_OPTION))
1435			trf->issue_eof = true;
1436	}
1437
1438	return 0;
1439}
1440
1441static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1442		struct sk_buff *skb, u16 timeout,
1443		nfc_digital_cmd_complete_t cb, void *arg)
1444{
1445	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1446	u8 prefix[5];
1447	unsigned int len;
1448	int ret;
1449	u8 status;
1450
1451	dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1452			trf->state, timeout, skb->len);
1453
1454	if (skb->len > TRF7970A_TX_MAX)
1455		return -EINVAL;
1456
1457	mutex_lock(&trf->lock);
1458
1459	if ((trf->state != TRF7970A_ST_IDLE) &&
1460			(trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1461		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1462				trf->state);
1463		ret = -EIO;
1464		goto out_err;
1465	}
1466
1467	if (trf->aborting) {
1468		dev_dbg(trf->dev, "Abort process complete\n");
1469		trf->aborting = false;
1470		ret = -ECANCELED;
1471		goto out_err;
1472	}
1473
1474	if (timeout) {
1475		trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1476				GFP_KERNEL);
1477		if (!trf->rx_skb) {
1478			dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1479			ret = -ENOMEM;
1480			goto out_err;
1481		}
1482	}
1483
1484	if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1485		ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1486		if (ret)
1487			goto out_err;
1488
1489		trf->state = TRF7970A_ST_IDLE;
1490	}
1491
1492	if (trf->is_initiator) {
1493		ret = trf7970a_per_cmd_config(trf, skb);
1494		if (ret)
1495			goto out_err;
1496	}
1497
1498	trf->ddev = ddev;
1499	trf->tx_skb = skb;
1500	trf->cb = cb;
1501	trf->cb_arg = arg;
1502	trf->timeout = timeout;
1503	trf->ignore_timeout = false;
1504
1505	len = skb->len;
1506
1507	/* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1508	 * on what the current framing is, the address of the TX length byte 1
1509	 * register (0x1d), and the 2 byte length of the data to be transmitted.
1510	 * That totals 5 bytes.
1511	 */
1512	prefix[0] = TRF7970A_CMD_BIT_CTRL |
1513			TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1514	prefix[1] = TRF7970A_CMD_BIT_CTRL |
1515			TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1516	prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1517
1518	if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1519		prefix[3] = 0x00;
1520		prefix[4] = 0x0f; /* 7 bits */
1521	} else {
1522		prefix[3] = (len & 0xf00) >> 4;
1523		prefix[3] |= ((len & 0xf0) >> 4);
1524		prefix[4] = ((len & 0x0f) << 4);
1525	}
1526
1527	len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1528
1529	/* Clear possible spurious interrupt */
1530	ret = trf7970a_read_irqstatus(trf, &status);
1531	if (ret)
1532		goto out_err;
1533
1534	ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1535	if (ret) {
1536		kfree_skb(trf->rx_skb);
1537		trf->rx_skb = NULL;
1538	}
1539
1540out_err:
1541	mutex_unlock(&trf->lock);
1542	return ret;
1543}
1544
1545static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1546{
1547	int ret = 0;
1548
1549	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1550
1551	switch (tech) {
1552	case NFC_DIGITAL_RF_TECH_106A:
1553		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1554			TRF7970A_ISO_CTRL_NFC_CE |
1555			TRF7970A_ISO_CTRL_NFC_CE_14443A;
1556		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1557		break;
1558	case NFC_DIGITAL_RF_TECH_212F:
1559		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1560			TRF7970A_ISO_CTRL_NFC_NFCF_212;
1561		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1562		break;
1563	case NFC_DIGITAL_RF_TECH_424F:
1564		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1565			TRF7970A_ISO_CTRL_NFC_NFCF_424;
1566		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1567		break;
1568	default:
1569		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1570		return -EINVAL;
1571	}
1572
1573	trf->technology = tech;
1574
1575	/* Normally we write the ISO_CTRL register in
1576	 * trf7970a_tg_config_framing() because the framing can change
1577	 * the value written.  However, when sending a PSL RES,
1578	 * digital_tg_send_psl_res_complete() doesn't call
1579	 * trf7970a_tg_config_framing() so we must write the register
1580	 * here.
