1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Loongson GPIO Support
4 *
5 * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/spinlock.h>
12 #include <linux/err.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/platform_device.h>
15 #include <linux/bitops.h>
16 #include <asm/types.h>
17
18 enum loongson_gpio_mode {
19 BIT_CTRL_MODE,
20 BYTE_CTRL_MODE,
21 };
22
23 struct loongson_gpio_chip_data {
24 const char *label;
25 enum loongson_gpio_mode mode;
26 unsigned int conf_offset;
27 unsigned int out_offset;
28 unsigned int in_offset;
29 unsigned int inten_offset;
30 };
31
32 struct loongson_gpio_chip {
33 struct gpio_chip chip;
34 struct fwnode_handle *fwnode;
35 spinlock_t lock;
36 void __iomem *reg_base;
37 const struct loongson_gpio_chip_data *chip_data;
38 };
39
to_loongson_gpio_chip(struct gpio_chip * chip)40 static inline struct loongson_gpio_chip *to_loongson_gpio_chip(struct gpio_chip *chip)
41 {
42 return container_of(chip, struct loongson_gpio_chip, chip);
43 }
44
loongson_commit_direction(struct loongson_gpio_chip * lgpio,unsigned int pin,int input)45 static inline void loongson_commit_direction(struct loongson_gpio_chip *lgpio, unsigned int pin,
46 int input)
47 {
48 u8 bval = input ? 1 : 0;
49
50 writeb(bval, lgpio->reg_base + lgpio->chip_data->conf_offset + pin);
51 }
52
loongson_commit_level(struct loongson_gpio_chip * lgpio,unsigned int pin,int high)53 static void loongson_commit_level(struct loongson_gpio_chip *lgpio, unsigned int pin, int high)
54 {
55 u8 bval = high ? 1 : 0;
56
57 writeb(bval, lgpio->reg_base + lgpio->chip_data->out_offset + pin);
58 }
59
loongson_gpio_direction_input(struct gpio_chip * chip,unsigned int pin)60 static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
61 {
62 unsigned long flags;
63 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
64
65 spin_lock_irqsave(&lgpio->lock, flags);
66 loongson_commit_direction(lgpio, pin, 1);
67 spin_unlock_irqrestore(&lgpio->lock, flags);
68
69 return 0;
70 }
71
loongson_gpio_direction_output(struct gpio_chip * chip,unsigned int pin,int value)72 static int loongson_gpio_direction_output(struct gpio_chip *chip, unsigned int pin, int value)
73 {
74 unsigned long flags;
75 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
76
77 spin_lock_irqsave(&lgpio->lock, flags);
78 loongson_commit_level(lgpio, pin, value);
79 loongson_commit_direction(lgpio, pin, 0);
80 spin_unlock_irqrestore(&lgpio->lock, flags);
81
82 return 0;
83 }
84
loongson_gpio_get(struct gpio_chip * chip,unsigned int pin)85 static int loongson_gpio_get(struct gpio_chip *chip, unsigned int pin)
86 {
87 u8 bval;
88 int val;
89 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
90
91 bval = readb(lgpio->reg_base + lgpio->chip_data->in_offset + pin);
92 val = bval & 1;
93
94 return val;
95 }
96
loongson_gpio_get_direction(struct gpio_chip * chip,unsigned int pin)97 static int loongson_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
98 {
99 u8 bval;
100 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
101
102 bval = readb(lgpio->reg_base + lgpio->chip_data->conf_offset + pin);
103 if (bval & 1)
104 return GPIO_LINE_DIRECTION_IN;
105
106 return GPIO_LINE_DIRECTION_OUT;
107 }
108
loongson_gpio_set(struct gpio_chip * chip,unsigned int pin,int value)109 static void loongson_gpio_set(struct gpio_chip *chip, unsigned int pin, int value)
110 {
111 unsigned long flags;
