1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org> 4 * Copyright (C) 2013 John Crispin <blogic@openwrt.org> 5 */ 6 7 #include <linux/err.h> 8 #include <linux/gpio/driver.h> 9 #include <linux/interrupt.h> 10 #include <linux/io.h> 11 #include <linux/module.h> 12 #include <linux/of_irq.h> 13 #include <linux/platform_device.h> 14 #include <linux/spinlock.h> 15 16 #define MTK_BANK_CNT 3 17 #define MTK_BANK_WIDTH 32 18 19 #define GPIO_BANK_STRIDE 0x04 20 #define GPIO_REG_CTRL 0x00 21 #define GPIO_REG_POL 0x10 22 #define GPIO_REG_DATA 0x20 23 #define GPIO_REG_DSET 0x30 24 #define GPIO_REG_DCLR 0x40 25 #define GPIO_REG_REDGE 0x50 26 #define GPIO_REG_FEDGE 0x60 27 #define GPIO_REG_HLVL 0x70 28 #define GPIO_REG_LLVL 0x80 29 #define GPIO_REG_STAT 0x90 30 #define GPIO_REG_EDGE 0xA0 31 32 struct mtk_gc { 33 struct irq_chip irq_chip; 34 struct gpio_chip chip; 35 spinlock_t lock; 36 int bank; 37 u32 rising; 38 u32 falling; 39 u32 hlevel; 40 u32 llevel; 41 }; 42 43 /** 44 * struct mtk - state container for 45 * data of the platform driver. It is 3 46 * separate gpio-chip each one with its 47 * own irq_chip. 48 * @dev: device instance 49 * @base: memory base address 50 * @gpio_irq: irq number from the device tree 51 * @gc_map: array of the gpio chips 52 */ 53 struct mtk { 54 struct device *dev; 55 void __iomem *base; 56 int gpio_irq; 57 struct mtk_gc gc_map[MTK_BANK_CNT]; 58 }; 59 60 static inline struct mtk_gc * 61 to_mediatek_gpio(struct gpio_chip *chip) 62 { 63 return container_of(chip, struct mtk_gc, chip); 64 } 65 66 static inline void 67 mtk_gpio_w32(struct mtk_gc *rg, u32 offset, u32 val) 68 { 69 struct gpio_chip *gc = &rg->chip; 70 struct mtk *mtk = gpiochip_get_data(gc); 71 72 offset = (rg->bank * GPIO_BANK_STRIDE) + offset; 73 gc->write_reg(mtk->base + offset, val); 74 } 75 76 static inline u32 77 mtk_gpio_r32(struct mtk_gc *rg, u32 offset) 78 { 79 struct gpio_chip *gc = &rg->chip; 80 struct mtk *mtk = gpiochip_get_data(gc); 81 82 offset = (rg->bank * GPIO_BANK_STRIDE) + offset; 83 return gc->read_reg(mtk->base + offset); 84 } 85 86 static irqreturn_t 87 mediatek_gpio_irq_handler(int irq, void *data) 88 { 89 struct gpio_chip *gc = data; 90 struct mtk_gc *rg = to_mediatek_gpio(gc); 91 irqreturn_t ret = IRQ_NONE; 92 unsigned long pending; 93 int bit; 94 95 pending = mtk_gpio_r32(rg, GPIO_REG_STAT); 96 97 for_each_set_bit(bit, &pending, MTK_BANK_WIDTH) { 98 u32 map = irq_find_mapping(gc->irq.domain, bit); 99 100 generic_handle_irq(map); 101 mtk_gpio_w32(rg, GPIO_REG_STAT, BIT(bit)); 102 ret |= IRQ_HANDLED; 103 } 104 105 return ret; 106 } 107 108 static void 109 mediatek_gpio_irq_unmask(struct irq_data *d) 110 { 111 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 112 struct mtk_gc *rg = to_mediatek_gpio(gc); 113 int pin = d->hwirq; 114 unsigned long flags; 115 u32 rise, fall, high, low; 116 117 spin_lock_irqsave(&rg->lock, flags); 118 rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); 119 fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); 120 high = mtk_gpio_r32(rg, GPIO_REG_HLVL); 