drivers/gpio/gpio-xgene-sb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * AppliedMicro X-Gene SoC GPIO-Standby Driver
   4  *
   5  * Copyright (c) 2014, Applied Micro Circuits Corporation
   6  * Author:      Tin Huynh <tnhuynh@apm.com>.
   7  *              Y Vo <yvo@apm.com>.
   8  *              Quan Nguyen <qnguyen@apm.com>.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/io.h>
  13 #include <linux/of.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/gpio/driver.h>
  16 #include <linux/acpi.h>
  17
  18 #include "gpiolib-acpi.h"
  19
  20 /* Common property names */
  21 #define XGENE_NIRQ_PROPERTY             "apm,nr-irqs"
  22 #define XGENE_NGPIO_PROPERTY            "apm,nr-gpios"
  23 #define XGENE_IRQ_START_PROPERTY        "apm,irq-start"
  24
  25 #define XGENE_DFLT_MAX_NGPIO            22
  26 #define XGENE_DFLT_MAX_NIRQ             6
  27 #define XGENE_DFLT_IRQ_START_PIN        8
  28 #define GPIO_MASK(x)                    (1U << ((x) % 32))
  29
  30 #define MPA_GPIO_INT_LVL                0x0290
  31 #define MPA_GPIO_OE_ADDR                0x029c
  32 #define MPA_GPIO_OUT_ADDR               0x02a0
  33 #define MPA_GPIO_IN_ADDR                0x02a4
  34 #define MPA_GPIO_SEL_LO                 0x0294
  35
  36 #define GPIO_INT_LEVEL_H        0x000001
  37 #define GPIO_INT_LEVEL_L        0x000000
  38
  39 /**
  40  * struct xgene_gpio_sb - GPIO-Standby private data structure.
  41  * @gc:                         memory-mapped GPIO controllers.
  42  * @regs:                       GPIO register base offset
  43  * @irq_domain:                 GPIO interrupt domain
  44  * @irq_start:                  GPIO pin that start support interrupt
  45  * @nirq:                       Number of GPIO pins that supports interrupt
  46  * @parent_irq_base:            Start parent HWIRQ
  47  */
  48 struct xgene_gpio_sb {
  49         struct gpio_chip        gc;
  50         void __iomem            *regs;
  51         struct irq_domain       *irq_domain;
  52         u16                     irq_start;
  53         u16                     nirq;
  54         u16                     parent_irq_base;
  55 };
  56
  57 #define HWIRQ_TO_GPIO(priv, hwirq) ((hwirq) + (priv)->irq_start)
  58 #define GPIO_TO_HWIRQ(priv, gpio) ((gpio) - (priv)->irq_start)
  59
  60 static void xgene_gpio_set_bit(struct gpio_chip *gc,
  61                                 void __iomem *reg, u32 gpio, int val)
  62 {
  63         u32 data;
  64
  65         data = gc->read_reg(reg);
  66         if (val)
  67                 data |= GPIO_MASK(gpio);
  68         else
  69                 data &= ~GPIO_MASK(gpio);
  70         gc->write_reg(reg, data);
  71 }
  72
  73 static int xgene_gpio_sb_irq_set_type(struct irq_data *d, unsigned int type)
  74 {
  75         struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
  76         int gpio = HWIRQ_TO_GPIO(priv, d->hwirq);
  77         int lvl_type = GPIO_INT_LEVEL_H;
  78
  79         switch (type & IRQ_TYPE_SENSE_MASK) {
  80         case IRQ_TYPE_EDGE_RISING:
  81         case IRQ_TYPE_LEVEL_HIGH:
  82                 lvl_type = GPIO_INT_LEVEL_H;
  83                 break;
  84         case IRQ_TYPE_EDGE_FALLING:
  85         case IRQ_TYPE_LEVEL_LOW:
  86                 lvl_type = GPIO_INT_LEVEL_L;
  87                 break;
  88         default:
  89                 break;
  90         }
  91
  92         xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
  93                         gpio * 2, 1);
  94         xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_INT_LVL,
  95                         d->hwirq, lvl_type);
  96
  97         /* Propagate IRQ type setting to parent */
  98         if (type & IRQ_TYPE_EDGE_BOTH)
  99                 return irq_chip_set_type_parent(d, IRQ_TYPE_EDGE_RISING);
 100         else
 101                 return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
 102 }
 103
 104 static struct irq_chip xgene_gpio_sb_irq_chip = {
 105         .name           = "sbgpio",
 106         .irq_eoi        = irq_chip_eoi_parent,
 107         .irq_mask       = irq_chip_mask_parent,
 108         .irq_unmask     = irq_chip_unmask_parent,
 109         .irq_set_type   = xgene_gpio_sb_irq_set_type,
 110 };
 111
 112 static int xgene_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
 113 {
 114         struct xgene_gpio_sb *priv = gpiochip_get_data(gc);
