xref: /openbmc/linux/arch/arm/mach-pxa/mfp-pxa2xx.c (revision b830f94f)
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 
20 #include <mach/pxa2xx-regs.h>
21 #include "mfp-pxa2xx.h"
22 
23 #include "generic.h"
24 
25 #define PGSR(x)		__REG2(0x40F00020, (x) << 2)
26 #define __GAFR(u, x)	__REG2((u) ? 0x40E00058 : 0x40E00054, (x) << 3)
27 #define GAFR_L(x)	__GAFR(0, x)
28 #define GAFR_U(x)	__GAFR(1, x)
29 
30 #define BANK_OFF(n)	(((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
31 #define GPLR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5))
32 #define GPDR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x0c)
33 #define GPSR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x18)
34 #define GPCR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x24)
35 
36 #define PWER_WE35	(1 << 24)
37 
38 struct gpio_desc {
39 	unsigned	valid		: 1;
40 	unsigned	can_wakeup	: 1;
41 	unsigned	keypad_gpio	: 1;
42 	unsigned	dir_inverted	: 1;
43 	unsigned int	mask; /* bit mask in PWER or PKWR */
44 	unsigned int	mux_mask; /* bit mask of muxed gpio bits, 0 if no mux */
45 	unsigned long	config;
46 };
47 
48 static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
49 
50 static unsigned long gpdr_lpm[4];
51 
52 static int __mfp_config_gpio(unsigned gpio, unsigned long c)
53 {
54 	unsigned long gafr, mask = GPIO_bit(gpio);
55 	int bank = gpio_to_bank(gpio);
56 	int uorl = !!(gpio & 0x10); /* GAFRx_U or GAFRx_L ? */
57 	int shft = (gpio & 0xf) << 1;
58 	int fn = MFP_AF(c);
59 	int is_out = (c & MFP_DIR_OUT) ? 1 : 0;
60 
61 	if (fn > 3)
62 		return -EINVAL;
63 
64 	/* alternate function and direction at run-time */
65 	gafr = (uorl == 0) ? GAFR_L(bank) : GAFR_U(bank);
66 	gafr = (gafr & ~(0x3 << shft)) | (fn << shft);
67 
68 	if (uorl == 0)
69 		GAFR_L(bank) = gafr;
70 	else
71 		GAFR_U(bank) = gafr;
72 
73 	if (is_out ^ gpio_desc[gpio].dir_inverted)
74 		GPDR(gpio) |= mask;
75 	else
76 		GPDR(gpio) &= ~mask;
77 
78 	/* alternate function and direction at low power mode */
79 	switch (c & MFP_LPM_STATE_MASK) {
80 	case MFP_LPM_DRIVE_HIGH:
81 		PGSR(bank) |= mask;
82 		is_out = 1;
83 		break;
84 	case MFP_LPM_DRIVE_LOW:
85 		PGSR(bank) &= ~mask;
86 		is_out = 1;
87 		break;
88 	case MFP_LPM_INPUT:
89 	case MFP_LPM_DEFAULT:
90 		break;
91 	default:
92 		/* warning and fall through, treat as MFP_LPM_DEFAULT */
93 		pr_warn("%s: GPIO%d: unsupported low power mode\n",
94 			__func__, gpio);
95 		break;
96 	}
97 
98 	if (is_out ^ gpio_desc[gpio].dir_inverted)
99 		gpdr_lpm[bank] |= mask;
100 	else
101 		gpdr_lpm[bank] &= ~mask;
102 
103 	/* give early warning if MFP_LPM_CAN_WAKEUP is set on the
104 	 * configurations of those pins not able to wakeup
105 	 */
106 	if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
107 		pr_warn("%s: GPIO%d unable to wakeup\n", __func__, gpio);
108 		return -EINVAL;
109 	}
110 
111 	if ((c & MFP_LPM_CAN_WAKEUP) && is_out) {
112 		pr_warn("%s: output GPIO%d unable to wakeup\n", __func__, gpio);
113 		return -EINVAL;
114 	}
115 
116 	return 0;
117 }
118 
119 static inline int __mfp_validate(int mfp)
120 {
121 	int gpio = mfp_to_gpio(mfp);
122 
123 	if ((mfp > MFP_PIN_GPIO127) || !gpio_desc[gpio].valid) {
124 		pr_warn("%s: GPIO%d is invalid pin\n", __func__, gpio);
125 		return -1;
126 	}
127 
128 	return gpio;
129 }
130 
131 void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
132 {
133 	unsigned long flags;
134 	unsigned long *c;
135 	int i, gpio;
136 
137 	for (i = 0, c = mfp_cfgs; i < num; i++, c++) {
138 
139 		gpio = __mfp_validate(MFP_PIN(*c));
140 		if (gpio < 0)
141 			continue;
142 
143 		local_irq_save(flags);
144 
145 		gpio_desc[gpio].config = *c;
146 		__mfp_config_gpio(gpio, *c);
147 
148 		local_irq_restore(flags);
149 	}
150 }
151 
152 void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
153 {
154 	unsigned long flags, c;
155 	int gpio;
156 
157 	gpio = __mfp_validate(mfp);
158 	if (gpio < 0)
159 		return;
160 
161 	local_irq_save(flags);
162 
163 	c = gpio_desc[gpio].config;
164 	c = (c & ~MFP_LPM_STATE_MASK) | lpm;
165 	__mfp_config_gpio(gpio, c);
166 
167 	local_irq_restore(flags);
168 }
169 
170 int gpio_set_wake(unsigned int gpio, unsigned int on)
171 {
172 	struct gpio_desc *d;
173 	unsigned long c, mux_taken;
174 
175 	if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
176 		return -EINVAL;
177 
178 	d = &gpio_desc[gpio];
179 	c = d->config;
180 
181 	if (!d->valid)
182 		return -EINVAL;
183 
184 	/* Allow keypad GPIOs to wakeup system when
185 	 * configured as generic GPIOs.
