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authorMark A. Greer <mgreer@animalcreek.com>2014-03-10 14:56:22 -0400
committerSamuel Ortiz <sameo@linux.intel.com>2014-03-10 19:46:55 -0400
commit165063f1dac43e48ceb907490fff0a8413b9a32d (patch)
tree36d7f1a45e71872b9030c288d2a4990961d521ea /drivers/nfc
parentceeee42d85b4c91b16b6019e69c584589b72be04 (diff)
NFC: trf7970a: Add driver with ISO/IEC 14443 Type 2 Tag Support
Add a driver for the Texas Instruments TRF7970a RFID/NFC/15693 transceiver. The driver currently supports ISO/IEC 14443 Type 2 tags only (MIFARE Ultralight and Ultralight C but not Classic). CC: Erick Macias <emacias@ti.com> CC: Felipe Balbi <balbi@ti.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/nfc')
-rw-r--r--drivers/nfc/Kconfig12
-rw-r--r--drivers/nfc/Makefile1
-rw-r--r--drivers/nfc/trf7970a.c1224
3 files changed, 1237 insertions, 0 deletions
diff --git a/drivers/nfc/Kconfig b/drivers/nfc/Kconfig
index fe20e1cc0545..65d4ca19d132 100644
--- a/drivers/nfc/Kconfig
+++ b/drivers/nfc/Kconfig
@@ -26,6 +26,18 @@ config NFC_WILINK
26 Say Y here to compile support for Texas Instrument's NFC WiLink driver 26 Say Y here to compile support for Texas Instrument's NFC WiLink driver
27 into the kernel or say M to compile it as module. 27 into the kernel or say M to compile it as module.
28 28
29config NFC_TRF7970A
30 tristate "Texas Instruments TRF7970a NFC driver"
31 depends on SPI && NFC_DIGITAL
32 help
33 This option enables the NFC driver for Texas Instruments' TRF7970a
34 device. Such device supports 5 different protocols: ISO14443A,
35 ISO14443B, FeLiCa, ISO15693 and ISO18000-3.
36
37 Say Y here to compile support for TRF7970a into the kernel or
38 say M to compile it as a module. The module will be called
39 trf7970a.ko.
40
29config NFC_MEI_PHY 41config NFC_MEI_PHY
30 tristate "MEI bus NFC device support" 42 tristate "MEI bus NFC device support"
31 depends on INTEL_MEI && NFC_HCI 43 depends on INTEL_MEI && NFC_HCI
diff --git a/drivers/nfc/Makefile b/drivers/nfc/Makefile
index 56ab822ba03d..ae42a3fa60c9 100644
--- a/drivers/nfc/Makefile
+++ b/drivers/nfc/Makefile
@@ -10,5 +10,6 @@ obj-$(CONFIG_NFC_MEI_PHY) += mei_phy.o
10obj-$(CONFIG_NFC_SIM) += nfcsim.o 10obj-$(CONFIG_NFC_SIM) += nfcsim.o
11obj-$(CONFIG_NFC_PORT100) += port100.o 11obj-$(CONFIG_NFC_PORT100) += port100.o
12obj-$(CONFIG_NFC_MRVL) += nfcmrvl/ 12obj-$(CONFIG_NFC_MRVL) += nfcmrvl/
13obj-$(CONFIG_NFC_TRF7970A) += trf7970a.o
13 14
14ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG 15ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
new file mode 100644
index 000000000000..0d62d45d6884
--- /dev/null
+++ b/drivers/nfc/trf7970a.c
@@ -0,0 +1,1224 @@
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/nfc.h>
20#include <linux/skbuff.h>
21#include <linux/delay.h>
22#include <linux/gpio.h>
23#include <linux/of.h>
24#include <linux/of_gpio.h>
25#include <linux/spi/spi.h>
26#include <linux/regulator/consumer.h>
27
28#include <net/nfc/nfc.h>
29#include <net/nfc/digital.h>
30
31/* There are 3 ways the host can communicate with the trf7970a:
32 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
33 * SS mode. The driver only supports the two SPI modes.
34 *
35 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
36 * pins must asserted in that order and with specific delays in between.
37 * The delays used in the driver were provided by TI and have been
38 * confirmed to work with this driver.
39 *
40 * Timeouts are implemented using the delayed workqueue kernel facility.
41 * Timeouts are required so things don't hang when there is no response
42 * from the trf7970a (or tag). Using this mechanism creates a race with
43 * interrupts, however. That is, an interrupt and a timeout could occur
44 * closely enough together that one is blocked by the mutex while the other
45 * executes. When the timeout handler executes first and blocks the
46 * interrupt handler, it will eventually set the state to IDLE so the
47 * interrupt handler will check the state and exit with no harm done.
48 * When the interrupt handler executes first and blocks the timeout handler,
49 * the cancel_delayed_work() call will know that it didn't cancel the
50 * work item (i.e., timeout) and will return zero. That return code is
51 * used by the timer handler to indicate that it should ignore the timeout
52 * once its unblocked.
53 *
54 * Aborting an active command isn't as simple as it seems because the only
55 * way to abort a command that's already been sent to the tag is so turn
56 * off power to the tag. If we do that, though, we'd have to go through
57 * the entire anticollision procedure again but the digital layer doesn't
58 * support that. So, if an abort is received before trf7970a_in_send_cmd()
59 * has sent the command to the tag, it simply returns -ECANCELED. If the
60 * command has already been sent to the tag, then the driver continues
61 * normally and recieves the response data (or error) but just before
62 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
63 * upstream instead. If the command failed, that error will be sent
64 * upstream.