121 low = mtk_gpio_r32(rg, GPIO_REG_LLVL); 122 mtk_gpio_w32(rg, GPIO_REG_REDGE, rise | (BIT(pin) & rg->rising)); 123 mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall | (BIT(pin) & rg->falling)); 124 mtk_gpio_w32(rg, GPIO_REG_HLVL, high | (BIT(pin) & rg->hlevel)); 125 mtk_gpio_w32(rg, GPIO_REG_LLVL, low | (BIT(pin) & rg->llevel)); 126 spin_unlock_irqrestore(&rg->lock, flags); 127 } 128 129 static void 130 mediatek_gpio_irq_mask(struct irq_data *d) 131 { 132 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 133 struct mtk_gc *rg = to_mediatek_gpio(gc); 134 int pin = d->hwirq; 135 unsigned long flags; 136 u32 rise, fall, high, low; 137 138 spin_lock_irqsave(&rg->lock, flags); 139 rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); 140 fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); 141 high = mtk_gpio_r32(rg, GPIO_REG_HLVL); 142 low = mtk_gpio_r32(rg, GPIO_REG_LLVL); 143 mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall & ~BIT(pin)); 144 mtk_gpio_w32(rg, GPIO_REG_REDGE, rise & ~BIT(pin)); 145 mtk_gpio_w32(rg, GPIO_REG_HLVL, high & ~BIT(pin)); 146 mtk_gpio_w32(rg, GPIO_REG_LLVL, low & ~BIT(pin)); 147 spin_unlock_irqrestore(&rg->lock, flags); 148 } 149 150 static int 151 mediatek_gpio_irq_type(struct irq_data *d, unsigned int type) 152 { 153 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 154 struct mtk_gc *rg = to_mediatek_gpio(gc); 155 int pin = d->hwirq; 156 u32 mask = BIT(pin); 157 158 if (type == IRQ_TYPE_PROBE) { 159 if ((rg->rising | rg->falling | 160 rg->hlevel | rg->llevel) & mask) 161 return 0; 162 163 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; 164 } 165 166 rg->rising &= ~mask; 167 rg->falling &= ~mask; 168 rg->hlevel &= ~mask; 169 rg->llevel &= ~mask; 170 171 switch (type & IRQ_TYPE_SENSE_MASK) { 172 case IRQ_TYPE_EDGE_BOTH: 173 rg->rising |= mask; 174 rg->falling |= mask; 175 break; 176 case IRQ_TYPE_EDGE_RISING: 177 rg->rising |= mask; 178 break; 179 case IRQ_TYPE_EDGE_FALLING: 180 rg->falling |= mask; 181 break; 182 case IRQ_TYPE_LEVEL_HIGH: 183 rg->hlevel |= mask; 184 break; 185 case IRQ_TYPE_LEVEL_LOW: 186 rg->llevel |= mask; 187 break; 188 } 189 190 return 0; 191 } 192 193 static int 194 mediatek_gpio_xlate(struct gpio_chip *chip, 195 const struct of_phandle_args *spec, u32 *flags) 196 { 197 int gpio = spec->args[0]; 198 struct mtk_gc *rg = to_mediatek_gpio(chip); 199 200 if (rg->bank != gpio / MTK_BANK_WIDTH) 201 return -EINVAL; 202 203 if (flags) 204 *flags = spec->args[1]; 205 206 return gpio % MTK_BANK_WIDTH; 207 } 208 209 static int 210 mediatek_gpio_bank_probe(struct device *dev, 211 struct device_node *node, int bank) 212 { 213 struct mtk *mtk = dev_get_drvdata(dev); 214 struct mtk_gc *rg; 215 void __iomem *dat, *set, *ctrl, *diro; 216 int ret; 217 218 rg = &mtk->gc_map[bank]; 219 memset(rg, 0, sizeof(*rg)); 220 221 spin_lock_init(&rg->lock); 222 rg->chip.of_node = node; 223 rg->bank = bank; 224 225 dat = mtk->base + GPIO_REG_DATA + (rg->bank * GPIO_BANK_STRIDE); 226 set = mtk->base + GPIO_REG_DSET + (rg->bank * GPIO_BANK_STRIDE); 227 ctrl = mtk->base + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_STRIDE); 228 diro = mtk->base + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_STRIDE); 229 230 ret = bgpio_init(&rg->chip, dev, 4, 231 dat, set, ctrl, diro, NULL, 0); 232 if (ret) { 233 dev_err(dev, "bgpio_init() failed\n"); 234 return ret; 235 } 236 237 rg->chip.of_gpio_n_cells = 2; 238 rg->chip.of_xlate = mediatek_gpio_xlate; 239 rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", 240 dev_name(dev), bank); 241 if (!rg->chip.label) 242 return -ENOMEM; 243 244 rg->irq_chip.name = dev_name(dev); 245 rg->irq_chip.parent_device = dev; 246 rg->irq_chip.irq_unmask = mediatek_gpio_irq_unmask; 247 rg->irq_chip.irq_mask = mediatek_gpio_irq_mask; 248 rg->irq_chip.irq_mask_ack = mediatek_gpio_irq_mask; 249 rg->irq_chip.irq_set_type = mediatek_gpio_irq_type; 250 251 if (mtk->gpio_irq) { 252 struct gpio_irq_chip *girq; 253 254 /* 255 * Directly request the irq here instead of passing 256 * a flow-handler because the irq is shared. 257 */ 258 ret = devm_request_irq(dev, mtk->gpio_irq, 259 mediatek_gpio_irq_handler, IRQF_SHARED, 260 rg->chip.label, &rg->chip); 261 262 if (ret) { 263 dev_err(dev, "Error requesting IRQ %d: %d\n", 264 mtk->gpio_irq, ret); 265 return ret; 266 } 267 268 girq = &rg->chip.irq; 269 girq->chip = &rg->irq_chip; 270 /* This will let us handle the parent IRQ in the driver */ 271 girq->parent_handler = NULL; 272 girq->num_parents = 0; 273 girq->parents = NULL; 274 girq->default_type = IRQ_TYPE_NONE; 275 girq->handler = handle_simple_irq; 276 } 277 278 ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); 279 if (ret < 0) { 280 dev_err(dev, "Could not register gpio %d, ret=%d\n", 281 rg->chip.ngpio, ret); 282 return ret; 283 } 284 285 /* set polarity to low for all gpios */ 286 mtk_gpio_w32(rg, GPIO_REG_POL, 0); 287 288 dev_info(dev, "registering %d gpios\n", rg->chip.ngpio); 289 290 return 0; 291 } 292 293 static int 294 mediatek_gpio_probe(struct platform_device *pdev) 295 { 296 struct device *dev = &pdev->dev; 297 struct device_node *np = dev->of_node; 298 struct mtk *mtk; 299 int i; 300 int ret; 301 302 mtk = devm_kzalloc(dev, sizeof(*mtk), GFP_KERNEL); 303 if (!mtk) 304 return -ENOMEM; 305 306 mtk->base = devm_platform_ioremap_resource(pdev, 0); 307 if (IS_ERR(mtk->base)) 308 return PTR_ERR(mtk->base); 309 310 mtk->gpio_irq = irq_of_parse_and_map(np, 0); 311 mtk->dev = dev; 312 platform_set_drvdata(pdev, mtk); 313 314 for (i = 0; i < MTK_BANK_CNT; i++) { 315 ret = mediatek_gpio_bank_probe(dev, np, i); 316 if (ret) 317 return ret; 318 } 319 320 return 0; 321 } 322 323 static const struct of_device_id mediatek_gpio_match[] = { 324 { .compatible = "mediatek,mt7621-gpio" }, 325 {}, 326 }; 327 MODULE_DEVICE_TABLE(of, mediatek_gpio_match); 328 329 static struct platform_driver mediatek_gpio_driver = { 330 .probe = mediatek_gpio_probe, 331 .driver = { 332 .name = "mt7621_gpio", 333 .of_match_table = mediatek_gpio_match, 334 }, 335 }; 336 337 builtin_platform_driver(mediatek_gpio_driver); 338