1581	 */
1582	if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1583			(trf->iso_ctrl_tech != trf->iso_ctrl)) {
1584		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1585				trf->iso_ctrl_tech);
1586
1587		trf->iso_ctrl = trf->iso_ctrl_tech;
1588	}
1589
1590	return ret;
1591}
1592
1593/* Since this is a target routine, several of the framing calls are
1594 * made between receiving the request and sending the response so they
1595 * should take effect until after the response is sent.  This is accomplished
1596 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1597 * handler.
1598 */
1599static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1600{
1601	u8 iso_ctrl = trf->iso_ctrl_tech;
1602	int ret;
1603
1604	dev_dbg(trf->dev, "framing: %d\n", framing);
1605
1606	switch (framing) {
1607	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1608		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1609		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1610		break;
1611	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1612	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1613	case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1614		/* These ones are applied in the interrupt handler */
1615		iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1616		break;
1617	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1618		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1619		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1620		break;
1621	case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1622		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1623		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1624		break;
1625	default:
1626		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1627		return -EINVAL;
1628	}
1629
1630	trf->framing = framing;
1631
1632	if (iso_ctrl != trf->iso_ctrl) {
1633		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1634		if (ret)
1635			return ret;
1636
1637		trf->iso_ctrl = iso_ctrl;
1638
1639		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1640				trf->modulator_sys_clk_ctrl);
1641		if (ret)
1642			return ret;
1643	}
1644
1645	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1646		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1647				trf->chip_status_ctrl |
1648					TRF7970A_CHIP_STATUS_RF_ON);
1649		if (ret)
1650			return ret;
1651
1652		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1653	}
1654
1655	return 0;
1656}
1657
1658static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1659		int param)
1660{
1661	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1662	int ret;
1663
1664	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1665
1666	mutex_lock(&trf->lock);
1667
1668	trf->is_initiator = false;
1669
1670	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1671			(trf->state == TRF7970A_ST_RF_OFF)) {
1672		ret = trf7970a_switch_rf_on(trf);
1673		if (ret)
1674			goto err_unlock;
1675	}
1676
1677	switch (type) {
1678	case NFC_DIGITAL_CONFIG_RF_TECH:
1679		ret = trf7970a_tg_config_rf_tech(trf, param);
1680		break;
1681	case NFC_DIGITAL_CONFIG_FRAMING:
1682		ret = trf7970a_tg_config_framing(trf, param);
1683		break;
1684	default:
1685		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1686		ret = -EINVAL;
1687	}
1688
1689err_unlock:
1690	mutex_unlock(&trf->lock);
1691	return ret;
1692}
1693
1694static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1695		nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
1696{
1697	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1698	int ret;
1699
1700	mutex_lock(&trf->lock);
1701
1702	if ((trf->state != TRF7970A_ST_IDLE) &&
1703			(trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1704		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1705				trf->state);
1706		ret = -EIO;
1707		goto out_err;
1708	}
1709
1710	if (trf->aborting) {
1711		dev_dbg(trf->dev, "Abort process complete\n");
1712		trf->aborting = false;
1713		ret = -ECANCELED;
1714		goto out_err;
1715	}
1716
1717	trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1718			GFP_KERNEL);
1719	if (!trf->rx_skb) {
1720		dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1721		ret = -ENOMEM;
1722		goto out_err;
1723	}
1724
1725	ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1726			TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1727			TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1728			TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1729			TRF7970A_RX_SPECIAL_SETTINGS_C212);
