1 // SPDX-License-Identifier: GPL-2.0
3 * Generic EP93xx GPIO handling
5 * Copyright (c) 2008 Ryan Mallon
6 * Copyright (c) 2011 H Hartley Sweeten <hsweeten@visionengravers.com>
8 * Based on code originally from:
9 * linux/arch/arm/mach-ep93xx/core.c
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
16 #include <linux/irq.h>
17 #include <linux/slab.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/bitops.h>
21 #define EP93XX_GPIO_F_INT_STATUS 0x5c
22 #define EP93XX_GPIO_A_INT_STATUS 0xa0
23 #define EP93XX_GPIO_B_INT_STATUS 0xbc
25 /* Maximum value for gpio line identifiers */
26 #define EP93XX_GPIO_LINE_MAX 63
28 /* Maximum value for irq capable line identifiers */
29 #define EP93XX_GPIO_LINE_MAX_IRQ 23
32 * IRQ numbers used by this driver is 64 ..87
34 * Map GPIO A0..A7 (0..7) to irq 64..71,
35 * B0..B7 (7..15) to irq 72..79, and
36 * F0..F7 (16..24) to irq 80..87.
38 static unsigned int ep93xx_gpio_irq_base[3] = { 64, 72, 80 };
42 struct gpio_chip gc[8];
45 /*************************************************************************
46 * Interrupt handling for EP93xx on-chip GPIOs
47 *************************************************************************/
48 static unsigned char gpio_int_unmasked[3];
49 static unsigned char gpio_int_enabled[3];
50 static unsigned char gpio_int_type1[3];
51 static unsigned char gpio_int_type2[3];
52 static unsigned char gpio_int_debounce[3];
54 /* Port ordering is: A B F */
55 static const u8 int_type1_register_offset[3] = { 0x90, 0xac, 0x4c };
56 static const u8 int_type2_register_offset[3] = { 0x94, 0xb0, 0x50 };
57 static const u8 eoi_register_offset[3] = { 0x98, 0xb4, 0x54 };
58 static const u8 int_en_register_offset[3] = { 0x9c, 0xb8, 0x58 };
59 static const u8 int_debounce_register_offset[3] = { 0xa8, 0xc4, 0x64 };
61 static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg, unsigned port)
65 writeb_relaxed(0, epg->base + int_en_register_offset[port]);
67 writeb_relaxed(gpio_int_type2[port],
68 epg->base + int_type2_register_offset[port]);
70 writeb_relaxed(gpio_int_type1[port],
71 epg->base + int_type1_register_offset[port]);
73 writeb(gpio_int_unmasked[port] & gpio_int_enabled[port],
74 epg->base + int_en_register_offset[port]);
77 static int ep93xx_gpio_port(struct gpio_chip *gc)
79 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
82 while (gc != &epg->gc[port] && port < sizeof(epg->gc))
85 /* This should not happen but is there as a last safeguard */
86 if (gc != &epg->gc[port]) {
87 pr_crit("can't find the GPIO port\n");
94 static void ep93xx_gpio_int_debounce(struct gpio_chip *gc,
95 unsigned int offset, bool enable)
97 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
98 int port = ep93xx_gpio_port(gc);
99 int port_mask = BIT(offset);
102 gpio_int_debounce[port] |= port_mask;
104 gpio_int_debounce[port] &= ~port_mask;
106 writeb(gpio_int_debounce[port],
107 epg->base + int_debounce_register_offset[port]);
110 static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
112 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
113 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
114 struct irq_chip *irqchip = irq_desc_get_chip(desc);
118 chained_irq_enter(irqchip, desc);
120 stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS);
121 for_each_set_bit(offset, &stat, 8) {
122 int gpio_irq = ep93xx_gpio_irq_base[0] + offset;
123 generic_handle_irq(gpio_irq);
126 stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS);
127 for_each_set_bit(offset, &stat, 8) {
128 int gpio_irq = ep93xx_gpio_irq_base[1] + offset;
129 generic_handle_irq(gpio_irq);
132 chained_irq_exit(irqchip, desc);
135 static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc)
138 * map discontiguous hw irq range to continuous sw irq range:
140 * IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7}
142 struct irq_chip *irqchip = irq_desc_get_chip(desc);
143 unsigned int irq = irq_desc_get_irq(desc);