65 *
66 * When recieving data from a tag and the interrupt status register has
67 * only the SRX bit set, it means that all of the data has been received
68 * (once what's in the fifo has been read). However, depending on timing
69 * an interrupt status with only the SRX bit set may not be recived. In
70 * those cases, the timeout mechanism is used to wait 5 ms in case more
71 * data arrives. After 5 ms, it is assumed that all of the data has been
72 * received and the accumulated rx data is sent upstream. The
73 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
74 * (i.e., it indicates that some data has been received but we're not sure
75 * if there is more coming so a timeout in this state means all data has
76 * been received and there isn't an error). The delay is 5 ms since delays
77 * over 2 ms have been observed during testing (a little extra just in case).
78 *
79 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
80 * Having only 4 bits in the FIFO won't normally generate an interrupt so
81 * driver enables the '4_bit_RX' bit of the Special Functions register 1
82 * to cause an interrupt in that case. Leaving that bit for a read command
83 * messes up the data returned so it is only enabled when the framing is
84 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
85 * Unfortunately, that means that the driver has to peek into tx frames
86 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'. This is done by
87 * the trf7970a_per_cmd_config() routine.
88 */
89
90#define TRF7970A_SUPPORTED_PROTOCOLS NFC_PROTO_MIFARE_MASK
91
92/* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
93 * on what the current framing is, the address of the TX length byte 1
94 * register (0x1d), and the 2 byte length of the data to be transmitted.
95 * That totals 5 bytes.
96 */
97#define TRF7970A_TX_SKB_HEADROOM 5
98
99#define TRF7970A_RX_SKB_ALLOC_SIZE 256
100
101#define TRF7970A_FIFO_SIZE 128
102
103/* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
104#define TRF7970A_TX_MAX (4096 - 1)
105
106#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT 5
107#define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT 3
108
109/* Quirks */
110/* Erratum: When reading IRQ Status register on trf7970a, we must issue a
111 * read continuous command for IRQ Status and Collision Position registers.
112 */
113#define TRF7970A_QUIRK_IRQ_STATUS_READ_ERRATA BIT(0)
114
115/* Direct commands */
116#define TRF7970A_CMD_IDLE 0x00
117#define TRF7970A_CMD_SOFT_INIT 0x03
118#define TRF7970A_CMD_RF_COLLISION 0x04
119#define TRF7970A_CMD_RF_COLLISION_RESPONSE_N 0x05
120#define TRF7970A_CMD_RF_COLLISION_RESPONSE_0 0x06
121#define TRF7970A_CMD_FIFO_RESET 0x0f
122#define TRF7970A_CMD_TRANSMIT_NO_CRC 0x10
123#define TRF7970A_CMD_TRANSMIT 0x11
124#define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC 0x12
125#define TRF7970A_CMD_DELAY_TRANSMIT 0x13
126#define TRF7970A_CMD_EOF 0x14
127#define TRF7970A_CMD_CLOSE_SLOT 0x15
128#define TRF7970A_CMD_BLOCK_RX 0x16
129#define TRF7970A_CMD_ENABLE_RX 0x17
130#define TRF7970A_CMD_TEST_EXT_RF 0x18
131#define TRF7970A_CMD_TEST_INT_RF 0x19
132#define TRF7970A_CMD_RX_GAIN_ADJUST 0x1a
133
134/* Bits determining whether its a direct command or register R/W,
135 * whether to use a continuous SPI transaction or not, and the actual
136 * direct cmd opcode or regster address.
137 */
138#define TRF7970A_CMD_BIT_CTRL BIT(7)
139#define TRF7970A_CMD_BIT_RW BIT(6)
140#define TRF7970A_CMD_BIT_CONTINUOUS BIT(5)
141#define TRF7970A_CMD_BIT_OPCODE(opcode) ((opcode) & 0x1f)
142
143/* Registers addresses */
144#define TRF7970A_CHIP_STATUS_CTRL 0x00
145#define TRF7970A_ISO_CTRL 0x01
146#define TRF7970A_ISO14443B_TX_OPTIONS 0x02
147#define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
148#define TRF7970A_TX_TIMER_SETTING_H_BYTE 0x04
149#define TRF7970A_TX_TIMER_SETTING_L_BYTE 0x05
150#define TRF7970A_TX_PULSE_LENGTH_CTRL 0x06
151#define TRF7970A_RX_NO_RESPONSE_WAIT 0x07
152#define TRF7970A_RX_WAIT_TIME 0x08
153#define TRF7970A_MODULATOR_SYS_CLK_CTRL 0x09
154#define TRF7970A_RX_SPECIAL_SETTINGS 0x0a
155#define TRF7970A_REG_IO_CTRL 0x0b
156#define TRF7970A_IRQ_STATUS 0x0c
157#define TRF7970A_COLLISION_IRQ_MASK 0x0d
158#define TRF7970A_COLLISION_POSITION 0x0e
