1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* Abilis Systems MODULE DESCRIPTION |
3 | * |
4 | * Copyright (C) Abilis Systems 2013 |
5 | * |
6 | * Authors: Sascha Leuenberger <sascha.leuenberger@abilis.com> |
7 | * Christian Ruppert <christian.ruppert@abilis.com> |
8 | */ |
9 | |
10 | #include <linux/kernel.h> |
11 | #include <linux/module.h> |
12 | #include <linux/platform_device.h> |
13 | #include <linux/gpio/driver.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/irq.h> |
16 | #include <linux/irqdomain.h> |
17 | #include <linux/interrupt.h> |
18 | #include <linux/io.h> |
19 | #include <linux/of.h> |
20 | #include <linux/of_platform.h> |
21 | #include <linux/spinlock.h> |
22 | #include <linux/bitops.h> |
23 | #include <linux/pinctrl/consumer.h> |
24 | |
25 | #define TB10X_GPIO_DIR_IN (0x00000000) |
26 | #define TB10X_GPIO_DIR_OUT (0x00000001) |
27 | #define OFFSET_TO_REG_DDR (0x00) |
28 | #define OFFSET_TO_REG_DATA (0x04) |
29 | #define OFFSET_TO_REG_INT_EN (0x08) |
30 | #define OFFSET_TO_REG_CHANGE (0x0C) |
31 | #define OFFSET_TO_REG_WRMASK (0x10) |
32 | #define OFFSET_TO_REG_INT_TYPE (0x14) |
33 | |
34 | |
35 | /** |
36 | * @base: register base address |
37 | * @domain: IRQ domain of GPIO generated interrupts managed by this controller |
38 | * @irq: Interrupt line of parent interrupt controller |
39 | * @gc: gpio_chip structure associated to this GPIO controller |
40 | */ |
41 | struct tb10x_gpio { |
42 | void __iomem *base; |
43 | struct irq_domain *domain; |
44 | int irq; |
45 | struct gpio_chip gc; |
46 | }; |
47 | |
48 | static inline u32 tb10x_reg_read(struct tb10x_gpio *gpio, unsigned int offs) |
49 | { |
50 | return ioread32(gpio->base + offs); |
51 | } |
52 | |
53 | static inline void tb10x_reg_write(struct tb10x_gpio *gpio, unsigned int offs, |
54 | u32 val) |
55 | { |
56 | iowrite32(val, gpio->base + offs); |
57 | } |
58 | |
59 | static inline void tb10x_set_bits(struct tb10x_gpio *gpio, unsigned int offs, |
60 | u32 mask, u32 val) |
61 | { |
62 | u32 r; |
63 | unsigned long flags; |
64 | |
65 | raw_spin_lock_irqsave(&gpio->gc.bgpio_lock, flags); |
66 | |
67 | r = tb10x_reg_read(gpio, offs); |
68 | r = (r & ~mask) | (val & mask); |
69 | |
70 | tb10x_reg_write(gpio, offs, val: r); |
71 | |
72 | raw_spin_unlock_irqrestore(&gpio->gc.bgpio_lock, flags); |
73 | } |
74 | |
75 | static int tb10x_gpio_to_irq(struct gpio_chip *chip, unsigned offset) |
76 | { |
77 | struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(gc: chip); |
78 | |
79 | return irq_create_mapping(host: tb10x_gpio->domain, hwirq: offset); |
80 | } |
81 | |
82 | static int tb10x_gpio_irq_set_type(struct irq_data *data, unsigned int type) |
83 | { |
84 | if ((type & IRQF_TRIGGER_MASK) != IRQ_TYPE_EDGE_BOTH) { |
85 | pr_err("Only (both) edge triggered interrupts supported.\n" ); |
86 | return -EINVAL; |
87 | } |
88 | |
89 | irqd_set_trigger_type(d: data, type); |
90 | |
91 | return IRQ_SET_MASK_OK; |
92 | } |
93 | |
94 | static irqreturn_t tb10x_gpio_irq_cascade(int irq, void *data) |
95 | { |
96 | struct tb10x_gpio *tb10x_gpio = data; |
97 | u32 r = tb10x_reg_read(gpio: tb10x_gpio, OFFSET_TO_REG_CHANGE); |
98 | u32 m = tb10x_reg_read(gpio: tb10x_gpio, OFFSET_TO_REG_INT_EN); |
99 | const unsigned long bits = r & m; |
100 | int i; |
101 | |
102 | for_each_set_bit(i, &bits, 32) |
103 | generic_handle_domain_irq(domain: tb10x_gpio->domain, hwirq: i); |
104 | |
105 | return IRQ_HANDLED; |
106 | } |
107 | |
108 | static int tb10x_gpio_probe(struct platform_device *pdev) |
109 | { |
110 | struct tb10x_gpio *tb10x_gpio; |
111 | struct device *dev = &pdev->dev; |
112 | struct device_node *np = dev->of_node; |
113 | int ret = -EBUSY; |
114 | u32 ngpio; |
115 | |
116 | if (!np) |
117 | return -EINVAL; |
118 | |
119 | if (of_property_read_u32(np, propname: "abilis,ngpio" , out_value: &ngpio)) |
120 | return -EINVAL; |
121 | |
122 | tb10x_gpio = devm_kzalloc(dev, size: sizeof(*tb10x_gpio), GFP_KERNEL); |
123 | if (tb10x_gpio == NULL) |
124 | return -ENOMEM; |
125 | |
126 | tb10x_gpio->base = devm_platform_ioremap_resource(pdev, index: 0); |
127 | if (IS_ERR(ptr: tb10x_gpio->base)) |
