xref: /openbmc/linux/arch/arm/mach-pxa/mfp-pxa2xx.c (revision c059ee9d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/arch/arm/mach-pxa/mfp-pxa2xx.c
4  *
5  *  PXA2xx pin mux configuration support
6  *
7  *  The GPIOs on PXA2xx can be configured as one of many alternate
8  *  functions, this is by concept samilar to the MFP configuration
9  *  on PXA3xx,  what's more important, the low power pin state and
10  *  wakeup detection are also supported by the same framework.
11  */
12 #include <linux/gpio.h>
13 #include <linux/gpio-pxa.h>
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/io.h>
18 #include <linux/syscore_ops.h>
19 #include <linux/soc/pxa/cpu.h>
20 
21 #include "pxa2xx-regs.h"
22 #include "mfp-pxa2xx.h"
23 
24 #include "generic.h"
25 
26 #define PGSR(x)		__REG2(0x40F00020, (x) << 2)
27 #define __GAFR(u, x)	__REG2((u) ? 0x40E00058 : 0x40E00054, (x) << 3)
28 #define GAFR_L(x)	__GAFR(0, x)
29 #define GAFR_U(x)	__GAFR(1, x)
30 
31 #define BANK_OFF(n)	(((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
32 #define GPLR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5))
33 #define GPDR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x0c)
34 #define GPSR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x18)
35 #define GPCR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x24)
36 
37 #define PWER_WE35	(1 << 24)
38 
39 struct gpio_desc {
40 	unsigned	valid		: 1;
41 	unsigned	can_wakeup	: 1;
42 	unsigned	keypad_gpio	: 1;
43 	unsigned	dir_inverted	: 1;
44 	unsigned int	mask; /* bit mask in PWER or PKWR */
45 	unsigned int	mux_mask; /* bit mask of muxed gpio bits, 0 if no mux */
46 	unsigned long	config;
47 };
48 
49 static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
50 
51 static unsigned long gpdr_lpm[4];
52 
53 static int __mfp_config_gpio(unsigned gpio, unsigned long c)
54 {
55 	unsigned long gafr, mask = GPIO_bit(gpio);
56 	int bank = gpio_to_bank(gpio);
57 	int uorl = !!(gpio & 0x10); /* GAFRx_U or GAFRx_L ? */
58 	int shft = (gpio & 0xf) << 1;
59 	int fn = MFP_AF(c);
60 	int is_out = (c & MFP_DIR_OUT) ? 1 : 0;
61 
62 	if (fn > 3)
63 		return -EINVAL;
64 
65 	/* alternate function and direction at run-time */
66 	gafr = (uorl == 0) ? GAFR_L(bank) : GAFR_U(bank);
67 	gafr = (gafr & ~(0x3 << shft)) | (fn << shft);
68 
69 	if (uorl == 0)
70 		GAFR_L(bank) = gafr;
71 	else
72 		GAFR_U(bank) = gafr;
73 
74 	if (is_out ^ gpio_desc[gpio].dir_inverted)
75 		GPDR(gpio) |= mask;
76 	else
77 		GPDR(gpio) &= ~mask;
78 
79 	/* alternate function and direction at low power mode */
80 	switch (c & MFP_LPM_STATE_MASK) {
81 	case MFP_LPM_DRIVE_HIGH:
82 		PGSR(bank) |= mask;
83 		is_out = 1;
84 		break;
85 	case MFP_LPM_DRIVE_LOW:
86 		PGSR(bank) &= ~mask;
87 		is_out = 1;
88 		break;
89 	case MFP_LPM_INPUT:
90 	case MFP_LPM_DEFAULT:
91 		break;
92 	default:
93 		/* warning and fall through, treat as MFP_LPM_DEFAULT */
94 		pr_warn("%s: GPIO%d: unsupported low power mode\n",
95 			__func__, gpio);
96 		break;
97 	}
98 
99 	if (is_out ^ gpio_desc[gpio].dir_inverted)
100 		gpdr_lpm[bank] |= mask;
101 	else
102 		gpdr_lpm[bank] &= ~mask;
103 
104 	/* give early warning if MFP_LPM_CAN_WAKEUP is set on the
105 	 * configurations of those pins not able to wakeup
106 	 */
107 	if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
108 		pr_warn("%s: GPIO%d unable to wakeup\n", __func__, gpio);
109 		return -EINVAL;
110 	}
111 
112 	if ((c & MFP_LPM_CAN_WAKEUP) && is_out) {
113 		pr_warn("%s: output GPIO%d unable to wakeup\n", __func__, gpio);
114 		return -EINVAL;
115 	}
116 
117 	return 0;
118 }
119 
120 static inline int __mfp_validate(int mfp)
121 {
122 	int gpio = mfp_to_gpio(mfp);
123 
124 	if ((mfp > MFP_PIN_GPIO127) || !gpio_desc[gpio].valid) {
125 		pr_warn("%s: GPIO%d is invalid pin\n", __func__, gpio);
126 		return -1;
127 	}
128 
129 	return gpio;
130 }
131 
132 void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
133 {
134 	unsigned long flags;
135 	unsigned long *c;
136 	int i, gpio;
137 
138 	for (i = 0, c = mfp_cfgs; i < num; i++, c++) {
139 
140 		gpio = __mfp_validate(MFP_PIN(*c));
141 		if (gpio < 0)
142 			continue;
143 
144 		local_irq_save(flags);
145 
146 		gpio_desc[gpio].config = *c;
147 		__mfp_config_gpio(gpio, *c);
148 
149 		local_irq_restore(flags);
150 	}
151 }
152 
153 void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
154 {
155 	unsigned long flags, c;
156 	int gpio;
157 
158 	gpio = __mfp_validate(mfp);
159 	if (gpio < 0)
160 		return;
161 
162 	local_irq_save(flags);
163 
164 	c = gpio_desc[gpio].config;
165 	c = (c & ~MFP_LPM_STATE_MASK) | lpm;
166 	__mfp_config_gpio(gpio, c);
167 
168 	local_irq_restore(flags);
169 }
170 
171 int gpio_set_wake(unsigned int gpio, unsigned int on)
172 {
173 	struct gpio_desc *d;
174 	unsigned long c, mux_taken;
175 
176 	if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
177 		return -EINVAL;
178 
179 	d = &gpio_desc[gpio];
180 	c = d->config;
181 
182 	if (!d->valid)
183 		return -EINVAL;
184 
185 	/* Allow keypad GPIOs to wakeup system when
186 	 * configured as generic GPIOs.
