Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
49cec4d8 | 2 | /* |
9d3a15aa | 3 | * Faraday Technolog FTGPIO010 gpiochip and interrupt routines |
49cec4d8 LW |
4 | * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> |
5 | * | |
6 | * Based on arch/arm/mach-gemini/gpio.c: | |
7 | * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt> | |
8 | * | |
9 | * Based on plat-mxc/gpio.c: | |
10 | * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> | |
11 | * Copyright 2008 Juergen Beisert, kernel@pengutronix.de | |
12 | */ | |
13 | #include <linux/gpio/driver.h> | |
14 | #include <linux/io.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <linux/platform_device.h> | |
49cec4d8 | 17 | #include <linux/bitops.h> |
da02d794 | 18 | #include <linux/clk.h> |
49cec4d8 LW |
19 | |
20 | /* GPIO registers definition */ | |
21 | #define GPIO_DATA_OUT 0x00 | |
22 | #define GPIO_DATA_IN 0x04 | |
23 | #define GPIO_DIR 0x08 | |
69a87f29 | 24 | #define GPIO_BYPASS_IN 0x0C |
49cec4d8 LW |
25 | #define GPIO_DATA_SET 0x10 |
26 | #define GPIO_DATA_CLR 0x14 | |
27 | #define GPIO_PULL_EN 0x18 | |
28 | #define GPIO_PULL_TYPE 0x1C | |
29 | #define GPIO_INT_EN 0x20 | |
69a87f29 LW |
30 | #define GPIO_INT_STAT_RAW 0x24 |
31 | #define GPIO_INT_STAT_MASKED 0x28 | |
49cec4d8 LW |
32 | #define GPIO_INT_MASK 0x2C |
33 | #define GPIO_INT_CLR 0x30 | |
34 | #define GPIO_INT_TYPE 0x34 | |
35 | #define GPIO_INT_BOTH_EDGE 0x38 | |
36 | #define GPIO_INT_LEVEL 0x3C | |
37 | #define GPIO_DEBOUNCE_EN 0x40 | |
38 | #define GPIO_DEBOUNCE_PRESCALE 0x44 | |
39 | ||
40 | /** | |
9d3a15aa | 41 | * struct ftgpio_gpio - Gemini GPIO state container |
49cec4d8 LW |
42 | * @dev: containing device for this instance |
43 | * @gc: gpiochip for this instance | |
da02d794 LW |
44 | * @base: remapped I/O-memory base |
45 | * @clk: silicon clock | |
49cec4d8 | 46 | */ |
9d3a15aa | 47 | struct ftgpio_gpio { |
49cec4d8 LW |
48 | struct device *dev; |
49 | struct gpio_chip gc; | |
50 | void __iomem *base; | |
da02d794 | 51 | struct clk *clk; |
49cec4d8 LW |
52 | }; |
53 | ||
9d3a15aa | 54 | static void ftgpio_gpio_ack_irq(struct irq_data *d) |
49cec4d8 LW |
55 | { |
56 | struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | |
9d3a15aa | 57 | struct ftgpio_gpio *g = gpiochip_get_data(gc); |
49cec4d8 LW |
58 | |
59 | writel(BIT(irqd_to_hwirq(d)), g->base + GPIO_INT_CLR); | |
60 | } | |
61 | ||
9d3a15aa | 62 | static void ftgpio_gpio_mask_irq(struct irq_data *d) |
49cec4d8 LW |
63 | { |
64 | struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | |
9d3a15aa | 65 | struct ftgpio_gpio *g = gpiochip_get_data(gc); |
49cec4d8 LW |
66 | u32 val; |
67 | ||
68 | val = readl(g->base + GPIO_INT_EN); | |
69 | val &= ~BIT(irqd_to_hwirq(d)); | |
70 | writel(val, g->base + GPIO_INT_EN); | |
71 | } | |
72 | ||
9d3a15aa | 73 | static void ftgpio_gpio_unmask_irq(struct irq_data *d) |
49cec4d8 LW |
74 | { |
75 | struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | |
9d3a15aa | 76 | struct ftgpio_gpio *g = gpiochip_get_data(gc); |
49cec4d8 LW |
77 | u32 val; |
78 | ||
79 | val = readl(g->base + GPIO_INT_EN); | |
80 | val |= BIT(irqd_to_hwirq(d)); | |
81 | writel(val, g->base + GPIO_INT_EN); | |
