1/*
2 * Driver for ITE Tech Inc. IT8712F/IT8512F CIR
3 *
4 * Copyright (C) 2010 Juan Jesús García de Soria <skandalfo@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation; either version 2 of the
9 * License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19 * USA.
20 */
21
22/* platform driver name to register */
23#define ITE_DRIVER_NAME "ite-cir"
24
25/* logging macros */
26#define ite_pr(level, text, ...) \
27	printk(level KBUILD_MODNAME ": " text, ## __VA_ARGS__)
28#define ite_dbg(text, ...) do { \
29	if (debug) \
30		printk(KERN_DEBUG \
31			KBUILD_MODNAME ": " text "\n" , ## __VA_ARGS__); \
32} while (0)
33
34#define ite_dbg_verbose(text, ...) do {\
35	if (debug > 1) \
36		printk(KERN_DEBUG \
37			KBUILD_MODNAME ": " text "\n" , ## __VA_ARGS__); \
38} while (0)
39
40/* FIFO sizes */
41#define ITE_TX_FIFO_LEN 32
42#define ITE_RX_FIFO_LEN 32
43
44/* interrupt types */
45#define ITE_IRQ_TX_FIFO        1
46#define ITE_IRQ_RX_FIFO        2
47#define ITE_IRQ_RX_FIFO_OVERRUN    4
48
49/* forward declaration */
50struct ite_dev;
51
52/* struct for storing the parameters of different recognized devices */
53struct ite_dev_params {
54	/* model of the device */
55	const char *model;
56
57	/* size of the I/O region */
58	int io_region_size;
59
60	/* IR pnp I/O resource number */
61	int io_rsrc_no;
62
63	/* true if the hardware supports transmission */
64	bool hw_tx_capable;
65
66	/* base sampling period, in ns */
67	u32 sample_period;
68
69	/* rx low carrier frequency, in Hz, 0 means no demodulation */
70	unsigned int rx_low_carrier_freq;
71
72	/* tx high carrier frequency, in Hz, 0 means no demodulation */
73	unsigned int rx_high_carrier_freq;
74
75	/* tx carrier frequency, in Hz */
76	unsigned int tx_carrier_freq;
77
78	/* duty cycle, 0-100 */
79	int tx_duty_cycle;
80
81	/* hw-specific operation function pointers; most of these must be
82	 * called while holding the spin lock, except for the TX FIFO length
83	 * one */
84	/* get pending interrupt causes */
85	int (*get_irq_causes) (struct ite_dev *dev);
86
87	/* enable rx */
88	void (*enable_rx) (struct ite_dev *dev);
89
90	/* make rx enter the idle state; keep listening for a pulse, but stop
91	 * streaming space bytes */
92	void (*idle_rx) (struct ite_dev *dev);
93
94	/* disable rx completely */
95	void (*disable_rx) (struct ite_dev *dev);
96
97	/* read bytes from RX FIFO; return read count */
98	int (*get_rx_bytes) (struct ite_dev *dev, u8 *buf, int buf_size);
99
100	/* enable tx FIFO space available interrupt */
101	void (*enable_tx_interrupt) (struct ite_dev *dev);
102
103	/* disable tx FIFO space available interrupt */
104	void (*disable_tx_interrupt) (struct ite_dev *dev);
105
106	/* get number of full TX FIFO slots */
107	int (*get_tx_used_slots) (struct ite_dev *dev);
108
109	/* put a byte to the TX FIFO */
110	void (*put_tx_byte) (struct ite_dev *dev, u8 value);
111
112	/* disable hardware completely */
113	void (*disable) (struct ite_dev *dev);
114
115	/* initialize the hardware */
116	void (*init_hardware) (struct ite_dev *dev);
117
118	/* set the carrier parameters */
119	void (*set_carrier_params) (struct ite_dev *dev, bool high_freq,
120				    bool use_demodulator, u8 carrier_freq_bits,