187 	 */
188 	if (d->keypad_gpio && (MFP_AF(d->config) == 0) &&
189 	    (d->config & MFP_LPM_CAN_WAKEUP)) {
190 		if (on)
191 			PKWR |= d->mask;
192 		else
193 			PKWR &= ~d->mask;
194 		return 0;
195 	}
196 
197 	mux_taken = (PWER & d->mux_mask) & (~d->mask);
198 	if (on && mux_taken)
199 		return -EBUSY;
200 
201 	if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
202 		if (on) {
203 			PWER = (PWER & ~d->mux_mask) | d->mask;
204 
205 			if (c & MFP_LPM_EDGE_RISE)
206 				PRER |= d->mask;
207 			else
208 				PRER &= ~d->mask;
209 
210 			if (c & MFP_LPM_EDGE_FALL)
211 				PFER |= d->mask;
212 			else
213 				PFER &= ~d->mask;
214 		} else {
215 			PWER &= ~d->mask;
216 			PRER &= ~d->mask;
217 			PFER &= ~d->mask;
218 		}
219 	}
220 	return 0;
221 }
222 
223 #ifdef CONFIG_PXA25x
224 static void __init pxa25x_mfp_init(void)
225 {
226 	int i;
227 
228 	/* running before pxa_gpio_probe() */
229 #ifdef CONFIG_CPU_PXA26x
230 	pxa_last_gpio = 89;
231 #else
232 	pxa_last_gpio = 84;
233 #endif
234 	for (i = 0; i <= pxa_last_gpio; i++)
235 		gpio_desc[i].valid = 1;
236 
237 	for (i = 0; i <= 15; i++) {
238 		gpio_desc[i].can_wakeup = 1;
239 		gpio_desc[i].mask = GPIO_bit(i);
240 	}
241 
242 	/* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
243 	 * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
244 	 */
245 	for (i = 86; i <= pxa_last_gpio; i++)
246 		gpio_desc[i].dir_inverted = 1;
247 }
248 #else
249 static inline void pxa25x_mfp_init(void) {}
250 #endif /* CONFIG_PXA25x */
251 
252 #ifdef CONFIG_PXA27x
253 static int pxa27x_pkwr_gpio[] = {
254 	13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
255 	95, 96, 97, 98, 99, 100, 101, 102
256 };
257 
258 int keypad_set_wake(unsigned int on)
259 {
260 	unsigned int i, gpio, mask = 0;
261 	struct gpio_desc *d;
262 
263 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
264 
265 		gpio = pxa27x_pkwr_gpio[i];
266 		d = &gpio_desc[gpio];
267 
268 		/* skip if configured as generic GPIO */
269 		if (MFP_AF(d->config) == 0)
270 			continue;
271 
272 		if (d->config & MFP_LPM_CAN_WAKEUP)
273 			mask |= gpio_desc[gpio].mask;
274 	}
275 
276 	if (on)
277 		PKWR |= mask;
278 	else
279 		PKWR &= ~mask;
280 	return 0;
281 }
282 
283 #define PWER_WEMUX2_GPIO38	(1 << 16)
284 #define PWER_WEMUX2_GPIO53	(2 << 16)
285 #define PWER_WEMUX2_GPIO40	(3 << 16)
286 #define PWER_WEMUX2_GPIO36	(4 << 16)
287 #define PWER_WEMUX2_MASK	(7 << 16)
288 #define PWER_WEMUX3_GPIO31	(1 << 19)
289 #define PWER_WEMUX3_GPIO113	(2 << 19)
290 #define PWER_WEMUX3_MASK	(3 << 19)
291 
292 #define INIT_GPIO_DESC_MUXED(mux, gpio)				\
293 do {								\
294 	gpio_desc[(gpio)].can_wakeup = 1;			\
295 	gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;	\
296 	gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;	\
297 } while (0)
298 
299 static void __init pxa27x_mfp_init(void)
300 {
301 	int i, gpio;
302 
303 	pxa_last_gpio = 120;	/* running before pxa_gpio_probe() */
304 	for (i = 0; i <= pxa_last_gpio; i++) {
305 		/* skip GPIO2, 5, 6, 7, 8, they are not
306 		 * valid pins allow configuration
307 		 */
308 		if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
309 			continue;
310 
311 		gpio_desc[i].valid = 1;
312 	}
313 
314 	/* Keypad GPIOs */
315 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
316 		gpio = pxa27x_pkwr_gpio[i];
