1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Driver for ITE Tech Inc. IT8712F/IT8512F CIR
4 *
5 * Copyright (C) 2010 Juan Jesús García de Soria <skandalfo@gmail.com>
6 */
7
8/* platform driver name to register */
9#define ITE_DRIVER_NAME "ite-cir"
10
11/* logging macros */
12#define ite_pr(level, text, ...) \
13	printk(level KBUILD_MODNAME ": " text, ## __VA_ARGS__)
14#define ite_dbg(text, ...) do { \
15	if (debug) \
16		printk(KERN_DEBUG \
17			KBUILD_MODNAME ": " text "\n" , ## __VA_ARGS__); \
18} while (0)
19
20#define ite_dbg_verbose(text, ...) do {\
21	if (debug > 1) \
22		printk(KERN_DEBUG \
23			KBUILD_MODNAME ": " text "\n" , ## __VA_ARGS__); \
24} while (0)
25
26/* FIFO sizes */
27#define ITE_TX_FIFO_LEN 32
28#define ITE_RX_FIFO_LEN 32
29
30/* interrupt types */
31#define ITE_IRQ_TX_FIFO        1
32#define ITE_IRQ_RX_FIFO        2
33#define ITE_IRQ_RX_FIFO_OVERRUN    4
34
35/* forward declaration */
36struct ite_dev;
37
38/* struct for storing the parameters of different recognized devices */
39struct ite_dev_params {
40	/* model of the device */
41	const char *model;
42
43	/* size of the I/O region */
44	int io_region_size;
45
46	/* IR pnp I/O resource number */
47	int io_rsrc_no;
48
49	/* true if the hardware supports transmission */
50	bool hw_tx_capable;
51
52	/* base sampling period, in ns */
53	u32 sample_period;
54
55	/* rx low carrier frequency, in Hz, 0 means no demodulation */
56	unsigned int rx_low_carrier_freq;
57
58	/* tx high carrier frequency, in Hz, 0 means no demodulation */
59	unsigned int rx_high_carrier_freq;
60
61	/* tx carrier frequency, in Hz */
62	unsigned int tx_carrier_freq;
63
64	/* duty cycle, 0-100 */
65	int tx_duty_cycle;
66
67	/* hw-specific operation function pointers; most of these must be
68	 * called while holding the spin lock, except for the TX FIFO length
69	 * one */
70	/* get pending interrupt causes */
71	int (*get_irq_causes) (struct ite_dev *dev);
72
73	/* enable rx */
74	void (*enable_rx) (struct ite_dev *dev);
75
76	/* make rx enter the idle state; keep listening for a pulse, but stop
77	 * streaming space bytes */
78	void (*idle_rx) (struct ite_dev *dev);
79
80	/* disable rx completely */
81	void (*disable_rx) (struct ite_dev *dev);
82
83	/* read bytes from RX FIFO; return read count */
84	int (*get_rx_bytes) (struct ite_dev *dev, u8 *buf, int buf_size);
85
86	/* enable tx FIFO space available interrupt */
87	void (*enable_tx_interrupt) (struct ite_dev *dev);
88
89	/* disable tx FIFO space available interrupt */
90	void (*disable_tx_interrupt) (struct ite_dev *dev);
91
92	/* get number of full TX FIFO slots */
93	int (*get_tx_used_slots) (struct ite_dev *dev);
94
95	/* put a byte to the TX FIFO */
96	void (*put_tx_byte) (struct ite_dev *dev, u8 value);
97
98	/* disable hardware completely */
99	void (*disable) (struct ite_dev *dev);
100
101	/* initialize the hardware */
102	void (*init_hardware) (struct ite_dev *dev);
103
104	/* set the carrier parameters */
105	void (*set_carrier_params) (struct ite_dev *dev, bool high_freq,
106				    bool use_demodulator, u8 carrier_freq_bits,
107				    u8 allowance_bits, u8 pulse_width_bits);
108};
109
110/* ITE CIR device structure */
111struct ite_dev {
112	struct pnp_dev *pdev;
113	struct rc_dev *rdev;
114	struct ir_raw_event rawir;
115
116	/* sync data */
117	spinlock_t lock;
118	bool in_use, transmitting;
119
120	/* transmit support */
121	int tx_fifo_allowance;
122	wait_queue_head_t tx_queue, tx_ended;
123