159#define TRF7970A_RSSI_OSC_STATUS 0x0f
160#define TRF7970A_SPECIAL_FCN_REG1 0x10
161#define TRF7970A_SPECIAL_FCN_REG2 0x11
162#define TRF7970A_RAM1 0x12
163#define TRF7970A_RAM2 0x13
164#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS 0x14
165#define TRF7970A_NFC_LOW_FIELD_LEVEL 0x16
166#define TRF7970A_NFCID1 0x17
167#define TRF7970A_NFC_TARGET_LEVEL 0x18
168#define TRF79070A_NFC_TARGET_PROTOCOL 0x19
169#define TRF7970A_TEST_REGISTER1 0x1a
170#define TRF7970A_TEST_REGISTER2 0x1b
171#define TRF7970A_FIFO_STATUS 0x1c
172#define TRF7970A_TX_LENGTH_BYTE1 0x1d
173#define TRF7970A_TX_LENGTH_BYTE2 0x1e
174#define TRF7970A_FIFO_IO_REGISTER 0x1f
175
176/* Chip Status Control Register Bits */
177#define TRF7970A_CHIP_STATUS_VRS5_3 BIT(0)
178#define TRF7970A_CHIP_STATUS_REC_ON BIT(1)
179#define TRF7970A_CHIP_STATUS_AGC_ON BIT(2)
180#define TRF7970A_CHIP_STATUS_PM_ON BIT(3)
181#define TRF7970A_CHIP_STATUS_RF_PWR BIT(4)
182#define TRF7970A_CHIP_STATUS_RF_ON BIT(5)
183#define TRF7970A_CHIP_STATUS_DIRECT BIT(6)
184#define TRF7970A_CHIP_STATUS_STBY BIT(7)
185
186/* ISO Control Register Bits */
187#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662 0x00
188#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662 0x01
189#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648 0x02
190#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
191#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a 0x04
192#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667 0x05
193#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669 0x06
194#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
195#define TRF7970A_ISO_CTRL_14443A_106 0x08
196#define TRF7970A_ISO_CTRL_14443A_212 0x09
197#define TRF7970A_ISO_CTRL_14443A_424 0x0a
198#define TRF7970A_ISO_CTRL_14443A_848 0x0b
199#define TRF7970A_ISO_CTRL_14443B_106 0x0c
200#define TRF7970A_ISO_CTRL_14443B_212 0x0d
201#define TRF7970A_ISO_CTRL_14443B_424 0x0e
202#define TRF7970A_ISO_CTRL_14443B_848 0x0f
203#define TRF7970A_ISO_CTRL_FELICA_212 0x1a
204#define TRF7970A_ISO_CTRL_FELICA_424 0x1b
205#define TRF7970A_ISO_CTRL_RFID BIT(5)
206#define TRF7970A_ISO_CTRL_DIR_MODE BIT(6)
207#define TRF7970A_ISO_CTRL_RX_CRC_N BIT(7) /* true == No CRC */
208
209#define TRF7970A_ISO_CTRL_RFID_SPEED_MASK 0x1f
210
211/* Modulator and SYS_CLK Control Register Bits */
212#define TRF7970A_MODULATOR_DEPTH(n) ((n) & 0x7)
213#define TRF7970A_MODULATOR_DEPTH_ASK10 (TRF7970A_MODULATOR_DEPTH(0))
214#define TRF7970A_MODULATOR_DEPTH_OOK (TRF7970A_MODULATOR_DEPTH(1))
215#define TRF7970A_MODULATOR_DEPTH_ASK7 (TRF7970A_MODULATOR_DEPTH(2))
216#define TRF7970A_MODULATOR_DEPTH_ASK8_5 (TRF7970A_MODULATOR_DEPTH(3))
217#define TRF7970A_MODULATOR_DEPTH_ASK13 (TRF7970A_MODULATOR_DEPTH(4))
218#define TRF7970A_MODULATOR_DEPTH_ASK16 (TRF7970A_MODULATOR_DEPTH(5))
219#define TRF7970A_MODULATOR_DEPTH_ASK22 (TRF7970A_MODULATOR_DEPTH(6))
220#define TRF7970A_MODULATOR_DEPTH_ASK30 (TRF7970A_MODULATOR_DEPTH(7))
221#define TRF7970A_MODULATOR_EN_ANA BIT(3)
222#define TRF7970A_MODULATOR_CLK(n) (((n) & 0x3) << 4)
223#define TRF7970A_MODULATOR_CLK_DISABLED (TRF7970A_MODULATOR_CLK(0))
224#define TRF7970A_MODULATOR_CLK_3_6 (TRF7970A_MODULATOR_CLK(1))
225#define TRF7970A_MODULATOR_CLK_6_13 (TRF7970A_MODULATOR_CLK(2))
226#define TRF7970A_MODULATOR_CLK_13_27 (TRF7970A_MODULATOR_CLK(3))
227#define TRF7970A_MODULATOR_EN_OOK BIT(6)
228#define TRF7970A_MODULATOR_27MHZ BIT(7)
229
230/* IRQ Status Register Bits */
231#define TRF7970A_IRQ_STATUS_NORESP BIT(0) /* ISO15693 only */
232#define TRF7970A_IRQ_STATUS_COL BIT(1)
233#define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR BIT(2)
234#define TRF7970A_IRQ_STATUS_PARITY_ERROR BIT(3)
235#define TRF7970A_IRQ_STATUS_CRC_ERROR BIT(4)
236#define TRF7970A_IRQ_STATUS_FIFO BIT(5)
237#define TRF7970A_IRQ_STATUS_SRX BIT(6)
238#define TRF7970A_IRQ_STATUS_TX BIT(7)
239
240#define TRF7970A_IRQ_STATUS_ERROR \
241 (TRF7970A_IRQ_STATUS_COL | \
242 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR | \
243 TRF7970A_IRQ_STATUS_PARITY_ERROR | \
244 TRF7970A_IRQ_STATUS_CRC_ERROR)
245
246#define TRF7970A_SPECIAL_FCN_REG1_COL_7_6 BIT(0)
247#define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL BIT(1)
248#define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX BIT(2)