317 		gpio_desc[gpio].can_wakeup = 1;
318 		gpio_desc[gpio].keypad_gpio = 1;
319 		gpio_desc[gpio].mask = 1 << i;
320 	}
321 
322 	/* Overwrite GPIO13 as a PWER wakeup source */
323 	for (i = 0; i <= 15; i++) {
324 		/* skip GPIO2, 5, 6, 7, 8 */
325 		if (GPIO_bit(i) & 0x1e4)
326 			continue;
327 
328 		gpio_desc[i].can_wakeup = 1;
329 		gpio_desc[i].mask = GPIO_bit(i);
330 	}
331 
332 	gpio_desc[35].can_wakeup = 1;
333 	gpio_desc[35].mask = PWER_WE35;
334 
335 	INIT_GPIO_DESC_MUXED(WEMUX3, 31);
336 	INIT_GPIO_DESC_MUXED(WEMUX3, 113);
337 	INIT_GPIO_DESC_MUXED(WEMUX2, 38);
338 	INIT_GPIO_DESC_MUXED(WEMUX2, 53);
339 	INIT_GPIO_DESC_MUXED(WEMUX2, 40);
340 	INIT_GPIO_DESC_MUXED(WEMUX2, 36);
341 }
342 #else
343 static inline void pxa27x_mfp_init(void) {}
344 #endif /* CONFIG_PXA27x */
345 
346 #ifdef CONFIG_PM
347 static unsigned long saved_gafr[2][4];
348 static unsigned long saved_gpdr[4];
349 static unsigned long saved_gplr[4];
350 static unsigned long saved_pgsr[4];
351 
352 static int pxa2xx_mfp_suspend(void)
353 {
354 	int i;
355 
356 	/* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
357 	for (i = 0; i < pxa_last_gpio; i++) {
358 		if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
359 		    (GPDR(i) & GPIO_bit(i))) {
360 			if (GPLR(i) & GPIO_bit(i))
361 				PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
362 			else
363 				PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
364 		}
365 	}
366 
367 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
368 		saved_gafr[0][i] = GAFR_L(i);
369 		saved_gafr[1][i] = GAFR_U(i);
370 		saved_gpdr[i] = GPDR(i * 32);
371 		saved_gplr[i] = GPLR(i * 32);
372 		saved_pgsr[i] = PGSR(i);
373 
374 		GPSR(i * 32) = PGSR(i);
375 		GPCR(i * 32) = ~PGSR(i);
376 	}
377 
378 	/* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
379 	for (i = 0; i < pxa_last_gpio; i++) {
380 		if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
381 		    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
382 		     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
383 			GPDR(i) |= GPIO_bit(i);
384 		else
385 			GPDR(i) &= ~GPIO_bit(i);
386 	}
387 
388 	return 0;
389 }
390 
391 static void pxa2xx_mfp_resume(void)
392 {
393 	int i;
394 
395 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
396 		GAFR_L(i) = saved_gafr[0][i];
397 		GAFR_U(i) = saved_gafr[1][i];
398 		GPSR(i * 32) = saved_gplr[i];
399 		GPCR(i * 32) = ~saved_gplr[i];
400 		GPDR(i * 32) = saved_gpdr[i];
401 		PGSR(i) = saved_pgsr[i];
402 	}
403 	PSSR = PSSR_RDH | PSSR_PH;
404 }
405 #else
406 #define pxa2xx_mfp_suspend	NULL
407 #define pxa2xx_mfp_resume	NULL
408 #endif
409 
410 struct syscore_ops pxa2xx_mfp_syscore_ops = {
411 	.suspend	= pxa2xx_mfp_suspend,
412 	.resume		= pxa2xx_mfp_resume,
413 };
414 
415 static int __init pxa2xx_mfp_init(void)
416 {
417 	int i;
418 
419 	if (!cpu_is_pxa2xx())
420 		return 0;
421 
422 	if (cpu_is_pxa25x())
423 		pxa25x_mfp_init();
424 
425 	if (cpu_is_pxa27x())
426 		pxa27x_mfp_init();
427 
428 	/* clear RDH bit to enable GPIO receivers after reset/sleep exit */
429 	PSSR = PSSR_RDH;
430 
431 	/* initialize gafr_run[], pgsr_lpm[] from existing values */
432 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
433 		gpdr_lpm[i] = GPDR(i * 32);
434 
435 	return 0;
436 }
437 postcore_initcall(pxa2xx_mfp_init);
438