xref: /openbmc/linux/arch/arm/mach-pxa/mfp-pxa2xx.c (revision 84cc6674)
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 	pxa_last_gpio = 84;
230 	for (i = 0; i <= pxa_last_gpio; i++)
231 		gpio_desc[i].valid = 1;
232 
233 	for (i = 0; i <= 15; i++) {
234 		gpio_desc[i].can_wakeup = 1;
235 		gpio_desc[i].mask = GPIO_bit(i);
236 	}
237 
238 	/* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
239 	 * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
240 	 */
241 	for (i = 86; i <= pxa_last_gpio; i++)
242 		gpio_desc[i].dir_inverted = 1;
243 }
244 #else
245 static inline void pxa25x_mfp_init(void) {}
246 #endif /* CONFIG_PXA25x */
247 
248 #ifdef CONFIG_PXA27x
249 static int pxa27x_pkwr_gpio[] = {
250 	13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
251 	95, 96, 97, 98, 99, 100, 101, 102
252 };
253 
254 int keypad_set_wake(unsigned int on)
255 {
256 	unsigned int i, gpio, mask = 0;
257 	struct gpio_desc *d;
258 
259 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
260 
261 		gpio = pxa27x_pkwr_gpio[i];
262 		d = &gpio_desc[gpio];
263 
264 		/* skip if configured as generic GPIO */
265 		if (MFP_AF(d->config) == 0)
266 			continue;
267 
268 		if (d->config & MFP_LPM_CAN_WAKEUP)
269 			mask |= gpio_desc[gpio].mask;
270 	}
271 
272 	if (on)
273 		PKWR |= mask;
274 	else
275 		PKWR &= ~mask;
276 	return 0;
277 }
278 
279 #define PWER_WEMUX2_GPIO38	(1 << 16)
280 #define PWER_WEMUX2_GPIO53	(2 << 16)
281 #define PWER_WEMUX2_GPIO40	(3 << 16)
282 #define PWER_WEMUX2_GPIO36	(4 << 16)
283 #define PWER_WEMUX2_MASK	(7 << 16)
284 #define PWER_WEMUX3_GPIO31	(1 << 19)
285 #define PWER_WEMUX3_GPIO113	(2 << 19)
286 #define PWER_WEMUX3_MASK	(3 << 19)
287 
288 #define INIT_GPIO_DESC_MUXED(mux, gpio)				\
289 do {								\
290 	gpio_desc[(gpio)].can_wakeup = 1;			\
291 	gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;	\
292 	gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;	\
293 } while (0)
294 
295 static void __init pxa27x_mfp_init(void)
296 {
297 	int i, gpio;
298 
299 	pxa_last_gpio = 120;	/* running before pxa_gpio_probe() */
300 	for (i = 0; i <= pxa_last_gpio; i++) {
301 		/* skip GPIO2, 5, 6, 7, 8, they are not
302 		 * valid pins allow configuration
303 		 */
304 		if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
305 			continue;
306 
307 		gpio_desc[i].valid = 1;
308 	}
309 
310 	/* Keypad GPIOs */
311 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
312 		gpio = pxa27x_pkwr_gpio[i];
313 		gpio_desc[gpio].can_wakeup = 1;
314 		gpio_desc[gpio].keypad_gpio = 1;
315 		gpio_desc[gpio].mask = 1 << i;
316 	}
317 
318 	/* Overwrite GPIO13 as a PWER wakeup source */
319 	for (i = 0; i <= 15; i++) {
320 		/* skip GPIO2, 5, 6, 7, 8 */
321 		if (GPIO_bit(i) & 0x1e4)
322 			continue;
323 
324 		gpio_desc[i].can_wakeup = 1;
325 		gpio_desc[i].mask = GPIO_bit(i);
326 	}
327 
328 	gpio_desc[35].can_wakeup = 1;
329 	gpio_desc[35].mask = PWER_WE35;
330 
331 	INIT_GPIO_DESC_MUXED(WEMUX3, 31);
332 	INIT_GPIO_DESC_MUXED(WEMUX3, 113);
333 	INIT_GPIO_DESC_MUXED(WEMUX2, 38);
334 	INIT_GPIO_DESC_MUXED(WEMUX2, 53);
335 	INIT_GPIO_DESC_MUXED(WEMUX2, 40);
336 	INIT_GPIO_DESC_MUXED(WEMUX2, 36);
337 }
338 #else
339 static inline void pxa27x_mfp_init(void) {}
340 #endif /* CONFIG_PXA27x */
341 
342 #ifdef CONFIG_PM
343 static unsigned long saved_gafr[2][4];
344 static unsigned long saved_gpdr[4];
345 static unsigned long saved_gplr[4];
346 static unsigned long saved_pgsr[4];
347 
348 static int pxa2xx_mfp_suspend(void)
349 {
350 	int i;
351 
352 	/* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
353 	for (i = 0; i < pxa_last_gpio; i++) {
354 		if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
355 		    (GPDR(i) & GPIO_bit(i))) {
356 			if (GPLR(i) & GPIO_bit(i))
357 				PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
358 			else
359 				PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
360 		}
361 	}
362 
363 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
364 		saved_gafr[0][i] = GAFR_L(i);
365 		saved_gafr[1][i] = GAFR_U(i);
366 		saved_gpdr[i] = GPDR(i * 32);
367 		saved_gplr[i] = GPLR(i * 32);
368 		saved_pgsr[i] = PGSR(i);
369 
370 		GPSR(i * 32) = PGSR(i);
371 		GPCR(i * 32) = ~PGSR(i);
372 	}
373 
374 	/* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
375 	for (i = 0; i < pxa_last_gpio; i++) {
376 		if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
377 		    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
378 		     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
379 			GPDR(i) |= GPIO_bit(i);
380 		else
381 			GPDR(i) &= ~GPIO_bit(i);
382 	}
383 
384 	return 0;
385 }
386 
387 static void pxa2xx_mfp_resume(void)
388 {
389 	int i;
390 
391 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
392 		GAFR_L(i) = saved_gafr[0][i];
393 		GAFR_U(i) = saved_gafr[1][i];
394 		GPSR(i * 32) = saved_gplr[i];
395 		GPCR(i * 32) = ~saved_gplr[i];
396 		GPDR(i * 32) = saved_gpdr[i];
397 		PGSR(i) = saved_pgsr[i];
398 	}
399 	PSSR = PSSR_RDH | PSSR_PH;
400 }
401 #else
402 #define pxa2xx_mfp_suspend	NULL
403 #define pxa2xx_mfp_resume	NULL
404 #endif
405 
406 struct syscore_ops pxa2xx_mfp_syscore_ops = {
407 	.suspend	= pxa2xx_mfp_suspend,
408 	.resume		= pxa2xx_mfp_resume,
409 };
410 
411 static int __init pxa2xx_mfp_init(void)
412 {
413 	int i;
414 
415 	if (!cpu_is_pxa2xx())
416 		return 0;
417 
418 	if (cpu_is_pxa25x())
419 		pxa25x_mfp_init();
420 
421 	if (cpu_is_pxa27x())
422 		pxa27x_mfp_init();
423 
424 	/* clear RDH bit to enable GPIO receivers after reset/sleep exit */
425 	PSSR = PSSR_RDH;
426 
427 	/* initialize gafr_run[], pgsr_lpm[] from existing values */
428 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
429 		gpdr_lpm[i] = GPDR(i * 32);
430 
431 	return 0;
432 }
433 postcore_initcall(pxa2xx_mfp_init);
434