249#define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE BIT(3)
250#define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US BIT(4)
251#define TRF7970A_SPECIAL_FCN_REG1_PAR43 BIT(5)
252
253#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124 (0x0 << 2)
254#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120 (0x1 << 2)
255#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112 (0x2 << 2)
256#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 (0x3 << 2)
257#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4 0x0
258#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8 0x1
259#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16 0x2
260#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32 0x3
261
262#define TRF7970A_FIFO_STATUS_OVERFLOW BIT(7)
263
264/* NFC (ISO/IEC 14443A) Type 2 Tag commands */
265#define NFC_T2T_CMD_READ 0x30
266
267enum trf7970a_state {
268 TRF7970A_ST_OFF,
269 TRF7970A_ST_IDLE,
270 TRF7970A_ST_IDLE_RX_BLOCKED,
271 TRF7970A_ST_WAIT_FOR_TX_FIFO,
272 TRF7970A_ST_WAIT_FOR_RX_DATA,
273 TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
274 TRF7970A_ST_MAX
275};
276
277struct trf7970a {
278 enum trf7970a_state state;
279 struct device *dev;
280 struct spi_device *spi;
281 struct regulator *regulator;
282 struct nfc_digital_dev *ddev;
283 u32 quirks;
284 bool powering_up;
285 bool aborting;
286 struct sk_buff *tx_skb;
287 struct sk_buff *rx_skb;
288 nfc_digital_cmd_complete_t cb;
289 void *cb_arg;
290 u8 iso_ctrl;
291 u8 special_fcn_reg1;
292 int technology;
293 int framing;
294 u8 tx_cmd;
295 int en2_gpio;
296 int en_gpio;
297 struct mutex lock;
298 unsigned int timeout;
299 bool ignore_timeout;
300 struct delayed_work timeout_work;
301};
302
303
304static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
305{
306 u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
307 int ret;
308
309 dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
310
311 ret = spi_write(trf->spi, &cmd, 1);
312 if (ret)
313 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
314 ret);
315 return ret;
316}
317
318static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
319{
320 u8 addr = TRF7970A_CMD_BIT_RW | reg;
321 int ret;
322
323 ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
324 if (ret)
325 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
326 ret);
327
328 dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
329
330 return ret;
331}
332
333static int trf7970a_read_cont(struct trf7970a *trf, u8 reg,
334 u8 *buf, size_t len)
335{
336 u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
337 int ret;
338
339 dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
340
341 ret = spi_write_then_read(trf->spi, &addr, 1, buf, len);
342 if (ret)
343 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
344 ret);
345 return ret;
346}
347
348static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
349{
350 u8 buf[2] = { reg, val };
351 int ret;
352
353 dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
354
355 ret = spi_write(trf->spi, buf, 2);
356 if (ret)
357 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
358 buf[0], buf[1], ret);
359
360 return ret;
361}
362
363static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
364{
365 int ret;
366 u8 buf[2];
367 u8 addr;
368
369 addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
370
371 if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ_ERRATA) {
372 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
373 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
374 } else {
375 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
376 }
377
378 if (ret)
379 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
380 __func__, ret);
381 else
382 *status = buf[0];
383
384 return ret;
385}
386
387static void trf7970a_send_upstream(struct trf7970a *trf)
388{
389 u8 rssi;
390
391 dev_kfree_skb_any(trf->tx_skb);
392 trf->tx_skb = NULL;
393
394 if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
395 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
396 16, 1, trf->rx_skb->data, trf->rx_skb->len,
397 false);
398
399 /* According to the manual it is "good form" to reset the fifo and
400 * read the RSSI levels & oscillator status register here. It doesn't
401 * explain why.