124	/* hardware I/O settings */
125	unsigned long cir_addr;
126	int cir_irq;
127
128	/* overridable copy of model parameters */
129	struct ite_dev_params params;
130};
131
132/* common values for all kinds of hardware */
133
134/* baud rate divisor default */
135#define ITE_BAUDRATE_DIVISOR		1
136
137/* low-speed carrier frequency limits (Hz) */
138#define ITE_LCF_MIN_CARRIER_FREQ	27000
139#define ITE_LCF_MAX_CARRIER_FREQ	58000
140
141/* high-speed carrier frequency limits (Hz) */
142#define ITE_HCF_MIN_CARRIER_FREQ	400000
143#define ITE_HCF_MAX_CARRIER_FREQ	500000
144
145/* default carrier freq for when demodulator is off (Hz) */
146#define ITE_DEFAULT_CARRIER_FREQ	38000
147
148/* convert bits to us */
149#define ITE_BITS_TO_US(bits, sample_period) \
150((u32)((bits) * ITE_BAUDRATE_DIVISOR * (sample_period) / 1000))
151
152/*
153 * n in RDCR produces a tolerance of +/- n * 6.25% around the center
154 * carrier frequency...
155 *
156 * From two limit frequencies, L (low) and H (high), we can get both the
157 * center frequency F = (L + H) / 2 and the variation from the center
158 * frequency A = (H - L) / (H + L). We can use this in order to honor the
159 * s_rx_carrier_range() call in ir-core. We'll suppose that any request
160 * setting L=0 means we must shut down the demodulator.
161 */
162#define ITE_RXDCR_PER_10000_STEP 625
163
164/* high speed carrier freq values */
165#define ITE_CFQ_400		0x03
166#define ITE_CFQ_450		0x08
167#define ITE_CFQ_480		0x0b
168#define ITE_CFQ_500		0x0d
169
170/* values for pulse widths */
171#define ITE_TXMPW_A		0x02
172#define ITE_TXMPW_B		0x03
173#define ITE_TXMPW_C		0x04
174#define ITE_TXMPW_D		0x05
175#define ITE_TXMPW_E		0x06
176
177/* values for demodulator carrier range allowance */
178#define ITE_RXDCR_DEFAULT	0x01	/* default carrier range */
179#define ITE_RXDCR_MAX		0x07	/* default carrier range */
180
181/* DR TX bits */
182#define ITE_TX_PULSE		0x00
183#define ITE_TX_SPACE		0x80
184#define ITE_TX_MAX_RLE		0x80
185#define ITE_TX_RLE_MASK		0x7f
186
187/*
188 * IT8712F
189 *
190 * hardware data obtained from:
191 *
192 * IT8712F
193 * Environment Control – Low Pin Count Input / Output
194 * (EC - LPC I/O)
195 * Preliminary Specification V0. 81
196 */
197
198/* register offsets */
199#define IT87_DR		0x00	/* data register */
200#define IT87_IER	0x01	/* interrupt enable register */
201#define IT87_RCR	0x02	/* receiver control register */
202#define IT87_TCR1	0x03	/* transmitter control register 1 */
203#define IT87_TCR2	0x04	/* transmitter control register 2 */
204#define IT87_TSR	0x05	/* transmitter status register */
205#define IT87_RSR	0x06	/* receiver status register */
206#define IT87_BDLR	0x05	/* baud rate divisor low byte register */
207#define IT87_BDHR	0x06	/* baud rate divisor high byte register */
208#define IT87_IIR	0x07	/* interrupt identification register */
209
210#define IT87_IOREG_LENGTH 0x08	/* length of register file */
211
212/* IER bits */
213#define IT87_TLDLIE	0x01	/* transmitter low data interrupt enable */
214#define IT87_RDAIE	0x02	/* receiver data available interrupt enable */
215#define IT87_RFOIE	0x04	/* receiver FIFO overrun interrupt enable */
216#define IT87_IEC	0x08	/* interrupt enable control */
217#define IT87_BR		0x10	/* baud rate register enable */
218#define IT87_RESET	0x20	/* reset */
219
220/* RCR bits */
221#define IT87_RXDCR	0x07	/* receiver demodulation carrier range mask */
222#define IT87_RXACT	0x08	/* receiver active */
