drivers/gpio/gpio-etraxfs.c

   1 #include <linux/kernel.h>
   2 #include <linux/init.h>
   3 #include <linux/gpio/driver.h>
   4 #include <linux/of_gpio.h>
   5 #include <linux/io.h>
   6 #include <linux/interrupt.h>
   7 #include <linux/platform_device.h>
   8
   9 #define ETRAX_FS_rw_pa_dout     0
  10 #define ETRAX_FS_r_pa_din       4
  11 #define ETRAX_FS_rw_pa_oe       8
  12 #define ETRAX_FS_rw_intr_cfg    12
  13 #define ETRAX_FS_rw_intr_mask   16
  14 #define ETRAX_FS_rw_ack_intr    20
  15 #define ETRAX_FS_r_intr         24
  16 #define ETRAX_FS_r_masked_intr  28
  17 #define ETRAX_FS_rw_pb_dout     32
  18 #define ETRAX_FS_r_pb_din       36
  19 #define ETRAX_FS_rw_pb_oe       40
  20 #define ETRAX_FS_rw_pc_dout     48
  21 #define ETRAX_FS_r_pc_din       52
  22 #define ETRAX_FS_rw_pc_oe       56
  23 #define ETRAX_FS_rw_pd_dout     64
  24 #define ETRAX_FS_r_pd_din       68
  25 #define ETRAX_FS_rw_pd_oe       72
  26 #define ETRAX_FS_rw_pe_dout     80
  27 #define ETRAX_FS_r_pe_din       84
  28 #define ETRAX_FS_rw_pe_oe       88
  29
  30 #define ARTPEC3_r_pa_din        0
  31 #define ARTPEC3_rw_pa_dout      4
  32 #define ARTPEC3_rw_pa_oe        8
  33 #define ARTPEC3_r_pb_din        44
  34 #define ARTPEC3_rw_pb_dout      48
  35 #define ARTPEC3_rw_pb_oe        52
  36 #define ARTPEC3_r_pc_din        88
  37 #define ARTPEC3_rw_pc_dout      92
  38 #define ARTPEC3_rw_pc_oe        96
  39 #define ARTPEC3_r_pd_din        116
  40 #define ARTPEC3_rw_intr_cfg     120
  41 #define ARTPEC3_rw_intr_pins    124
  42 #define ARTPEC3_rw_intr_mask    128
  43 #define ARTPEC3_rw_ack_intr     132
  44 #define ARTPEC3_r_masked_intr   140
  45
  46 #define GIO_CFG_OFF             0
  47 #define GIO_CFG_HI              1
  48 #define GIO_CFG_LO              2
  49 #define GIO_CFG_SET             3
  50 #define GIO_CFG_POSEDGE         5
  51 #define GIO_CFG_NEGEDGE         6
  52 #define GIO_CFG_ANYEDGE         7
  53
  54 struct etraxfs_gpio_info;
  55
  56 struct etraxfs_gpio_block {
  57         spinlock_t lock;
  58         u32 mask;
  59         u32 cfg;
  60         u32 pins;
  61         unsigned int group[8];
  62
  63         void __iomem *regs;
  64         const struct etraxfs_gpio_info *info;
  65 };
  66
  67 struct etraxfs_gpio_chip {
  68         struct gpio_chip gc;
  69         struct etraxfs_gpio_block *block;
  70 };
  71
  72 struct etraxfs_gpio_port {
  73         const char *label;
  74         unsigned int oe;
  75         unsigned int dout;
  76         unsigned int din;
  77         unsigned int ngpio;
  78 };
  79
  80 struct etraxfs_gpio_info {
  81         unsigned int num_ports;
  82         const struct etraxfs_gpio_port *ports;
  83
  84         unsigned int rw_ack_intr;
  85         unsigned int rw_intr_mask;
  86         unsigned int rw_intr_cfg;
  87         unsigned int rw_intr_pins;
  88         unsigned int r_masked_intr;
  89 };
  90
  91 static const struct etraxfs_gpio_port etraxfs_gpio_etraxfs_ports[] = {
  92         {
  93                 .label  = "A",
  94                 .ngpio  = 8,
  95                 .oe     = ETRAX_FS_rw_pa_oe,
  96                 .dout   = ETRAX_FS_rw_pa_dout,
  97                 .din    = ETRAX_FS_r_pa_din,
  98         },
  99         {
 100                 .label  = "B",