402 */
403 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
404 trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
405
406 trf->state = TRF7970A_ST_IDLE;
407
408 if (trf->aborting) {
409 dev_dbg(trf->dev, "Abort process complete\n");
410
411 if (!IS_ERR(trf->rx_skb)) {
412 kfree_skb(trf->rx_skb);
413 trf->rx_skb = ERR_PTR(-ECANCELED);
414 }
415
416 trf->aborting = false;
417 }
418
419 trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
420
421 trf->rx_skb = NULL;
422}
423
424static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
425{
426 dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
427
428 kfree_skb(trf->rx_skb);
429 trf->rx_skb = ERR_PTR(errno);
430
431 trf7970a_send_upstream(trf);
432}
433
434static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
435 unsigned int len)
436{
437 unsigned int timeout;
438 int ret;
439
440 print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
441 16, 1, skb->data, len, false);
442
443 ret = spi_write(trf->spi, skb->data, len);
444 if (ret) {
445 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
446 ret);
447 return ret;
448 }
449
450 skb_pull(skb, len);
451
452 if (skb->len > 0) {
453 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
454 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
455 } else {
456 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
457 timeout = trf->timeout;
458 }
459
460 dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
461 trf->state);
462
463 schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
464
465 return 0;
466}
467
468static void trf7970a_fill_fifo(struct trf7970a *trf)
469{
470 struct sk_buff *skb = trf->tx_skb;
471 unsigned int len;
472 int ret;
473 u8 fifo_bytes;
474
475 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
476 if (ret) {
477 trf7970a_send_err_upstream(trf, ret);
478 return;
479 }
480
481 dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
482
483 if (fifo_bytes & TRF7970A_FIFO_STATUS_OVERFLOW) {
484 dev_err(trf->dev, "%s - fifo overflow: 0x%x\n", __func__,
485 fifo_bytes);
486 trf7970a_send_err_upstream(trf, -EIO);
487 return;
488 }
489
490 /* Calculate how much more data can be written to the fifo */
491 len = TRF7970A_FIFO_SIZE - fifo_bytes;
492 len = min(skb->len, len);
493
494 ret = trf7970a_transmit(trf, skb, len);
495 if (ret)
496 trf7970a_send_err_upstream(trf, ret);
497}
498
499static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
500{
501 struct sk_buff *skb = trf->rx_skb;
502 int ret;
503 u8 fifo_bytes;
504
505 if (status & TRF7970A_IRQ_STATUS_ERROR) {
506 trf7970a_send_err_upstream(trf, -EIO);
507 return;
508 }
509
510 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
511 if (ret) {
512 trf7970a_send_err_upstream(trf, ret);
513 return;
514 }
515
516 dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
517
518 if (!fifo_bytes)
519 goto no_rx_data;
520
521 if (fifo_bytes & TRF7970A_FIFO_STATUS_OVERFLOW) {
522 dev_err(trf->dev, "%s - fifo overflow: 0x%x\n", __func__,
523 fifo_bytes);
524 trf7970a_send_err_upstream(trf, -EIO);
525 return;
526 }
527
528 if (fifo_bytes > skb_tailroom(skb)) {
529 skb = skb_copy_expand(skb, skb_headroom(skb),
530 max_t(int, fifo_bytes,
531 TRF7970A_RX_SKB_ALLOC_SIZE),
532 GFP_KERNEL);
533 if (!skb) {
534 trf7970a_send_err_upstream(trf, -ENOMEM);
535 return;
536 }
537
538 kfree_skb(trf->rx_skb);
539 trf->rx_skb = skb;
540 }
541
542 ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
543 skb_put(skb, fifo_bytes), fifo_bytes);
544 if (ret) {
545 trf7970a_send_err_upstream(trf, ret);
546 return;
547 }
548
549 /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
550 if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
551 (trf->special_fcn_reg1 ==
552 TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
553 skb->data[0] >>= 4;
554 status = TRF7970A_IRQ_STATUS_SRX;
555 } else {
556 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
557 }
558
559no_rx_data:
560 if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
561 trf7970a_send_upstream(trf);
562 return;
563 }
564
565 dev_dbg(trf->dev, "Setting timeout for %d ms\n",
566 TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
567
568 schedule_delayed_work(&trf->timeout_work,
569 msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
570}
571
572static irqreturn_t trf7970a_irq(int irq, void *dev_id)
573{
574 struct trf7970a *trf = dev_id;
575 int ret;
576 u8 status;
577
578 mutex_lock(&trf->lock);
579
580 if (trf->state == TRF7970A_ST_OFF) {
581 mutex_unlock(&trf->lock);
582 return IRQ_NONE;
583 }
584
585 ret = trf7970a_read_irqstatus(trf, &status);
586 if (ret) {
587 mutex_unlock(&trf->lock);
588 return IRQ_NONE;
589 }
590
591 dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
592 status);
593
594 if (!status) {
595 mutex_unlock(&trf->lock);
596 return IRQ_NONE;
597 }
598
599 switch (trf->state) {
600 case TRF7970A_ST_IDLE:
601 case TRF7970A_ST_IDLE_RX_BLOCKED:
602 /* If getting interrupts caused by RF noise, turn off the
603 * receiver to avoid unnecessary interrupts. It will be
604 * turned back on in trf7970a_in_send_cmd() when the next
605 * command is issued.