223#define IT87_RXEND	0x10	/* receiver demodulation enable */
224#define IT87_RXEN	0x20	/* receiver enable */
225#define IT87_HCFS	0x40	/* high-speed carrier frequency select */
226#define IT87_RDWOS	0x80	/* receiver data without sync */
227
228/* TCR1 bits */
229#define IT87_TXMPM	0x03	/* transmitter modulation pulse mode mask */
230#define IT87_TXMPM_DEFAULT 0x00	/* modulation pulse mode default */
231#define IT87_TXENDF	0x04	/* transmitter deferral */
232#define IT87_TXRLE	0x08	/* transmitter run length enable */
233#define IT87_FIFOTL	0x30	/* FIFO level threshold mask */
234#define IT87_FIFOTL_DEFAULT 0x20	/* FIFO level threshold default
235					 * 0x00 -> 1, 0x10 -> 7, 0x20 -> 17,
236					 * 0x30 -> 25 */
237#define IT87_ILE	0x40	/* internal loopback enable */
238#define IT87_FIFOCLR	0x80	/* FIFO clear bit */
239
240/* TCR2 bits */
241#define IT87_TXMPW	0x07	/* transmitter modulation pulse width mask */
242#define IT87_TXMPW_DEFAULT 0x04	/* default modulation pulse width */
243#define IT87_CFQ	0xf8	/* carrier frequency mask */
244#define IT87_CFQ_SHIFT	3	/* carrier frequency bit shift */
245
246/* TSR bits */
247#define IT87_TXFBC	0x3f	/* transmitter FIFO byte count mask */
248
249/* RSR bits */
250#define IT87_RXFBC	0x3f	/* receiver FIFO byte count mask */
251#define IT87_RXFTO	0x80	/* receiver FIFO time-out */
252
253/* IIR bits */
254#define IT87_IP		0x01	/* interrupt pending */
255#define IT87_II		0x06	/* interrupt identification mask */
256#define IT87_II_NOINT	0x00	/* no interrupt */
257#define IT87_II_TXLDL	0x02	/* transmitter low data level */
258#define IT87_II_RXDS	0x04	/* receiver data stored */
259#define IT87_II_RXFO	0x06	/* receiver FIFO overrun */
260
261/*
262 * IT8512E/F
263 *
264 * Hardware data obtained from:
265 *
266 * IT8512E/F
267 * Embedded Controller
268 * Preliminary Specification V0.4.1
269 *
270 * Note that the CIR registers are not directly available to the host, because
271 * they only are accessible to the integrated microcontroller. Thus, in order
272 * use it, some kind of bridging is required. As the bridging may depend on
273 * the controller firmware in use, we are going to use the PNP ID in order to
274 * determine the strategy and ports available. See after these generic
275 * IT8512E/F register definitions for register definitions for those
276 * strategies.
277 */
278
279/* register offsets */
280#define IT85_C0DR	0x00	/* data register */
281#define IT85_C0MSTCR	0x01	/* master control register */
282#define IT85_C0IER	0x02	/* interrupt enable register */
283#define IT85_C0IIR	0x03	/* interrupt identification register */
284#define IT85_C0CFR	0x04	/* carrier frequency register */
285#define IT85_C0RCR	0x05	/* receiver control register */
286#define IT85_C0TCR	0x06	/* transmitter control register */
287#define IT85_C0SCK	0x07	/* slow clock control register */
288#define IT85_C0BDLR	0x08	/* baud rate divisor low byte register */
289#define IT85_C0BDHR	0x09	/* baud rate divisor high byte register */
290#define IT85_C0TFSR	0x0a	/* transmitter FIFO status register */
291#define IT85_C0RFSR	0x0b	/* receiver FIFO status register */
292#define IT85_C0WCL	0x0d	/* wakeup code length register */
293#define IT85_C0WCR	0x0e	/* wakeup code read/write register */
294#define IT85_C0WPS	0x0f	/* wakeup power control/status register */
295
296#define IT85_IOREG_LENGTH 0x10	/* length of register file */
297
298/* C0MSTCR bits */
299#define IT85_RESET	0x01	/* reset */
300#define IT85_FIFOCLR	0x02	/* FIFO clear bit */