1730	if (ret)
1731		goto out_err;
1732
1733	ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1734			TRF7970A_REG_IO_CTRL_VRS(0x1));
1735	if (ret)
1736		goto out_err;
1737
1738	ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1739			TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1740	if (ret)
1741		goto out_err;
1742
1743	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1744			TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1745	if (ret)
1746		goto out_err;
1747
1748	trf->ddev = ddev;
1749	trf->cb = cb;
1750	trf->cb_arg = arg;
1751	trf->timeout = timeout;
1752	trf->ignore_timeout = false;
1753
1754	ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1755	if (ret)
1756		goto out_err;
1757
1758	trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1759				   TRF7970A_ST_LISTENING;
1760
1761	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1762
1763out_err:
1764	mutex_unlock(&trf->lock);
1765	return ret;
1766}
1767
1768static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1769		nfc_digital_cmd_complete_t cb, void *arg)
1770{
1771	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1772
1773	dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1774			trf->state, timeout);
1775
1776	return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1777}
1778
1779static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1780		u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1781{
1782	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1783	int ret;
1784
1785	dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1786			trf->state, timeout);
1787
1788	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1789			NFC_DIGITAL_RF_TECH_106A);
1790	if (ret)
1791		return ret;
1792
1793	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1794			NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1795	if (ret)
1796		return ret;
1797
1798	return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1799}
1800
1801static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1802{
1803	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1804
1805	dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1806			trf->state, trf->md_rf_tech);
1807
1808	*rf_tech = trf->md_rf_tech;
1809
1810	return 0;
1811}
1812
1813static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1814{
1815	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1816
1817	dev_dbg(trf->dev, "Abort process initiated\n");
1818
1819	mutex_lock(&trf->lock);
1820
1821	switch (trf->state) {
1822	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1823	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1824	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1825	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1826		trf->aborting = true;
1827		break;
1828	case TRF7970A_ST_LISTENING:
1829		trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1830		trf7970a_send_err_upstream(trf, -ECANCELED);
1831		dev_dbg(trf->dev, "Abort process complete\n");
1832		break;
1833	default:
1834		break;
1835	}
1836
1837	mutex_unlock(&trf->lock);
1838}
1839
1840static struct nfc_digital_ops trf7970a_nfc_ops = {
1841	.in_configure_hw	= trf7970a_in_configure_hw,
1842	.in_send_cmd		= trf7970a_send_cmd,
1843	.tg_configure_hw	= trf7970a_tg_configure_hw,
1844	.tg_send_cmd		= trf7970a_send_cmd,
1845	.tg_listen		= trf7970a_tg_listen,
1846	.tg_listen_md		= trf7970a_tg_listen_md,
1847	.tg_get_rf_tech		= trf7970a_tg_get_rf_tech,
1848	.switch_rf		= trf7970a_switch_rf,
1849	.abort_cmd		= trf7970a_abort_cmd,
1850};
1851
1852static int trf7970a_power_up(struct trf7970a *trf)
1853{
1854	int ret;
1855
1856	dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1857
1858	if (trf->state != TRF7970A_ST_PWR_OFF)
1859		return 0;
1860
1861	ret = regulator_enable(trf->regulator);
1862	if (ret) {
1863		dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1864		return ret;
1865	}
1866
1867	usleep_range(5000, 6000);
1868
1869	if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1870		gpio_set_value(trf->en2_gpio, 1);
1871		usleep_range(1000, 2000);
1872	}
1873
1874	gpio_set_value(trf->en_gpio, 1);
1875
1876	usleep_range(20000, 21000);
1877
1878	trf->state = TRF7970A_ST_RF_OFF;
1879
1880	return 0;
1881}
1882
1883static int trf7970a_power_down(struct trf7970a *trf)
1884{
1885	int ret;
1886
1887	dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1888