606 */
607 if (status & TRF7970A_IRQ_STATUS_ERROR) {
608 trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
609 trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
610 }
611
612 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
613 break;
614 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
615 if (status & TRF7970A_IRQ_STATUS_TX) {
616 trf->ignore_timeout =
617 !cancel_delayed_work(&trf->timeout_work);
618 trf7970a_fill_fifo(trf);
619 } else {
620 trf7970a_send_err_upstream(trf, -EIO);
621 }
622 break;
623 case TRF7970A_ST_WAIT_FOR_RX_DATA:
624 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
625 if (status & TRF7970A_IRQ_STATUS_SRX) {
626 trf->ignore_timeout =
627 !cancel_delayed_work(&trf->timeout_work);
628 trf7970a_drain_fifo(trf, status);
629 } else if (!(status & TRF7970A_IRQ_STATUS_TX)) {
630 trf7970a_send_err_upstream(trf, -EIO);
631 }
632 break;
633 default:
634 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
635 __func__, trf->state);
636 }
637
638 mutex_unlock(&trf->lock);
639 return IRQ_HANDLED;
640}
641
642static void trf7970a_timeout_work_handler(struct work_struct *work)
643{
644 struct trf7970a *trf = container_of(work, struct trf7970a,
645 timeout_work.work);
646
647 dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
648 trf->state, trf->ignore_timeout);
649
650 mutex_lock(&trf->lock);
651
652 if (trf->ignore_timeout)
653 trf->ignore_timeout = false;
654 else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
655 trf7970a_send_upstream(trf); /* No more rx data so send up */
656 else
657 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
658
659 mutex_unlock(&trf->lock);
660}
661
662static int trf7970a_init(struct trf7970a *trf)
663{
664 int ret;
665
666 dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
667
668 ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
669 if (ret)
670 goto err_out;
671
672 ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
673 if (ret)
674 goto err_out;
675
676 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
677 TRF7970A_MODULATOR_DEPTH_OOK);
678 if (ret)
679 goto err_out;
680
681 ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
682 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
683 TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
684 if (ret)
685 goto err_out;
686
687 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
688 if (ret)
689 goto err_out;
690
691 trf->special_fcn_reg1 = 0;
692
693 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
694 TRF7970A_CHIP_STATUS_RF_ON |
695 TRF7970A_CHIP_STATUS_VRS5_3);
696 if (ret)
697 goto err_out;
698
699 return 0;
700
701err_out:
702 dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
703 return ret;
704}
705
706static void trf7970a_switch_rf_off(struct trf7970a *trf)
707{
708 dev_dbg(trf->dev, "Switching rf off\n");
709
710 gpio_set_value(trf->en_gpio, 0);
711 gpio_set_value(trf->en2_gpio, 0);
712
713 trf->aborting = false;
714 trf->state = TRF7970A_ST_OFF;
715}
716
717static int trf7970a_switch_rf_on(struct trf7970a *trf)
718{
719 unsigned long delay;
720 int ret;
721
722 dev_dbg(trf->dev, "Switching rf on\n");
723
724 if (trf->powering_up)
725 usleep_range(5000, 6000);
726
727 gpio_set_value(trf->en2_gpio, 1);
728 usleep_range(1000, 2000);
729 gpio_set_value(trf->en_gpio, 1);
730
731 /* The delay between enabling the trf7970a and issuing the first
732 * command is significantly longer the very first time after powering
733 * up. Make sure the longer delay is only done the first time.
734 */
735 if (trf->powering_up) {
736 delay = 20000;
737 trf->powering_up = false;
738 } else {
739 delay = 5000;
740 }
741
742 usleep_range(delay, delay + 1000);
743
744 ret = trf7970a_init(trf);
745 if (ret)
746 trf7970a_switch_rf_off(trf);
747 else
748 trf->state = TRF7970A_ST_IDLE;
749
750 return ret;
751}
752
753static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
754{
755 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
756 int ret = 0;
757
758 dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
759
760 mutex_lock(&trf->lock);
761
762 if (on) {
763 switch (trf->state) {
764 case TRF7970A_ST_OFF:
765 ret = trf7970a_switch_rf_on(trf);
766 break;
767 case TRF7970A_ST_IDLE:
768 case TRF7970A_ST_IDLE_RX_BLOCKED:
769 break;
770 default:
771 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
772 __func__, trf->state, on);
773 trf7970a_switch_rf_off(trf);
774 }
775 } else {
776 switch (trf->state) {
777 case TRF7970A_ST_OFF:
778 break;
779 default:
780 dev_err(trf->dev, "%s - Invalid request: %d %d\n",
781 __func__, trf->state, on);
782 /* FALLTHROUGH */
783 case TRF7970A_ST_IDLE:
784 case TRF7970A_ST_IDLE_RX_BLOCKED:
785 trf7970a_switch_rf_off(trf);
786 }
787 }
788
789 mutex_unlock(&trf->lock);
790 return ret;
791}
792
793static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech)
794{
795 int ret = 0;
796
797 dev_dbg(trf->dev, "rf technology: %d\n", tech);
798
799 switch (tech) {
800 case NFC_DIGITAL_RF_TECH_106A:
801 trf->iso_ctrl = TRF7970A_ISO_CTRL_14443A_106;
802 break;
803 default:
804 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
805 return -EINVAL;
806 }
807
808 trf->technology = tech;
809
810 return ret;
811}
812
813static int trf7970a_config_framing(struct trf7970a *trf, int framing)
814{
815 dev_dbg(trf->dev, "framing: %d\n", framing);
816
817 switch (framing) {
818 case NFC_DIGITAL_FRAMING_NFCA_SHORT:
819 case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
820 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
821 trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
822 break;
823 case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
824 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
825 trf->iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
826 break;
827 case NFC_DIGITAL_FRAMING_NFCA_T2T:
828 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
829 trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
830 break;
831 default:
832 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
833 return -EINVAL;
834 }
835
836 trf->framing = framing;
837
838 return trf7970a_write(trf, TRF7970A_ISO_CTRL, trf->iso_ctrl);
839}
840
841static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
842 int param)
843{
844 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
845 int ret = 0;
846
847 dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
848
849 mutex_lock(&trf->lock);
850
851 if (trf->state == TRF7970A_ST_OFF) {
852 ret = trf7970a_switch_rf_on(trf);
853 if (ret)
854 goto err_out;
855 }
856
857 switch (type) {
858 case NFC_DIGITAL_CONFIG_RF_TECH:
859 ret = trf7970a_config_rf_tech(trf, param);
860 break;
861 case NFC_DIGITAL_CONFIG_FRAMING:
862 ret = trf7970a_config_framing(trf, param);
863 break;
864 default:
865 dev_dbg(trf->dev, "Unknown type: %d\n", type);
866 ret = -EINVAL;
867 }
868
869err_out:
870 mutex_unlock(&trf->lock);
871 return ret;
872}
873
874static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
875{
876 u8 *req = skb->data;
877 u8 special_fcn_reg1;
878 int ret;
879
880 /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
881 * special functions register 1 is cleared; otherwise, its a write or
882 * sector select command and '4_bit_RX' must be set.
