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3242ba11 HK |
1 | /* |
2 | * Xilinx Zynq GPIO device driver | |
3 | * | |
4 | * Copyright (C) 2009 - 2014 Xilinx, Inc. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it under | |
7 | * the terms of the GNU General Public License as published by the Free Software | |
8 | * Foundation; either version 2 of the License, or (at your option) any later | |
9 | * version. | |
10 | */ | |
11 | ||
12 | #include <linux/bitops.h> | |
13 | #include <linux/clk.h> | |
14 | #include <linux/gpio/driver.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/interrupt.h> | |
17 | #include <linux/io.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/platform_device.h> | |
20 | #include <linux/pm_runtime.h> | |
21 | ||
22 | #define DRIVER_NAME "zynq-gpio" | |
23 | ||
24 | /* Maximum banks */ | |
25 | #define ZYNQ_GPIO_MAX_BANK 4 | |
26 | ||
27 | #define ZYNQ_GPIO_BANK0_NGPIO 32 | |
28 | #define ZYNQ_GPIO_BANK1_NGPIO 22 | |
29 | #define ZYNQ_GPIO_BANK2_NGPIO 32 | |
30 | #define ZYNQ_GPIO_BANK3_NGPIO 32 | |
31 | ||
32 | #define ZYNQ_GPIO_NR_GPIOS (ZYNQ_GPIO_BANK0_NGPIO + \ | |
33 | ZYNQ_GPIO_BANK1_NGPIO + \ | |
34 | ZYNQ_GPIO_BANK2_NGPIO + \ | |
35 | ZYNQ_GPIO_BANK3_NGPIO) | |
36 | ||
37 | #define ZYNQ_GPIO_BANK0_PIN_MIN 0 | |
38 | #define ZYNQ_GPIO_BANK0_PIN_MAX (ZYNQ_GPIO_BANK0_PIN_MIN + \ | |
39 | ZYNQ_GPIO_BANK0_NGPIO - 1) | |
40 | #define ZYNQ_GPIO_BANK1_PIN_MIN (ZYNQ_GPIO_BANK0_PIN_MAX + 1) | |
41 | #define ZYNQ_GPIO_BANK1_PIN_MAX (ZYNQ_GPIO_BANK1_PIN_MIN + \ | |
42 | ZYNQ_GPIO_BANK1_NGPIO - 1) | |
43 | #define ZYNQ_GPIO_BANK2_PIN_MIN (ZYNQ_GPIO_BANK1_PIN_MAX + 1) | |
44 | #define ZYNQ_GPIO_BANK2_PIN_MAX (ZYNQ_GPIO_BANK2_PIN_MIN + \ | |
45 | ZYNQ_GPIO_BANK2_NGPIO - 1) | |
46 | #define ZYNQ_GPIO_BANK3_PIN_MIN (ZYNQ_GPIO_BANK2_PIN_MAX + 1) | |
47 | #define ZYNQ_GPIO_BANK3_PIN_MAX (ZYNQ_GPIO_BANK3_PIN_MIN + \ | |
48 | ZYNQ_GPIO_BANK3_NGPIO - 1) | |
49 | ||
50 | ||
51 | /* Register offsets for the GPIO device */ | |
52 | /* LSW Mask & Data -WO */ | |
53 | #define ZYNQ_GPIO_DATA_LSW_OFFSET(BANK) (0x000 + (8 * BANK)) | |
54 | /* MSW Mask & Data -WO */ | |
55 | #define ZYNQ_GPIO_DATA_MSW_OFFSET(BANK) (0x004 + (8 * BANK)) | |
56 | /* Data Register-RW */ | |
57 | #define ZYNQ_GPIO_DATA_RO_OFFSET(BANK) (0x060 + (4 * BANK)) | |
58 | /* Direction mode reg-RW */ | |
59 | #define ZYNQ_GPIO_DIRM_OFFSET(BANK) (0x204 + (0x40 * BANK)) | |
60 | /* Output enable reg-RW */ | |
61 | #define ZYNQ_GPIO_OUTEN_OFFSET(BANK) (0x208 + (0x40 * BANK)) | |
62 | /* Interrupt mask reg-RO */ | |
63 | #define ZYNQ_GPIO_INTMASK_OFFSET(BANK) (0x20C + (0x40 * BANK)) | |
64 | /* Interrupt enable reg-WO */ | |
65 | #define ZYNQ_GPIO_INTEN_OFFSET(BANK) (0x210 + (0x40 * BANK)) | |
66 | /* Interrupt disable reg-WO */ | |
67 | #define ZYNQ_GPIO_INTDIS_OFFSET(BANK) (0x214 + (0x40 * BANK)) | |
68 | /* Interrupt status reg-RO */ | |
69 | #define ZYNQ_GPIO_INTSTS_OFFSET(BANK) (0x218 + (0x40 * BANK)) | |
70 | /* Interrupt type reg-RW */ | |
71 | #define ZYNQ_GPIO_INTTYPE_OFFSET(BANK) (0x21C + (0x40 * BANK)) | |
72 | /* Interrupt polarity reg-RW */ | |
73 | #define ZYNQ_GPIO_INTPOL_OFFSET(BANK) (0x220 + (0x40 * BANK)) | |
74 | /* Interrupt on any, reg-RW */ | |
75 | #define ZYNQ_GPIO_INTANY_OFFSET(BANK) (0x224 + (0x40 * BANK)) | |
76 | ||
77 | /* Disable all interrupts mask */ | |
78 | #define ZYNQ_GPIO_IXR_DISABLE_ALL 0xFFFFFFFF | |