112 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
113
114 spin_lock_irqsave(&lgpio->lock, flags);
115 loongson_commit_level(lgpio, pin, value);
116 spin_unlock_irqrestore(&lgpio->lock, flags);
117 }
118
loongson_gpio_to_irq(struct gpio_chip * chip,unsigned int offset)119 static int loongson_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
120 {
121 unsigned int u;
122 struct platform_device *pdev = to_platform_device(chip->parent);
123 struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
124
125 if (lgpio->chip_data->mode == BIT_CTRL_MODE) {
126 /* Get the register index from offset then multiply by bytes per register */
127 u = readl(lgpio->reg_base + lgpio->chip_data->inten_offset + (offset / 32) * 4);
128 u |= BIT(offset % 32);
129 writel(u, lgpio->reg_base + lgpio->chip_data->inten_offset + (offset / 32) * 4);
130 } else {
131 writeb(1, lgpio->reg_base + lgpio->chip_data->inten_offset + offset);
132 }
133
134 return platform_get_irq(pdev, offset);
135 }
136
loongson_gpio_init(struct device * dev,struct loongson_gpio_chip * lgpio,void __iomem * reg_base)137 static int loongson_gpio_init(struct device *dev, struct loongson_gpio_chip *lgpio,
138 void __iomem *reg_base)
139 {
140 int ret;
141 u32 ngpios;
142
143 lgpio->reg_base = reg_base;
144 if (lgpio->chip_data->mode == BIT_CTRL_MODE) {
145 ret = bgpio_init(&lgpio->chip, dev, 8,
146 lgpio->reg_base + lgpio->chip_data->in_offset,
147 lgpio->reg_base + lgpio->chip_data->out_offset,
148 NULL, NULL,
149 lgpio->reg_base + lgpio->chip_data->conf_offset,
150 0);
151 if (ret) {
152 dev_err(dev, "unable to init generic GPIO\n");
153 return ret;
154 }
155 } else {
156 lgpio->chip.direction_input = loongson_gpio_direction_input;
157 lgpio->chip.get = loongson_gpio_get;
158 lgpio->chip.get_direction = loongson_gpio_get_direction;
159 lgpio->chip.direction_output = loongson_gpio_direction_output;
160 lgpio->chip.set = loongson_gpio_set;
161 lgpio->chip.parent = dev;
162 device_property_read_u32(dev, "ngpios", &ngpios);
163 lgpio->chip.ngpio = ngpios;
164 spin_lock_init(&lgpio->lock);
165 }
166
167 lgpio->chip.label = lgpio->chip_data->label;
168 lgpio->chip.can_sleep = false;
169 if (lgpio->chip_data->inten_offset)
170 lgpio->chip.to_irq = loongson_gpio_to_irq;
171
172 return devm_gpiochip_add_data(dev, &lgpio->chip, lgpio);
173 }
174
loongson_gpio_probe(struct platform_device * pdev)175 static int loongson_gpio_probe(struct platform_device *pdev)
176 {
177 void __iomem *reg_base;
178 struct loongson_gpio_chip *lgpio;
179 struct device *dev = &pdev->dev;
180
181 lgpio = devm_kzalloc(dev, sizeof(*lgpio), GFP_KERNEL);
182 if (!lgpio)
183 return -ENOMEM;
184
185 lgpio->chip_data = device_get_match_data(dev);
186
187 reg_base = devm_platform_ioremap_resource(pdev, 0);
188 if (IS_ERR(reg_base))
189 return PTR_ERR(reg_base);
190
191 return loongson_gpio_init(dev, lgpio, reg_base);
192 }
193
194 static const struct loongson_gpio_chip_data loongson_gpio_ls2k_data = {
195 .label = "ls2k_gpio",
196 .mode = BIT_CTRL_MODE,
197 .conf_offset = 0x0,
198 .in_offset = 0x20,
199 .out_offset = 0x10,
200 .inten_offset = 0x30,
201 };
202
203 static const struct loongson_gpio_chip_data loongson_gpio_ls2k0500_data0 = {
204 .label = "ls2k0500_gpio",
205 .mode = BIT_CTRL_MODE,
206 .conf_offset = 0x0,
207 .in_offset = 0x8,
208 .out_offset = 0x10,
209 .inten_offset = 0xb0,
210 };
211