121				    u8 allowance_bits, u8 pulse_width_bits);
122};
123
124/* ITE CIR device structure */
125struct ite_dev {
126	struct pnp_dev *pdev;
127	struct rc_dev *rdev;
128	struct ir_raw_event rawir;
129
130	/* sync data */
131	spinlock_t lock;
132	bool in_use, transmitting;
133
134	/* transmit support */
135	int tx_fifo_allowance;
136	wait_queue_head_t tx_queue, tx_ended;
137
138	/* hardware I/O settings */
139	unsigned long cir_addr;
140	int cir_irq;
141
142	/* overridable copy of model parameters */
143	struct ite_dev_params params;
144};
145
146/* common values for all kinds of hardware */
147
148/* baud rate divisor default */
149#define ITE_BAUDRATE_DIVISOR		1
150
151/* low-speed carrier frequency limits (Hz) */
152#define ITE_LCF_MIN_CARRIER_FREQ	27000
153#define ITE_LCF_MAX_CARRIER_FREQ	58000
154
155/* high-speed carrier frequency limits (Hz) */
156#define ITE_HCF_MIN_CARRIER_FREQ	400000
157#define ITE_HCF_MAX_CARRIER_FREQ	500000
158
159/* default carrier freq for when demodulator is off (Hz) */
160#define ITE_DEFAULT_CARRIER_FREQ	38000
161
162/* default idling timeout in ns (0.2 seconds) */
163#define ITE_IDLE_TIMEOUT		200000000UL
164
165/* limit timeout values */
166#define ITE_MIN_IDLE_TIMEOUT		100000000UL
167#define ITE_MAX_IDLE_TIMEOUT		1000000000UL
168
169/* convert bits to us */
170#define ITE_BITS_TO_NS(bits, sample_period) \
171((u32) ((bits) * ITE_BAUDRATE_DIVISOR * sample_period))
172
173/*
174 * n in RDCR produces a tolerance of +/- n * 6.25% around the center
175 * carrier frequency...
176 *
177 * From two limit frequencies, L (low) and H (high), we can get both the
178 * center frequency F = (L + H) / 2 and the variation from the center
179 * frequency A = (H - L) / (H + L). We can use this in order to honor the
180 * s_rx_carrier_range() call in ir-core. We'll suppose that any request
181 * setting L=0 means we must shut down the demodulator.
182 */
183#define ITE_RXDCR_PER_10000_STEP 625
184
185/* high speed carrier freq values */
186#define ITE_CFQ_400		0x03
187#define ITE_CFQ_450		0x08
188#define ITE_CFQ_480		0x0b
189#define ITE_CFQ_500		0x0d
190
191/* values for pulse widths */
192#define ITE_TXMPW_A		0x02
193#define ITE_TXMPW_B		0x03
194#define ITE_TXMPW_C		0x04
195#define ITE_TXMPW_D		0x05
196#define ITE_TXMPW_E		0x06
197
198/* values for demodulator carrier range allowance */
199#define ITE_RXDCR_DEFAULT	0x01	/* default carrier range */
200#define ITE_RXDCR_MAX		0x07	/* default carrier range */
201
202/* DR TX bits */
203#define ITE_TX_PULSE		0x00
204#define ITE_TX_SPACE		0x80
205#define ITE_TX_MAX_RLE		0x80
206#define ITE_TX_RLE_MASK		0x7f
207
208/*
209 * IT8712F
210 *
211 * hardware data obtained from:
212 *
213 * IT8712F
214 * Environment Control – Low Pin Count Input / Output
215 * (EC - LPC I/O)
216 * Preliminary Specification V0. 81
217 */
218
219/* register offsets */
220#define IT87_DR		0x00	/* data register */
221#define IT87_IER	0x01	/* interrupt enable register */
222#define IT87_RCR	0x02	/* receiver control register */
223#define IT87_TCR1	0x03	/* transmitter control register 1 */
224#define IT87_TCR2	0x04	/* transmitter control register 2 */
225#define IT87_TSR	0x05	/* transmitter status register */