1889	if (trf->state == TRF7970A_ST_PWR_OFF)
1890		return 0;
1891
1892	if (trf->state != TRF7970A_ST_RF_OFF) {
1893		dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1894				trf->state);
1895		return -EBUSY;
1896	}
1897
1898	gpio_set_value(trf->en_gpio, 0);
1899	gpio_set_value(trf->en2_gpio, 0);
1900
1901	ret = regulator_disable(trf->regulator);
1902	if (ret)
1903		dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1904				ret);
1905
1906	trf->state = TRF7970A_ST_PWR_OFF;
1907
1908	return ret;
1909}
1910
1911static int trf7970a_startup(struct trf7970a *trf)
1912{
1913	int ret;
1914
1915	ret = trf7970a_power_up(trf);
1916	if (ret)
1917		return ret;
1918
1919	pm_runtime_set_active(trf->dev);
1920	pm_runtime_enable(trf->dev);
1921	pm_runtime_mark_last_busy(trf->dev);
1922
1923	return 0;
1924}
1925
1926static void trf7970a_shutdown(struct trf7970a *trf)
1927{
1928	switch (trf->state) {
1929	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1930	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1931	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1932	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1933	case TRF7970A_ST_LISTENING:
1934		trf7970a_send_err_upstream(trf, -ECANCELED);
1935		/* FALLTHROUGH */
1936	case TRF7970A_ST_IDLE:
1937	case TRF7970A_ST_IDLE_RX_BLOCKED:
1938		trf7970a_switch_rf_off(trf);
1939		break;
1940	default:
1941		break;
1942	}
1943
1944	pm_runtime_disable(trf->dev);
1945	pm_runtime_set_suspended(trf->dev);
1946
1947	trf7970a_power_down(trf);
1948}
1949
1950static int trf7970a_get_autosuspend_delay(struct device_node *np)
1951{
1952	int autosuspend_delay, ret;
1953
1954	ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1955	if (ret)
1956		autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1957
1958	return autosuspend_delay;
1959}
1960
1961static int trf7970a_get_vin_voltage_override(struct device_node *np,
1962		u32 *vin_uvolts)
1963{
1964	return of_property_read_u32(np, "vin-voltage-override", vin_uvolts);
1965}
1966
1967static int trf7970a_probe(struct spi_device *spi)
1968{
1969	struct device_node *np = spi->dev.of_node;
1970	struct trf7970a *trf;
1971	int uvolts, autosuspend_delay, ret;
1972
1973	if (!np) {
1974		dev_err(&spi->dev, "No Device Tree entry\n");
1975		return -EINVAL;
1976	}
1977
1978	trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
1979	if (!trf)
1980		return -ENOMEM;
1981
1982	trf->state = TRF7970A_ST_PWR_OFF;
1983	trf->dev = &spi->dev;
1984	trf->spi = spi;
1985
1986	spi->mode = SPI_MODE_1;
1987	spi->bits_per_word = 8;
1988
1989	ret = spi_setup(spi);
1990	if (ret < 0) {
1991		dev_err(trf->dev, "Can't set up SPI Communication\n");
1992		return ret;
1993	}
1994
1995	if (of_property_read_bool(np, "irq-status-read-quirk"))
1996		trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
1997
1998	/* There are two enable pins - both must be present */
1999	trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
2000	if (!gpio_is_valid(trf->en_gpio)) {
2001		dev_err(trf->dev, "No EN GPIO property\n");
2002		return trf->en_gpio;
2003	}
2004
2005	ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
2006			GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN");
2007	if (ret) {
2008		dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
2009		return ret;
2010	}
2011
2012	trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
2013	if (!gpio_is_valid(trf->en2_gpio)) {
2014		dev_err(trf->dev, "No EN2 GPIO property\n");
2015		return trf->en2_gpio;
2016	}
2017
2018	ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
2019			GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
2020	if (ret) {
2021		dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
2022		return ret;
2023	}
2024
2025	if (of_property_read_bool(np, "en2-rf-quirk"))
2026		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2027
2028	ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2029			trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2030			"trf7970a", trf);
2031	if (ret) {
2032		dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2033		return ret;
2034	}
2035
2036	mutex_init(&trf->lock);
2037	INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2038
2039	trf->regulator = devm_regulator_get(&spi->dev, "vin");
2040	if (IS_ERR(trf->regulator)) {
2041		ret = PTR_ERR(trf->regulator);
2042		dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2043		goto err_destroy_lock;
2044	}
2045
