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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) ST-Ericsson SA 2010
  4 *
  5 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
  6 */
  7
  8#include <linux/cleanup.h>
  9#include <linux/init.h>
 10#include <linux/platform_device.h>
 11#include <linux/slab.h>
 12#include <linux/gpio/driver.h>
 13#include <linux/interrupt.h>
 14#include <linux/of.h>
 15#include <linux/mfd/stmpe.h>
 16#include <linux/seq_file.h>
 17#include <linux/bitops.h>
 18
 19/*
 20 * These registers are modified under the irq bus lock and cached to avoid
 21 * unnecessary writes in bus_sync_unlock.
 22 */
 23enum { REG_RE, REG_FE, REG_IE };
 24
 25enum { LSB, CSB, MSB };
 26
 27#define CACHE_NR_REGS	3
 28/* No variant has more than 24 GPIOs */
 29#define CACHE_NR_BANKS	(24 / 8)
 30
 31struct stmpe_gpio {
 32	struct gpio_chip chip;
 33	struct stmpe *stmpe;
 34	struct device *dev;
 35	struct mutex irq_lock;
 36	u32 norequest_mask;
 37	/* Caches of interrupt control registers for bus_lock */
 38	u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS];
 39	u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS];
 40};
 41
 42static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset)
 43{
 44	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 45	struct stmpe *stmpe = stmpe_gpio->stmpe;
 46	u8 reg = stmpe->regs[STMPE_IDX_GPMR_LSB + (offset / 8)];
 47	u8 mask = BIT(offset % 8);
 48	int ret;
 49
 50	ret = stmpe_reg_read(stmpe, reg);
 51	if (ret < 0)
 52		return ret;
 53
 54	return !!(ret & mask);
 55}
 56
 57static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
 58{
 59	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 60	struct stmpe *stmpe = stmpe_gpio->stmpe;
 61	int which = val ? STMPE_IDX_GPSR_LSB : STMPE_IDX_GPCR_LSB;
 62	u8 reg = stmpe->regs[which + (offset / 8)];
 63	u8 mask = BIT(offset % 8);
 64
 65	/*
 66	 * Some variants have single register for gpio set/clear functionality.
 67	 * For them we need to write 0 to clear and 1 to set.
 68	 */
 69	if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB])
 70		stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
 71	else
 72		stmpe_reg_write(stmpe, reg, mask);
 73}
 74
 75static int stmpe_gpio_get_direction(struct gpio_chip *chip,
 76				    unsigned offset)
 77{
 78	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 79	struct stmpe *stmpe = stmpe_gpio->stmpe;
 80	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
 81	u8 mask = BIT(offset % 8);
 82	int ret;
 83
 84	ret = stmpe_reg_read(stmpe, reg);
 85	if (ret < 0)
 86		return ret;
 87
 88	if (ret & mask)
 89		return GPIO_LINE_DIRECTION_OUT;
 90
 91	return GPIO_LINE_DIRECTION_IN;
 92}
 93
 94static int stmpe_gpio_direction_output(struct gpio_chip *chip,
 95					 unsigned offset, int val)
 96{
 97	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 98	struct stmpe *stmpe = stmpe_gpio->stmpe;
 99	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
100	u8 mask = BIT(offset % 8);
101
102	stmpe_gpio_set(chip, offset, val);
103
104	return stmpe_set_bits(stmpe, reg, mask, mask);
105}
106
107static int stmpe_gpio_direction_input(struct gpio_chip *chip,
108					unsigned offset)
109{
110	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
111	struct stmpe *stmpe = stmpe_gpio->stmpe;
112	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
113	u8 mask = BIT(offset % 8);
114
115	return stmpe_set_bits(stmpe, reg, mask, 0);
116}
117
118static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset)
119{
120	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
121	struct stmpe *stmpe = stmpe_gpio->stmpe;
122
123	if (stmpe_gpio->norequest_mask & BIT(offset))
124		return -EINVAL;
125
126	return stmpe_set_altfunc(stmpe, BIT(offset), STMPE_BLOCK_GPIO);
127}
128
129static const struct gpio_chip template_chip = {
130	.label			= "stmpe",
131	.owner			= THIS_MODULE,
132	.get_direction		= stmpe_gpio_get_direction,
133	.direction_input	= stmpe_gpio_direction_input,