883 */
884 if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
885 (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
886 if (req[0] == NFC_T2T_CMD_READ)
887 special_fcn_reg1 = 0;
888 else
889 special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
890
891 if (special_fcn_reg1 != trf->special_fcn_reg1) {
892 ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
893 special_fcn_reg1);
894 if (ret)
895 return ret;
896
897 trf->special_fcn_reg1 = special_fcn_reg1;
898 }
899 }
900
901 return 0;
902}
903
904static int trf7970a_in_send_cmd(struct nfc_digital_dev *ddev,
905 struct sk_buff *skb, u16 timeout,
906 nfc_digital_cmd_complete_t cb, void *arg)
907{
908 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
909 char *prefix;
910 unsigned int len;
911 int ret;
912
913 dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
914 trf->state, timeout, skb->len);
915
916 if (skb->len > TRF7970A_TX_MAX)
917 return -EINVAL;
918
919 mutex_lock(&trf->lock);
920
921 if ((trf->state != TRF7970A_ST_IDLE) &&
922 (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
923 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
924 trf->state);
925 ret = -EIO;
926 goto out_err;
927 }
928
929 if (trf->aborting) {
930 dev_dbg(trf->dev, "Abort process complete\n");
931 trf->aborting = false;
932 ret = -ECANCELED;
933 goto out_err;
934 }
935
936 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
937 GFP_KERNEL);
938 if (!trf->rx_skb) {
939 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
940 ret = -ENOMEM;
941 goto out_err;
942 }
943
944 if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
945 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
946 if (ret)
947 goto out_err;
948
949 trf->state = TRF7970A_ST_IDLE;
950 }
951
952 ret = trf7970a_per_cmd_config(trf, skb);
953 if (ret)
954 goto out_err;
955
956 trf->ddev = ddev;
957 trf->tx_skb = skb;
958 trf->cb = cb;
959 trf->cb_arg = arg;
960 trf->timeout = timeout;
961 trf->ignore_timeout = false;
962
963 len = skb->len;
964 prefix = skb_push(skb, TRF7970A_TX_SKB_HEADROOM);
965
966 /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
967 * on what the current framing is, the address of the TX length byte 1
968 * register (0x1d), and the 2 byte length of the data to be transmitted.
969 */
970 prefix[0] = TRF7970A_CMD_BIT_CTRL |
971 TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
972 prefix[1] = TRF7970A_CMD_BIT_CTRL |
973 TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
974 prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
975
976 if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
977 prefix[3] = 0x00;
978 prefix[4] = 0x0f; /* 7 bits */
979 } else {
980 prefix[3] = (len & 0xf00) >> 4;
981 prefix[3] |= ((len & 0xf0) >> 4);
982 prefix[4] = ((len & 0x0f) << 4);
983 }
984
985 len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
986
987 usleep_range(1000, 2000);
988
989 ret = trf7970a_transmit(trf, skb, len);
990 if (ret) {
991 kfree_skb(trf->rx_skb);
992 trf->rx_skb = NULL;
993 }
994
995out_err:
996 mutex_unlock(&trf->lock);
997 return ret;
998}
999
1000static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev,
1001 int type, int param)
1002{
1003 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1004
1005 dev_dbg(trf->dev, "Unsupported interface\n");
1006
1007 return -EINVAL;
1008}
1009
1010static int trf7970a_tg_send_cmd(struct nfc_digital_dev *ddev,
1011 struct sk_buff *skb, u16 timeout,
1012 nfc_digital_cmd_complete_t cb, void *arg)
1013{
1014 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1015
1016 dev_dbg(trf->dev, "Unsupported interface\n");
1017
1018 return -EINVAL;
1019}
1020
1021static int trf7970a_tg_listen(struct nfc_digital_dev *ddev,
1022 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1023{
1024 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1025
1026 dev_dbg(trf->dev, "Unsupported interface\n");
1027
1028 return -EINVAL;
1029}
1030
1031static int trf7970a_tg_listen_mdaa(struct nfc_digital_dev *ddev,
1032 struct digital_tg_mdaa_params *mdaa_params,
1033 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1034{
1035 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1036
1037 dev_dbg(trf->dev, "Unsupported interface\n");
1038
1039 return -EINVAL;
1040}
1041
1042static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1043{
1044 struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1045
1046 dev_dbg(trf->dev, "Abort process initiated\n");
1047
1048 mutex_lock(&trf->lock);
1049 trf->aborting = true;
1050 mutex_unlock(&trf->lock);
1051}
1052
1053static struct nfc_digital_ops trf7970a_nfc_ops = {
1054 .in_configure_hw = trf7970a_in_configure_hw,
1055 .in_send_cmd = trf7970a_in_send_cmd,
1056 .tg_configure_hw = trf7970a_tg_configure_hw,
