xref: /openbmc/linux/arch/arm/mach-pxa/mfp-pxa2xx.c (revision a9ae9c52)
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 #include "mfp-pxa27x.h"
24 
25 #include "generic.h"
26 
27 #define PGSR(x)		__REG2(0x40F00020, (x) << 2)
28 #define __GAFR(u, x)	__REG2((u) ? 0x40E00058 : 0x40E00054, (x) << 3)
29 #define GAFR_L(x)	__GAFR(0, x)
30 #define GAFR_U(x)	__GAFR(1, x)
31 
32 #define BANK_OFF(n)	(((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
33 #define GPLR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5))
34 #define GPDR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x0c)
35 #define GPSR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x18)
36 #define GPCR(x)		__REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x24)
37 
38 #define PWER_WE35	(1 << 24)
39 
40 struct gpio_desc {
41 	unsigned	valid		: 1;
42 	unsigned	can_wakeup	: 1;
43 	unsigned	keypad_gpio	: 1;
44 	unsigned	dir_inverted	: 1;
45 	unsigned int	mask; /* bit mask in PWER or PKWR */
46 	unsigned int	mux_mask; /* bit mask of muxed gpio bits, 0 if no mux */
47 	unsigned long	config;
48 };
49 
50 static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
51 
52 static unsigned long gpdr_lpm[4];
53 
__mfp_config_gpio(unsigned gpio,unsigned long c)54 static int __mfp_config_gpio(unsigned gpio, unsigned long c)
55 {
56 	unsigned long gafr, mask = GPIO_bit(gpio);
57 	int bank = gpio_to_bank(gpio);
58 	int uorl = !!(gpio & 0x10); /* GAFRx_U or GAFRx_L ? */
59 	int shft = (gpio & 0xf) << 1;
60 	int fn = MFP_AF(c);
61 	int is_out = (c & MFP_DIR_OUT) ? 1 : 0;
62 
63 	if (fn > 3)
64 		return -EINVAL;
65 
66 	/* alternate function and direction at run-time */
67 	gafr = (uorl == 0) ? GAFR_L(bank) : GAFR_U(bank);
68 	gafr = (gafr & ~(0x3 << shft)) | (fn << shft);
69 
70 	if (uorl == 0)
71 		GAFR_L(bank) = gafr;
72 	else
73 		GAFR_U(bank) = gafr;
74 
75 	if (is_out ^ gpio_desc[gpio].dir_inverted)
76 		GPDR(gpio) |= mask;
77 	else
78 		GPDR(gpio) &= ~mask;
79 
80 	/* alternate function and direction at low power mode */
81 	switch (c & MFP_LPM_STATE_MASK) {
82 	case MFP_LPM_DRIVE_HIGH:
83 		PGSR(bank) |= mask;
84 		is_out = 1;
85 		break;
86 	case MFP_LPM_DRIVE_LOW:
87 		PGSR(bank) &= ~mask;
88 		is_out = 1;
89 		break;
90 	case MFP_LPM_INPUT:
91 	case MFP_LPM_DEFAULT:
92 		break;
93 	default:
94 		/* warning and fall through, treat as MFP_LPM_DEFAULT */
95 		pr_warn("%s: GPIO%d: unsupported low power mode\n",
96 			__func__, gpio);
97 		break;
98 	}
99 
100 	if (is_out ^ gpio_desc[gpio].dir_inverted)
101 		gpdr_lpm[bank] |= mask;
102 	else
103 		gpdr_lpm[bank] &= ~mask;
104 
105 	/* give early warning if MFP_LPM_CAN_WAKEUP is set on the
106 	 * configurations of those pins not able to wakeup
107 	 */
108 	if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
109 		pr_warn("%s: GPIO%d unable to wakeup\n", __func__, gpio);
110 		return -EINVAL;
111 	}
112 
113 	if ((c & MFP_LPM_CAN_WAKEUP) && is_out) {
114 		pr_warn("%s: output GPIO%d unable to wakeup\n", __func__, gpio);
115 		return -EINVAL;
116 	}
117 
118 	return 0;
119 }
120 
__mfp_validate(int mfp)121 static inline int __mfp_validate(int mfp)
122 {
123 	int gpio = mfp_to_gpio(mfp);
124 
125 	if ((mfp > MFP_PIN_GPIO127) || !gpio_desc[gpio].valid) {
126 		pr_warn("%s: GPIO%d is invalid pin\n", __func__, gpio);
127 		return -1;
128 	}
129 
130 	return gpio;
131 }
132 
pxa2xx_mfp_config(unsigned long * mfp_cfgs,int num)133 void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
134 {
135 	unsigned long flags;
136 	unsigned long *c;
137 	int i, gpio;
138 
139 	for (i = 0, c = mfp_cfgs; i < num; i++, c++) {
140 
141 		gpio = __mfp_validate(MFP_PIN(*c));
142 		if (gpio < 0)
143 			continue;
144 
145 		local_irq_save(flags);
146 
147 		gpio_desc[gpio].config = *c;
148 		__mfp_config_gpio(gpio, *c);
149 
150 		local_irq_restore(flags);
151 	}
152 }
153 
pxa2xx_mfp_set_lpm(int mfp,unsigned long lpm)154 void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
155 {
156 	unsigned long flags, c;
157 	int gpio;
158 
159 	gpio = __mfp_validate(mfp);
160 	if (gpio < 0)
161 		return;
162 
163 	local_irq_save(flags);
164 
165 	c = gpio_desc[gpio].config;
166 	c = (c & ~MFP_LPM_STATE_MASK) | lpm;
167 	__mfp_config_gpio(gpio, c);
168 
169 	local_irq_restore(flags);
170 }
171 
gpio_set_wake(unsigned int gpio,unsigned int on)172 int gpio_set_wake(unsigned int gpio, unsigned int on)
173 {
174 	struct gpio_desc *d;
175 	unsigned long c, mux_taken;
176 
177 	if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
178 		return -EINVAL;
179 
180 	d = &gpio_desc[gpio];
181 	c = d->config;
182 
183 	if (!d->valid)
184 		return -EINVAL;
185 
186 	/* Allow keypad GPIOs to wakeup system when
187 	 * configured as generic GPIOs.