134	.get			= stmpe_gpio_get,
135	.direction_output	= stmpe_gpio_direction_output,
136	.set			= stmpe_gpio_set,
137	.request		= stmpe_gpio_request,
138	.can_sleep		= true,
139};
140
141static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
142{
143	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
144	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
145	int offset = d->hwirq;
146	int regoffset = offset / 8;
147	int mask = BIT(offset % 8);
148
149	if (type & IRQ_TYPE_LEVEL_LOW || type & IRQ_TYPE_LEVEL_HIGH)
150		return -EINVAL;
151
152	/* STMPE801 and STMPE 1600 don't have RE and FE registers */
153	if (stmpe_gpio->stmpe->partnum == STMPE801 ||
154	    stmpe_gpio->stmpe->partnum == STMPE1600)
155		return 0;
156
157	if (type & IRQ_TYPE_EDGE_RISING)
158		stmpe_gpio->regs[REG_RE][regoffset] |= mask;
159	else
160		stmpe_gpio->regs[REG_RE][regoffset] &= ~mask;
161
162	if (type & IRQ_TYPE_EDGE_FALLING)
163		stmpe_gpio->regs[REG_FE][regoffset] |= mask;
164	else
165		stmpe_gpio->regs[REG_FE][regoffset] &= ~mask;
166
167	return 0;
168}
169
170static void stmpe_gpio_irq_lock(struct irq_data *d)
171{
172	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
173	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
174
175	mutex_lock(&stmpe_gpio->irq_lock);
176}
177
178static void stmpe_gpio_irq_sync_unlock(struct irq_data *d)
179{
180	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
181	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
182	struct stmpe *stmpe = stmpe_gpio->stmpe;
183	int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
184	static const u8 regmap[CACHE_NR_REGS][CACHE_NR_BANKS] = {
185		[REG_RE][LSB] = STMPE_IDX_GPRER_LSB,
186		[REG_RE][CSB] = STMPE_IDX_GPRER_CSB,
187		[REG_RE][MSB] = STMPE_IDX_GPRER_MSB,
188		[REG_FE][LSB] = STMPE_IDX_GPFER_LSB,
189		[REG_FE][CSB] = STMPE_IDX_GPFER_CSB,
190		[REG_FE][MSB] = STMPE_IDX_GPFER_MSB,
191		[REG_IE][LSB] = STMPE_IDX_IEGPIOR_LSB,
192		[REG_IE][CSB] = STMPE_IDX_IEGPIOR_CSB,
193		[REG_IE][MSB] = STMPE_IDX_IEGPIOR_MSB,
194	};
195	int i, j;
196
197	/*
198	 * STMPE1600: to be able to get IRQ from pins,
199	 * a read must be done on GPMR register, or a write in
200	 * GPSR or GPCR registers
201	 */
202	if (stmpe->partnum == STMPE1600) {
203		stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_LSB]);
204		stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_CSB]);
205	}
206
207	for (i = 0; i < CACHE_NR_REGS; i++) {
208		/* STMPE801 and STMPE1600 don't have RE and FE registers */
209		if ((stmpe->partnum == STMPE801 ||
210		     stmpe->partnum == STMPE1600) &&
211		     (i != REG_IE))
212			continue;
213
214		for (j = 0; j < num_banks; j++) {
215			u8 old = stmpe_gpio->oldregs[i][j];
216			u8 new = stmpe_gpio->regs[i][j];
217
218			if (new == old)
219				continue;
220
221			stmpe_gpio->oldregs[i][j] = new;
222			stmpe_reg_write(stmpe, stmpe->regs[regmap[i][j]], new);
223		}
224	}
225
226	mutex_unlock(&stmpe_gpio->irq_lock);
227}
228
229static void stmpe_gpio_irq_mask(struct irq_data *d)
230{
231	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
232	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
233	int offset = d->hwirq;
234	int regoffset = offset / 8;
235	int mask = BIT(offset % 8);
236
237	stmpe_gpio->regs[REG_IE][regoffset] &= ~mask;
238	gpiochip_disable_irq(gc, offset);
239}
240
241static void stmpe_gpio_irq_unmask(struct irq_data *d)
242{
243	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
244	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
245	int offset = d->hwirq;
246	int regoffset = offset / 8;
247	int mask = BIT(offset % 8);
248
249	gpiochip_enable_irq(gc, offset);
250	stmpe_gpio->regs[REG_IE][regoffset] |= mask;
251}
252
253static void stmpe_dbg_show_one(struct seq_file *s,
254			       struct gpio_chip *gc,
255			       unsigned offset, unsigned gpio)
256{
257	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
258	struct stmpe *stmpe = stmpe_gpio->stmpe;
 