2046	ret = regulator_enable(trf->regulator);
2047	if (ret) {
2048		dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2049		goto err_destroy_lock;
2050	}
2051
2052	ret = trf7970a_get_vin_voltage_override(np, &uvolts);
2053	if (ret)
2054		uvolts = regulator_get_voltage(trf->regulator);
2055
2056	if (uvolts > 4000000)
2057		trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2058
2059	trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2060			TRF7970A_SUPPORTED_PROTOCOLS,
2061			NFC_DIGITAL_DRV_CAPS_IN_CRC |
2062				NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
2063	if (!trf->ddev) {
2064		dev_err(trf->dev, "Can't allocate NFC digital device\n");
2065		ret = -ENOMEM;
2066		goto err_disable_regulator;
2067	}
2068
2069	nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2070	nfc_digital_set_drvdata(trf->ddev, trf);
2071	spi_set_drvdata(spi, trf);
2072
2073	autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2074
2075	pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2076	pm_runtime_use_autosuspend(trf->dev);
2077
2078	ret = trf7970a_startup(trf);
2079	if (ret)
2080		goto err_free_ddev;
2081
2082	ret = nfc_digital_register_device(trf->ddev);
2083	if (ret) {
2084		dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2085				ret);
2086		goto err_shutdown;
2087	}
2088
2089	return 0;
2090
2091err_shutdown:
2092	trf7970a_shutdown(trf);
2093err_free_ddev:
2094	nfc_digital_free_device(trf->ddev);
2095err_disable_regulator:
2096	regulator_disable(trf->regulator);
2097err_destroy_lock:
2098	mutex_destroy(&trf->lock);
2099	return ret;
2100}
2101
2102static int trf7970a_remove(struct spi_device *spi)
2103{
2104	struct trf7970a *trf = spi_get_drvdata(spi);
2105
2106	mutex_lock(&trf->lock);
2107
2108	trf7970a_shutdown(trf);
2109
2110	mutex_unlock(&trf->lock);
2111
2112	nfc_digital_unregister_device(trf->ddev);
2113	nfc_digital_free_device(trf->ddev);
2114
2115	regulator_disable(trf->regulator);
2116
2117	mutex_destroy(&trf->lock);
2118
2119	return 0;
2120}
2121
2122#ifdef CONFIG_PM_SLEEP
2123static int trf7970a_suspend(struct device *dev)
2124{
2125	struct spi_device *spi = container_of(dev, struct spi_device, dev);
2126	struct trf7970a *trf = spi_get_drvdata(spi);
2127
2128	dev_dbg(dev, "Suspend\n");
2129
2130	mutex_lock(&trf->lock);
2131
2132	trf7970a_shutdown(trf);
2133
2134	mutex_unlock(&trf->lock);
2135
2136	return 0;
2137}
2138
2139static int trf7970a_resume(struct device *dev)
2140{
2141	struct spi_device *spi = container_of(dev, struct spi_device, dev);
2142	struct trf7970a *trf = spi_get_drvdata(spi);
2143	int ret;
2144
2145	dev_dbg(dev, "Resume\n");
2146
2147	mutex_lock(&trf->lock);
2148
2149	ret = trf7970a_startup(trf);
2150
2151	mutex_unlock(&trf->lock);
2152
2153	return ret;
2154}
2155#endif
2156
2157#ifdef CONFIG_PM_RUNTIME
2158static int trf7970a_pm_runtime_suspend(struct device *dev)
2159{
2160	struct spi_device *spi = container_of(dev, struct spi_device, dev);
2161	struct trf7970a *trf = spi_get_drvdata(spi);
2162	int ret;
2163
2164	dev_dbg(dev, "Runtime suspend\n");
2165
2166	mutex_lock(&trf->lock);
2167
2168	ret = trf7970a_power_down(trf);
2169
2170	mutex_unlock(&trf->lock);
2171
2172	return ret;
2173}
2174
2175static int trf7970a_pm_runtime_resume(struct device *dev)
2176{
2177	struct spi_device *spi = container_of(dev, struct spi_device, dev);
2178	struct trf7970a *trf = spi_get_drvdata(spi);
2179	int ret;
2180
2181	dev_dbg(dev, "Runtime resume\n");
2182
2183	ret = trf7970a_power_up(trf);
2184	if (!ret)
2185		pm_runtime_mark_last_busy(dev);
2186
2187	return ret;
2188}
2189#endif
2190
2191static const struct dev_pm_ops trf7970a_pm_ops = {
2192	SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2193	SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2194			trf7970a_pm_runtime_resume, NULL)
2195};
2196
2197static const struct spi_device_id trf7970a_id_table[] = {
2198	{ "trf7970a", 0 },
2199	{ }
2200};
2201MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2202
2203static struct spi_driver trf7970a_spi_driver = {
2204	.probe		= trf7970a_probe,
2205	.remove		= trf7970a_remove,
2206	.id_table	= trf7970a_id_table,
2207	.driver		= {
2208		.name	= "trf7970a",
2209		.owner	= THIS_MODULE,
2210		.pm	= &trf7970a_pm_ops,
2211	},
2212};
2213
2214module_spi_driver(trf7970a_spi_driver);
2215
2216MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2217MODULE_LICENSE("GPL v2");
2218MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");
2219