1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) ST-Ericsson SA 2010
5 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
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>
14 #include <linux/mfd/stmpe.h>
15 #include <linux/seq_file.h>
16 #include <linux/bitops.h>
19 * These registers are modified under the irq bus lock and cached to avoid
20 * unnecessary writes in bus_sync_unlock.
22 enum { REG_RE, REG_FE, REG_IE };
24 enum { LSB, CSB, MSB };
26 #define CACHE_NR_REGS 3
27 /* No variant has more than 24 GPIOs */
28 #define CACHE_NR_BANKS (24 / 8)
31 struct gpio_chip chip;
34 struct mutex irq_lock;
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];
41 static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset)
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);
49 ret = stmpe_reg_read(stmpe, reg);
53 return !!(ret & mask);
56 static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
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);
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.
68 if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB])
69 stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
71 stmpe_reg_write(stmpe, reg, mask);
74 static int stmpe_gpio_get_direction(struct gpio_chip *chip,
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);
83 ret = stmpe_reg_read(stmpe, reg);
88 return GPIO_LINE_DIRECTION_OUT;
90 return GPIO_LINE_DIRECTION_IN;
93 static int stmpe_gpio_direction_output(struct gpio_chip *chip,
94 unsigned offset, int val)
96 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
97 struct stmpe *stmpe = stmpe_gpio->stmpe;
98 u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
99 u8 mask = BIT(offset % 8);
101 stmpe_gpio_set(chip, offset, val);
103 return stmpe_set_bits(stmpe, reg, mask, mask);
106 static int stmpe_gpio_direction_input(struct gpio_chip *chip,
109 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
110 struct stmpe *stmpe = stmpe_gpio->stmpe;
111 u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB + (offset / 8)];
112 u8 mask = BIT(offset % 8);
114 return stmpe_set_bits(stmpe, reg, mask, 0);
117 static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset)
119 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(chip);
120 struct stmpe *stmpe = stmpe_gpio->stmpe;
122 if (stmpe_gpio->norequest_mask & BIT(offset))
125 return stmpe_set_altfunc(stmpe, BIT(offset), STMPE_BLOCK_GPIO);
128 static const struct gpio_chip template_chip = {
130 .owner = THIS_MODULE,
131 .get_direction = stmpe_gpio_get_direction,
132 .direction_input = stmpe_gpio_direction_input,
133 .get = stmpe_gpio_get,
134 .direction_output = stmpe_gpio_direction_output,
135 .set = stmpe_gpio_set,
136 .request = stmpe_gpio_request,
140 static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
142 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
143 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
144 int offset = d->hwirq;
145 int regoffset = offset / 8;
146 int mask = BIT(offset % 8);
148 if (type & IRQ_TYPE_LEVEL_LOW || type & IRQ_TYPE_LEVEL_HIGH)
151 /* STMPE801 and STMPE 1600 don't have RE and FE registers */
152 if (stmpe_gpio->stmpe->partnum == STMPE801 ||
153 stmpe_gpio->stmpe->partnum == STMPE1600)
156 if (type & IRQ_TYPE_EDGE_RISING)
157 stmpe_gpio->regs[REG_RE][regoffset] |= mask;
159 stmpe_gpio->regs[REG_RE][regoffset] &= ~mask;
161 if (type & IRQ_TYPE_EDGE_FALLING)
162 stmpe_gpio->regs[REG_FE][regoffset] |= mask;
164 stmpe_gpio->regs[REG_FE][regoffset] &= ~mask;
169 static void stmpe_gpio_irq_lock(struct irq_data *d)
171 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
172 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
174 mutex_lock(&stmpe_gpio->irq_lock);
177 static void stmpe_gpio_irq_sync_unlock(struct irq_data *d)
179 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
180 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
181 struct stmpe *stmpe = stmpe_gpio->stmpe;
182 int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
183 static const u8 regmap[CACHE_NR_REGS][CACHE_NR_BANKS] = {
184 [REG_RE][LSB] = STMPE_IDX_GPRER_LSB,
185 [REG_RE][CSB] = STMPE_IDX_GPRER_CSB,
186 [REG_RE][MSB] = STMPE_IDX_GPRER_MSB,
187 [REG_FE][LSB] = STMPE_IDX_GPFER_LSB,
188 [REG_FE][CSB] = STMPE_IDX_GPFER_CSB,
189 [REG_FE][MSB] = STMPE_IDX_GPFER_MSB,
190 [REG_IE][LSB] = STMPE_IDX_IEGPIOR_LSB,
191 [REG_IE][CSB] = STMPE_IDX_IEGPIOR_CSB,
192 [REG_IE][MSB] = STMPE_IDX_IEGPIOR_MSB,
197 * STMPE1600: to be able to get IRQ from pins,
198 * a read must be done on GPMR register, or a write in
199 * GPSR or GPCR registers
201 if (stmpe->partnum == STMPE1600) {
202 stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_LSB]);