82 | } | |
83 | ||
9d3a15aa | 84 | static int ftgpio_gpio_set_irq_type(struct irq_data *d, unsigned int type) |
49cec4d8 LW |
85 | { |
86 | struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | |
9d3a15aa | 87 | struct ftgpio_gpio *g = gpiochip_get_data(gc); |
49cec4d8 LW |
88 | u32 mask = BIT(irqd_to_hwirq(d)); |
89 | u32 reg_both, reg_level, reg_type; | |
90 | ||
91 | reg_type = readl(g->base + GPIO_INT_TYPE); | |
92 | reg_level = readl(g->base + GPIO_INT_LEVEL); | |
93 | reg_both = readl(g->base + GPIO_INT_BOTH_EDGE); | |
94 | ||
95 | switch (type) { | |
96 | case IRQ_TYPE_EDGE_BOTH: | |
97 | irq_set_handler_locked(d, handle_edge_irq); | |
98 | reg_type &= ~mask; | |
99 | reg_both |= mask; | |
100 | break; | |
101 | case IRQ_TYPE_EDGE_RISING: | |
102 | irq_set_handler_locked(d, handle_edge_irq); | |
103 | reg_type &= ~mask; | |
104 | reg_both &= ~mask; | |
105 | reg_level &= ~mask; | |
106 | break; | |
107 | case IRQ_TYPE_EDGE_FALLING: | |
108 | irq_set_handler_locked(d, handle_edge_irq); | |
109 | reg_type &= ~mask; | |
110 | reg_both &= ~mask; | |
111 | reg_level |= mask; | |
112 | break; | |
113 | case IRQ_TYPE_LEVEL_HIGH: | |
114 | irq_set_handler_locked(d, handle_level_irq); | |
115 | reg_type |= mask; | |
116 | reg_level &= ~mask; | |
117 | break; | |
118 | case IRQ_TYPE_LEVEL_LOW: | |
119 | irq_set_handler_locked(d, handle_level_irq); | |
120 | reg_type |= mask; | |
121 | reg_level |= mask; | |
122 | break; | |
123 | default: | |
124 | irq_set_handler_locked(d, handle_bad_irq); | |
125 | return -EINVAL; | |
126 | } | |
127 | ||
128 | writel(reg_type, g->base + GPIO_INT_TYPE); | |
129 | writel(reg_level, g->base + GPIO_INT_LEVEL); | |
130 | writel(reg_both, g->base + GPIO_INT_BOTH_EDGE); | |
131 | ||
9d3a15aa | 132 | ftgpio_gpio_ack_irq(d); |
49cec4d8 LW |
133 | |
134 | return 0; | |
135 | } | |
136 | ||
9d3a15aa LW |
137 | static struct irq_chip ftgpio_gpio_irqchip = { |
138 | .name = "FTGPIO010", | |
139 | .irq_ack = ftgpio_gpio_ack_irq, | |
140 | .irq_mask = ftgpio_gpio_mask_irq, | |
141 | .irq_unmask = ftgpio_gpio_unmask_irq, | |
142 | .irq_set_type = ftgpio_gpio_set_irq_type, | |
49cec4d8 LW |
143 | }; |
144 | ||
9d3a15aa | 145 | static void ftgpio_gpio_irq_handler(struct irq_desc *desc) |
49cec4d8 LW |
146 | { |
147 | struct gpio_chip *gc = irq_desc_get_handler_data(desc); | |
9d3a15aa | 148 | struct ftgpio_gpio *g = gpiochip_get_data(gc); |
49cec4d8 LW |
149 | struct irq_chip *irqchip = irq_desc_get_chip(desc); |
150 | int offset; | |
151 | unsigned long stat; | |
152 | ||
153 | chained_irq_enter(irqchip, desc); | |
154 | ||
69a87f29 | 155 | stat = readl(g->base + GPIO_INT_STAT_RAW); |
49cec4d8 LW |
156 | if (stat) |
157 | for_each_set_bit(offset, &stat, gc->ngpio) | |
f0fbe7bc | 158 | generic_handle_irq(irq_find_mapping(gc->irq.domain, |
49cec4d8 LW |
159 | offset)); |
160 | ||
161 | chained_irq_exit(irqchip, desc); | |
162 | } | |
163 | ||
36f3f19a LW |
164 | static int ftgpio_gpio_set_config(struct gpio_chip *gc, unsigned int offset, |
165 | unsigned long config) | |
166 | { | |
167 | enum pin_config_param param = pinconf_to_config_param(config); | |
168 | u32 arg = pinconf_to_config_argument(config); | |