259	bool val = !!stmpe_gpio_get(gc, offset);
260	u8 bank = offset / 8;
261	u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB + bank];
262	u8 mask = BIT(offset % 8);
263	int ret;
264	u8 dir;
265
266	char *label __free(kfree) = gpiochip_dup_line_label(gc, offset);
267	if (IS_ERR(label))
268		return;
269
270	ret = stmpe_reg_read(stmpe, dir_reg);
271	if (ret < 0)
272		return;
273	dir = !!(ret & mask);
274
275	if (dir) {
276		seq_printf(s, " gpio-%-3d (%-20.20s) out %s",
277			   gpio, label ?: "(none)",
278			   val ? "hi" : "lo");
279	} else {
280		u8 edge_det_reg;
281		u8 rise_reg;
282		u8 fall_reg;
283		u8 irqen_reg;
284
285		static const char * const edge_det_values[] = {
286			"edge-inactive",
287			"edge-asserted",
288			"not-supported"
289		};
290		static const char * const rise_values[] = {
291			"no-rising-edge-detection",
292			"rising-edge-detection",
293			"not-supported"
294		};
295		static const char * const fall_values[] = {
296			"no-falling-edge-detection",
297			"falling-edge-detection",
298			"not-supported"
299		};
300		#define NOT_SUPPORTED_IDX 2
301		u8 edge_det = NOT_SUPPORTED_IDX;
302		u8 rise = NOT_SUPPORTED_IDX;
303		u8 fall = NOT_SUPPORTED_IDX;
304		bool irqen;
305
306		switch (stmpe->partnum) {
307		case STMPE610:
308		case STMPE811:
309		case STMPE1601:
310		case STMPE2401:
311		case STMPE2403:
312			edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_LSB + bank];
313			ret = stmpe_reg_read(stmpe, edge_det_reg);
314			if (ret < 0)
315				return;
316			edge_det = !!(ret & mask);
317			fallthrough;
318		case STMPE1801:
319			rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB + bank];
320			fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB + bank];
321
322			ret = stmpe_reg_read(stmpe, rise_reg);
323			if (ret < 0)
324				return;
325			rise = !!(ret & mask);
326			ret = stmpe_reg_read(stmpe, fall_reg);
327			if (ret < 0)
328				return;
329			fall = !!(ret & mask);
330			fallthrough;
331		case STMPE801:
332		case STMPE1600:
333			irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB + bank];
334			break;
335
336		default:
337			return;
338		}
339
340		ret = stmpe_reg_read(stmpe, irqen_reg);
341		if (ret < 0)
342			return;
343		irqen = !!(ret & mask);
344
345		seq_printf(s, " gpio-%-3d (%-20.20s) in  %s %13s %13s %25s %25s",
346			   gpio, label ?: "(none)",
347			   val ? "hi" : "lo",
348			   edge_det_values[edge_det],
349			   irqen ? "IRQ-enabled" : "IRQ-disabled",
350			   rise_values[rise],
351			   fall_values[fall]);
352	}
353}
354
355static void stmpe_dbg_show(struct seq_file *s, struct gpio_chip *gc)
356{
357	unsigned i;
358	unsigned gpio = gc->base;
359
360	for (i = 0; i < gc->ngpio; i++, gpio++) {
361		stmpe_dbg_show_one(s, gc, i, gpio);
362		seq_putc(s, '\n');
363	}
364}
365
366static const struct irq_chip stmpe_gpio_irq_chip = {
367	.name			= "stmpe-gpio",
368	.irq_bus_lock		= stmpe_gpio_irq_lock,
369	.irq_bus_sync_unlock	= stmpe_gpio_irq_sync_unlock,
370	.irq_mask		= stmpe_gpio_irq_mask,
371	.irq_unmask		= stmpe_gpio_irq_unmask,
372	.irq_set_type		= stmpe_gpio_irq_set_type,
373	.flags			= IRQCHIP_IMMUTABLE,
374	GPIOCHIP_IRQ_RESOURCE_HELPERS,
375};
376
377#define MAX_GPIOS 24
378
379static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
380{
381	struct stmpe_gpio *stmpe_gpio = dev;
382	struct stmpe *stmpe = stmpe_gpio->stmpe;
383	u8 statmsbreg;
384	int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
385	u8 status[DIV_ROUND_UP(MAX_GPIOS, 8)];
386	int ret;
387	int i;
388
389	/*
390	 * the stmpe_block_read() call below, imposes to set statmsbreg
391	 * with the register located at the lowest address. As STMPE1600
392	 * variant is the only one which respect registers address's order
393	 * (LSB regs located at lowest address than MSB ones) whereas all
394	 * the others have a registers layout with MSB located before the
395	 * LSB regs.
396	 */
397	if (stmpe->partnum == STMPE1600)
398		statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_LSB];
399	else
400		statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB];
401
402	ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status);
403	if (ret < 0)
404		return IRQ_NONE;
405
406	for (i = 0; i < num_banks; i++) {
407		int bank = (stmpe_gpio->stmpe->partnum == STMPE1600) ? i :
408			   num_banks - i - 1;
409		unsigned int enabled = stmpe_gpio->regs[REG_IE][bank];
410		unsigned int stat = status[i];
411
412		stat &= enabled;
413		if (!stat)
414			continue;
415
416		while (stat) {
417			int bit = __ffs(stat);
418			int line = bank * 8 + bit;
419			int child_irq = irq_find_mapping(stmpe_gpio->chip.irq.domain,
420							 line);
421
422			handle_nested_irq(child_irq);
423			stat &= ~BIT(bit);
424		}
425
426		/*
427		 * interrupt status register write has no effect on
428		 * 801/1801/1600, bits are cleared when read.
429		 * Edge detect register is not present on 801/1600/1801
430		 */
431		if (stmpe->partnum != STMPE801 && stmpe->partnum != STMPE1600 &&
432		    stmpe->partnum != STMPE1801) {
433			stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
434			stmpe_reg_write(stmpe,
435					stmpe->regs[STMPE_IDX_GPEDR_MSB] + i,
436					status[i]);
437		}
438	}
439
440	return IRQ_HANDLED;
441}
442
443static void stmpe_init_irq_valid_mask(struct gpio_chip *gc,
444				      unsigned long *valid_mask,
445				      unsigned int ngpios)
446{
447	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
448	int i;
449
450	if (!stmpe_gpio->norequest_mask)
451		return;
452
453	/* Forbid unused lines to be mapped as IRQs */
454	for (i = 0; i < sizeof(u32); i++) {
455		if (stmpe_gpio->norequest_mask & BIT(i))
456			clear_bit(i, valid_mask);
457	}
458}
459
460static void stmpe_gpio_disable(void *stmpe)
461{
462	stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
463}
464
465static int stmpe_gpio_probe(struct platform_device *pdev)
466{
467	struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
468	struct device_node *np = pdev->dev.of_node;
469	struct stmpe_gpio *stmpe_gpio;
470	int ret, irq;
471
472	if (stmpe->num_gpios > MAX_GPIOS) {
473		dev_err(&pdev->dev, "Need to increase maximum GPIO number\n");
474		return -EINVAL;
475	}
476
477	stmpe_gpio = devm_kzalloc(&pdev->dev, sizeof(*stmpe_gpio), GFP_KERNEL);
478	if (!stmpe_gpio)
479		return -ENOMEM;
480
481	mutex_init(&stmpe_gpio->irq_lock);
482
483	stmpe_gpio->dev = &pdev->dev;
484	stmpe_gpio->stmpe = stmpe;
485	stmpe_gpio->chip = template_chip;
486	stmpe_gpio->chip.ngpio = stmpe->num_gpios;
487	stmpe_gpio->chip.parent = &pdev->dev;
 
