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 * Static mapping of GPIO bank F IRQS:
33 * F0..F7 (16..24) to irq 80..87.
35 #define EP93XX_GPIO_F_IRQ_BASE 80
39 struct gpio_chip gc
[8];
42 /*************************************************************************
43 * Interrupt handling for EP93xx on-chip GPIOs
44 *************************************************************************/
45 static unsigned char gpio_int_unmasked
[3];
46 static unsigned char gpio_int_enabled
[3];
47 static unsigned char gpio_int_type1
[3];
48 static unsigned char gpio_int_type2
[3];
49 static unsigned char gpio_int_debounce
[3];
51 /* Port ordering is: A B F */
52 static const u8 int_type1_register_offset
[3] = { 0x90, 0xac, 0x4c };
53 static const u8 int_type2_register_offset
[3] = { 0x94, 0xb0, 0x50 };
54 static const u8 eoi_register_offset
[3] = { 0x98, 0xb4, 0x54 };
55 static const u8 int_en_register_offset
[3] = { 0x9c, 0xb8, 0x58 };
56 static const u8 int_debounce_register_offset
[3] = { 0xa8, 0xc4, 0x64 };
58 static void ep93xx_gpio_update_int_params(struct ep93xx_gpio
*epg
, unsigned port
)
62 writeb_relaxed(0, epg
->base
+ int_en_register_offset
[port
]);
64 writeb_relaxed(gpio_int_type2
[port
],
65 epg
->base
+ int_type2_register_offset
[port
]);
67 writeb_relaxed(gpio_int_type1
[port
],
68 epg
->base
+ int_type1_register_offset
[port
]);
70 writeb(gpio_int_unmasked
[port
] & gpio_int_enabled
[port
],
71 epg
->base
+ int_en_register_offset
[port
]);
74 static int ep93xx_gpio_port(struct gpio_chip
*gc
)
76 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
79 while (port
< ARRAY_SIZE(epg
->gc
) && gc
!= &epg
->gc
[port
])
82 /* This should not happen but is there as a last safeguard */
83 if (port
== ARRAY_SIZE(epg
->gc
)) {
84 pr_crit("can't find the GPIO port\n");
91 static void ep93xx_gpio_int_debounce(struct gpio_chip
*gc
,
92 unsigned int offset
, bool enable
)
94 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
95 int port
= ep93xx_gpio_port(gc
);
96 int port_mask
= BIT(offset
);
99 gpio_int_debounce
[port
] |= port_mask
;
101 gpio_int_debounce
[port
] &= ~port_mask
;
103 writeb(gpio_int_debounce
[port
],
104 epg
->base
+ int_debounce_register_offset
[port
]);
107 static void ep93xx_gpio_ab_irq_handler(struct irq_desc
*desc
)
109 struct gpio_chip
*gc
= irq_desc_get_handler_data(desc
);
110 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
111 struct irq_chip
*irqchip
= irq_desc_get_chip(desc
);
115 chained_irq_enter(irqchip
, desc
);
118 * Dispatch the IRQs to the irqdomain of each A and B
119 * gpiochip irqdomains depending on what has fired.
120 * The tricky part is that the IRQ line is shared
121 * between bank A and B and each has their own gpiochip.
123 stat
= readb(epg
->base
+ EP93XX_GPIO_A_INT_STATUS
);
124 for_each_set_bit(offset
, &stat
, 8)
125 generic_handle_irq(irq_find_mapping(epg
->gc
[0].irq
.domain
,
128 stat
= readb(epg
->base
+ EP93XX_GPIO_B_INT_STATUS
);
129 for_each_set_bit(offset
, &stat
, 8)
130 generic_handle_irq(irq_find_mapping(epg
->gc
[1].irq
.domain
,
133 chained_irq_exit(irqchip
, desc
);
136 static void ep93xx_gpio_f_irq_handler(struct irq_desc
*desc
)
139 * map discontiguous hw irq range to continuous sw irq range:
141 * IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7}
143 struct irq_chip
*irqchip
= irq_desc_get_chip(desc
);
144 unsigned int irq
= irq_desc_get_irq(desc
);
145 int port_f_idx
= ((irq
+ 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */
146 int gpio_irq
= EP93XX_GPIO_F_IRQ_BASE
+ port_f_idx
;
148 chained_irq_enter(irqchip
, desc
);
149 generic_handle_irq(gpio_irq
);
150 chained_irq_exit(irqchip
, desc
);
153 static void ep93xx_gpio_irq_ack(struct irq_data
*d
)
155 struct gpio_chip
*gc
= irq_data_get_irq_chip_data(d
);