188 	 */
189 	if (d->keypad_gpio && (MFP_AF(d->config) == 0) &&
190 	    (d->config & MFP_LPM_CAN_WAKEUP)) {
191 		if (on)
192 			PKWR |= d->mask;
193 		else
194 			PKWR &= ~d->mask;
195 		return 0;
196 	}
197 
198 	mux_taken = (PWER & d->mux_mask) & (~d->mask);
199 	if (on && mux_taken)
200 		return -EBUSY;
201 
202 	if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
203 		if (on) {
204 			PWER = (PWER & ~d->mux_mask) | d->mask;
205 
206 			if (c & MFP_LPM_EDGE_RISE)
207 				PRER |= d->mask;
208 			else
209 				PRER &= ~d->mask;
210 
211 			if (c & MFP_LPM_EDGE_FALL)
212 				PFER |= d->mask;
213 			else
214 				PFER &= ~d->mask;
215 		} else {
216 			PWER &= ~d->mask;
217 			PRER &= ~d->mask;
218 			PFER &= ~d->mask;
219 		}
220 	}
221 	return 0;
222 }
223 
224 #ifdef CONFIG_PXA25x
pxa25x_mfp_init(void)225 static void __init pxa25x_mfp_init(void)
226 {
227 	int i;
228 
229 	/* running before pxa_gpio_probe() */
230 	pxa_last_gpio = 84;
231 	for (i = 0; i <= pxa_last_gpio; i++)
232 		gpio_desc[i].valid = 1;
233 
234 	for (i = 0; i <= 15; i++) {
235 		gpio_desc[i].can_wakeup = 1;
236 		gpio_desc[i].mask = GPIO_bit(i);
237 	}
238 
239 	/* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
240 	 * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
241 	 */
242 	for (i = 86; i <= pxa_last_gpio; i++)
243 		gpio_desc[i].dir_inverted = 1;
244 }
245 #else
pxa25x_mfp_init(void)246 static inline void pxa25x_mfp_init(void) {}
247 #endif /* CONFIG_PXA25x */
248 
249 #ifdef CONFIG_PXA27x
250 static int pxa27x_pkwr_gpio[] = {
251 	13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
252 	95, 96, 97, 98, 99, 100, 101, 102
253 };
254 
keypad_set_wake(unsigned int on)255 int keypad_set_wake(unsigned int on)
256 {
257 	unsigned int i, gpio, mask = 0;
258 	struct gpio_desc *d;
259 
260 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
261 
262 		gpio = pxa27x_pkwr_gpio[i];
263 		d = &gpio_desc[gpio];
264 
265 		/* skip if configured as generic GPIO */
266 		if (MFP_AF(d->config) == 0)
267 			continue;
268 
269 		if (d->config & MFP_LPM_CAN_WAKEUP)
270 			mask |= gpio_desc[gpio].mask;
271 	}
272 
273 	if (on)
274 		PKWR |= mask;
275 	else
276 		PKWR &= ~mask;
277 	return 0;
278 }
279 
280 #define PWER_WEMUX2_GPIO38	(1 << 16)
281 #define PWER_WEMUX2_GPIO53	(2 << 16)
282 #define PWER_WEMUX2_GPIO40	(3 << 16)
283 #define PWER_WEMUX2_GPIO36	(4 << 16)
284 #define PWER_WEMUX2_MASK	(7 << 16)
285 #define PWER_WEMUX3_GPIO31	(1 << 19)
286 #define PWER_WEMUX3_GPIO113	(2 << 19)
287 #define PWER_WEMUX3_MASK	(3 << 19)
288 
289 #define INIT_GPIO_DESC_MUXED(mux, gpio)				\
290 do {								\
291 	gpio_desc[(gpio)].can_wakeup = 1;			\
292 	gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;	\
293 	gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;	\
294 } while (0)
295 
pxa27x_mfp_init(void)296 static void __init pxa27x_mfp_init(void)
297 {
298 	int i, gpio;
299 
300 	pxa_last_gpio = 120;	/* running before pxa_gpio_probe() */
301 	for (i = 0; i <= pxa_last_gpio; i++) {
302 		/* skip GPIO2, 5, 6, 7, 8, they are not
303 		 * valid pins allow configuration
304 		 */
305 		if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
306 			continue;
307 
308 		gpio_desc[i].valid = 1;
309 	}
310 
311 	/* Keypad GPIOs */
312 	for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
313 		gpio = pxa27x_pkwr_gpio[i];
314 		gpio_desc[gpio].can_wakeup = 1;