488	stmpe_gpio->chip.base = -1;
 
 
 
 
 
 
 
 
 
489
490	if (IS_ENABLED(CONFIG_DEBUG_FS))
491                stmpe_gpio->chip.dbg_show = stmpe_dbg_show;
492
493	of_property_read_u32(np, "st,norequest-mask",
494			&stmpe_gpio->norequest_mask);
495
496	irq = platform_get_irq(pdev, 0);
497	if (irq < 0)
498		dev_info(&pdev->dev,
499			"device configured in no-irq mode: "
500			"irqs are not available\n");
501
502	ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
503	if (ret)
504		return ret;
505
506	ret = devm_add_action_or_reset(&pdev->dev, stmpe_gpio_disable, stmpe);
507	if (ret)
508		return ret;
 
 
509
510	if (irq > 0) {
511		struct gpio_irq_chip *girq;
512
513		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
514				stmpe_gpio_irq, IRQF_ONESHOT,
515				"stmpe-gpio", stmpe_gpio);
516		if (ret) {
517			dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
518			return ret;
 
 
 
 
 
 
 
 
 
 
519		}
520
521		girq = &stmpe_gpio->chip.irq;
522		gpio_irq_chip_set_chip(girq, &stmpe_gpio_irq_chip);
523		/* This will let us handle the parent IRQ in the driver */
524		girq->parent_handler = NULL;
525		girq->num_parents = 0;
526		girq->parents = NULL;
527		girq->default_type = IRQ_TYPE_NONE;
528		girq->handler = handle_simple_irq;
529		girq->threaded = true;
530		girq->init_valid_mask = stmpe_init_irq_valid_mask;
531	}
532
533	return devm_gpiochip_add_data(&pdev->dev, &stmpe_gpio->chip, stmpe_gpio);
 
 
 
 
 
 
 
 
 
534}
535
536static struct platform_driver stmpe_gpio_driver = {
537	.driver = {
538		.suppress_bind_attrs	= true,
539		.name			= "stmpe-gpio",
540	},
541	.probe		= stmpe_gpio_probe,
542};
543
544static int __init stmpe_gpio_init(void)
545{
546	return platform_driver_register(&stmpe_gpio_driver);
547}
548subsys_initcall(stmpe_gpio_init);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) ST-Ericsson SA 2010
  4 *
  5 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
  6 */
  7
 