128 | return PTR_ERR(ptr: tb10x_gpio->base); |
129 | |
130 | tb10x_gpio->gc.label = |
131 | devm_kasprintf(dev, GFP_KERNEL, fmt: "%pOF" , pdev->dev.of_node); |
132 | if (!tb10x_gpio->gc.label) |
133 | return -ENOMEM; |
134 | |
135 | /* |
136 | * Initialize generic GPIO with one single register for reading and setting |
137 | * the lines, no special set or clear registers and a data direction register |
138 | * wher 1 means "output". |
139 | */ |
140 | ret = bgpio_init(gc: &tb10x_gpio->gc, dev, sz: 4, |
141 | dat: tb10x_gpio->base + OFFSET_TO_REG_DATA, |
142 | NULL, |
143 | NULL, |
144 | dirout: tb10x_gpio->base + OFFSET_TO_REG_DDR, |
145 | NULL, |
146 | flags: 0); |
147 | if (ret) { |
148 | dev_err(dev, "unable to init generic GPIO\n" ); |
149 | return ret; |
150 | } |
151 | tb10x_gpio->gc.base = -1; |
152 | tb10x_gpio->gc.parent = dev; |
153 | tb10x_gpio->gc.owner = THIS_MODULE; |
154 | /* |
155 | * ngpio is set by bgpio_init() but we override it, this .request() |
156 | * callback also overrides the one set up by generic GPIO. |
157 | */ |
158 | tb10x_gpio->gc.ngpio = ngpio; |
159 | tb10x_gpio->gc.request = gpiochip_generic_request; |
160 | tb10x_gpio->gc.free = gpiochip_generic_free; |
161 | |
162 | ret = devm_gpiochip_add_data(dev, &tb10x_gpio->gc, tb10x_gpio); |
163 | if (ret < 0) { |
164 | dev_err(dev, "Could not add gpiochip.\n" ); |
165 | return ret; |
166 | } |
167 | |
168 | platform_set_drvdata(pdev, data: tb10x_gpio); |
169 | |
170 | if (of_property_read_bool(np, propname: "interrupt-controller" )) { |
171 | struct irq_chip_generic *gc; |
172 | |
173 | ret = platform_get_irq(pdev, 0); |
174 | if (ret < 0) |
175 | return ret; |
176 | |
177 | tb10x_gpio->gc.to_irq = tb10x_gpio_to_irq; |
178 | tb10x_gpio->irq = ret; |
179 | |
180 | ret = devm_request_irq(dev, irq: ret, handler: tb10x_gpio_irq_cascade, |
181 | IRQF_TRIGGER_NONE | IRQF_SHARED, |
182 | devname: dev_name(dev), dev_id: tb10x_gpio); |
183 | if (ret != 0) |
184 | return ret; |
185 | |
186 | tb10x_gpio->domain = irq_domain_add_linear(of_node: np, |
187 | size: tb10x_gpio->gc.ngpio, |
188 | ops: &irq_generic_chip_ops, NULL); |
189 | if (!tb10x_gpio->domain) { |
190 | return -ENOMEM; |
191 | } |
192 | |
193 | ret = irq_alloc_domain_generic_chips(tb10x_gpio->domain, |
194 | tb10x_gpio->gc.ngpio, 1, tb10x_gpio->gc.label, |
195 | handle_edge_irq, IRQ_NOREQUEST, IRQ_NOPROBE, |
196 | IRQ_GC_INIT_MASK_CACHE); |
197 | if (ret) |
198 | goto err_remove_domain; |
199 | |
200 | gc = tb10x_gpio->domain->gc->gc[0]; |
201 | gc->reg_base = tb10x_gpio->base; |
202 | gc->chip_types[0].type = IRQ_TYPE_EDGE_BOTH; |
203 | gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit; |
204 | gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; |
205 | gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; |
206 | gc->chip_types[0].chip.irq_set_type = tb10x_gpio_irq_set_type; |
207 | gc->chip_types[0].regs.ack = OFFSET_TO_REG_CHANGE; |
208 | gc->chip_types[0].regs.mask = OFFSET_TO_REG_INT_EN; |
209 | } |
210 | |
211 | return 0; |
212 | |
213 | err_remove_domain: |
214 | irq_domain_remove(host: tb10x_gpio->domain); |
215 | return ret; |
216 | } |
217 | |
218 | static void tb10x_gpio_remove(struct platform_device *pdev) |
219 | { |
220 | struct tb10x_gpio *tb10x_gpio = platform_get_drvdata(pdev); |
221 | |
222 | if (tb10x_gpio->gc.to_irq) { |
223 | irq_remove_generic_chip(gc: tb10x_gpio->domain->gc->gc[0], |
224 | BIT(tb10x_gpio->gc.ngpio) - 1, clr: 0, set: 0); |
225 | kfree(objp: tb10x_gpio->domain->gc); |
226 | irq_domain_remove(host: tb10x_gpio->domain); |
227 | } |
228 | } |
229 | |
230 | static const struct of_device_id tb10x_gpio_dt_ids[] = { |
231 | { .compatible = "abilis,tb10x-gpio" }, |
232 | { } |
233 | }; |
234 | MODULE_DEVICE_TABLE(of, tb10x_gpio_dt_ids); |
235 | |
236 | static struct platform_driver tb10x_gpio_driver = { |
237 | .probe = tb10x_gpio_probe, |
238 | .remove_new = tb10x_gpio_remove, |
239 | .driver = { |
240 | .name = "tb10x-gpio" , |
241 | .of_match_table = tb10x_gpio_dt_ids, |
242 | } |
243 | }; |
244 | |
245 | module_platform_driver(tb10x_gpio_driver); |
246 | MODULE_LICENSE("GPL" ); |
247 | MODULE_DESCRIPTION("tb10x gpio." ); |
248 | |