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 generic_handle_domain_irq(gc->irq.domain, bit); 99 mtk_gpio_w32(rg, GPIO_REG_STAT, BIT(bit)); 100 ret |= IRQ_HANDLED; 101 } 102 103 return ret; 104 } 105 106 static void 107 mediatek_gpio_irq_unmask(struct irq_data *d) 108 { 109 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 110 struct mtk_gc *rg = to_mediatek_gpio(gc); 111 int pin = d->hwirq; 112 unsigned long flags; 113 u32 rise, fall, high, low; 114 115 spin_lock_irqsave(&rg->lock, flags); 116 rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); 117 fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); 118 high = mtk_gpio_r32(rg, GPIO_REG_HLVL); 119 low = mtk_gpio_r32(rg, GPIO_REG_LLVL); 120 mtk_gpio_w32(rg, GPIO_REG_REDGE, rise | (BIT(pin) & rg->rising)); 121 mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall | (BIT(pin) & rg->falling)); 122 mtk_gpio_w32(rg, GPIO_REG_HLVL, high | (BIT(pin) & rg->hlevel)); 123 mtk_gpio_w32(rg, GPIO_REG_LLVL, low | (BIT(pin) & rg->llevel)); 124 spin_unlock_irqrestore(&rg->lock, flags); 125 } 126 127 static void 128 mediatek_gpio_irq_mask(struct irq_data *d) 129 { 130 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 131 struct mtk_gc *rg = to_mediatek_gpio(gc); 132 int pin = d->hwirq; 133 unsigned long flags; 134 u32 rise, fall, high, low; 135 136 spin_lock_irqsave(&rg->lock, flags); 137 rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); 138 fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); 139 high = mtk_gpio_r32(rg, GPIO_REG_HLVL); 140 low = mtk_gpio_r32(rg, GPIO_REG_LLVL); 141 mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall & ~BIT(pin)); 142 mtk_gpio_w32(rg, GPIO_REG_REDGE, rise & ~BIT(pin)); 143 mtk_gpio_w32(rg, GPIO_REG_HLVL, high & ~BIT(pin)); 144 mtk_gpio_w32(rg, GPIO_REG_LLVL, low & ~BIT(pin)); 145 spin_unlock_irqrestore(&rg->lock, flags); 146 } 147 148 static int 149 mediatek_gpio_irq_type(struct irq_data *d, unsigned int type) 150 { 151 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 152 struct mtk_gc *rg = to_mediatek_gpio(gc); 153 int pin = d->hwirq; 154 u32 mask = BIT(pin); 155 156 if (type == IRQ_TYPE_PROBE) { 157 if ((rg->rising | rg->falling | 158 rg->hlevel | rg->llevel) & mask) 159 return 0; 160 161 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; 162 } 163 164 rg->rising &= ~mask; 165 rg->falling &= ~mask; 166 rg->hlevel &= ~mask; 167 rg->llevel &= ~mask; 168 169 switch (type & IRQ_TYPE_SENSE_MASK) { 170 case IRQ_TYPE_EDGE_BOTH: 171 rg->rising |= mask; 172 rg->falling |= mask; 173 break; 174 case IRQ_TYPE_EDGE_RISING: 175 rg->rising |= mask; 176 break; 177 case IRQ_TYPE_EDGE_FALLING: 178 rg->falling |= mask; 179 break; 180 case IRQ_TYPE_LEVEL_HIGH: 181 rg->hlevel |= mask; 182 break; 183 case IRQ_TYPE_LEVEL_LOW: 184 rg->llevel |= mask; 185 break; 186 } 187 188 return 0; 189 } 190 191 static int 192 mediatek_gpio_xlate(struct gpio_chip *chip, 193 const struct of_phandle_args *spec, u32 *flags) 194 { 195 int gpio = spec->args[0]; 196 struct mtk_gc *rg = to_mediatek_gpio(chip); 197 198 if (rg->bank != gpio / MTK_BANK_WIDTH) 199 return -EINVAL; 200 201 if (flags) 202 *flags = spec->args[1]; 203 204 return gpio % MTK_BANK_WIDTH; 205 } 206 207 static int 208 mediatek_gpio_bank_probe(struct device *dev, 209 struct device_node *node, int bank) 210 { 211 struct mtk *mtk = dev_get_drvdata(dev); 212 struct mtk_gc *rg; 213 void __iomem *dat, *set, *ctrl, *diro; 214 int ret; 215 216 rg = &mtk->gc_map[bank]; 217 memset(rg, 0, sizeof(*rg)); 218 219 spin_lock_init(&rg->lock); 220 rg->chip.of_node = node; 221 rg->bank = bank; 222 223 dat = mtk->base + GPIO_REG_DATA + (rg->bank * GPIO_BANK_STRIDE); 224 set = mtk->base + GPIO_REG_DSET + (rg->bank * GPIO_BANK_STRIDE); 225 ctrl = mtk->base + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_STRIDE); 226 diro = mtk->base + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_STRIDE); 227 228 ret = bgpio_init(&rg->chip, dev, 4, dat, set, ctrl, diro, NULL, 229 BGPIOF_NO_SET_ON_INPUT); 230 if (ret) { 231 dev_err(dev, "bgpio_init() failed\n"); 232 return ret; 233 } 234 235 rg->chip.of_gpio_n_cells = 2; 236 rg->chip.of_xlate = mediatek_gpio_xlate; 237 rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", 238 dev_name(dev), bank); 239 if (!rg->chip.label) 240 return -ENOMEM; 241 242 rg->irq_chip.name = dev_name(dev); 243 rg->irq_chip.parent_device = dev; 244 rg->irq_chip.irq_unmask = mediatek_gpio_irq_unmask; 245 rg->irq_chip.irq_mask = mediatek_gpio_irq_mask; 246 rg->irq_chip.irq_mask_ack = mediatek_gpio_irq_mask; 247 rg->irq_chip.irq_set_type = mediatek_gpio_irq_type; 248 249 if (mtk->gpio_irq) { 250 struct gpio_irq_chip *girq; 251 252 /* 253 * Directly request the irq here instead of passing 254 * a flow-handler because the irq is shared. 255 */ 256 ret = devm_request_irq(dev, mtk->gpio_irq, 257 mediatek_gpio_irq_handler, IRQF_SHARED, 258 rg->chip.label, &rg->chip); 259 260 if (ret) { 261 dev_err(dev, "Error requesting IRQ %d: %d\n", 262 mtk->gpio_irq, ret); 263 return ret; 264 } 265 266 girq = &rg->chip.irq; 267 girq->chip = &rg->irq_chip; 268 /* This will let us handle the parent IRQ in the driver */ 269 girq->parent_handler = NULL; 270 girq->num_parents = 0; 271 girq->parents = NULL; 272 girq->default_type = IRQ_TYPE_NONE; 273 girq->handler = handle_simple_irq; 274 } 275 276 ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); 277 if (ret < 0) { 278 dev_err(dev, "Could not register gpio %d, ret=%d\n", 279 rg->chip.ngpio, ret); 280 return ret; 281 } 282 283 /* set polarity to low for all gpios */ 284 mtk_gpio_w32(rg, GPIO_REG_POL, 0); 285 286 dev_info(dev, "registering %d gpios\n", rg->chip.ngpio); 287 288 return 0; 289 } 290 291 static int 292 mediatek_gpio_probe(struct platform_device *pdev) 293 { 294 struct device *dev = &pdev->dev; 295 struct device_node *np = dev->of_node; 296 struct mtk *mtk; 297 int i; 298 int ret; 299 300 mtk = devm_kzalloc(dev, sizeof(*mtk), GFP_KERNEL); 301 if (!mtk) 302 return -ENOMEM; 303 304 mtk->base = devm_platform_ioremap_resource(pdev, 0); 305 if (IS_ERR(mtk->base)) 306 return PTR_ERR(mtk->base); 307 308 mtk->gpio_irq = irq_of_parse_and_map(np, 0); 309 mtk->dev = dev; 310 platform_set_drvdata(pdev, mtk); 311 312 for (i = 0; i < MTK_BANK_CNT; i++) { 313 ret = mediatek_gpio_bank_probe(dev, np, i); 314 if (ret) 315 return ret; 316 } 317 318 return 0; 319 } 320 321 static const struct of_device_id mediatek_gpio_match[] = { 322 { .compatible = "mediatek,mt7621-gpio" }, 323 {}, 324 }; 325 MODULE_DEVICE_TABLE(of, mediatek_gpio_match); 326 327 static struct platform_driver mediatek_gpio_driver = { 328 .probe = mediatek_gpio_probe, 329 .driver = { 330 .name = "mt7621_gpio", 331 .of_match_table = mediatek_gpio_match, 332 }, 333 }; 334 335 builtin_platform_driver(mediatek_gpio_driver); 336