 101                 .ngpio  = 18,
 102                 .oe     = ETRAX_FS_rw_pb_oe,
 103                 .dout   = ETRAX_FS_rw_pb_dout,
 104                 .din    = ETRAX_FS_r_pb_din,
 105         },
 106         {
 107                 .label  = "C",
 108                 .ngpio  = 18,
 109                 .oe     = ETRAX_FS_rw_pc_oe,
 110                 .dout   = ETRAX_FS_rw_pc_dout,
 111                 .din    = ETRAX_FS_r_pc_din,
 112         },
 113         {
 114                 .label  = "D",
 115                 .ngpio  = 18,
 116                 .oe     = ETRAX_FS_rw_pd_oe,
 117                 .dout   = ETRAX_FS_rw_pd_dout,
 118                 .din    = ETRAX_FS_r_pd_din,
 119         },
 120         {
 121                 .label  = "E",
 122                 .ngpio  = 18,
 123                 .oe     = ETRAX_FS_rw_pe_oe,
 124                 .dout   = ETRAX_FS_rw_pe_dout,
 125                 .din    = ETRAX_FS_r_pe_din,
 126         },
 127 };
 128
 129 static const struct etraxfs_gpio_info etraxfs_gpio_etraxfs = {
 130         .num_ports = ARRAY_SIZE(etraxfs_gpio_etraxfs_ports),
 131         .ports = etraxfs_gpio_etraxfs_ports,
 132         .rw_ack_intr    = ETRAX_FS_rw_ack_intr,
 133         .rw_intr_mask   = ETRAX_FS_rw_intr_mask,
 134         .rw_intr_cfg    = ETRAX_FS_rw_intr_cfg,
 135         .r_masked_intr  = ETRAX_FS_r_masked_intr,
 136 };
 137
 138 static const struct etraxfs_gpio_port etraxfs_gpio_artpec3_ports[] = {
 139         {
 140                 .label  = "A",
 141                 .ngpio  = 32,
 142                 .oe     = ARTPEC3_rw_pa_oe,
 143                 .dout   = ARTPEC3_rw_pa_dout,
 144                 .din    = ARTPEC3_r_pa_din,
 145         },
 146         {
 147                 .label  = "B",
 148                 .ngpio  = 32,
 149                 .oe     = ARTPEC3_rw_pb_oe,
 150                 .dout   = ARTPEC3_rw_pb_dout,
 151                 .din    = ARTPEC3_r_pb_din,
 152         },
 153         {
 154                 .label  = "C",
 155                 .ngpio  = 16,
 156                 .oe     = ARTPEC3_rw_pc_oe,
 157                 .dout   = ARTPEC3_rw_pc_dout,
 158                 .din    = ARTPEC3_r_pc_din,
 159         },
 160         {
 161                 .label  = "D",
 162                 .ngpio  = 32,
 163                 .din    = ARTPEC3_r_pd_din,
 164         },
 165 };
 166
 167 static const struct etraxfs_gpio_info etraxfs_gpio_artpec3 = {
 168         .num_ports = ARRAY_SIZE(etraxfs_gpio_artpec3_ports),
 169         .ports = etraxfs_gpio_artpec3_ports,
 170         .rw_ack_intr    = ARTPEC3_rw_ack_intr,
 171         .rw_intr_mask   = ARTPEC3_rw_intr_mask,
 172         .rw_intr_cfg    = ARTPEC3_rw_intr_cfg,
 173         .r_masked_intr  = ARTPEC3_r_masked_intr,
 174         .rw_intr_pins   = ARTPEC3_rw_intr_pins,
 175 };
 176
 177 static unsigned int etraxfs_gpio_chip_to_port(struct gpio_chip *gc)
 178 {
 179         return gc->label[0] - 'A';
 180 }
 181
 182 static int etraxfs_gpio_of_xlate(struct gpio_chip *gc,
 183                                const struct of_phandle_args *gpiospec,
 184                                u32 *flags)
 185 {
 186         /*
 187          * Port numbers are A to E, and the properties are integers, so we
 188          * specify them as 0xA - 0xE.