144 int port_f_idx = ((irq + 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */
145 int gpio_irq = ep93xx_gpio_irq_base[2] + port_f_idx;
147 chained_irq_enter(irqchip, desc);
148 generic_handle_irq(gpio_irq);
149 chained_irq_exit(irqchip, desc);
152 static void ep93xx_gpio_irq_ack(struct irq_data *d)
154 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
155 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
156 int port = ep93xx_gpio_port(gc);
157 int port_mask = BIT(d->irq & 7);
159 if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) {
160 gpio_int_type2[port] ^= port_mask; /* switch edge direction */
161 ep93xx_gpio_update_int_params(epg, port);
164 writeb(port_mask, epg->base + eoi_register_offset[port]);
167 static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
169 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
170 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
171 int port = ep93xx_gpio_port(gc);
172 int port_mask = BIT(d->irq & 7);
174 if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH)
175 gpio_int_type2[port] ^= port_mask; /* switch edge direction */
177 gpio_int_unmasked[port] &= ~port_mask;
178 ep93xx_gpio_update_int_params(epg, port);
180 writeb(port_mask, epg->base + eoi_register_offset[port]);
183 static void ep93xx_gpio_irq_mask(struct irq_data *d)
185 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
186 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
187 int port = ep93xx_gpio_port(gc);
189 gpio_int_unmasked[port] &= ~BIT(d->irq & 7);
190 ep93xx_gpio_update_int_params(epg, port);
193 static void ep93xx_gpio_irq_unmask(struct irq_data *d)
195 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
196 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
197 int port = ep93xx_gpio_port(gc);
199 gpio_int_unmasked[port] |= BIT(d->irq & 7);
200 ep93xx_gpio_update_int_params(epg, port);
204 * gpio_int_type1 controls whether the interrupt is level (0) or
205 * edge (1) triggered, while gpio_int_type2 controls whether it
206 * triggers on low/falling (0) or high/rising (1).
208 static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)
210 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
211 struct ep93xx_gpio *epg = gpiochip_get_data(gc);
212 int port = ep93xx_gpio_port(gc);
213 int offset = d->irq & 7;
214 int port_mask = BIT(offset);
215 irq_flow_handler_t handler;
217 gc->direction_input(gc, offset);
220 case IRQ_TYPE_EDGE_RISING:
221 gpio_int_type1[port] |= port_mask;
222 gpio_int_type2[port] |= port_mask;
223 handler = handle_edge_irq;
225 case IRQ_TYPE_EDGE_FALLING:
226 gpio_int_type1[port] |= port_mask;
227 gpio_int_type2[port] &= ~port_mask;
228 handler = handle_edge_irq;
230 case IRQ_TYPE_LEVEL_HIGH:
231 gpio_int_type1[port] &= ~port_mask;
232 gpio_int_type2[port] |= port_mask;
233 handler = handle_level_irq;
235 case IRQ_TYPE_LEVEL_LOW:
236 gpio_int_type1[port] &= ~port_mask;
237 gpio_int_type2[port] &= ~port_mask;
238 handler = handle_level_irq;
240 case IRQ_TYPE_EDGE_BOTH:
241 gpio_int_type1[port] |= port_mask;
242 /* set initial polarity based on current input level */
243 if (gc->get(gc, offset))
244 gpio_int_type2[port] &= ~port_mask; /* falling */
246 gpio_int_type2[port] |= port_mask; /* rising */
247 handler = handle_edge_irq;
253 irq_set_handler_locked(d, handler);
255 gpio_int_enabled[port] |= port_mask;
257 ep93xx_gpio_update_int_params(epg, port);
262 static struct irq_chip ep93xx_gpio_irq_chip = {
264 .irq_ack = ep93xx_gpio_irq_ack,
265 .irq_mask_ack = ep93xx_gpio_irq_mask_ack,
266 .irq_mask = ep93xx_gpio_irq_mask,
267 .irq_unmask = ep93xx_gpio_irq_unmask,
268 .irq_set_type = ep93xx_gpio_irq_type,
271 static void ep93xx_gpio_init_irq(struct platform_device *pdev,
272 struct ep93xx_gpio *epg)
278 for (i = 0; i < 8; i++) {
279 gpio_irq = ep93xx_gpio_irq_base[0] + i;
280 irq_set_chip_data(gpio_irq, &epg->gc[0]);