212 static const struct loongson_gpio_chip_data loongson_gpio_ls2k0500_data1 = {
213 .label = "ls2k0500_gpio",
214 .mode = BIT_CTRL_MODE,
215 .conf_offset = 0x0,
216 .in_offset = 0x8,
217 .out_offset = 0x10,
218 .inten_offset = 0x98,
219 };
220
221 static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data0 = {
222 .label = "ls2k2000_gpio",
223 .mode = BIT_CTRL_MODE,
224 .conf_offset = 0x0,
225 .in_offset = 0xc,
226 .out_offset = 0x8,
227 };
228
229 static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data1 = {
230 .label = "ls2k2000_gpio",
231 .mode = BIT_CTRL_MODE,
232 .conf_offset = 0x0,
233 .in_offset = 0x20,
234 .out_offset = 0x10,
235 };
236
237 static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data2 = {
238 .label = "ls2k2000_gpio",
239 .mode = BIT_CTRL_MODE,
240 .conf_offset = 0x84,
241 .in_offset = 0x88,
242 .out_offset = 0x80,
243 };
244
245 static const struct loongson_gpio_chip_data loongson_gpio_ls3a5000_data = {
246 .label = "ls3a5000_gpio",
247 .mode = BIT_CTRL_MODE,
248 .conf_offset = 0x0,
249 .in_offset = 0xc,
250 .out_offset = 0x8,
251 };
252
253 static const struct loongson_gpio_chip_data loongson_gpio_ls7a_data = {
254 .label = "ls7a_gpio",
255 .mode = BYTE_CTRL_MODE,
256 .conf_offset = 0x800,
257 .in_offset = 0xa00,
258 .out_offset = 0x900,
259 };
260
261 static const struct of_device_id loongson_gpio_of_match[] = {
262 {
263 .compatible = "loongson,ls2k-gpio",
264 .data = &loongson_gpio_ls2k_data,
265 },
266 {
267 .compatible = "loongson,ls2k0500-gpio0",
268 .data = &loongson_gpio_ls2k0500_data0,
269 },
270 {
271 .compatible = "loongson,ls2k0500-gpio1",
272 .data = &loongson_gpio_ls2k0500_data1,
273 },
274 {
275 .compatible = "loongson,ls2k2000-gpio0",
276 .data = &loongson_gpio_ls2k2000_data0,
277 },
278 {
279 .compatible = "loongson,ls2k2000-gpio1",
280 .data = &loongson_gpio_ls2k2000_data1,
281 },
282 {
283 .compatible = "loongson,ls2k2000-gpio2",
284 .data = &loongson_gpio_ls2k2000_data2,
285 },
286 {
287 .compatible = "loongson,ls3a5000-gpio",
288 .data = &loongson_gpio_ls3a5000_data,
289 },
290 {
291 .compatible = "loongson,ls7a-gpio",
292 .data = &loongson_gpio_ls7a_data,
293 },
294 {}
295 };
296 MODULE_DEVICE_TABLE(of, loongson_gpio_of_match);
297
298 static const struct acpi_device_id loongson_gpio_acpi_match[] = {
299 {
300 .id = "LOON0002",
301 .driver_data = (kernel_ulong_t)&loongson_gpio_ls7a_data,
302 },
303 {
304 .id = "LOON0007",
305 .driver_data = (kernel_ulong_t)&loongson_gpio_ls3a5000_data,
306 },
307 {
308 .id = "LOON000A",
309 .driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data0,
310 },
311 {
312 .id = "LOON000B",
313 .driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data1,
314 },
315 {
316 .id = "LOON000C",
317 .driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data2,
318 },
319 {}
320 };
321 MODULE_DEVICE_TABLE(acpi, loongson_gpio_acpi_match);
322
323 static struct platform_driver loongson_gpio_driver = {
324 .driver = {
325 .name = "loongson-gpio",
326 .of_match_table = loongson_gpio_of_match,
327 .acpi_match_table = loongson_gpio_acpi_match,
328 },
329 .probe = loongson_gpio_probe,
330 };
331
loongson_gpio_setup(void)332 static int __init loongson_gpio_setup(void)
333 {
334 return platform_driver_register(&loongson_gpio_driver);
335 }
336 postcore_initcall(loongson_gpio_setup);
337
338 MODULE_DESCRIPTION("Loongson gpio driver");
339 MODULE_LICENSE("GPL");
340