79 | ||
80 | /* Mid pin number of a bank */ | |
81 | #define ZYNQ_GPIO_MID_PIN_NUM 16 | |
82 | ||
83 | /* GPIO upper 16 bit mask */ | |
84 | #define ZYNQ_GPIO_UPPER_MASK 0xFFFF0000 | |
85 | ||
86 | /** | |
87 | * struct zynq_gpio - gpio device private data structure | |
88 | * @chip: instance of the gpio_chip | |
89 | * @base_addr: base address of the GPIO device | |
90 | * @clk: clock resource for this controller | |
91 | */ | |
92 | struct zynq_gpio { | |
93 | struct gpio_chip chip; | |
94 | void __iomem *base_addr; | |
95 | struct clk *clk; | |
96 | }; | |
97 | ||
98 | /** | |
99 | * zynq_gpio_get_bank_pin - Get the bank number and pin number within that bank | |
100 | * for a given pin in the GPIO device | |
101 | * @pin_num: gpio pin number within the device | |
102 | * @bank_num: an output parameter used to return the bank number of the gpio | |
103 | * pin | |
104 | * @bank_pin_num: an output parameter used to return pin number within a bank | |
105 | * for the given gpio pin | |
106 | * | |
107 | * Returns the bank number and pin offset within the bank. | |
108 | */ | |
109 | static inline void zynq_gpio_get_bank_pin(unsigned int pin_num, | |
110 | unsigned int *bank_num, | |
111 | unsigned int *bank_pin_num) | |
112 | { | |
113 | switch (pin_num) { | |
114 | case ZYNQ_GPIO_BANK0_PIN_MIN ... ZYNQ_GPIO_BANK0_PIN_MAX: | |
115 | *bank_num = 0; | |
116 | *bank_pin_num = pin_num; | |
117 | break; | |
118 | case ZYNQ_GPIO_BANK1_PIN_MIN ... ZYNQ_GPIO_BANK1_PIN_MAX: | |
119 | *bank_num = 1; | |
120 | *bank_pin_num = pin_num - ZYNQ_GPIO_BANK1_PIN_MIN; | |
121 | break; | |
122 | case ZYNQ_GPIO_BANK2_PIN_MIN ... ZYNQ_GPIO_BANK2_PIN_MAX: | |
123 | *bank_num = 2; | |
124 | *bank_pin_num = pin_num - ZYNQ_GPIO_BANK2_PIN_MIN; | |
125 | break; | |
126 | case ZYNQ_GPIO_BANK3_PIN_MIN ... ZYNQ_GPIO_BANK3_PIN_MAX: | |
127 | *bank_num = 3; | |
128 | *bank_pin_num = pin_num - ZYNQ_GPIO_BANK3_PIN_MIN; | |
129 | break; | |
130 | default: | |
131 | WARN(true, "invalid GPIO pin number: %u", pin_num); | |
132 | *bank_num = 0; | |
133 | *bank_pin_num = 0; | |
134 | break; | |
135 | } | |
136 | } | |
137 | ||
138 | /** | |
139 | * zynq_gpio_get_value - Get the state of the specified pin of GPIO device | |
140 | * @chip: gpio_chip instance to be worked on | |
141 | * @pin: gpio pin number within the device | |
142 | * | |
143 | * This function reads the state of the specified pin of the GPIO device. | |
144 | * | |
145 | * Return: 0 if the pin is low, 1 if pin is high. | |
146 | */ | |
147 | static int zynq_gpio_get_value(struct gpio_chip *chip, unsigned int pin) | |
148 | { | |
149 | u32 data; | |
150 | unsigned int bank_num, bank_pin_num; | |
151 | struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip); | |
152 | ||
153 | zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num); | |
154 | ||
155 | data = readl_relaxed(gpio->base_addr + | |
156 | ZYNQ_GPIO_DATA_RO_OFFSET(bank_num)); | |
157 | ||
158 | return (data >> bank_pin_num) & 1; | |
159 | } | |
160 | ||
161 | /** | |
162 | * zynq_gpio_set_value - Modify the state of the pin with specified value | |
163 | * @chip: gpio_chip instance to be worked on | |
164 | * @pin: gpio pin number within the device | |
165 | * @state: value used to modify the state of the specified pin | |
166 | * | |
167 | * This function calculates the register offset (i.e to lower 16 bits or | |