281 irq_set_chip_and_handler(gpio_irq, &ep93xx_gpio_irq_chip,
283 irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST);
286 for (i = 0; i < 8; i++) {
287 gpio_irq = ep93xx_gpio_irq_base[1] + i;
288 irq_set_chip_data(gpio_irq, &epg->gc[1]);
289 irq_set_chip_and_handler(gpio_irq, &ep93xx_gpio_irq_chip,
291 irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST);
294 for (i = 0; i < 8; i++) {
295 gpio_irq = ep93xx_gpio_irq_base[2] + i;
296 irq_set_chip_data(gpio_irq, &epg->gc[5]);
297 irq_set_chip_and_handler(gpio_irq, &ep93xx_gpio_irq_chip,
299 irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST);
302 irq_set_chained_handler_and_data(platform_get_irq(pdev, 0),
303 ep93xx_gpio_ab_irq_handler,
305 for (i = 1; i <= 8; i++)
306 irq_set_chained_handler_and_data(platform_get_irq(pdev, i),
307 ep93xx_gpio_f_irq_handler,
312 /*************************************************************************
313 * gpiolib interface for EP93xx on-chip GPIOs
314 *************************************************************************/
315 struct ep93xx_gpio_bank {
323 #define EP93XX_GPIO_BANK(_label, _data, _dir, _base, _has_irq) \
329 .has_irq = _has_irq, \
332 static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = {
333 EP93XX_GPIO_BANK("A", 0x00, 0x10, 0, true), /* Bank A has 8 IRQs */
334 EP93XX_GPIO_BANK("B", 0x04, 0x14, 8, true), /* Bank B has 8 IRQs */
335 EP93XX_GPIO_BANK("C", 0x08, 0x18, 40, false),
336 EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24, false),
337 EP93XX_GPIO_BANK("E", 0x20, 0x24, 32, false),
338 EP93XX_GPIO_BANK("F", 0x30, 0x34, 16, true), /* Bank F has 8 IRQs */
339 EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48, false),
340 EP93XX_GPIO_BANK("H", 0x40, 0x44, 56, false),
343 static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset,
344 unsigned long config)
348 if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
351 debounce = pinconf_to_config_argument(config);
352 ep93xx_gpio_int_debounce(gc, offset, debounce ? true : false);
357 static int ep93xx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
359 int port = ep93xx_gpio_port(gc);
361 /* Those are the ports supporting IRQ */
362 if (port != 0 && port != 1 && port != 5)
365 return ep93xx_gpio_irq_base[port] + offset;
368 static int ep93xx_gpio_add_bank(struct gpio_chip *gc, struct device *dev,
369 struct ep93xx_gpio *epg,
370 struct ep93xx_gpio_bank *bank)
372 void __iomem *data = epg->base + bank->data;
373 void __iomem *dir = epg->base + bank->dir;
376 err = bgpio_init(gc, dev, 1, data, NULL, NULL, dir, NULL, 0);
380 gc->label = bank->label;
381 gc->base = bank->base;
384 gc->set_config = ep93xx_gpio_set_config;
385 gc->to_irq = ep93xx_gpio_to_irq;
388 return devm_gpiochip_add_data(dev, gc, epg);
391 static int ep93xx_gpio_probe(struct platform_device *pdev)
393 struct ep93xx_gpio *epg;
394 struct resource *res;
396 struct device *dev = &pdev->dev;
398 epg = devm_kzalloc(dev, sizeof(*epg), GFP_KERNEL);
402 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
403 epg->base = devm_ioremap_resource(dev, res);
404 if (IS_ERR(epg->base))
405 return PTR_ERR(epg->base);
407 for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
408 struct gpio_chip *gc = &epg->gc[i];
409 struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i];
411 if (ep93xx_gpio_add_bank(gc, &pdev->dev, epg, bank))
412 dev_warn(&pdev->dev, "Unable to add gpio bank %s\n",
416 ep93xx_gpio_init_irq(pdev, epg);
421 static struct platform_driver ep93xx_gpio_driver = {
423 .name = "gpio-ep93xx",
425 .probe = ep93xx_gpio_probe,
428 static int __init ep93xx_gpio_init(void)
430 return platform_driver_register(&ep93xx_gpio_driver);
432 postcore_initcall(ep93xx_gpio_init);
434 MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com> "
435 "H Hartley Sweeten <hsweeten@visionengravers.com>");
436 MODULE_DESCRIPTION("EP93XX GPIO driver");
437 MODULE_LICENSE("GPL");