 115         struct irq_fwspec fwspec;
 116
 117         if ((gpio < priv->irq_start) ||
 118                         (gpio > HWIRQ_TO_GPIO(priv, priv->nirq)))
 119                 return -ENXIO;
 120
 121         fwspec.fwnode = gc->parent->fwnode;
 122         fwspec.param_count = 2;
 123         fwspec.param[0] = GPIO_TO_HWIRQ(priv, gpio);
 124         fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
 125         return irq_create_fwspec_mapping(&fwspec);
 126 }
 127
 128 static int xgene_gpio_sb_domain_activate(struct irq_domain *d,
 129                                          struct irq_data *irq_data,
 130                                          bool reserve)
 131 {
 132         struct xgene_gpio_sb *priv = d->host_data;
 133         u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
 134         int ret;
 135
 136         ret = gpiochip_lock_as_irq(&priv->gc, gpio);
 137         if (ret) {
 138                 dev_err(priv->gc.parent,
 139                 "Unable to configure XGene GPIO standby pin %d as IRQ\n",
 140                                 gpio);
 141                 return ret;
 142         }
 143
 144         xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
 145                         gpio * 2, 1);
 146         return 0;
 147 }
 148
 149 static void xgene_gpio_sb_domain_deactivate(struct irq_domain *d,
 150                 struct irq_data *irq_data)
 151 {
 152         struct xgene_gpio_sb *priv = d->host_data;
 153         u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
 154
 155         gpiochip_unlock_as_irq(&priv->gc, gpio);
 156         xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
 157                         gpio * 2, 0);
 158 }
 159
 160 static int xgene_gpio_sb_domain_translate(struct irq_domain *d,
 161                 struct irq_fwspec *fwspec,
 162                 unsigned long *hwirq,
 163                 unsigned int *type)
 164 {
 165         struct xgene_gpio_sb *priv = d->host_data;
 166
 167         if ((fwspec->param_count != 2) ||
 168                 (fwspec->param[0] >= priv->nirq))
 169                 return -EINVAL;
 170         *hwirq = fwspec->param[0];
 171         *type = fwspec->param[1];
 172         return 0;
 173 }
 174
 175 static int xgene_gpio_sb_domain_alloc(struct irq_domain *domain,
 176                                         unsigned int virq,
 177                                         unsigned int nr_irqs, void *data)
 178 {
 179         struct irq_fwspec *fwspec = data;
 180         struct irq_fwspec parent_fwspec;
 181         struct xgene_gpio_sb *priv = domain->host_data;
 182         irq_hw_number_t hwirq;
 183         unsigned int i;
 184
 185         hwirq = fwspec->param[0];
 186         for (i = 0; i < nr_irqs; i++)
 187                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 188                                 &xgene_gpio_sb_irq_chip, priv);
 189
 190         parent_fwspec.fwnode = domain->parent->fwnode;
 191         if (is_of_node(parent_fwspec.fwnode)) {
 192                 parent_fwspec.param_count = 3;
 193                 parent_fwspec.param[0] = 0;/* SPI */
 194                 /* Skip SGIs and PPIs*/
 195                 parent_fwspec.param[1] = hwirq + priv->parent_irq_base - 32;
 196                 parent_fwspec.param[2] = fwspec->param[1];
 197         } else if (is_fwnode_irqchip(parent_fwspec.fwnode)) {
 198                 parent_fwspec.param_count = 2;
 199                 parent_fwspec.param[0] = hwirq + priv->parent_irq_base;
 200                 parent_fwspec.param[1] = fwspec->param[1];
 201         } else
 202                 return -EINVAL;
 203
 204         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
 205                         &parent_fwspec);
 206 }
 207
 208 static const struct irq_domain_ops xgene_gpio_sb_domain_ops = {
 209         .translate      = xgene_gpio_sb_domain_translate,
 210         .alloc          = xgene_gpio_sb_domain_alloc,
 211         .free           = irq_domain_free_irqs_common,
 212         .activate       = xgene_gpio_sb_domain_activate,
 213         .deactivate     = xgene_gpio_sb_domain_deactivate,
 214 };
 215
 216 static int xgene_gpio_sb_probe(struct platform_device *pdev)
 217 {
 218         struct xgene_gpio_sb *priv;
 219         int ret;
 220         void __iomem *regs;
 221         struct irq_domain *parent_domain = NULL;