168 | * upper 16 bits) based on the given pin number and sets the state of a | |
169 | * gpio pin to the specified value. The state is either 0 or non-zero. | |
170 | */ | |
171 | static void zynq_gpio_set_value(struct gpio_chip *chip, unsigned int pin, | |
172 | int state) | |
173 | { | |
174 | unsigned int reg_offset, bank_num, bank_pin_num; | |
175 | struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip); | |
176 | ||
177 | zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num); | |
178 | ||
179 | if (bank_pin_num >= ZYNQ_GPIO_MID_PIN_NUM) { | |
180 | /* only 16 data bits in bit maskable reg */ | |
181 | bank_pin_num -= ZYNQ_GPIO_MID_PIN_NUM; | |
182 | reg_offset = ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num); | |
183 | } else { | |
184 | reg_offset = ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num); | |
185 | } | |
186 | ||
187 | /* | |
188 | * get the 32 bit value to be written to the mask/data register where | |
189 | * the upper 16 bits is the mask and lower 16 bits is the data | |
190 | */ | |
191 | state = !!state; | |
192 | state = ~(1 << (bank_pin_num + ZYNQ_GPIO_MID_PIN_NUM)) & | |
193 | ((state << bank_pin_num) | ZYNQ_GPIO_UPPER_MASK); | |
194 | ||
195 | writel_relaxed(state, gpio->base_addr + reg_offset); | |
196 | } | |
197 | ||
198 | /** | |
199 | * zynq_gpio_dir_in - Set the direction of the specified GPIO pin as input | |
200 | * @chip: gpio_chip instance to be worked on | |
201 | * @pin: gpio pin number within the device | |
202 | * | |
203 | * This function uses the read-modify-write sequence to set the direction of | |
204 | * the gpio pin as input. | |
205 | * | |
206 | * Return: 0 always | |
207 | */ | |
208 | static int zynq_gpio_dir_in(struct gpio_chip *chip, unsigned int pin) | |
209 | { | |
210 | u32 reg; | |
211 | unsigned int bank_num, bank_pin_num; | |
212 | struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip); | |
213 | ||
214 | zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num); | |
215 | ||
216 | /* bank 0 pins 7 and 8 are special and cannot be used as inputs */ | |
217 | if (bank_num == 0 && (bank_pin_num == 7 || bank_pin_num == 8)) | |
218 | return -EINVAL; | |
219 | ||
220 | /* clear the bit in direction mode reg to set the pin as input */ | |
221 | reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); | |
222 | reg &= ~BIT(bank_pin_num); | |
223 | writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); | |
224 | ||
225 | return 0; | |
226 | } | |
227 | ||
228 | /** | |
229 | * zynq_gpio_dir_out - Set the direction of the specified GPIO pin as output | |
230 | * @chip: gpio_chip instance to be worked on | |
231 | * @pin: gpio pin number within the device | |
232 | * @state: value to be written to specified pin | |
233 | * | |
234 | * This function sets the direction of specified GPIO pin as output, configures | |
235 | * the Output Enable register for the pin and uses zynq_gpio_set to set | |
236 | * the state of the pin to the value specified. | |
237 | * | |
238 | * Return: 0 always | |
239 | */ | |
240 | static int zynq_gpio_dir_out(struct gpio_chip *chip, unsigned int pin, | |
241 | int state) | |
242 | { | |
243 | u32 reg; | |
244 | unsigned int bank_num, bank_pin_num; | |
245 | struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip); | |
246 | ||