203 stmpe_reg_read(stmpe, stmpe->regs[STMPE_IDX_GPMR_CSB]);
206 for (i = 0; i < CACHE_NR_REGS; i++) {
207 /* STMPE801 and STMPE1600 don't have RE and FE registers */
208 if ((stmpe->partnum == STMPE801 ||
209 stmpe->partnum == STMPE1600) &&
213 for (j = 0; j < num_banks; j++) {
214 u8 old = stmpe_gpio->oldregs[i][j];
215 u8 new = stmpe_gpio->regs[i][j];
220 stmpe_gpio->oldregs[i][j] = new;
221 stmpe_reg_write(stmpe, stmpe->regs[regmap[i][j]], new);
225 mutex_unlock(&stmpe_gpio->irq_lock);
228 static void stmpe_gpio_irq_mask(struct irq_data *d)
230 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
231 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
232 int offset = d->hwirq;
233 int regoffset = offset / 8;
234 int mask = BIT(offset % 8);
236 stmpe_gpio->regs[REG_IE][regoffset] &= ~mask;
239 static void stmpe_gpio_irq_unmask(struct irq_data *d)
241 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
242 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
243 int offset = d->hwirq;
244 int regoffset = offset / 8;
245 int mask = BIT(offset % 8);
247 stmpe_gpio->regs[REG_IE][regoffset] |= mask;
250 static void stmpe_dbg_show_one(struct seq_file *s,
251 struct gpio_chip *gc,
252 unsigned offset, unsigned gpio)
254 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
255 struct stmpe *stmpe = stmpe_gpio->stmpe;
256 const char *label = gpiochip_is_requested(gc, offset);
257 bool val = !!stmpe_gpio_get(gc, offset);
258 u8 bank = offset / 8;
259 u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB + bank];
260 u8 mask = BIT(offset % 8);
264 ret = stmpe_reg_read(stmpe, dir_reg);
267 dir = !!(ret & mask);
270 seq_printf(s, " gpio-%-3d (%-20.20s) out %s",
271 gpio, label ?: "(none)",
279 static const char * const edge_det_values[] = {
284 static const char * const rise_values[] = {
285 "no-rising-edge-detection",
286 "rising-edge-detection",
289 static const char * const fall_values[] = {
290 "no-falling-edge-detection",
291 "falling-edge-detection",
294 #define NOT_SUPPORTED_IDX 2
295 u8 edge_det = NOT_SUPPORTED_IDX;
296 u8 rise = NOT_SUPPORTED_IDX;
297 u8 fall = NOT_SUPPORTED_IDX;
300 switch (stmpe->partnum) {
306 edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_LSB + bank];
307 ret = stmpe_reg_read(stmpe, edge_det_reg);
310 edge_det = !!(ret & mask);
313 rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB + bank];
314 fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB + bank];
316 ret = stmpe_reg_read(stmpe, rise_reg);
319 rise = !!(ret & mask);
320 ret = stmpe_reg_read(stmpe, fall_reg);
323 fall = !!(ret & mask);
327 irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB + bank];
334 ret = stmpe_reg_read(stmpe, irqen_reg);
337 irqen = !!(ret & mask);
339 seq_printf(s, " gpio-%-3d (%-20.20s) in %s %13s %13s %25s %25s",
340 gpio, label ?: "(none)",
342 edge_det_values[edge_det],
343 irqen ? "IRQ-enabled" : "IRQ-disabled",
349 static void stmpe_dbg_show(struct seq_file *s, struct gpio_chip *gc)
352 unsigned gpio = gc->base;
354 for (i = 0; i < gc->ngpio; i++, gpio++) {
355 stmpe_dbg_show_one(s, gc, i, gpio);
360 static struct irq_chip stmpe_gpio_irq_chip = {
361 .name = "stmpe-gpio",
362 .irq_bus_lock = stmpe_gpio_irq_lock,
363 .irq_bus_sync_unlock = stmpe_gpio_irq_sync_unlock,
364 .irq_mask = stmpe_gpio_irq_mask,
365 .irq_unmask = stmpe_gpio_irq_unmask,
366 .irq_set_type = stmpe_gpio_irq_set_type,
371 static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
373 struct stmpe_gpio *stmpe_gpio = dev;
374 struct stmpe *stmpe = stmpe_gpio->stmpe;
376 int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
377 u8 status[DIV_ROUND_UP(MAX_GPIOS, 8)];
382 * the stmpe_block_read() call below, imposes to set statmsbreg
383 * with the register located at the lowest address. As STMPE1600
384 * variant is the only one which respect registers address's order
385 * (LSB regs located at lowest address than MSB ones) whereas all
386 * the others have a registers layout with MSB located before the
389 if (stmpe->partnum == STMPE1600)
390 statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_LSB];
392 statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB];
394 ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status);
398 for (i = 0; i < num_banks; i++) {
399 int bank = (stmpe_gpio->stmpe->partnum == STMPE1600) ? i :
401 unsigned int enabled = stmpe_gpio->regs[REG_IE][bank];
402 unsigned int stat = status[i];
409 int bit = __ffs(stat);
410 int line = bank * 8 + bit;
411 int child_irq = irq_find_mapping(stmpe_gpio->chip.irq.domain,
414 handle_nested_irq(child_irq);
419 * interrupt status register write has no effect on
420 * 801/1801/1600, bits are cleared when read.
