1 /* 2 * Emma Mobile GPIO Support - GIO 3 * 4 * Copyright (C) 2012 Magnus Damm 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/init.h> 21 #include <linux/platform_device.h> 22 #include <linux/spinlock.h> 23 #include <linux/interrupt.h> 24 #include <linux/ioport.h> 25 #include <linux/io.h> 26 #include <linux/irq.h> 27 #include <linux/irqdomain.h> 28 #include <linux/bitops.h> 29 #include <linux/err.h> 30 #include <linux/gpio.h> 31 #include <linux/slab.h> 32 #include <linux/module.h> 33 #include <linux/platform_data/gpio-em.h> 34 35 struct em_gio_priv { 36 void __iomem *base0; 37 void __iomem *base1; 38 spinlock_t sense_lock; 39 struct platform_device *pdev; 40 struct gpio_chip gpio_chip; 41 struct irq_chip irq_chip; 42 struct irq_domain *irq_domain; 43 }; 44 45 #define GIO_E1 0x00 46 #define GIO_E0 0x04 47 #define GIO_EM 0x04 48 #define GIO_OL 0x08 49 #define GIO_OH 0x0c 50 #define GIO_I 0x10 51 #define GIO_IIA 0x14 52 #define GIO_IEN 0x18 53 #define GIO_IDS 0x1c 54 #define GIO_IIM 0x1c 55 #define GIO_RAW 0x20 56 #define GIO_MST 0x24 57 #define GIO_IIR 0x28 58 59 #define GIO_IDT0 0x40 60 #define GIO_IDT1 0x44 61 #define GIO_IDT2 0x48 62 #define GIO_IDT3 0x4c 63 #define GIO_RAWBL 0x50 64 #define GIO_RAWBH 0x54 65 #define GIO_IRBL 0x58 66 #define GIO_IRBH 0x5c 67 68 #define GIO_IDT(n) (GIO_IDT0 + ((n) * 4)) 69 70 static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs) 71 { 72 if (offs < GIO_IDT0) 73 return ioread32(p->base0 + offs); 74 else 75 return ioread32(p->base1 + (offs - GIO_IDT0)); 76 } 77 78 static inline void em_gio_write(struct em_gio_priv *p, int offs, 79 unsigned long value) 80 { 81 if (offs < GIO_IDT0) 82 iowrite32(value, p->base0 + offs); 83 else 84 iowrite32(value, p->base1 + (offs - GIO_IDT0)); 85 } 86 87 static void em_gio_irq_disable(struct irq_data *d) 88 { 89 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 90 91 em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d))); 92 } 93 94 static void em_gio_irq_enable(struct irq_data *d) 95 { 96 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 97 98 em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d))); 99 } 100 101 #define GIO_ASYNC(x) (x + 8) 102 103 static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = { 104 [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00), 105 [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01), 106 [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02), 107 [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03), 108 [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04), 109 }; 110 111 static int em_gio_irq_set_type(struct irq_data *d, unsigned int type) 112 { 113 unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK]; 114 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 115 unsigned int reg, offset, shift; 116 unsigned long flags; 117 unsigned long tmp; 118 119 if (!value) 120 return -EINVAL; 121 122 offset = irqd_to_hwirq(d); 123 124 pr_debug("gio: sense irq = %d, mode = %d\n", offset, value); 125 126 /* 8 x 4 bit fields in 4 IDT registers */ 127 reg = GIO_IDT(offset >> 3); 128 shift = (offset & 0x07) << 4; 129 130 spin_lock_irqsave(&p->sense_lock, flags); 131 132 /* disable the interrupt in IIA */ 133 tmp = em_gio_read(p, GIO_IIA); 134 tmp &= ~BIT(offset); 135 em_gio_write(p, GIO_IIA, tmp); 136 137 /* change the sense setting in IDT */ 138 tmp = em_gio_read(p, reg); 139 tmp &= ~(0xf << shift); 140 tmp |= value << shift; 141 em_gio_write(p, reg, tmp); 142 143 /* clear pending interrupts */ 144 em_gio_write(p, GIO_IIR, BIT(offset)); 145 146 /* enable the interrupt in IIA */ 147 tmp = em_gio_read(p, GIO_IIA); 148 tmp |= BIT(offset); 149 em_gio_write(p, GIO_IIA, tmp); 150 151 spin_unlock_irqrestore(&p->sense_lock, flags); 152 153 return 0; 154 } 155 156 static irqreturn_t em_gio_irq_handler(int irq, void *dev_id) 157 { 158 struct em_gio_priv *p = dev_id; 159 unsigned long pending; 160 unsigned int offset, irqs_handled = 0; 161 162 while ((pending = em_gio_read(p, GIO_MST))) { 163 offset = __ffs(pending); 164 em_gio_write(p, GIO_IIR, BIT(offset)); 165 generic_handle_irq(irq_find_mapping(p->irq_domain, offset)); 166 irqs_handled++; 167 } 168 169 return irqs_handled ? IRQ_HANDLED : IRQ_NONE; 170 } 171 172 static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip) 173 { 174 return container_of(chip, struct em_gio_priv, gpio_chip); 175 } 176 177 static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset) 178 { 179 em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset)); 180 return 0; 181 } 182 183 static int em_gio_get(struct gpio_chip *chip, unsigned offset) 184 { 185 return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset)); 186 } 187 188 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg, 189 unsigned shift, int value) 190 { 191 /* upper 16 bits contains mask and lower 16 actual value */ 192 em_gio_write(gpio_to_priv(chip), reg, 193 (1 << (shift + 16)) | (value << shift)); 194 } 195 196 static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value) 197 { 198 /* output is split into two registers */ 199 if (offset < 16) 200 __em_gio_set(chip, GIO_OL, offset, value); 201 else 202 __em_gio_set(chip, GIO_OH, offset - 16, value); 203 } 204 205 static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset, 206 int value) 207 { 208 /* write GPIO value to output before selecting output mode of pin */ 209 em_gio_set(chip, offset, value); 210 em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset)); 211 return 0; 212 } 213 214 static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset) 215 { 216 return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); 217 } 218 219 static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int virq, 220 irq_hw_number_t hw) 221 { 222 struct em_gio_priv *p = h->host_data; 223 224 pr_debug("gio: map hw irq = %d, virq = %d\n", (int)hw, virq); 225 226 irq_set_chip_data(virq, h->host_data); 227 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); 228 set_irq_flags(virq, IRQF_VALID); /* kill me now */ 229 return 0; 230 } 231 232 static struct irq_domain_ops em_gio_irq_domain_ops = { 233 .map = em_gio_irq_domain_map, 234 }; 235 236 static int em_gio_probe(struct platform_device *pdev) 237 { 238 struct gpio_em_config *pdata = pdev->dev.platform_data; 239 struct em_gio_priv *p; 240 struct resource *io[2], *irq[2]; 241 struct gpio_chip *gpio_chip; 242 struct irq_chip *irq_chip; 243 const char *name = dev_name(&pdev->dev); 244 int ret; 245 246 p = kzalloc(sizeof(*p), GFP_KERNEL); 247 if (!p) { 248 dev_err(&pdev->dev, "failed to allocate driver data\n"); 249 ret = -ENOMEM; 250 goto err0; 251 } 252 253 p->pdev = pdev; 254 platform_set_drvdata(pdev, p); 255 spin_lock_init(&p->sense_lock); 256 257 io[0] = platform_get_resource(pdev, IORESOURCE_MEM, 0); 258 