301#define IT85_FIFOTL	0x0c	/* FIFO level threshold mask */
302#define IT85_FIFOTL_DEFAULT 0x08	/* FIFO level threshold default
303					 * 0x00 -> 1, 0x04 -> 7, 0x08 -> 17,
304					 * 0x0c -> 25 */
305#define IT85_ILE	0x10	/* internal loopback enable */
306#define IT85_ILSEL	0x20	/* internal loopback select */
307
308/* C0IER bits */
309#define IT85_TLDLIE	0x01	/* TX low data level interrupt enable */
310#define IT85_RDAIE	0x02	/* RX data available interrupt enable */
311#define IT85_RFOIE	0x04	/* RX FIFO overrun interrupt enable */
312#define IT85_IEC	0x80	/* interrupt enable function control */
313
314/* C0IIR bits */
315#define IT85_TLDLI	0x01	/* transmitter low data level interrupt */
316#define IT85_RDAI	0x02	/* receiver data available interrupt */
317#define IT85_RFOI	0x04	/* receiver FIFO overrun interrupt */
318#define IT85_NIP	0x80	/* no interrupt pending */
319
320/* C0CFR bits */
321#define IT85_CFQ	0x1f	/* carrier frequency mask */
322#define IT85_HCFS	0x20	/* high speed carrier frequency select */
323
324/* C0RCR bits */
325#define IT85_RXDCR	0x07	/* receiver demodulation carrier range mask */
326#define IT85_RXACT	0x08	/* receiver active */
327#define IT85_RXEND	0x10	/* receiver demodulation enable */
328#define IT85_RDWOS	0x20	/* receiver data without sync */
329#define IT85_RXEN	0x80	/* receiver enable */
330
331/* C0TCR bits */
332#define IT85_TXMPW	0x07	/* transmitter modulation pulse width mask */
333#define IT85_TXMPW_DEFAULT 0x04	/* default modulation pulse width */
334#define IT85_TXMPM	0x18	/* transmitter modulation pulse mode mask */
335#define IT85_TXMPM_DEFAULT 0x00	/* modulation pulse mode default */
336#define IT85_TXENDF	0x20	/* transmitter deferral */
337#define IT85_TXRLE	0x40	/* transmitter run length enable */
338
339/* C0SCK bits */
340#define IT85_SCKS	0x01	/* slow clock select */
341#define IT85_TXDCKG	0x02	/* TXD clock gating */
342#define IT85_DLL1P8E	0x04	/* DLL 1.8432M enable */
343#define IT85_DLLTE	0x08	/* DLL test enable */
344#define IT85_BRCM	0x70	/* baud rate count mode */
345#define IT85_DLLOCK	0x80	/* DLL lock */
346
347/* C0TFSR bits */
348#define IT85_TXFBC	0x3f	/* transmitter FIFO count mask */
349
350/* C0RFSR bits */
351#define IT85_RXFBC	0x3f	/* receiver FIFO count mask */
352#define IT85_RXFTO	0x80	/* receiver FIFO time-out */
353
354/* C0WCL bits */
355#define IT85_WCL	0x3f	/* wakeup code length mask */
356
357/* C0WPS bits */
358#define IT85_CIRPOSIE	0x01	/* power on/off status interrupt enable */
359#define IT85_CIRPOIS	0x02	/* power on/off interrupt status */
360#define IT85_CIRPOII	0x04	/* power on/off interrupt identification */
361#define IT85_RCRST	0x10	/* wakeup code reading counter reset bit */
362#define IT85_WCRST	0x20	/* wakeup code writing counter reset bit */
363
364/*
365 * ITE8708
366 *
367 * Hardware data obtained from hacked driver for IT8512 in this forum post:
368 *
369 *  http://ubuntuforums.org/showthread.php?t=1028640
370 *
371 * Although there's no official documentation for that driver, analysis would
372 * suggest that it maps the 16 registers of IT8512 onto two 8-register banks,
373 * selectable by a single bank-select bit that's mapped onto both banks. The
374 * IT8512 registers are mapped in a different order, so that the first bank
375 * maps the ones that are used more often, and two registers that share a
376 * reserved high-order bit are placed at the same offset in both banks in
377 * order to reuse the reserved bit as the bank select bit.