247 | zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num); | |
248 | ||
249 | /* set the GPIO pin as output */ | |
250 | reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); | |
251 | reg |= BIT(bank_pin_num); | |
252 | writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); | |
253 | ||
254 | /* configure the output enable reg for the pin */ | |
255 | reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num)); | |
256 | reg |= BIT(bank_pin_num); | |
257 | writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num)); | |
258 | ||
259 | /* set the state of the pin */ | |
260 | zynq_gpio_set_value(chip, pin, state); | |
261 | return 0; | |
262 | } | |
263 | ||
264 | /** | |
265 | * zynq_gpio_irq_mask - Disable the interrupts for a gpio pin | |
266 | * @irq_data: per irq and chip data passed down to chip functions | |
267 | * | |
268 | * This function calculates gpio pin number from irq number and sets the | |
269 | * bit in the Interrupt Disable register of the corresponding bank to disable | |
270 | * interrupts for that pin. | |
271 | */ | |
272 | static void zynq_gpio_irq_mask(struct irq_data *irq_data) | |
273 | { | |
274 | unsigned int device_pin_num, bank_num, bank_pin_num; | |
275 | struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data); | |
276 | ||
277 | device_pin_num = irq_data->hwirq; | |
278 | zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num); | |
279 | writel_relaxed(BIT(bank_pin_num), | |
280 | gpio->base_addr + ZYNQ_GPIO_INTDIS_OFFSET(bank_num)); | |
281 | } | |
282 | ||
283 | /** | |
284 | * zynq_gpio_irq_unmask - Enable the interrupts for a gpio pin | |
285 | * @irq_data: irq data containing irq number of gpio pin for the interrupt | |
286 | * to enable | |
287 | * | |
288 | * This function calculates the gpio pin number from irq number and sets the | |
289 | * bit in the Interrupt Enable register of the corresponding bank to enable | |
290 | * interrupts for that pin. | |
291 | */ | |
292 | static void zynq_gpio_irq_unmask(struct irq_data *irq_data) | |
293 | { | |
294 | unsigned int device_pin_num, bank_num, bank_pin_num; | |
295 | struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data); | |
296 | ||
297 | device_pin_num = irq_data->hwirq; | |
298 | zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num); | |
299 | writel_relaxed(BIT(bank_pin_num), | |
300 | gpio->base_addr + ZYNQ_GPIO_INTEN_OFFSET(bank_num)); | |
301 | } | |
302 | ||
190dc2e6 LPC |
303 | /** |
304 | * zynq_gpio_irq_ack - Acknowledge the interrupt of a gpio pin | |
305 | * @irq_data: irq data containing irq number of gpio pin for the interrupt | |
306 | * to ack | |
307 | * | |
308 | * This function calculates gpio pin number from irq number and sets the bit | |
309 | * in the Interrupt Status Register of the corresponding bank, to ACK the irq. | |
310 | */ | |
311 | static void zynq_gpio_irq_ack(struct irq_data *irq_data) | |
312 | { | |
313 | unsigned int device_pin_num, bank_num, bank_pin_num; | |
314 | struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data); | |
315 | ||
316 | device_pin_num = irq_data->hwirq; | |
317 | zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num); | |
318 | writel_relaxed(BIT(bank_pin_num), | |
319 | gpio->base_addr + ZYNQ_GPIO_INTSTS_OFFSET(bank_num)); | |
320 | } | |
321 | ||
322 | /** | |
323 | * zynq_gpio_irq_enable - Enable the interrupts for a gpio pin | |