1057 .tg_send_cmd = trf7970a_tg_send_cmd,
1058 .tg_listen = trf7970a_tg_listen,
1059 .tg_listen_mdaa = trf7970a_tg_listen_mdaa,
1060 .switch_rf = trf7970a_switch_rf,
1061 .abort_cmd = trf7970a_abort_cmd,
1062};
1063
1064static int trf7970a_probe(struct spi_device *spi)
1065{
1066 struct device_node *np = spi->dev.of_node;
1067 const struct spi_device_id *id = spi_get_device_id(spi);
1068 struct trf7970a *trf;
1069 int ret;
1070
1071 if (!np) {
1072 dev_err(&spi->dev, "No Device Tree entry\n");
1073 return -EINVAL;
1074 }
1075
1076 trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
1077 if (!trf)
1078 return -ENOMEM;
1079
1080 trf->state = TRF7970A_ST_OFF;
1081 trf->dev = &spi->dev;
1082 trf->spi = spi;
1083 trf->quirks = id->driver_data;
1084
1085 spi->mode = SPI_MODE_1;
1086 spi->bits_per_word = 8;
1087
1088 /* There are two enable pins - both must be present */
1089 trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
1090 if (!gpio_is_valid(trf->en_gpio)) {
1091 dev_err(trf->dev, "No EN GPIO property\n");
1092 return trf->en_gpio;
1093 }
1094
1095 ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
1096 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "EN");
1097 if (ret) {
1098 dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
1099 return ret;
1100 }
1101
1102 trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
1103 if (!gpio_is_valid(trf->en2_gpio)) {
1104 dev_err(trf->dev, "No EN2 GPIO property\n");
1105 return trf->en2_gpio;
1106 }
1107
1108 ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
1109 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "EN2");
1110 if (ret) {
1111 dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
1112 return ret;
1113 }
1114
1115 ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
1116 trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1117 "trf7970a", trf);
1118 if (ret) {
1119 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
1120 return ret;
1121 }
1122
1123 mutex_init(&trf->lock);
1124 INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
1125
1126 trf->regulator = devm_regulator_get(&spi->dev, "vin");
1127 if (IS_ERR(trf->regulator)) {
1128 ret = PTR_ERR(trf->regulator);
1129 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
1130 goto err_destroy_lock;
1131 }
1132
1133 ret = regulator_enable(trf->regulator);
1134 if (ret) {
1135 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
1136 goto err_destroy_lock;
1137 }
1138
1139 trf->powering_up = true;
1140
1141 trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
1142 TRF7970A_SUPPORTED_PROTOCOLS,
1143 NFC_DIGITAL_DRV_CAPS_IN_CRC, TRF7970A_TX_SKB_HEADROOM,
1144 0);
1145 if (!trf->ddev) {
1146 dev_err(trf->dev, "Can't allocate NFC digital device\n");
1147 ret = -ENOMEM;
1148 goto err_disable_regulator;
1149 }
1150
1151 nfc_digital_set_parent_dev(trf->ddev, trf->dev);
1152 nfc_digital_set_drvdata(trf->ddev, trf);
1153 spi_set_drvdata(spi, trf);
1154
1155 ret = nfc_digital_register_device(trf->ddev);
1156 if (ret) {
1157 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
1158 ret);
1159 goto err_free_ddev;
1160 }
1161
1162 return 0;
1163
1164err_free_ddev:
1165 nfc_digital_free_device(trf->ddev);
1166err_disable_regulator:
1167 regulator_disable(trf->regulator);
1168err_destroy_lock:
1169 mutex_destroy(&trf->lock);
1170 return ret;
1171}
1172
1173static int trf7970a_remove(struct spi_device *spi)
1174{
1175 struct trf7970a *trf = spi_get_drvdata(spi);
1176
1177 mutex_lock(&trf->lock);
1178
1179 trf7970a_switch_rf_off(trf);
1180 trf7970a_init(trf);
1181
1182 switch (trf->state) {
1183 case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1184 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1185 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1186 trf7970a_send_err_upstream(trf, -ECANCELED);
1187 break;
1188 default:
1189 break;
1190 }
1191
1192 mutex_unlock(&trf->lock);
1193
1194 nfc_digital_unregister_device(trf->ddev);
1195 nfc_digital_free_device(trf->ddev);
1196
1197 regulator_disable(trf->regulator);
1198
1199 mutex_destroy(&trf->lock);
1200
1201 return 0;
1202}
1203
1204static const struct spi_device_id trf7970a_id_table[] = {
1205 { "trf7970a", TRF7970A_QUIRK_IRQ_STATUS_READ_ERRATA },
1206 { }
1207};
1208MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
1209
1210static struct spi_driver trf7970a_spi_driver = {
1211 .probe = trf7970a_probe,
1212 .remove = trf7970a_remove,
1213 .id_table = trf7970a_id_table,
1214 .driver = {
1215 .name = "trf7970a",
1216 .owner = THIS_MODULE,
1217 },
1218};
1219
1220module_spi_driver(trf7970a_spi_driver);
1221
1222MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
1223MODULE_LICENSE("GPL v2");
1224MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-18 14:18:17 -0500