169 | struct ftgpio_gpio *g = gpiochip_get_data(gc); | |
170 | unsigned long pclk_freq; | |
171 | u32 deb_div; | |
172 | u32 val; | |
173 | ||
174 | if (param != PIN_CONFIG_INPUT_DEBOUNCE) | |
175 | return -ENOTSUPP; | |
176 | ||
177 | /* | |
178 | * Debounce only works if interrupts are enabled. The manual | |
179 | * states that if PCLK is 66 MHz, and this is set to 0x7D0, then | |
180 | * PCLK is divided down to 33 kHz for the debounce timer. 0x7D0 is | |
181 | * 2000 decimal, so what they mean is simply that the PCLK is | |
182 | * divided by this value. | |
183 | * | |
184 | * As we get a debounce setting in microseconds, we calculate the | |
185 | * desired period time and see if we can get a suitable debounce | |
186 | * time. | |
187 | */ | |
188 | pclk_freq = clk_get_rate(g->clk); | |
189 | deb_div = DIV_ROUND_CLOSEST(pclk_freq, arg); | |
190 | ||
191 | /* This register is only 24 bits wide */ | |
192 | if (deb_div > (1 << 24)) | |
193 | return -ENOTSUPP; | |
194 | ||
195 | dev_dbg(g->dev, "prescale divisor: %08x, resulting frequency %lu Hz\n", | |
196 | deb_div, (pclk_freq/deb_div)); | |
197 | ||
198 | val = readl(g->base + GPIO_DEBOUNCE_PRESCALE); | |
199 | if (val == deb_div) { | |
200 | /* | |
201 | * The debounce timer happens to already be set to the | |
202 | * desireable value, what a coincidence! We can just enable | |
203 | * debounce on this GPIO line and return. This happens more | |
204 | * often than you think, for example when all GPIO keys | |
205 | * on a system are requesting the same debounce interval. | |
206 | */ | |
207 | val = readl(g->base + GPIO_DEBOUNCE_EN); | |
208 | val |= BIT(offset); | |
209 | writel(val, g->base + GPIO_DEBOUNCE_EN); | |
210 | return 0; | |
211 | } | |
212 | ||
213 | val = readl(g->base + GPIO_DEBOUNCE_EN); | |
214 | if (val) { | |
215 | /* | |
216 | * Oh no! Someone is already using the debounce with | |
217 | * another setting than what we need. Bummer. | |
218 | */ | |
219 | return -ENOTSUPP; | |
220 | } | |
221 | ||
222 | /* First come, first serve */ | |
223 | writel(deb_div, g->base + GPIO_DEBOUNCE_PRESCALE); | |
224 | /* Enable debounce */ | |
225 | val |= BIT(offset); | |
226 | writel(val, g->base + GPIO_DEBOUNCE_EN); | |
227 | ||
228 | return 0; | |
229 | } | |
230 | ||
9d3a15aa | 231 | static int ftgpio_gpio_probe(struct platform_device *pdev) |
49cec4d8 LW |
232 | { |
233 | struct device *dev = &pdev->dev; | |
234 | struct resource *res; | |
9d3a15aa | 235 | struct ftgpio_gpio *g; |
49cec4d8 LW |
236 | int irq; |
237 | int ret; | |
238 | ||
239 | g = devm_kzalloc(dev, sizeof(*g), GFP_KERNEL); | |
240 | if (!g) | |
241 | return -ENOMEM; | |
242 | ||
243 | g->dev = dev; | |
244 | ||
245 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
246 | g->base = devm_ioremap_resource(dev, res); | |
247 | if (IS_ERR(g->base)) | |
248 | return PTR_ERR(g->base); | |
249 | ||
250 | irq = platform_get_irq(pdev, 0); | |
4070a534 AY |
251 | if (irq <= 0) |
252 | return irq ? irq : -EINVAL; | |
49cec4d8 | 253 | |
da02d794 LW |
254 | g->clk = devm_clk_get(dev, NULL); |
255 | if (!IS_ERR(g->clk)) { | |
256 | ret = clk_prepare_enable(g->clk); | |
257 | if (ret) | |
258 | return ret; | |