421 * Edge detect register is not present on 801/1600/1801
423 if (stmpe->partnum != STMPE801 && stmpe->partnum != STMPE1600 &&
424 stmpe->partnum != STMPE1801) {
425 stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
426 stmpe_reg_write(stmpe,
427 stmpe->regs[STMPE_IDX_GPEDR_MSB] + i,
435 static void stmpe_init_irq_valid_mask(struct gpio_chip *gc,
436 unsigned long *valid_mask,
439 struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
442 if (!stmpe_gpio->norequest_mask)
445 /* Forbid unused lines to be mapped as IRQs */
446 for (i = 0; i < sizeof(u32); i++) {
447 if (stmpe_gpio->norequest_mask & BIT(i))
448 clear_bit(i, valid_mask);
452 static int stmpe_gpio_probe(struct platform_device *pdev)
454 struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
455 struct device_node *np = pdev->dev.of_node;
456 struct stmpe_gpio *stmpe_gpio;
459 if (stmpe->num_gpios > MAX_GPIOS) {
460 dev_err(&pdev->dev, "Need to increase maximum GPIO number\n");
464 stmpe_gpio = kzalloc(sizeof(*stmpe_gpio), GFP_KERNEL);
468 mutex_init(&stmpe_gpio->irq_lock);
470 stmpe_gpio->dev = &pdev->dev;
471 stmpe_gpio->stmpe = stmpe;
472 stmpe_gpio->chip = template_chip;
473 stmpe_gpio->chip.ngpio = stmpe->num_gpios;
474 stmpe_gpio->chip.parent = &pdev->dev;
475 stmpe_gpio->chip.of_node = np;
476 stmpe_gpio->chip.base = -1;
478 if (IS_ENABLED(CONFIG_DEBUG_FS))
479 stmpe_gpio->chip.dbg_show = stmpe_dbg_show;
481 of_property_read_u32(np, "st,norequest-mask",
482 &stmpe_gpio->norequest_mask);
484 irq = platform_get_irq(pdev, 0);
487 "device configured in no-irq mode: "
488 "irqs are not available\n");
490 ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
495 struct gpio_irq_chip *girq;
497 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
498 stmpe_gpio_irq, IRQF_ONESHOT,
499 "stmpe-gpio", stmpe_gpio);
501 dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
505 girq = &stmpe_gpio->chip.irq;
506 girq->chip = &stmpe_gpio_irq_chip;
507 /* This will let us handle the parent IRQ in the driver */
508 girq->parent_handler = NULL;
509 girq->num_parents = 0;
510 girq->parents = NULL;
511 girq->default_type = IRQ_TYPE_NONE;
512 girq->handler = handle_simple_irq;
513 girq->threaded = true;
514 girq->init_valid_mask = stmpe_init_irq_valid_mask;
517 ret = gpiochip_add_data(&stmpe_gpio->chip, stmpe_gpio);
519 dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
523 platform_set_drvdata(pdev, stmpe_gpio);
528 stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
529 gpiochip_remove(&stmpe_gpio->chip);
535 static struct platform_driver stmpe_gpio_driver = {
537 .suppress_bind_attrs = true,
538 .name = "stmpe-gpio",
540 .probe = stmpe_gpio_probe,
543 static int __init stmpe_gpio_init(void)
545 return platform_driver_register(&stmpe_gpio_driver);
547 subsys_initcall(stmpe_gpio_init);