  8#include <linux/init.h>
  9#include <linux/platform_device.h>
 10#include <linux/slab.h>
 11#include <linux/gpio/driver.h>
 12#include <linux/interrupt.h>
 13#include <linux/of.h>
 14#include <linux/mfd/stmpe.h>
 15#include <linux/seq_file.h>
 16#include <linux/bitops.h>
 17
 18/*
 19 * These registers are modified under the irq bus lock and cached to avoid
 20 * unnecessary writes in bus_sync_unlock.
 21 */
 22enum { REG_RE, REG_FE, REG_IE };
 23
 24enum { LSB, CSB, MSB };
 25
 26#define CACHE_NR_REGS	3
 27/* No variant has more than 24 GPIOs */
 28#define CACHE_NR_BANKS	(24 / 8)
 29
 30struct stmpe_gpio {
 31	struct gpio_chip chip;
 32	struct stmpe *stmpe;
 33	struct device *dev;
 34	struct mutex irq_lock;
 35	u32 norequest_mask;
 36	/* Caches of interrupt control registers for bus_lock */
 37	u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS];
 38	u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS];
 39};
 40
 41static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset)
 42{
 43	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 44	struct stmpe *stmpe = stmpe_gpio->stmpe;
 45	u8 reg = stmpe->regs[STMPE_IDX_GPMR_LSB + (offset / 8)];
 46	u8 mask = BIT(offset % 8);
 47	int ret;
 48
 49	ret = stmpe_reg_read(stmpe, reg);
 50	if (ret < 0)
 51		return ret;
 52
 53	return !!(ret & mask);
 54}
 55
 56static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
 57{
 58	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 59	struct stmpe *stmpe = stmpe_gpio->stmpe;
 60	int which = val ? STMPE_IDX_GPSR_LSB : STMPE_IDX_GPCR_LSB;
 61	u8 reg = stmpe->regs[which + (offset / 8)];
 62	u8 mask = BIT(offset % 8);
 63
 64	/*
 65	 * Some variants have single register for gpio set/clear functionality.
 66	 * For them we need to write 0 to clear and 1 to set.
 67	 */
 68	if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB])
 69		stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
 70	else
 71		stmpe_reg_write(stmpe, reg, mask);
 72}
 73
 74static int stmpe_gpio_get_direction(struct gpio_chip *chip,
 75				    unsigned offset)
 76{
 77	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 78	struct stmpe *stmpe = stmpe_gpio->stmpe;
 79	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
 80	u8 mask = BIT(offset % 8);
 81	int ret;
 82
 83	ret = stmpe_reg_read(stmpe, reg);
 84	if (ret < 0)
 85		return ret;
 86
 87	return !(ret & mask);
 
 
 