226#define IT87_RSR	0x06	/* receiver status register */
227#define IT87_BDLR	0x05	/* baud rate divisor low byte register */
228#define IT87_BDHR	0x06	/* baud rate divisor high byte register */
229#define IT87_IIR	0x07	/* interrupt identification register */
230
231#define IT87_IOREG_LENGTH 0x08	/* length of register file */
232
233/* IER bits */
234#define IT87_TLDLIE	0x01	/* transmitter low data interrupt enable */
235#define IT87_RDAIE	0x02	/* receiver data available interrupt enable */
236#define IT87_RFOIE	0x04	/* receiver FIFO overrun interrupt enable */
237#define IT87_IEC	0x08	/* interrupt enable control */
238#define IT87_BR		0x10	/* baud rate register enable */
239#define IT87_RESET	0x20	/* reset */
240
241/* RCR bits */
242#define IT87_RXDCR	0x07	/* receiver demodulation carrier range mask */
243#define IT87_RXACT	0x08	/* receiver active */
244#define IT87_RXEND	0x10	/* receiver demodulation enable */
245#define IT87_RXEN	0x20	/* receiver enable */
246#define IT87_HCFS	0x40	/* high-speed carrier frequency select */
247#define IT87_RDWOS	0x80	/* receiver data without sync */
248
249/* TCR1 bits */
250#define IT87_TXMPM	0x03	/* transmitter modulation pulse mode mask */
251#define IT87_TXMPM_DEFAULT 0x00	/* modulation pulse mode default */
252#define IT87_TXENDF	0x04	/* transmitter deferral */
253#define IT87_TXRLE	0x08	/* transmitter run length enable */
254#define IT87_FIFOTL	0x30	/* FIFO level threshold mask */
255#define IT87_FIFOTL_DEFAULT 0x20	/* FIFO level threshold default
256					 * 0x00 -> 1, 0x10 -> 7, 0x20 -> 17,
257					 * 0x30 -> 25 */
258#define IT87_ILE	0x40	/* internal loopback enable */
259#define IT87_FIFOCLR	0x80	/* FIFO clear bit */
260
261/* TCR2 bits */
262#define IT87_TXMPW	0x07	/* transmitter modulation pulse width mask */
263#define IT87_TXMPW_DEFAULT 0x04	/* default modulation pulse width */
264#define IT87_CFQ	0xf8	/* carrier frequency mask */
265#define IT87_CFQ_SHIFT	3	/* carrier frequency bit shift */
266
267/* TSR bits */
268#define IT87_TXFBC	0x3f	/* transmitter FIFO byte count mask */
269
270/* RSR bits */
271#define IT87_RXFBC	0x3f	/* receiver FIFO byte count mask */
272#define IT87_RXFTO	0x80	/* receiver FIFO time-out */
273
274/* IIR bits */
275#define IT87_IP		0x01	/* interrupt pending */
276#define IT87_II		0x06	/* interrupt identification mask */
277#define IT87_II_NOINT	0x00	/* no interrupt */
278#define IT87_II_TXLDL	0x02	/* transmitter low data level */
279#define IT87_II_RXDS	0x04	/* receiver data stored */
280#define IT87_II_RXFO	0x06	/* receiver FIFO overrun */
281
282/*
283 * IT8512E/F
284 *
285 * Hardware data obtained from:
286 *
287 * IT8512E/F
288 * Embedded Controller
289 * Preliminary Specification V0.4.1
290 *
291 * Note that the CIR registers are not directly available to the host, because
292 * they only are accessible to the integrated microcontroller. Thus, in order
293 * use it, some kind of bridging is required. As the bridging may depend on
294 * the controller firmware in use, we are going to use the PNP ID in order to
295 * determine the strategy and ports available. See after these generic
296 * IT8512E/F register definitions for register definitions for those
297 * strategies.