186 	 */
187 	if (d->keypad_gpio && (MFP_AF(d->config) == 0) &&
188 	    (d->config & MFP_LPM_CAN_WAKEUP)) {
189 		if (on)
190 			PKWR |= d->mask;
191 		else
192 			PKWR &= ~d->mask;
193 		return 0;
194 	}
195 
196 	mux_taken = (PWER & d->mux_mask) & (~d->mask);
197 	if (on && mux_taken)
198 		return -EBUSY;
199 
200 	if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
201 		if (on) {
202 			PWER = (PWER & ~d->mux_mask) | d->mask;
203 
204 			if (c & MFP_LPM_EDGE_RISE)
205 				PRER |= d->mask;
206 			else
207 				PRER &= ~d->mask;
208 
209 			if (c & MFP_LPM_EDGE_FALL)
210 				PFER |= d->mask;
211 			else
212 				PFER &= ~d->mask;
213 		} else {
214 			PWER &= ~d->mask;
215 			PRER &= ~d->mask;
216 			PFER &= ~d->mask;
217 		}
218 	}
219 	return 0;
220 }
221 
222 #ifdef CONFIG_PXA25x
223 static void __init pxa25x_mfp_init(void)
224 {
225 	int i;
226 
227 	/* running before pxa_gpio_probe() */
228 #ifdef CONFIG_CPU_PXA26x
229 	pxa_last_gpio = 89;
230 #else
231 	pxa_last_gpio = 84;
232 #endif
233 	for (i = 0; i <= pxa_last_gpio; i++)
234 		gpio_desc[i].valid = 1;
235 
236 	for (i = 0; i <= 15; i++) {
237 		gpio_desc[i].can_wakeup = 1;
238 		gpio_desc[i].mask = GPIO_bit(i);
239 	}
240 
241 	/* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
242 	 * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
243 	 */
244 	for (i = 86; i <= pxa_last_gpio; i++)
245 		gpio_desc[i].dir_inverted = 1;
246 }
247 #else
248 static inline void pxa25x_mfp_init(void) {}
249 #endif /* CONFIG_PXA25x */
250 
251 #ifdef CONFIG_PXA27x
252 static int pxa27x_pkwr_gpio[] = {
253 	13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
254 	95, 96, 97, 98, 99, 100, 101, 102
255 };
256 
257 int keypad_set_wake(unsigned int on)
258 {
259 	unsigned int i, gpio, mask = 0;
260 	struct gpio_desc *d;
261 
262 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
263 
264 		gpio = pxa27x_pkwr_gpio[i];
265 		d = &gpio_desc[gpio];
266 
267 		/* skip if configured as generic GPIO */
268 		if (MFP_AF(d->config) == 0)
269 			continue;
270 
271 		if (d->config & MFP_LPM_CAN_WAKEUP)
272 			mask |= gpio_desc[gpio].mask;
273 	}
274 
275 	if (on)
276 		PKWR |= mask;
277 	else
278 		PKWR &= ~mask;
279 	return 0;
280 }
281 
282 #define PWER_WEMUX2_GPIO38	(1 << 16)
283 #define PWER_WEMUX2_GPIO53	(2 << 16)
284 #define PWER_WEMUX2_GPIO40	(3 << 16)
285 #define PWER_WEMUX2_GPIO36	(4 << 16)
286 #define PWER_WEMUX2_MASK	(7 << 16)
287 #define PWER_WEMUX3_GPIO31	(1 << 19)
288 #define PWER_WEMUX3_GPIO113	(2 << 19)
289 #define PWER_WEMUX3_MASK	(3 << 19)
290 
291 #define INIT_GPIO_DESC_MUXED(mux, gpio)				\
292 do {								\
293 	gpio_desc[(gpio)].can_wakeup = 1;			\
294 	gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;	\
295 	gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;	\
296 } while (0)
297 
298 static void __init pxa27x_mfp_init(void)
299 {
300 	int i, gpio;
301 
302 	pxa_last_gpio = 120;	/* running before pxa_gpio_probe() */
303 	for (i = 0; i <= pxa_last_gpio; i++) {
304 		/* skip GPIO2, 5, 6, 7, 8, they are not
305 		 * valid pins allow configuration
306 		 */
307 		if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
308 			continue;
309 
310 		gpio_desc[i].valid = 1;
311 	}
312 
313 	/* Keypad GPIOs */
314 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
315 		gpio = pxa27x_pkwr_gpio[i];