 88}
 89
 90static int stmpe_gpio_direction_output(struct gpio_chip *chip,
 91					 unsigned offset, int val)
 92{
 93	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
 94	struct stmpe *stmpe = stmpe_gpio->stmpe;
 95	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
 96	u8 mask = BIT(offset % 8);
 97
 98	stmpe_gpio_set(chip, offset, val);
 99
100	return stmpe_set_bits(stmpe, reg, mask, mask);
101}
102
103static int stmpe_gpio_direction_input(struct gpio_chip *chip,
104					unsigned offset)
105{
106	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
107	struct stmpe *stmpe = stmpe_gpio->stmpe;
108	u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
109	u8 mask = BIT(offset % 8);
110
111	return stmpe_set_bits(stmpe, reg, mask, 0);
112}
113
114static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset)
115{
116	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
117	struct stmpe *stmpe = stmpe_gpio->stmpe;
118
119	if (stmpe_gpio->norequest_mask & BIT(offset))
120		return -EINVAL;
121
122	return stmpe_set_altfunc(stmpe, BIT(offset), STMPE_BLOCK_GPIO);
123}
124
125static const struct gpio_chip template_chip = {
126	.label			= "stmpe",
127	.owner			= THIS_MODULE,
128	.get_direction		= stmpe_gpio_get_direction,
129	.direction_input	= stmpe_gpio_direction_input,
130	.get			= stmpe_gpio_get,
131	.direction_output	= stmpe_gpio_direction_output,
132	.set			= stmpe_gpio_set,
133	.request		= stmpe_gpio_request,
134	.can_sleep		= true,
135};
136
137static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
138{
139	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
140	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
141	int offset = d->hwirq;
142	int regoffset = offset / 8;
143	int mask = BIT(offset % 8);
144
145	if (type & IRQ_TYPE_LEVEL_LOW || type & IRQ_TYPE_LEVEL_HIGH)
146		return -EINVAL;
147
148	/* STMPE801 and STMPE 1600 don't have RE and FE registers */
149	if (stmpe_gpio->stmpe->partnum == STMPE801 ||
150	    stmpe_gpio->stmpe->partnum == STMPE1600)
151		return 0;
152
153	if (type & IRQ_TYPE_EDGE_RISING)
154		stmpe_gpio->regs[REG_RE][regoffset] |= mask;
155	else
156		stmpe_gpio->regs[REG_RE][regoffset] &= ~mask;
157
158	if (type & IRQ_TYPE_EDGE_FALLING)
159		stmpe_gpio->regs[REG_FE][regoffset] |= mask;
160	else
161		stmpe_gpio->regs[REG_FE][regoffset] &= ~mask;
162
163	return 0;
164}
165
166static void stmpe_gpio_irq_lock(struct irq_data *d)
167{
168	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
169	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
170
171	mutex_lock(&stmpe_gpio->irq_lock);
172}
173
174static void stmpe_gpio_irq_sync_unlock(struct irq_data *d)
175{
176	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
177	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
178	struct stmpe *stmpe = stmpe_gpio->stmpe;
179	int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
180	static const u8 regmap[CACHE_NR_REGS][CACHE_NR_BANKS] = {
181		[REG_RE][LSB] = STMPE_IDX_GPRER_LSB,
182		[REG_RE][CSB] = STMPE_IDX_GPRER_CSB,
183		[REG_RE][MSB] = STMPE_IDX_GPRER_MSB,
184		[REG_FE][LSB] = STMPE_IDX_GPFER_LSB,
185		[REG_FE][CSB] = STMPE_IDX_GPFER_CSB,
186		[REG_FE][MSB] = STMPE_IDX_GPFER_MSB,
187		[REG_IE][LSB] = STMPE_IDX_IEGPIOR_LSB,
188		[REG_IE][CSB] = STMPE_IDX_IEGPIOR_CSB,
189		[REG_IE][MSB] = STMPE_IDX_IEGPIOR_MSB,
190	};
191	int i, j;
192
193	/*
194	 * STMPE1600: to be able to get IRQ from pins,
195	 * a read must be done on GPMR register, or a write in
196	 * GPSR or GPCR registers
197	 */
198	if (stmpe->partnum == STMPE1600) {
199		stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_LSB]);
200		stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_CSB]);
201	}
202
203	for (i = 0; i < CACHE_NR_REGS; i++) {
204		/* STMPE801 and STMPE1600 don't have RE and FE registers */
205		if ((stmpe->partnum == STMPE801 ||
206		     stmpe->partnum == STMPE1600) &&
207		     (i != REG_IE))
208			continue;
209
210		for (j = 0; j < num_banks; j++) {
211			u8 old = stmpe_gpio->oldregs[i][j];
212			u8 new = stmpe_gpio->regs[i][j];
213
214			if (new == old)
215				continue;
216
217			stmpe_gpio->oldregs[i][j] = new;
218			stmpe_reg_write(stmpe, stmpe->regs[regmap[i][j]], new);
219		}
220	}
221
222	mutex_unlock(&stmpe_gpio->irq_lock);
223}
224
225static void stmpe_gpio_irq_mask(struct irq_data *d)
226{
227	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
228	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
229	int offset = d->hwirq;
230	int regoffset = offset / 8;
231	int mask = BIT(offset % 8);
232
233	stmpe_gpio->regs[REG_IE][regoffset] &= ~mask;
 
234}
235
236static void stmpe_gpio_irq_unmask(struct irq_data *d)
237{
238	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
239	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
240	int offset = d->hwirq;
241	int regoffset = offset / 8;
242	int mask = BIT(offset % 8);
243
 
244	stmpe_gpio->regs[REG_IE][regoffset] |= mask;
245}
246
247static void stmpe_dbg_show_one(struct seq_file *s,
248			       struct gpio_chip *gc,
249			       unsigned offset, unsigned gpio)
250{
251	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
252	struct stmpe *stmpe = stmpe_gpio->stmpe;
253	const char *label = gpiochip_is_requested(gc, offset);
254	bool val = !!stmpe_gpio_get(gc, offset);
255	u8 bank = offset / 8;
256	u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB + bank];
257	u8 mask = BIT(offset % 8);
258	int ret;
259	u8 dir;
260
 
 
 