378 */
379
380/* register offsets */
381
382/* mapped onto both banks */
383#define IT8708_BANKSEL	0x07	/* bank select register */
384#define IT8708_HRAE	0x80	/* high registers access enable */
385
386/* mapped onto the low bank */
387#define IT8708_C0DR	0x00	/* data register */
388#define IT8708_C0MSTCR	0x01	/* master control register */
389#define IT8708_C0IER	0x02	/* interrupt enable register */
390#define IT8708_C0IIR	0x03	/* interrupt identification register */
391#define IT8708_C0RFSR	0x04	/* receiver FIFO status register */
392#define IT8708_C0RCR	0x05	/* receiver control register */
393#define IT8708_C0TFSR	0x06	/* transmitter FIFO status register */
394#define IT8708_C0TCR	0x07	/* transmitter control register */
395
396/* mapped onto the high bank */
397#define IT8708_C0BDLR	0x01	/* baud rate divisor low byte register */
398#define IT8708_C0BDHR	0x02	/* baud rate divisor high byte register */
399#define IT8708_C0CFR	0x04	/* carrier frequency register */
400
401/* registers whose bank mapping we don't know, since they weren't being used
402 * in the hacked driver... most probably they belong to the high bank too,
403 * since they fit in the holes the other registers leave */
404#define IT8708_C0SCK	0x03	/* slow clock control register */
405#define IT8708_C0WCL	0x05	/* wakeup code length register */
406#define IT8708_C0WCR	0x06	/* wakeup code read/write register */
407#define IT8708_C0WPS	0x07	/* wakeup power control/status register */
408
409#define IT8708_IOREG_LENGTH 0x08	/* length of register file */
410
411/* two more registers that are defined in the hacked driver, but can't be
412 * found in the data sheets; no idea what they are or how they are accessed,
413 * since the hacked driver doesn't seem to use them */
414#define IT8708_CSCRR	0x00
415#define IT8708_CGPINTR	0x01
416
417/* CSCRR bits */
418#define IT8708_CSCRR_SCRB 0x3f
419#define IT8708_CSCRR_PM	0x80
420
421/* CGPINTR bits */
422#define IT8708_CGPINT	0x01
423
424/*
425 * ITE8709
426 *
427 * Hardware interfacing data obtained from the original lirc_ite8709 driver.
428 * Verbatim from its sources:
429 *
430 * The ITE8709 device seems to be the combination of IT8512 superIO chip and
431 * a specific firmware running on the IT8512's embedded micro-controller.
432 * In addition of the embedded micro-controller, the IT8512 chip contains a
433 * CIR module and several other modules. A few modules are directly accessible
434 * by the host CPU, but most of them are only accessible by the
435 * micro-controller. The CIR module is only accessible by the
436 * micro-controller.
437 *
438 * The battery-backed SRAM module is accessible by the host CPU and the
439 * micro-controller. So one of the MC's firmware role is to act as a bridge
440 * between the host CPU and the CIR module. The firmware implements a kind of
441 * communication protocol using the SRAM module as a shared memory. The IT8512
442 * specification is publicly available on ITE's web site, but the
443 * communication protocol is not, so it was reverse-engineered.
444 */
445
446/* register offsets */
447#define IT8709_RAM_IDX	0x00	/* index into the SRAM module bytes */
448#define IT8709_RAM_VAL	0x01	/* read/write data to the indexed byte */
449
450#define IT8709_IOREG_LENGTH 0x02	/* length of register file */
451
452/* register offsets inside the SRAM module */
453#define IT8709_MODE	0x1a	/* request/ack byte */
454#define IT8709_REG_IDX	0x1b	/* index of the CIR register to access */
455#define IT8709_REG_VAL	0x1c	/* value read/to be written */
456#define IT8709_IIR	0x1e	/* interrupt identification register */
457#define IT8709_RFSR	0x1f	/* receiver FIFO status register */
458#define IT8709_FIFO	0x20	/* start of in RAM RX FIFO copy */
459
460/* MODE values */
461#define IT8709_IDLE	0x00
462#define IT8709_WRITE	0x01
463#define IT8709_READ	0x02
464