316 		gpio_desc[gpio].can_wakeup = 1;
317 		gpio_desc[gpio].keypad_gpio = 1;
318 		gpio_desc[gpio].mask = 1 << i;
319 	}
320 
321 	/* Overwrite GPIO13 as a PWER wakeup source */
322 	for (i = 0; i <= 15; i++) {
323 		/* skip GPIO2, 5, 6, 7, 8 */
324 		if (GPIO_bit(i) & 0x1e4)
325 			continue;
326 
327 		gpio_desc[i].can_wakeup = 1;
328 		gpio_desc[i].mask = GPIO_bit(i);
329 	}
330 
331 	gpio_desc[35].can_wakeup = 1;
332 	gpio_desc[35].mask = PWER_WE35;
333 
334 	INIT_GPIO_DESC_MUXED(WEMUX3, 31);
335 	INIT_GPIO_DESC_MUXED(WEMUX3, 113);
336 	INIT_GPIO_DESC_MUXED(WEMUX2, 38);
337 	INIT_GPIO_DESC_MUXED(WEMUX2, 53);
338 	INIT_GPIO_DESC_MUXED(WEMUX2, 40);
339 	INIT_GPIO_DESC_MUXED(WEMUX2, 36);
340 }
341 #else
342 static inline void pxa27x_mfp_init(void) {}
343 #endif /* CONFIG_PXA27x */
344 
345 #ifdef CONFIG_PM
346 static unsigned long saved_gafr[2][4];
347 static unsigned long saved_gpdr[4];
348 static unsigned long saved_gplr[4];
349 static unsigned long saved_pgsr[4];
350 
351 static int pxa2xx_mfp_suspend(void)
352 {
353 	int i;
354 
355 	/* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
356 	for (i = 0; i < pxa_last_gpio; i++) {
357 		if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
358 		    (GPDR(i) & GPIO_bit(i))) {
359 			if (GPLR(i) & GPIO_bit(i))
360 				PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
361 			else
362 				PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
363 		}
364 	}
365 
366 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
367 		saved_gafr[0][i] = GAFR_L(i);
368 		saved_gafr[1][i] = GAFR_U(i);
369 		saved_gpdr[i] = GPDR(i * 32);
370 		saved_gplr[i] = GPLR(i * 32);
371 		saved_pgsr[i] = PGSR(i);
372 
373 		GPSR(i * 32) = PGSR(i);
374 		GPCR(i * 32) = ~PGSR(i);
375 	}
376 
377 	/* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
378 	for (i = 0; i < pxa_last_gpio; i++) {
379 		if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
380 		    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
381 		     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
382 			GPDR(i) |= GPIO_bit(i);
383 		else
384 			GPDR(i) &= ~GPIO_bit(i);
385 	}
386 
387 	return 0;
388 }
389 
390 static void pxa2xx_mfp_resume(void)
391 {
392 	int i;
393 
394 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
395 		GAFR_L(i) = saved_gafr[0][i];
396 		GAFR_U(i) = saved_gafr[1][i];
397 		GPSR(i * 32) = saved_gplr[i];
398 		GPCR(i * 32) = ~saved_gplr[i];
399 		GPDR(i * 32) = saved_gpdr[i];
400 		PGSR(i) = saved_pgsr[i];
401 	}
402 	PSSR = PSSR_RDH | PSSR_PH;
403 }
404 #else
405 #define pxa2xx_mfp_suspend	NULL
406 #define pxa2xx_mfp_resume	NULL
407 #endif
408 
409 struct syscore_ops pxa2xx_mfp_syscore_ops = {
410 	.suspend	= pxa2xx_mfp_suspend,
411 	.resume		= pxa2xx_mfp_resume,
412 };
413 
414 static int __init pxa2xx_mfp_init(void)
415 {
416 	int i;
417 
418 	if (!cpu_is_pxa2xx())
419 		return 0;
420 
421 	if (cpu_is_pxa25x())
422 		pxa25x_mfp_init();
423 
424 	if (cpu_is_pxa27x())
425 		pxa27x_mfp_init();
426 
427 	/* clear RDH bit to enable GPIO receivers after reset/sleep exit */
428 	PSSR = PSSR_RDH;
429 
430 	/* initialize gafr_run[], pgsr_lpm[] from existing values */
431 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
432 		gpdr_lpm[i] = GPDR(i * 32);
433 
434 	return 0;
435 }
436 postcore_initcall(pxa2xx_mfp_init);
437