io[1] = platform_get_resource(pdev, IORESOURCE_MEM, 1); 259 irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 260 irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1); 261 262 if (!io[0] || !io[1] || !irq[0] || !irq[1] || !pdata) { 263 dev_err(&pdev->dev, "missing IRQ, IOMEM or configuration\n"); 264 ret = -EINVAL; 265 goto err1; 266 } 267 268 p->base0 = ioremap_nocache(io[0]->start, resource_size(io[0])); 269 if (!p->base0) { 270 dev_err(&pdev->dev, "failed to remap low I/O memory\n"); 271 ret = -ENXIO; 272 goto err1; 273 } 274 275 p->base1 = ioremap_nocache(io[1]->start, resource_size(io[1])); 276 if (!p->base1) { 277 dev_err(&pdev->dev, "failed to remap high I/O memory\n"); 278 ret = -ENXIO; 279 goto err2; 280 } 281 282 gpio_chip = &p->gpio_chip; 283 gpio_chip->direction_input = em_gio_direction_input; 284 gpio_chip->get = em_gio_get; 285 gpio_chip->direction_output = em_gio_direction_output; 286 gpio_chip->set = em_gio_set; 287 gpio_chip->to_irq = em_gio_to_irq; 288 gpio_chip->label = name; 289 gpio_chip->owner = THIS_MODULE; 290 gpio_chip->base = pdata->gpio_base; 291 gpio_chip->ngpio = pdata->number_of_pins; 292 293 irq_chip = &p->irq_chip; 294 irq_chip->name = name; 295 irq_chip->irq_mask = em_gio_irq_disable; 296 irq_chip->irq_unmask = em_gio_irq_enable; 297 irq_chip->irq_enable = em_gio_irq_enable; 298 irq_chip->irq_disable = em_gio_irq_disable; 299 irq_chip->irq_set_type = em_gio_irq_set_type; 300 irq_chip->flags = IRQCHIP_SKIP_SET_WAKE; 301 302 p->irq_domain = irq_domain_add_linear(pdev->dev.of_node, 303 pdata->number_of_pins, 304 &em_gio_irq_domain_ops, p); 305 if (!p->irq_domain) { 306 ret = -ENXIO; 307 dev_err(&pdev->dev, "cannot initialize irq domain\n"); 308 goto err3; 309 } 310 311 if (request_irq(irq[0]->start, em_gio_irq_handler, 0, name, p)) { 312 dev_err(&pdev->dev, "failed to request low IRQ\n"); 313 ret = -ENOENT; 314 goto err4; 315 } 316 317 if (request_irq(irq[1]->start, em_gio_irq_handler, 0, name, p)) { 318 dev_err(&pdev->dev, "failed to request high IRQ\n"); 319 ret = -ENOENT; 320 goto err5; 321 } 322 323 ret = gpiochip_add(gpio_chip); 324 if (ret) { 325 dev_err(&pdev->dev, "failed to add GPIO controller\n"); 326 goto err6; 327 } 328 return 0; 329 330 err6: 331 free_irq(irq[1]->start, pdev); 332 err5: 333 free_irq(irq[0]->start, pdev); 334 err4: 335 irq_domain_remove(p->irq_domain); 336 err3: 337 iounmap(p->base1); 338 err2: 339 iounmap(p->base0); 340 err1: 341 kfree(p); 342 err0: 343 return ret; 344 } 345 346 static int em_gio_remove(struct platform_device *pdev) 347 { 348 struct em_gio_priv *p = platform_get_drvdata(pdev); 349 struct resource *irq[2]; 350 int ret; 351 352 ret = gpiochip_remove(&p->gpio_chip); 353 if (ret) 354 return ret; 355 356 irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 357 irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1); 358 359 free_irq(irq[1]->start, pdev); 360 free_irq(irq[0]->start, pdev); 361 irq_domain_remove(p->irq_domain); 362 iounmap(p->base1); 363 iounmap(p->base0); 364 kfree(p); 365 return 0; 366 } 367 368 static struct platform_driver em_gio_device_driver = { 369 .probe = em_gio_probe, 370 .remove = em_gio_remove, 371 .driver = { 372 .name = "em_gio", 373 } 374 }; 375 376 module_platform_driver(em_gio_device_driver); 377 378 MODULE_AUTHOR("Magnus Damm"); 379 MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver"); 380 MODULE_LICENSE("GPL v2"); 381