156 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
157 int port
= ep93xx_gpio_port(gc
);
158 int port_mask
= BIT(d
->irq
& 7);
160 if (irqd_get_trigger_type(d
) == IRQ_TYPE_EDGE_BOTH
) {
161 gpio_int_type2
[port
] ^= port_mask
; /* switch edge direction */
162 ep93xx_gpio_update_int_params(epg
, port
);
165 writeb(port_mask
, epg
->base
+ eoi_register_offset
[port
]);
168 static void ep93xx_gpio_irq_mask_ack(struct irq_data
*d
)
170 struct gpio_chip
*gc
= irq_data_get_irq_chip_data(d
);
171 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
172 int port
= ep93xx_gpio_port(gc
);
173 int port_mask
= BIT(d
->irq
& 7);
175 if (irqd_get_trigger_type(d
) == IRQ_TYPE_EDGE_BOTH
)
176 gpio_int_type2
[port
] ^= port_mask
; /* switch edge direction */
178 gpio_int_unmasked
[port
] &= ~port_mask
;
179 ep93xx_gpio_update_int_params(epg
, port
);
181 writeb(port_mask
, epg
->base
+ eoi_register_offset
[port
]);
184 static void ep93xx_gpio_irq_mask(struct irq_data
*d
)
186 struct gpio_chip
*gc
= irq_data_get_irq_chip_data(d
);
187 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
188 int port
= ep93xx_gpio_port(gc
);
190 gpio_int_unmasked
[port
] &= ~BIT(d
->irq
& 7);
191 ep93xx_gpio_update_int_params(epg
, port
);
194 static void ep93xx_gpio_irq_unmask(struct irq_data
*d
)
196 struct gpio_chip
*gc
= irq_data_get_irq_chip_data(d
);
197 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
198 int port
= ep93xx_gpio_port(gc
);
200 gpio_int_unmasked
[port
] |= BIT(d
->irq
& 7);
201 ep93xx_gpio_update_int_params(epg
, port
);
205 * gpio_int_type1 controls whether the interrupt is level (0) or
206 * edge (1) triggered, while gpio_int_type2 controls whether it
207 * triggers on low/falling (0) or high/rising (1).
209 static int ep93xx_gpio_irq_type(struct irq_data
*d
, unsigned int type
)
211 struct gpio_chip
*gc
= irq_data_get_irq_chip_data(d
);
212 struct ep93xx_gpio
*epg
= gpiochip_get_data(gc
);
213 int port
= ep93xx_gpio_port(gc
);
214 int offset
= d
->irq
& 7;
215 int port_mask
= BIT(offset
);
216 irq_flow_handler_t handler
;
218 gc
->direction_input(gc
, offset
);
221 case IRQ_TYPE_EDGE_RISING
:
222 gpio_int_type1
[port
] |= port_mask
;
223 gpio_int_type2
[port
] |= port_mask
;
224 handler
= handle_edge_irq
;
226 case IRQ_TYPE_EDGE_FALLING
:
227 gpio_int_type1
[port
] |= port_mask
;
228 gpio_int_type2
[port
] &= ~port_mask
;
229 handler
= handle_edge_irq
;
231 case IRQ_TYPE_LEVEL_HIGH
:
232 gpio_int_type1
[port
] &= ~port_mask
;
233 gpio_int_type2
[port
] |= port_mask
;
234 handler
= handle_level_irq
;
236 case IRQ_TYPE_LEVEL_LOW
:
237 gpio_int_type1
[port
] &= ~port_mask
;
238 gpio_int_type2
[port
] &= ~port_mask
;
239 handler
= handle_level_irq
;
241 case IRQ_TYPE_EDGE_BOTH
:
242 gpio_int_type1
[port
] |= port_mask
;
243 /* set initial polarity based on current input level */
244 if (gc
->get(gc
, offset
))
245 gpio_int_type2
[port
] &= ~port_mask
; /* falling */
247 gpio_int_type2
[port
] |= port_mask
; /* rising */
248 handler
= handle_edge_irq
;
254 irq_set_handler_locked(d
, handler
);
256 gpio_int_enabled
[port
] |= port_mask
;
258 ep93xx_gpio_update_int_params(epg
, port
);
263 static struct irq_chip ep93xx_gpio_irq_chip
= {
265 .irq_ack
= ep93xx_gpio_irq_ack
,
266 .irq_mask_ack
= ep93xx_gpio_irq_mask_ack
,
267 .irq_mask
= ep93xx_gpio_irq_mask
,
268 .irq_unmask
= ep93xx_gpio_irq_unmask
,
269 .irq_set_type
= ep93xx_gpio_irq_type
,
272 static int ep93xx_gpio_init_irq(struct platform_device
*pdev
,
273 struct ep93xx_gpio
*epg
)
275 int ab_parent_irq
= platform_get_irq(pdev
, 0);
276 struct device
*dev
= &pdev
->dev
;
282 ret
= gpiochip_irqchip_add(&epg
->gc
[0], &ep93xx_gpio_irq_chip
,
283 64, handle_level_irq
,
286 dev_err(dev
, "Could not add irqchip 0\n");
289 gpiochip_set_chained_irqchip(&epg