 
261	ret = stmpe_reg_read(stmpe, dir_reg);
262	if (ret < 0)
263		return;
264	dir = !!(ret & mask);
265
266	if (dir) {
267		seq_printf(s, " gpio-%-3d (%-20.20s) out %s",
268			   gpio, label ?: "(none)",
269			   val ? "hi" : "lo");
270	} else {
271		u8 edge_det_reg;
272		u8 rise_reg;
273		u8 fall_reg;
274		u8 irqen_reg;
275
276		static const char * const edge_det_values[] = {
277			"edge-inactive",
278			"edge-asserted",
279			"not-supported"
280		};
281		static const char * const rise_values[] = {
282			"no-rising-edge-detection",
283			"rising-edge-detection",
284			"not-supported"
285		};
286		static const char * const fall_values[] = {
287			"no-falling-edge-detection",
288			"falling-edge-detection",
289			"not-supported"
290		};
291		#define NOT_SUPPORTED_IDX 2
292		u8 edge_det = NOT_SUPPORTED_IDX;
293		u8 rise = NOT_SUPPORTED_IDX;
294		u8 fall = NOT_SUPPORTED_IDX;
295		bool irqen;
296
297		switch (stmpe->partnum) {
298		case STMPE610:
299		case STMPE811:
300		case STMPE1601:
301		case STMPE2401:
302		case STMPE2403:
303			edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_LSB + bank];
304			ret = stmpe_reg_read(stmpe, edge_det_reg);
305			if (ret < 0)
306				return;
307			edge_det = !!(ret & mask);
308			/* fall through */
309		case STMPE1801:
310			rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB + bank];
311			fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB + bank];
312
313			ret = stmpe_reg_read(stmpe, rise_reg);
314			if (ret < 0)
315				return;
316			rise = !!(ret & mask);
317			ret = stmpe_reg_read(stmpe, fall_reg);
318			if (ret < 0)
319				return;
320			fall = !!(ret & mask);
321			/* fall through */
322		case STMPE801:
323		case STMPE1600:
324			irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB + bank];
325			break;
326
327		default:
328			return;
329		}
330
331		ret = stmpe_reg_read(stmpe, irqen_reg);
332		if (ret < 0)
333			return;
334		irqen = !!(ret & mask);
335
336		seq_printf(s, " gpio-%-3d (%-20.20s) in  %s %13s %13s %25s %25s",
337			   gpio, label ?: "(none)",
338			   val ? "hi" : "lo",
339			   edge_det_values[edge_det],
340			   irqen ? "IRQ-enabled" : "IRQ-disabled",
341			   rise_values[rise],
342			   fall_values[fall]);
343	}
344}
345
346static void stmpe_dbg_show(struct seq_file *s, struct gpio_chip *gc)
347{
348	unsigned i;
349	unsigned gpio = gc->base;
350
351	for (i = 0; i < gc->ngpio; i++, gpio++) {
352		stmpe_dbg_show_one(s, gc, i, gpio);
353		seq_putc(s, '\n');
354	}
355}
356
357static struct irq_chip stmpe_gpio_irq_chip = {
358	.name			= "stmpe-gpio",
359	.irq_bus_lock		= stmpe_gpio_irq_lock,
360	.irq_bus_sync_unlock	= stmpe_gpio_irq_sync_unlock,
361	.irq_mask		= stmpe_gpio_irq_mask,
362	.irq_unmask		= stmpe_gpio_irq_unmask,
363	.irq_set_type		= stmpe_gpio_irq_set_type,
 
 
364};
365
366#define MAX_GPIOS 24
367
368static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
369{
370	struct stmpe_gpio *stmpe_gpio = dev;
371	struct stmpe *stmpe = stmpe_gpio->stmpe;
372	u8 statmsbreg;
373	int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
374	u8 status[DIV_ROUND_UP(MAX_GPIOS, 8)];
375	int ret;
376	int i;
377
378	/*
379	 * the stmpe_block_read() call below, imposes to set statmsbreg
380	 * with the register located at the lowest address. As STMPE1600
381	 * variant is the only one which respect registers address's order
382	 * (LSB regs located at lowest address than MSB ones) whereas all
383	 * the others have a registers layout with MSB located before the
384	 * LSB regs.
385	 */
386	if (stmpe->partnum == STMPE1600)
387		statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_LSB];
388	else
389		statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB];
390
391	ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status);
392	if (ret < 0)
393		return IRQ_NONE;
394
395	for (i = 0; i < num_banks; i++) {
396		int bank = (stmpe_gpio->stmpe->partnum == STMPE1600) ? i :
397			   num_banks - i - 1;
398		unsigned int enabled = stmpe_gpio->regs[REG_IE][bank];
399		unsigned int stat = status[i];
400
401		stat &= enabled;
402		if (!stat)
403			continue;
404
405		while (stat) {
406			int bit = __ffs(stat);
407			int line = bank * 8 + bit;
408			int child_irq = irq_find_mapping(stmpe_gpio->chip.irq.domain,
409							 line);
410
411			handle_nested_irq(child_irq);
412			stat &= ~BIT(bit);
413		}
414
415		/*
416		 * interrupt status register write has no effect on
417		 * 801/1801/1600, bits are cleared when read.
418		 * Edge detect register is not present on 801/1600/1801
419		 */
420		if (stmpe->partnum != STMPE801 && stmpe->partnum != STMPE1600 &&
421		    stmpe->partnum != STMPE1801) {
422			stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
423			stmpe_reg_write(stmpe,
424					stmpe->regs[STMPE_IDX_GPEDR_MSB] + i,
425					status[i]);
426		}
427	}
428
429	return IRQ_HANDLED;
430}
431
432static void stmpe_init_irq_valid_mask(struct gpio_chip *gc,
433				      unsigned long *valid_mask,
434				      unsigned int ngpios)
435{
436	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
437	int i;
438
439	if (!stmpe_gpio->norequest_mask)
440		return;
441
442	/* Forbid unused lines to be mapped as IRQs */
443	for (i = 0; i < sizeof(u32); i++) {
444		if (stmpe_gpio->norequest_mask & BIT(i))
445			clear_bit(i, valid_mask);
446	}
447}
448
 