324 | * @irq_data: irq data containing irq number of gpio pin for the interrupt | |
325 | * to enable | |
326 | * | |
327 | * Clears the INTSTS bit and unmasks the given interrrupt. | |
328 | */ | |
329 | static void zynq_gpio_irq_enable(struct irq_data *irq_data) | |
330 | { | |
331 | /* | |
332 | * The Zynq GPIO controller does not disable interrupt detection when | |
333 | * the interrupt is masked and only disables the propagation of the | |
334 | * interrupt. This means when the controller detects an interrupt | |
335 | * condition while the interrupt is logically disabled it will propagate | |
336 | * that interrupt event once the interrupt is enabled. This will cause | |
337 | * the interrupt consumer to see spurious interrupts to prevent this | |
338 | * first make sure that the interrupt is not asserted and then enable | |
339 | * it. | |
340 | */ | |
341 | zynq_gpio_irq_ack(irq_data); | |
342 | zynq_gpio_irq_unmask(irq_data); | |
343 | } | |
344 | ||
3242ba11 HK |
345 | /** |
346 | * zynq_gpio_set_irq_type - Set the irq type for a gpio pin | |
347 | * @irq_data: irq data containing irq number of gpio pin | |
348 | * @type: interrupt type that is to be set for the gpio pin | |
349 | * | |
350 | * This function gets the gpio pin number and its bank from the gpio pin number | |
351 | * and configures the INT_TYPE, INT_POLARITY and INT_ANY registers. | |
352 | * | |
353 | * Return: 0, negative error otherwise. | |
354 | * TYPE-EDGE_RISING, INT_TYPE - 1, INT_POLARITY - 1, INT_ANY - 0; | |
355 | * TYPE-EDGE_FALLING, INT_TYPE - 1, INT_POLARITY - 0, INT_ANY - 0; | |
356 | * TYPE-EDGE_BOTH, INT_TYPE - 1, INT_POLARITY - NA, INT_ANY - 1; | |
357 | * TYPE-LEVEL_HIGH, INT_TYPE - 0, INT_POLARITY - 1, INT_ANY - NA; | |
358 | * TYPE-LEVEL_LOW, INT_TYPE - 0, INT_POLARITY - 0, INT_ANY - NA | |
359 | */ | |
360 | static int zynq_gpio_set_irq_type(struct irq_data *irq_data, unsigned int type) | |
361 | { | |
362 | u32 int_type, int_pol, int_any; | |
363 | unsigned int device_pin_num, bank_num, bank_pin_num; | |
364 | struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data); | |
365 | ||
366 | device_pin_num = irq_data->hwirq; | |
367 | zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num); | |
368 | ||
369 | int_type = readl_relaxed(gpio->base_addr + | |
370 | ZYNQ_GPIO_INTTYPE_OFFSET(bank_num)); | |
371 | int_pol = readl_relaxed(gpio->base_addr + | |
372 | ZYNQ_GPIO_INTPOL_OFFSET(bank_num)); | |
373 | int_any = readl_relaxed(gpio->base_addr + | |
374 | ZYNQ_GPIO_INTANY_OFFSET(bank_num)); | |
375 | ||
376 | /* | |
377 | * based on the type requested, configure the INT_TYPE, INT_POLARITY | |
378 | * and INT_ANY registers | |
379 | */ | |
380 | switch (type) { | |
381 | case IRQ_TYPE_EDGE_RISING: | |
382 | int_type |= BIT(bank_pin_num); | |
383 | int_pol |= BIT(bank_pin_num); | |
384 | int_any &= ~BIT(bank_pin_num); | |
385 | break; | |
386 | case IRQ_TYPE_EDGE_FALLING: | |
387 | int_type |= BIT(bank_pin_num); | |
388 | int_pol &= ~BIT(bank_pin_num); | |
389 | int_any &= ~BIT(bank_pin_num); | |
390 | break; | |
391 | case IRQ_TYPE_EDGE_BOTH: | |
392 | int_type |= BIT(bank_pin_num); | |
393 | int_any |= BIT(bank_pin_num); | |
394 | break; | |
395 | case IRQ_TYPE_LEVEL_HIGH: | |
396 | int_type &= ~BIT(bank_pin_num); | |
397 | int_pol |= BIT(bank_pin_num); | |
398 | break; | |