->gc
[0], &ep93xx_gpio_irq_chip
,
291 ep93xx_gpio_ab_irq_handler
);
294 ret
= gpiochip_irqchip_add(&epg
->gc
[1], &ep93xx_gpio_irq_chip
,
295 72, handle_level_irq
,
298 dev_err(dev
, "Could not add irqchip 1\n");
301 gpiochip_set_chained_irqchip(&epg
->gc
[1], &ep93xx_gpio_irq_chip
,
303 ep93xx_gpio_ab_irq_handler
);
306 for (i
= 0; i
< 8; i
++) {
307 gpio_irq
= EP93XX_GPIO_F_IRQ_BASE
+ i
;
308 irq_set_chip_data(gpio_irq
, &epg
->gc
[5]);
309 irq_set_chip_and_handler(gpio_irq
, &ep93xx_gpio_irq_chip
,
311 irq_clear_status_flags(gpio_irq
, IRQ_NOREQUEST
);
314 for (i
= 1; i
<= 8; i
++)
315 irq_set_chained_handler_and_data(platform_get_irq(pdev
, i
),
316 ep93xx_gpio_f_irq_handler
,
322 /*************************************************************************
323 * gpiolib interface for EP93xx on-chip GPIOs
324 *************************************************************************/
325 struct ep93xx_gpio_bank
{
333 #define EP93XX_GPIO_BANK(_label, _data, _dir, _base, _has_irq) \
339 .has_irq = _has_irq, \
342 static struct ep93xx_gpio_bank ep93xx_gpio_banks
[] = {
343 EP93XX_GPIO_BANK("A", 0x00, 0x10, 0, true), /* Bank A has 8 IRQs */
344 EP93XX_GPIO_BANK("B", 0x04, 0x14, 8, true), /* Bank B has 8 IRQs */
345 EP93XX_GPIO_BANK("C", 0x08, 0x18, 40, false),
346 EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24, false),
347 EP93XX_GPIO_BANK("E", 0x20, 0x24, 32, false),
348 EP93XX_GPIO_BANK("F", 0x30, 0x34, 16, true), /* Bank F has 8 IRQs */
349 EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48, false),
350 EP93XX_GPIO_BANK("H", 0x40, 0x44, 56, false),
353 static int ep93xx_gpio_set_config(struct gpio_chip
*gc
, unsigned offset
,
354 unsigned long config
)
358 if (pinconf_to_config_param(config
) != PIN_CONFIG_INPUT_DEBOUNCE
)
361 debounce
= pinconf_to_config_argument(config
);
362 ep93xx_gpio_int_debounce(gc
, offset
, debounce
? true : false);
367 static int ep93xx_gpio_f_to_irq(struct gpio_chip
*gc
, unsigned offset
)
369 return EP93XX_GPIO_F_IRQ_BASE
+ offset
;
372 static int ep93xx_gpio_add_bank(struct gpio_chip
*gc
, struct device
*dev
,
373 struct ep93xx_gpio
*epg
,
374 struct ep93xx_gpio_bank
*bank
)
376 void __iomem
*data
= epg
->base
+ bank
->data
;
377 void __iomem
*dir
= epg
->base
+ bank
->dir
;
380 err
= bgpio_init(gc
, dev
, 1, data
, NULL
, NULL
, dir
, NULL
, 0);
384 gc
->label
= bank
->label
;
385 gc
->base
= bank
->base
;
388 gc
->set_config
= ep93xx_gpio_set_config
;
390 return devm_gpiochip_add_data(dev
, gc
, epg
);
393 static int ep93xx_gpio_probe(struct platform_device
*pdev
)
395 struct ep93xx_gpio
*epg
;
396 struct resource
*res
;
398 struct device
*dev
= &pdev
->dev
;
400 epg
= devm_kzalloc(dev
, sizeof(*epg
), GFP_KERNEL
);
404 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
405 epg
->base
= devm_ioremap_resource(dev
, res
);
406 if (IS_ERR(epg
->base
))
407 return PTR_ERR(epg
->base
);
409 for (i
= 0; i
< ARRAY_SIZE(ep93xx_gpio_banks
); i
++) {
410 struct gpio_chip
*gc
= &epg
->gc
[i
];
411 struct ep93xx_gpio_bank
*bank
= &ep93xx_gpio_banks
[i
];
413 if (ep93xx_gpio_add_bank(gc
, &pdev
->dev
, epg
, bank
))
414 dev_warn(&pdev
->dev
, "Unable to add gpio bank %s\n",
416 /* Only bank F has especially funky IRQ handling */
418 gc
->to_irq
= ep93xx_gpio_f_to_irq
;
421 ep93xx_gpio_init_irq(pdev
, epg
);
426 static struct platform_driver ep93xx_gpio_driver
= {
428 .name
= "gpio-ep93xx",
430 .probe
= ep93xx_gpio_probe
,
433 static int __init
ep93xx_gpio_init(void)
435 return platform_driver_register(&ep93xx_gpio_driver
);
437 postcore_initcall(ep93xx_gpio_init
);
439 MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com> "
440 "H Hartley Sweeten <hsweeten@visionengravers.com>");
441 MODULE_DESCRIPTION("EP93XX GPIO driver");
442 MODULE_LICENSE("GPL");