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