399 | case IRQ_TYPE_LEVEL_LOW: | |
400 | int_type &= ~BIT(bank_pin_num); | |
401 | int_pol &= ~BIT(bank_pin_num); | |
402 | break; | |
403 | default: | |
404 | return -EINVAL; | |
405 | } | |
406 | ||
407 | writel_relaxed(int_type, | |
408 | gpio->base_addr + ZYNQ_GPIO_INTTYPE_OFFSET(bank_num)); | |
409 | writel_relaxed(int_pol, | |
410 | gpio->base_addr + ZYNQ_GPIO_INTPOL_OFFSET(bank_num)); | |
411 | writel_relaxed(int_any, | |
412 | gpio->base_addr + ZYNQ_GPIO_INTANY_OFFSET(bank_num)); | |
413 | return 0; | |
414 | } | |
415 | ||
416 | static int zynq_gpio_set_wake(struct irq_data *data, unsigned int on) | |
417 | { | |
418 | if (on) | |
419 | zynq_gpio_irq_unmask(data); | |
420 | else | |
421 | zynq_gpio_irq_mask(data); | |
422 | ||
423 | return 0; | |
424 | } | |
425 | ||
426 | /* irq chip descriptor */ | |
427 | static struct irq_chip zynq_gpio_irqchip = { | |
428 | .name = DRIVER_NAME, | |
190dc2e6 | 429 | .irq_enable = zynq_gpio_irq_enable, |
3242ba11 HK |
430 | .irq_mask = zynq_gpio_irq_mask, |
431 | .irq_unmask = zynq_gpio_irq_unmask, | |
432 | .irq_set_type = zynq_gpio_set_irq_type, | |
433 | .irq_set_wake = zynq_gpio_set_wake, | |
434 | }; | |
435 | ||
436 | /** | |
437 | * zynq_gpio_irqhandler - IRQ handler for the gpio banks of a gpio device | |
438 | * @irq: irq number of the gpio bank where interrupt has occurred | |
439 | * @desc: irq descriptor instance of the 'irq' | |
440 | * | |
441 | * This function reads the Interrupt Status Register of each bank to get the | |
442 | * gpio pin number which has triggered an interrupt. It then acks the triggered | |
443 | * interrupt and calls the pin specific handler set by the higher layer | |
444 | * application for that pin. | |
445 | * Note: A bug is reported if no handler is set for the gpio pin. | |
446 | */ | |
447 | static void zynq_gpio_irqhandler(unsigned int irq, struct irq_desc *desc) | |
448 | { | |
449 | u32 int_sts, int_enb; | |
450 | unsigned int bank_num; | |
451 | struct zynq_gpio *gpio = irq_get_handler_data(irq); | |
452 | struct irq_chip *irqchip = irq_desc_get_chip(desc); | |
453 | ||
454 | chained_irq_enter(irqchip, desc); | |
455 | ||
456 | for (bank_num = 0; bank_num < ZYNQ_GPIO_MAX_BANK; bank_num++) { | |
457 | int_sts = readl_relaxed(gpio->base_addr + | |
458 | ZYNQ_GPIO_INTSTS_OFFSET(bank_num)); | |
459 | int_enb = readl_relaxed(gpio->base_addr + | |
460 | ZYNQ_GPIO_INTMASK_OFFSET(bank_num)); | |
461 | int_sts &= ~int_enb; | |
462 | if (int_sts) { | |
463 | int offset; | |
464 | unsigned long pending = int_sts; | |
465 | ||
466 | for_each_set_bit(offset, &pending, 32) { | |
467 | unsigned int gpio_irq = | |
468 | irq_find_mapping(gpio->chip.irqdomain, | |
469 | offset); | |
470 | generic_handle_irq(gpio_irq); | |
471 | } | |
472 | ||
473 | /* clear IRQ in HW */ | |
474 | writel_relaxed(int_sts, gpio->base_addr + | |
475 | ZYNQ_GPIO_INTSTS_OFFSET(bank_num)); | |
476 | } | |
477 | } | |
478 | ||
479 | chained_irq_exit(irqchip, desc); | |
480 | } | |
481 | ||
482 | static int __maybe_unused zynq_gpio_suspend(struct device *dev) | |
483 | { | |
484 | if (!device_may_wakeup(dev)) | |
485 | return pm_runtime_force_suspend(dev); | |
486 | ||
487 | return 0; | |
488 | } | |
489 | ||
490 | static int __maybe_unused zynq_gpio_resume(struct device *dev) | |
491 | { | |
492 | if (!device_may_wakeup(dev)) | |
493 | return pm_runtime_force_resume(dev); | |