 189          */
 190         if (etraxfs_gpio_chip_to_port(gc) + 0xA != gpiospec->args[2])
 191                 return -EINVAL;
 192
 193         return of_gpio_simple_xlate(gc, gpiospec, flags);
 194 }
 195
 196 static const struct of_device_id etraxfs_gpio_of_table[] = {
 197         {
 198                 .compatible = "axis,etraxfs-gio",
 199                 .data = &etraxfs_gpio_etraxfs,
 200         },
 201         {
 202                 .compatible = "axis,artpec3-gio",
 203                 .data = &etraxfs_gpio_artpec3,
 204         },
 205         {},
 206 };
 207
 208 static unsigned int etraxfs_gpio_to_group_irq(unsigned int gpio)
 209 {
 210         return gpio % 8;
 211 }
 212
 213 static unsigned int etraxfs_gpio_to_group_pin(struct etraxfs_gpio_chip *chip,
 214                                               unsigned int gpio)
 215 {
 216         return 4 * etraxfs_gpio_chip_to_port(&chip->gc) + gpio / 8;
 217 }
 218
 219 static void etraxfs_gpio_irq_ack(struct irq_data *d)
 220 {
 221         struct etraxfs_gpio_chip *chip =
 222                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 223         struct etraxfs_gpio_block *block = chip->block;
 224         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 225
 226         writel(BIT(grpirq), block->regs + block->info->rw_ack_intr);
 227 }
 228
 229 static void etraxfs_gpio_irq_mask(struct irq_data *d)
 230 {
 231         struct etraxfs_gpio_chip *chip =
 232                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 233         struct etraxfs_gpio_block *block = chip->block;
 234         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 235
 236         spin_lock(&block->lock);
 237         block->mask &= ~BIT(grpirq);
 238         writel(block->mask, block->regs + block->info->rw_intr_mask);
 239         spin_unlock(&block->lock);
 240 }
 241
 242 static void etraxfs_gpio_irq_unmask(struct irq_data *d)
 243 {
 244         struct etraxfs_gpio_chip *chip =
 245                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 246         struct etraxfs_gpio_block *block = chip->block;
 247         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 248
 249         spin_lock(&block->lock);
 250         block->mask |= BIT(grpirq);
 251         writel(block->mask, block->regs + block->info->rw_intr_mask);
 252         spin_unlock(&block->lock);
 253 }
 254
 255 static int etraxfs_gpio_irq_set_type(struct irq_data *d, u32 type)
 256 {
 257         struct etraxfs_gpio_chip *chip =
 258                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 259         struct etraxfs_gpio_block *block = chip->block;
 260         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 261         u32 cfg;
 262
 263         switch (type) {
 264         case IRQ_TYPE_EDGE_RISING:
 265                 cfg = GIO_CFG_POSEDGE;
 266                 break;
 267         case IRQ_TYPE_EDGE_FALLING:
 268                 cfg = GIO_CFG_NEGEDGE;
 269                 break;
 270         case IRQ_TYPE_EDGE_BOTH:
 271                 cfg = GIO_CFG_ANYEDGE;
 272                 break;
 273         case IRQ_TYPE_LEVEL_LOW:
 274                 cfg = GIO_CFG_LO;
 275                 break;
 276         case IRQ_TYPE_LEVEL_HIGH:
 277                 cfg = GIO_CFG_HI;
 278                 break;
 279         default:
 280                 return -EINVAL;
 281         }
 282
 283         spin_lock(&block->lock);
 284         block->cfg &= ~(0x7 << (grpirq * 3));
 285         block->cfg |= (cfg << (grpirq * 3));
 286         writel(block->cfg, block->regs + block->info->rw_intr_cfg);
 287         spin_unlock(&block->lock);
 288
 289         return 0;
 290 }
 291
 292 static int etraxfs_gpio_irq_request_resources(struct irq_data *d)
 293 {
 294         struct etraxfs_gpio_chip *chip =
 295                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 296         struct etraxfs_gpio_block *block = chip->block;
 297         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 298         int ret = -EBUSY;
 299
 300         spin_lock(&block->lock);
 301         if (block->group[grpirq])
 302                 goto out;
 303
 304         ret = gpiochip_lock_as_irq(&chip->gc, d->hwirq);
 305         if (ret)
 306                 goto out;
 307
 308         block->group[grpirq] = d->irq;
 309         if (block->info->rw_intr_pins) {
 310                 unsigned int pin = etraxfs_gpio_to_group_pin(chip, d->hwirq);
 311
 312                 block->pins &= ~(0xf << (grpirq * 4));
 313                 block->pins |= (pin << (grpirq * 4));
 314
 315                 writel(block->pins, block->regs + block->info->rw_intr_pins);
 316         }
 317
 318 out:
 319         spin_unlock(&block->lock);
 320         return ret;
 321 }
 322
 323 static void etraxfs_gpio_irq_release_resources(struct irq_data *d)
 324 {
 325         struct etraxfs_gpio_chip *chip =
 326                 gpiochip_get_data(irq_data_get_irq_chip_data(d));
 327         struct etraxfs_gpio_block *block = chip->block;
 328         unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 329
 330         spin_lock(&block->lock);
 331         block->group[grpirq] = 0;
 332         gpiochip_unlock_as_irq(&chip->gc, d->hwirq);
 333         spin_unlock(&block->lock);
 334 }
 335