 222         u32 val32;
 223
 224         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 225         if (!priv)
 226                 return -ENOMEM;
 227
 228         regs = devm_platform_ioremap_resource(pdev, 0);
 229         if (IS_ERR(regs))
 230                 return PTR_ERR(regs);
 231
 232         priv->regs = regs;
 233
 234         ret = platform_get_irq(pdev, 0);
 235         if (ret > 0) {
 236                 priv->parent_irq_base = irq_get_irq_data(ret)->hwirq;
 237                 parent_domain = irq_get_irq_data(ret)->domain;
 238         }
 239         if (!parent_domain) {
 240                 dev_err(&pdev->dev, "unable to obtain parent domain\n");
 241                 return -ENODEV;
 242         }
 243
 244         ret = bgpio_init(&priv->gc, &pdev->dev, 4,
 245                         regs + MPA_GPIO_IN_ADDR,
 246                         regs + MPA_GPIO_OUT_ADDR, NULL,
 247                         regs + MPA_GPIO_OE_ADDR, NULL, 0);
 248         if (ret)
 249                 return ret;
 250
 251         priv->gc.to_irq = xgene_gpio_sb_to_irq;
 252
 253         /* Retrieve start irq pin, use default if property not found */
 254         priv->irq_start = XGENE_DFLT_IRQ_START_PIN;
 255         if (!device_property_read_u32(&pdev->dev,
 256                                         XGENE_IRQ_START_PROPERTY, &val32))
 257                 priv->irq_start = val32;
 258
 259         /* Retrieve number irqs, use default if property not found */
 260         priv->nirq = XGENE_DFLT_MAX_NIRQ;
 261         if (!device_property_read_u32(&pdev->dev, XGENE_NIRQ_PROPERTY, &val32))
 262                 priv->nirq = val32;
 263
 264         /* Retrieve number gpio, use default if property not found */
 265         priv->gc.ngpio = XGENE_DFLT_MAX_NGPIO;
 266         if (!device_property_read_u32(&pdev->dev, XGENE_NGPIO_PROPERTY, &val32))
 267                 priv->gc.ngpio = val32;
 268
 269         dev_info(&pdev->dev, "Support %d gpios, %d irqs start from pin %d\n",
 270                         priv->gc.ngpio, priv->nirq, priv->irq_start);
 271
 272         platform_set_drvdata(pdev, priv);
 273
 274         priv->irq_domain = irq_domain_create_hierarchy(parent_domain,
 275                                         0, priv->nirq, pdev->dev.fwnode,
 276                                         &xgene_gpio_sb_domain_ops, priv);
 277         if (!priv->irq_domain)
 278                 return -ENODEV;
 279
 280         priv->gc.irq.domain = priv->irq_domain;
 281
 282         ret = devm_gpiochip_add_data(&pdev->dev, &priv->gc, priv);
 283         if (ret) {
 284                 dev_err(&pdev->dev,
 285                         "failed to register X-Gene GPIO Standby driver\n");
 286                 irq_domain_remove(priv->irq_domain);
 287                 return ret;
 288         }
 289
 290         dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n");
 291
 292         /* Register interrupt handlers for GPIO signaled ACPI Events */
 293         acpi_gpiochip_request_interrupts(&priv->gc);
 294
 295         return ret;
 296 }
 297
 298 static void xgene_gpio_sb_remove(struct platform_device *pdev)
 299 {
 300         struct xgene_gpio_sb *priv = platform_get_drvdata(pdev);
 301
 302         acpi_gpiochip_free_interrupts(&priv->gc);
 303
 304         irq_domain_remove(priv->irq_domain);
 305 }
 306
 307 static const struct of_device_id xgene_gpio_sb_of_match[] = {
 308         {.compatible = "apm,xgene-gpio-sb", },
 309         {},
 310 };
 311 MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match);
 312
 313 #ifdef CONFIG_ACPI
 314 static const struct acpi_device_id xgene_gpio_sb_acpi_match[] = {
 315         {"APMC0D15", 0},
 316         {},
 317 };
 318 MODULE_DEVICE_TABLE(acpi, xgene_gpio_sb_acpi_match);
 319 #endif
 320
 321 static struct platform_driver xgene_gpio_sb_driver = {
 322         .driver = {
 323                    .name = "xgene-gpio-sb",
 324                    .of_match_table = xgene_gpio_sb_of_match,
 325                    .acpi_match_table = ACPI_PTR(xgene_gpio_sb_acpi_match),
 326                    },
 327         .probe = xgene_gpio_sb_probe,
 328         .remove_new = xgene_gpio_sb_remove,
 329 };
 330 module_platform_driver(xgene_gpio_sb_driver);
 331
 332 MODULE_AUTHOR("AppliedMicro");
 333 MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver");
 334 MODULE_LICENSE("GPL");