494 | ||
495 | return 0; | |
496 | } | |
497 | ||
498 | static int __maybe_unused zynq_gpio_runtime_suspend(struct device *dev) | |
499 | { | |
500 | struct platform_device *pdev = to_platform_device(dev); | |
501 | struct zynq_gpio *gpio = platform_get_drvdata(pdev); | |
502 | ||
503 | clk_disable_unprepare(gpio->clk); | |
504 | ||
505 | return 0; | |
506 | } | |
507 | ||
508 | static int __maybe_unused zynq_gpio_runtime_resume(struct device *dev) | |
509 | { | |
510 | struct platform_device *pdev = to_platform_device(dev); | |
511 | struct zynq_gpio *gpio = platform_get_drvdata(pdev); | |
512 | ||
513 | return clk_prepare_enable(gpio->clk); | |
514 | } | |
515 | ||
516 | static int zynq_gpio_request(struct gpio_chip *chip, unsigned offset) | |
517 | { | |
518 | int ret; | |
519 | ||
520 | ret = pm_runtime_get_sync(chip->dev); | |
521 | ||
522 | /* | |
523 | * If the device is already active pm_runtime_get() will return 1 on | |
524 | * success, but gpio_request still needs to return 0. | |
525 | */ | |
526 | return ret < 0 ? ret : 0; | |
527 | } | |
528 | ||
529 | static void zynq_gpio_free(struct gpio_chip *chip, unsigned offset) | |
530 | { | |
531 | pm_runtime_put(chip->dev); | |
532 | } | |
533 | ||
534 | static const struct dev_pm_ops zynq_gpio_dev_pm_ops = { | |
535 | SET_SYSTEM_SLEEP_PM_OPS(zynq_gpio_suspend, zynq_gpio_resume) | |
536 | SET_PM_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend, | |
537 | zynq_gpio_runtime_resume, NULL) | |
538 | }; | |
539 | ||
540 | /** | |
541 | * zynq_gpio_probe - Initialization method for a zynq_gpio device | |
542 | * @pdev: platform device instance | |
543 | * | |
544 | * This function allocates memory resources for the gpio device and registers | |
545 | * all the banks of the device. It will also set up interrupts for the gpio | |
546 | * pins. | |
547 | * Note: Interrupts are disabled for all the banks during initialization. | |
548 | * | |
549 | * Return: 0 on success, negative error otherwise. | |
550 | */ | |
551 | static int zynq_gpio_probe(struct platform_device *pdev) | |
552 | { | |
553 | int ret, bank_num, irq; | |
554 | struct zynq_gpio *gpio; | |
555 | struct gpio_chip *chip; | |
556 | struct resource *res; | |
557 | ||
558 | gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); | |
559 | if (!gpio) | |
560 | return -ENOMEM; | |
561 | ||
562 | platform_set_drvdata(pdev, gpio); | |
563 | ||
564 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
565 | gpio->base_addr = devm_ioremap_resource(&pdev->dev, res); | |
566 | if (IS_ERR(gpio->base_addr)) | |
567 | return PTR_ERR(gpio->base_addr); | |
568 | ||
569 | irq = platform_get_irq(pdev, 0); | |
570 | if (irq < 0) { | |
571 | dev_err(&pdev->dev, "invalid IRQ\n"); | |
572 | return irq; | |
573 | } | |
574 | ||
575 | /* configure the gpio chip */ | |
576 | chip = &gpio->chip; | |
577 | chip->label = "zynq_gpio"; | |
578 | chip->owner = THIS_MODULE; | |
579 | chip->dev = &pdev->dev; | |
580 | chip->get = zynq_gpio_get_value; | |
581 | chip->set = zynq_gpio_set_value; | |
582 | chip->request = zynq_gpio_request; | |
583 | chip->free = zynq_gpio_free; | |
584 | chip->direction_input = zynq_gpio_dir_in; | |
585 | chip->direction_output = zynq_gpio_dir_out; | |
586 | chip->base = -1; | |
587 | chip->ngpio = ZYNQ_GPIO_NR_GPIOS; | |
588 | ||
589 | /* Enable GPIO clock */ | |