 336 static struct irq_chip etraxfs_gpio_irq_chip = {
 337         .name           = "gpio-etraxfs",
 338         .irq_ack        = etraxfs_gpio_irq_ack,
 339         .irq_mask       = etraxfs_gpio_irq_mask,
 340         .irq_unmask     = etraxfs_gpio_irq_unmask,
 341         .irq_set_type   = etraxfs_gpio_irq_set_type,
 342         .irq_request_resources = etraxfs_gpio_irq_request_resources,
 343         .irq_release_resources = etraxfs_gpio_irq_release_resources,
 344 };
 345
 346 static irqreturn_t etraxfs_gpio_interrupt(int irq, void *dev_id)
 347 {
 348         struct etraxfs_gpio_block *block = dev_id;
 349         unsigned long intr = readl(block->regs + block->info->r_masked_intr);
 350         int bit;
 351
 352         for_each_set_bit(bit, &intr, 8)
 353                 generic_handle_irq(block->group[bit]);
 354
 355         return IRQ_RETVAL(intr & 0xff);
 356 }
 357
 358 static int etraxfs_gpio_probe(struct platform_device *pdev)
 359 {
 360         struct device *dev = &pdev->dev;
 361         const struct etraxfs_gpio_info *info;
 362         const struct of_device_id *match;
 363         struct etraxfs_gpio_block *block;
 364         struct etraxfs_gpio_chip *chips;
 365         struct resource *res, *irq;
 366         bool allportsirq = false;
 367         void __iomem *regs;
 368         int ret;
 369         int i;
 370
 371         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 372         regs = devm_ioremap_resource(dev, res);
 373         if (IS_ERR(regs))
 374                 return PTR_ERR(regs);
 375
 376         match = of_match_node(etraxfs_gpio_of_table, dev->of_node);
 377         if (!match)
 378                 return -EINVAL;
 379
 380         info = match->data;
 381
 382         chips = devm_kzalloc(dev, sizeof(*chips) * info->num_ports, GFP_KERNEL);
 383         if (!chips)
 384                 return -ENOMEM;
 385
 386         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 387         if (!irq)
 388                 return -EINVAL;
 389
 390         block = devm_kzalloc(dev, sizeof(*block), GFP_KERNEL);
 391         if (!block)
 392                 return -ENOMEM;
 393
 394         spin_lock_init(&block->lock);
 395
 396         block->regs = regs;
 397         block->info = info;
 398
 399         writel(0, block->regs + info->rw_intr_mask);
 400         writel(0, block->regs + info->rw_intr_cfg);
 401         if (info->rw_intr_pins) {
 402                 allportsirq = true;
 403                 writel(0, block->regs + info->rw_intr_pins);
 404         }
 405
 406         ret = devm_request_irq(dev, irq->start, etraxfs_gpio_interrupt,
 407                                IRQF_SHARED, dev_name(dev), block);
 408         if (ret) {
 409                 dev_err(dev, "Unable to request irq %d\n", ret);
 410                 return ret;
 411         }
 412
 413         for (i = 0; i < info->num_ports; i++) {
 414                 struct etraxfs_gpio_chip *chip = &chips[i];
 415                 struct gpio_chip *gc = &chip->gc;
 416                 const struct etraxfs_gpio_port *port = &info->ports[i];
 417                 unsigned long flags = BGPIOF_READ_OUTPUT_REG_SET;
 418                 void __iomem *dat = regs + port->din;
 419                 void __iomem *set = regs + port->dout;
 420                 void __iomem *dirout = regs + port->oe;
 421
 422                 chip->block = block;
 423
 424                 if (dirout == set) {
 425                         dirout = set = NULL;
 426                         flags = BGPIOF_NO_OUTPUT;
 427                 }
 428
 429                 ret = bgpio_init(gc, dev, 4,
 430                                  dat, set, NULL, dirout, NULL,
 431                                  flags);
 432                 if (ret) {
 433                         dev_err(dev, "Unable to init port %s\n",
 434                                 port->label);
 435                         continue;
 436                 }
 437
 438                 gc->ngpio = port->ngpio;
 439                 gc->label = port->label;
 440
 441                 gc->of_node = dev->of_node;
 442                 gc->of_gpio_n_cells = 3;
 443                 gc->of_xlate = etraxfs_gpio_of_xlate;
 444
 445                 ret = gpiochip_add_data(gc, chip);
 446                 if (ret) {
 447                         dev_err(dev, "Unable to register port %s\n",
 448                                 gc->label);
 449                         continue;
 450                 }
 451
 452                 if (i > 0 && !allportsirq)
 453                         continue;
 454
 455                 ret = gpiochip_irqchip_add(gc, &etraxfs_gpio_irq_chip, 0,
 456                                            handle_level_irq, IRQ_TYPE_NONE);
 457                 if (ret) {
 458                         dev_err(dev, "Unable to add irqchip to port %s\n",
 459                                 gc->label);
 460                 }
 461         }
 462
 463         return 0;
 464 }
 465
 466 static struct platform_driver etraxfs_gpio_driver = {
 467         .driver = {
 468                 .name           = "etraxfs-gpio",
 469                 .of_match_table = of_match_ptr(etraxfs_gpio_of_table),
 470         },
 471         .probe  = etraxfs_gpio_probe,
 472 };
 473
 474 builtin_platform_driver(etraxfs_gpio_driver);