298 */
299
300/* register offsets */
301#define IT85_C0DR	0x00	/* data register */
302#define IT85_C0MSTCR	0x01	/* master control register */
303#define IT85_C0IER	0x02	/* interrupt enable register */
304#define IT85_C0IIR	0x03	/* interrupt identification register */
305#define IT85_C0CFR	0x04	/* carrier frequency register */
306#define IT85_C0RCR	0x05	/* receiver control register */
307#define IT85_C0TCR	0x06	/* transmitter control register */
308#define IT85_C0SCK	0x07	/* slow clock control register */
309#define IT85_C0BDLR	0x08	/* baud rate divisor low byte register */
310#define IT85_C0BDHR	0x09	/* baud rate divisor high byte register */
311#define IT85_C0TFSR	0x0a	/* transmitter FIFO status register */
312#define IT85_C0RFSR	0x0b	/* receiver FIFO status register */
313#define IT85_C0WCL	0x0d	/* wakeup code length register */
314#define IT85_C0WCR	0x0e	/* wakeup code read/write register */
315#define IT85_C0WPS	0x0f	/* wakeup power control/status register */
316
317#define IT85_IOREG_LENGTH 0x10	/* length of register file */
318
319/* C0MSTCR bits */
320#define IT85_RESET	0x01	/* reset */
321#define IT85_FIFOCLR	0x02	/* FIFO clear bit */
322#define IT85_FIFOTL	0x0c	/* FIFO level threshold mask */
323#define IT85_FIFOTL_DEFAULT 0x08	/* FIFO level threshold default
324					 * 0x00 -> 1, 0x04 -> 7, 0x08 -> 17,
325					 * 0x0c -> 25 */
326#define IT85_ILE	0x10	/* internal loopback enable */
327#define IT85_ILSEL	0x20	/* internal loopback select */
328
329/* C0IER bits */
330#define IT85_TLDLIE	0x01	/* TX low data level interrupt enable */
331#define IT85_RDAIE	0x02	/* RX data available interrupt enable */
332#define IT85_RFOIE	0x04	/* RX FIFO overrun interrupt enable */
333#define IT85_IEC	0x80	/* interrupt enable function control */
334
335/* C0IIR bits */
336#define IT85_TLDLI	0x01	/* transmitter low data level interrupt */
337#define IT85_RDAI	0x02	/* receiver data available interrupt */
338#define IT85_RFOI	0x04	/* receiver FIFO overrun interrupt */
339#define IT85_NIP	0x80	/* no interrupt pending */
340
341/* C0CFR bits */
342#define IT85_CFQ	0x1f	/* carrier frequency mask */
343#define IT85_HCFS	0x20	/* high speed carrier frequency select */
344
345/* C0RCR bits */
346#define IT85_RXDCR	0x07	/* receiver demodulation carrier range mask */
347#define IT85_RXACT	0x08	/* receiver active */
348#define IT85_RXEND	0x10	/* receiver demodulation enable */
349#define IT85_RDWOS	0x20	/* receiver data without sync */
350#define IT85_RXEN	0x80	/* receiver enable */
351
352/* C0TCR bits */
353#define IT85_TXMPW	0x07	/* transmitter modulation pulse width mask */
354#define IT85_TXMPW_DEFAULT 0x04	/* default modulation pulse width */
355#define IT85_TXMPM	0x18	/* transmitter modulation pulse mode mask */
356#define IT85_TXMPM_DEFAULT 0x00	/* modulation pulse mode default */
357#define IT85_TXENDF	0x20	/* transmitter deferral */
358#define IT85_TXRLE	0x40	/* transmitter run length enable */
359
360/* C0SCK bits */
361#define IT85_SCKS	0x01	/* slow clock select */
362#define IT85_TXDCKG	0x02	/* TXD clock gating */
363#define IT85_DLL1P8E	0x04	/* DLL 1.8432M enable */
364#define IT85_DLLTE	0x08	/* DLL test enable */
365#define IT85_BRCM	0x70	/* baud rate count mode */
366#define IT85_DLLOCK	0x80	/* DLL lock */
367
368/* C0TFSR bits */
369#define IT85_TXFBC	0x3f	/* transmitter FIFO count mask */
370
371/* C0RFSR bits */
372#define IT85_RXFBC	0x3f	/* receiver FIFO count mask */
373#define IT85_RXFTO	0x80	/* receiver FIFO time-out */
374
375/* C0WCL bits */
376#define IT85_WCL	0x3f	/* wakeup code length mask */
377
378/* C0WPS bits */
379#define IT85_CIRPOSIE	0x01	/* power on/off status interrupt enable */
380#define IT85_CIRPOIS	0x02	/* power on/off interrupt status */
381#define IT85_CIRPOII	0x04	/* power on/off interrupt identification */
382#define IT85_RCRST	0x10	/* wakeup code reading counter reset bit */
383#define IT85_WCRST	0x20	/* wakeup code writing counter reset bit */
384
385/*
386 * ITE8708
387 *
388 * Hardware data obtained from hacked driver for IT8512 in this forum post:
389 *
390 *  http://ubuntuforums.org/showthread.php?t=1028640
391 *
392 * Although there's no official documentation for that driver, analysis would
393 * suggest that it maps the 16 registers of IT8512 onto two 8-register banks,
394 * selectable by a single bank-select bit that's mapped onto both banks. The
395 * IT8512 registers are mapped in a different order, so that the first bank
396 * maps the ones that are used more often, and two registers that share a
397 * reserved high-order bit are placed at the same offset in both banks in
398 * order to reuse the reserved bit as the bank select bit.