590 | gpio->clk = devm_clk_get(&pdev->dev, NULL); | |
591 | if (IS_ERR(gpio->clk)) { | |
592 | dev_err(&pdev->dev, "input clock not found.\n"); | |
593 | return PTR_ERR(gpio->clk); | |
594 | } | |
595 | ret = clk_prepare_enable(gpio->clk); | |
596 | if (ret) { | |
597 | dev_err(&pdev->dev, "Unable to enable clock.\n"); | |
598 | return ret; | |
599 | } | |
600 | ||
601 | /* report a bug if gpio chip registration fails */ | |
602 | ret = gpiochip_add(chip); | |
603 | if (ret) { | |
604 | dev_err(&pdev->dev, "Failed to add gpio chip\n"); | |
605 | goto err_disable_clk; | |
606 | } | |
607 | ||
608 | /* disable interrupts for all banks */ | |
609 | for (bank_num = 0; bank_num < ZYNQ_GPIO_MAX_BANK; bank_num++) | |
610 | writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr + | |
611 | ZYNQ_GPIO_INTDIS_OFFSET(bank_num)); | |
612 | ||
613 | ret = gpiochip_irqchip_add(chip, &zynq_gpio_irqchip, 0, | |
614 | handle_simple_irq, IRQ_TYPE_NONE); | |
615 | if (ret) { | |
616 | dev_err(&pdev->dev, "Failed to add irq chip\n"); | |
617 | goto err_rm_gpiochip; | |
618 | } | |
619 | ||
620 | gpiochip_set_chained_irqchip(chip, &zynq_gpio_irqchip, irq, | |
621 | zynq_gpio_irqhandler); | |
622 | ||
623 | pm_runtime_set_active(&pdev->dev); | |
624 | pm_runtime_enable(&pdev->dev); | |
625 | ||
626 | device_set_wakeup_capable(&pdev->dev, 1); | |
627 | ||
628 | return 0; | |
629 | ||
630 | err_rm_gpiochip: | |
631 | if (gpiochip_remove(chip)) | |
632 | dev_err(&pdev->dev, "Failed to remove gpio chip\n"); | |
633 | err_disable_clk: | |
634 | clk_disable_unprepare(gpio->clk); | |
635 | ||
636 | return ret; | |
637 | } | |
638 | ||
639 | /** | |
640 | * zynq_gpio_remove - Driver removal function | |
641 | * @pdev: platform device instance | |
642 | * | |
643 | * Return: 0 always | |
644 | */ | |
645 | static int zynq_gpio_remove(struct platform_device *pdev) | |
646 | { | |
647 | int ret; | |
648 | struct zynq_gpio *gpio = platform_get_drvdata(pdev); | |
649 | ||
650 | pm_runtime_get_sync(&pdev->dev); | |
651 | ||
652 | ret = gpiochip_remove(&gpio->chip); | |
653 | if (ret) { | |
654 | dev_err(&pdev->dev, "Failed to remove gpio chip\n"); | |
655 | return ret; | |
656 | } | |
657 | clk_disable_unprepare(gpio->clk); | |
658 | device_set_wakeup_capable(&pdev->dev, 0); | |
659 | return 0; | |
660 | } | |
661 | ||
662 | static struct of_device_id zynq_gpio_of_match[] = { | |
663 | { .compatible = "xlnx,zynq-gpio-1.0", }, | |
664 | { /* end of table */ } | |
665 | }; | |
666 | MODULE_DEVICE_TABLE(of, zynq_gpio_of_match); | |
667 | ||
668 | static struct platform_driver zynq_gpio_driver = { | |
669 | .driver = { | |
670 | .name = DRIVER_NAME, | |
671 | .owner = THIS_MODULE, | |
672 | .pm = &zynq_gpio_dev_pm_ops, | |
673 | .of_match_table = zynq_gpio_of_match, | |
674 | }, | |
675 | .probe = zynq_gpio_probe, | |
676 | .remove = zynq_gpio_remove, | |
677 | }; | |
678 | ||
679 | /** | |
680 | * zynq_gpio_init - Initial driver registration call | |
681 | * | |
682 | * Return: value from platform_driver_register | |
683 | */ | |
684 | static int __init zynq_gpio_init(void) | |
685 | { | |
686 | return platform_driver_register(&zynq_gpio_driver); | |
687 | } | |
688 | postcore_initcall(zynq_gpio_init); | |
689 | ||
690 | MODULE_AUTHOR("Xilinx Inc."); | |
691 | MODULE_DESCRIPTION("Zynq GPIO driver"); | |
692 | MODULE_LICENSE("GPL"); |