315 		gpio_desc[gpio].keypad_gpio = 1;
316 		gpio_desc[gpio].mask = 1 << i;
317 	}
318 
319 	/* Overwrite GPIO13 as a PWER wakeup source */
320 	for (i = 0; i <= 15; i++) {
321 		/* skip GPIO2, 5, 6, 7, 8 */
322 		if (GPIO_bit(i) & 0x1e4)
323 			continue;
324 
325 		gpio_desc[i].can_wakeup = 1;
326 		gpio_desc[i].mask = GPIO_bit(i);
327 	}
328 
329 	gpio_desc[35].can_wakeup = 1;
330 	gpio_desc[35].mask = PWER_WE35;
331 
332 	INIT_GPIO_DESC_MUXED(WEMUX3, 31);
333 	INIT_GPIO_DESC_MUXED(WEMUX3, 113);
334 	INIT_GPIO_DESC_MUXED(WEMUX2, 38);
335 	INIT_GPIO_DESC_MUXED(WEMUX2, 53);
336 	INIT_GPIO_DESC_MUXED(WEMUX2, 40);
337 	INIT_GPIO_DESC_MUXED(WEMUX2, 36);
338 }
339 #else
pxa27x_mfp_init(void)340 static inline void pxa27x_mfp_init(void) {}
341 #endif /* CONFIG_PXA27x */
342 
343 #ifdef CONFIG_PM
344 static unsigned long saved_gafr[2][4];
345 static unsigned long saved_gpdr[4];
346 static unsigned long saved_gplr[4];
347 static unsigned long saved_pgsr[4];
348 
pxa2xx_mfp_suspend(void)349 static int pxa2xx_mfp_suspend(void)
350 {
351 	int i;
352 
353 	/* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
354 	for (i = 0; i < pxa_last_gpio; i++) {
355 		if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
356 		    (GPDR(i) & GPIO_bit(i))) {
357 			if (GPLR(i) & GPIO_bit(i))
358 				PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
359 			else
360 				PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
361 		}
362 	}
363 
364 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
365 		saved_gafr[0][i] = GAFR_L(i);
366 		saved_gafr[1][i] = GAFR_U(i);
367 		saved_gpdr[i] = GPDR(i * 32);
368 		saved_gplr[i] = GPLR(i * 32);
369 		saved_pgsr[i] = PGSR(i);
370 
371 		GPSR(i * 32) = PGSR(i);
372 		GPCR(i * 32) = ~PGSR(i);
373 	}
374 
375 	/* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
376 	for (i = 0; i < pxa_last_gpio; i++) {
377 		if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
378 		    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
379 		     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
380 			GPDR(i) |= GPIO_bit(i);
381 		else
382 			GPDR(i) &= ~GPIO_bit(i);
383 	}
384 
385 	return 0;
386 }
387 
pxa2xx_mfp_resume(void)388 static void pxa2xx_mfp_resume(void)
389 {
390 	int i;
391 
392 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
393 		GAFR_L(i) = saved_gafr[0][i];
394 		GAFR_U(i) = saved_gafr[1][i];
395 		GPSR(i * 32) = saved_gplr[i];
396 		GPCR(i * 32) = ~saved_gplr[i];
397 		GPDR(i * 32) = saved_gpdr[i];
398 		PGSR(i) = saved_pgsr[i];
399 	}
400 	PSSR = PSSR_RDH | PSSR_PH;
401 }
402 #else
403 #define pxa2xx_mfp_suspend	NULL
404 #define pxa2xx_mfp_resume	NULL
405 #endif
406 
407 struct syscore_ops pxa2xx_mfp_syscore_ops = {
408 	.suspend	= pxa2xx_mfp_suspend,
409 	.resume		= pxa2xx_mfp_resume,
410 };
411 
pxa2xx_mfp_init(void)412 static int __init pxa2xx_mfp_init(void)
413 {
414 	int i;
415 
416 	if (!cpu_is_pxa2xx())
417 		return 0;
418 
419 	if (cpu_is_pxa25x())
420 		pxa25x_mfp_init();
421 
422 	if (cpu_is_pxa27x())
423 		pxa27x_mfp_init();
424 
425 	/* clear RDH bit to enable GPIO receivers after reset/sleep exit */
426 	PSSR = PSSR_RDH;
427 
428 	/* initialize gafr_run[], pgsr_lpm[] from existing values */
429 	for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
430 		gpdr_lpm[i] = GPDR(i * 32);
431 
432 	return 0;
433 }
434 postcore_initcall(pxa2xx_mfp_init);
435