399 */
400
401/* register offsets */
402
403/* mapped onto both banks */
404#define IT8708_BANKSEL	0x07	/* bank select register */
405#define IT8708_HRAE	0x80	/* high registers access enable */
406
407/* mapped onto the low bank */
408#define IT8708_C0DR	0x00	/* data register */
409#define IT8708_C0MSTCR	0x01	/* master control register */
410#define IT8708_C0IER	0x02	/* interrupt enable register */
411#define IT8708_C0IIR	0x03	/* interrupt identification register */
412#define IT8708_C0RFSR	0x04	/* receiver FIFO status register */
413#define IT8708_C0RCR	0x05	/* receiver control register */
414#define IT8708_C0TFSR	0x06	/* transmitter FIFO status register */
415#define IT8708_C0TCR	0x07	/* transmitter control register */
416
417/* mapped onto the high bank */
418#define IT8708_C0BDLR	0x01	/* baud rate divisor low byte register */
419#define IT8708_C0BDHR	0x02	/* baud rate divisor high byte register */
420#define IT8708_C0CFR	0x04	/* carrier frequency register */
421
422/* registers whose bank mapping we don't know, since they weren't being used
423 * in the hacked driver... most probably they belong to the high bank too,
424 * since they fit in the holes the other registers leave */
425#define IT8708_C0SCK	0x03	/* slow clock control register */
426#define IT8708_C0WCL	0x05	/* wakeup code length register */
427#define IT8708_C0WCR	0x06	/* wakeup code read/write register */
428#define IT8708_C0WPS	0x07	/* wakeup power control/status register */
429
430#define IT8708_IOREG_LENGTH 0x08	/* length of register file */
431
432/* two more registers that are defined in the hacked driver, but can't be
433 * found in the data sheets; no idea what they are or how they are accessed,
434 * since the hacked driver doesn't seem to use them */
435#define IT8708_CSCRR	0x00
436#define IT8708_CGPINTR	0x01
437
438/* CSCRR bits */
439#define IT8708_CSCRR_SCRB 0x3f
440#define IT8708_CSCRR_PM	0x80
441
442/* CGPINTR bits */
443#define IT8708_CGPINT	0x01
444
445/*
446 * ITE8709
447 *
448 * Hardware interfacing data obtained from the original lirc_ite8709 driver.
449 * Verbatim from its sources:
450 *
451 * The ITE8709 device seems to be the combination of IT8512 superIO chip and
452 * a specific firmware running on the IT8512's embedded micro-controller.
453 * In addition of the embedded micro-controller, the IT8512 chip contains a
454 * CIR module and several other modules. A few modules are directly accessible
455 * by the host CPU, but most of them are only accessible by the
456 * micro-controller. The CIR module is only accessible by the
457 * micro-controller.
458 *
459 * The battery-backed SRAM module is accessible by the host CPU and the
460 * micro-controller. So one of the MC's firmware role is to act as a bridge
461 * between the host CPU and the CIR module. The firmware implements a kind of
462 * communication protocol using the SRAM module as a shared memory. The IT8512
463 * specification is publicly available on ITE's web site, but the
464 * communication protocol is not, so it was reverse-engineered.
465 */
466
467/* register offsets */
468#define IT8709_RAM_IDX	0x00	/* index into the SRAM module bytes */
469#define IT8709_RAM_VAL	0x01	/* read/write data to the indexed byte */
470
471#define IT8709_IOREG_LENGTH 0x02	/* length of register file */
472
473/* register offsets inside the SRAM module */
474#define IT8709_MODE	0x1a	/* request/ack byte */
475#define IT8709_REG_IDX	0x1b	/* index of the CIR register to access */
476#define IT8709_REG_VAL	0x1c	/* value read/to be written */
477#define IT8709_IIR	0x1e	/* interrupt identification register */
478#define IT8709_RFSR	0x1f	/* receiver FIFO status register */
479#define IT8709_FIFO	0x20	/* start of in RAM RX FIFO copy */
480
481/* MODE values */
482#define IT8709_IDLE	0x00
483#define IT8709_WRITE	0x01
484#define IT8709_READ	0x02
485