259 | } else if (PTR_ERR(g->clk) == -EPROBE_DEFER) { | |
260 | /* | |
261 | * Percolate deferrals, for anything else, | |
262 | * just live without the clocking. | |
263 | */ | |
264 | return PTR_ERR(g->clk); | |
265 | } | |
266 | ||
49cec4d8 LW |
267 | ret = bgpio_init(&g->gc, dev, 4, |
268 | g->base + GPIO_DATA_IN, | |
269 | g->base + GPIO_DATA_SET, | |
270 | g->base + GPIO_DATA_CLR, | |
271 | g->base + GPIO_DIR, | |
272 | NULL, | |
273 | 0); | |
274 | if (ret) { | |
275 | dev_err(dev, "unable to init generic GPIO\n"); | |
da02d794 | 276 | goto dis_clk; |
49cec4d8 | 277 | } |
9d3a15aa | 278 | g->gc.label = "FTGPIO010"; |
49cec4d8 LW |
279 | g->gc.base = -1; |
280 | g->gc.parent = dev; | |
281 | g->gc.owner = THIS_MODULE; | |
282 | /* ngpio is set by bgpio_init() */ | |
283 | ||
36f3f19a LW |
284 | /* We need a silicon clock to do debounce */ |
285 | if (!IS_ERR(g->clk)) | |
286 | g->gc.set_config = ftgpio_gpio_set_config; | |
287 | ||
49cec4d8 LW |
288 | ret = devm_gpiochip_add_data(dev, &g->gc, g); |
289 | if (ret) | |
da02d794 | 290 | goto dis_clk; |
49cec4d8 LW |
291 | |
292 | /* Disable, unmask and clear all interrupts */ | |
293 | writel(0x0, g->base + GPIO_INT_EN); | |
294 | writel(0x0, g->base + GPIO_INT_MASK); | |
295 | writel(~0x0, g->base + GPIO_INT_CLR); | |
296 | ||
36f3f19a LW |
297 | /* Clear any use of debounce */ |
298 | writel(0x0, g->base + GPIO_DEBOUNCE_EN); | |
299 | ||
9d3a15aa | 300 | ret = gpiochip_irqchip_add(&g->gc, &ftgpio_gpio_irqchip, |
49cec4d8 LW |
301 | 0, handle_bad_irq, |
302 | IRQ_TYPE_NONE); | |
303 | if (ret) { | |
304 | dev_info(dev, "could not add irqchip\n"); | |
da02d794 | 305 | goto dis_clk; |
49cec4d8 | 306 | } |
9d3a15aa LW |
307 | gpiochip_set_chained_irqchip(&g->gc, &ftgpio_gpio_irqchip, |
308 | irq, ftgpio_gpio_irq_handler); | |
49cec4d8 | 309 | |
da02d794 | 310 | platform_set_drvdata(pdev, g); |
9d3a15aa | 311 | dev_info(dev, "FTGPIO010 @%p registered\n", g->base); |
49cec4d8 LW |
312 | |
313 | return 0; | |
da02d794 LW |
314 | |
315 | dis_clk: | |
316 | if (!IS_ERR(g->clk)) | |
317 | clk_disable_unprepare(g->clk); | |
318 | return ret; | |
319 | } | |
320 | ||
321 | static int ftgpio_gpio_remove(struct platform_device *pdev) | |
322 | { | |
323 | struct ftgpio_gpio *g = platform_get_drvdata(pdev); | |
324 | ||
325 | if (!IS_ERR(g->clk)) | |
326 | clk_disable_unprepare(g->clk); | |
327 | return 0; | |
49cec4d8 LW |
328 | } |
329 | ||
9d3a15aa | 330 | static const struct of_device_id ftgpio_gpio_of_match[] = { |
49cec4d8 LW |
331 | { |
332 | .compatible = "cortina,gemini-gpio", | |
333 | }, | |
9d3a15aa LW |
334 | { |
335 | .compatible = "moxa,moxart-gpio", | |
336 | }, | |
337 | { | |
338 | .compatible = "faraday,ftgpio010", | |
339 | }, | |
49cec4d8 LW |
340 | {}, |
341 | }; | |
342 | ||
9d3a15aa | 343 | static struct platform_driver ftgpio_gpio_driver = { |
49cec4d8 | 344 | .driver = { |
9d3a15aa LW |
345 | .name = "ftgpio010-gpio", |
346 | .of_match_table = of_match_ptr(ftgpio_gpio_of_match), | |
49cec4d8 | 347 | }, |
da02d794 LW |
348 | .probe = ftgpio_gpio_probe, |
349 | .remove = ftgpio_gpio_remove, | |
49cec4d8 | 350 | }; |
9d3a15aa | 351 | builtin_platform_driver(ftgpio_gpio_driver); |