 
 
 
 
449static int stmpe_gpio_probe(struct platform_device *pdev)
450{
451	struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
452	struct device_node *np = pdev->dev.of_node;
453	struct stmpe_gpio *stmpe_gpio;
454	int ret, irq;
455
456	if (stmpe->num_gpios > MAX_GPIOS) {
457		dev_err(&pdev->dev, "Need to increase maximum GPIO number\n");
458		return -EINVAL;
459	}
460
461	stmpe_gpio = kzalloc(sizeof(*stmpe_gpio), GFP_KERNEL);
462	if (!stmpe_gpio)
463		return -ENOMEM;
464
465	mutex_init(&stmpe_gpio->irq_lock);
466
467	stmpe_gpio->dev = &pdev->dev;
468	stmpe_gpio->stmpe = stmpe;
469	stmpe_gpio->chip = template_chip;
470	stmpe_gpio->chip.ngpio = stmpe->num_gpios;
471	stmpe_gpio->chip.parent = &pdev->dev;
472	stmpe_gpio->chip.of_node = np;
473	stmpe_gpio->chip.base = -1;
474	/*
475	 * REVISIT: this makes sure the valid mask gets allocated and
476	 * filled in when adding the gpio_chip, but the rest of the
477	 * gpio_irqchip is still filled in using the old method
478	 * in gpiochip_irqchip_add_nested() so clean this up once we
479	 * get the gpio_irqchip to initialize while adding the
480	 * gpio_chip also for threaded irqchips.
481	 */
482	stmpe_gpio->chip.irq.init_valid_mask = stmpe_init_irq_valid_mask;
483
484	if (IS_ENABLED(CONFIG_DEBUG_FS))
485                stmpe_gpio->chip.dbg_show = stmpe_dbg_show;
486
487	of_property_read_u32(np, "st,norequest-mask",
488			&stmpe_gpio->norequest_mask);
489
490	irq = platform_get_irq(pdev, 0);
491	if (irq < 0)
492		dev_info(&pdev->dev,
493			"device configured in no-irq mode: "
494			"irqs are not available\n");
495
496	ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
497	if (ret)
498		goto out_free;
499
500	ret = gpiochip_add_data(&stmpe_gpio->chip, stmpe_gpio);
501	if (ret) {
502		dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
503		goto out_disable;
504	}
505
506	if (irq > 0) {
 
 
507		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
508				stmpe_gpio_irq, IRQF_ONESHOT,
509				"stmpe-gpio", stmpe_gpio);
510		if (ret) {
511			dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
512			goto out_disable;
513		}
514		ret =  gpiochip_irqchip_add_nested(&stmpe_gpio->chip,
515						   &stmpe_gpio_irq_chip,
516						   0,
517						   handle_simple_irq,
518						   IRQ_TYPE_NONE);
519		if (ret) {
520			dev_err(&pdev->dev,
521				"could not connect irqchip to gpiochip\n");
522			goto out_disable;
523		}
524
525		gpiochip_set_nested_irqchip(&stmpe_gpio->chip,
526					    &stmpe_gpio_irq_chip,
527					    irq);
 
 
 
 
 
 
 
528	}
529
530	platform_set_drvdata(pdev, stmpe_gpio);
531
532	return 0;
533
534out_disable:
535	stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
536	gpiochip_remove(&stmpe_gpio->chip);
537out_free:
538	kfree(stmpe_gpio);
539	return ret;
540}
541
542static struct platform_driver stmpe_gpio_driver = {
543	.driver = {
544		.suppress_bind_attrs	= true,
545		.name			= "stmpe-gpio",
546	},
547	.probe		= stmpe_gpio_probe,
548};
549
550static int __init stmpe_gpio_init(void)
551{
552	return platform_driver_register(&stmpe_gpio_driver);
553}
554subsys_initcall(stmpe_gpio_init);