drivers/gpio/gpio-vf610.c

   1 /*
   2  * vf610 GPIO support through PORT and GPIO module
   3  *
   4  * Copyright (c) 2014 Toradex AG.
   5  *
   6  * Author: Stefan Agner <stefan@agner.ch>.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version 2
  11  * of the License, or (at your option) any later version.
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/bitops.h>
  19 #include <linux/err.h>
  20 #include <linux/gpio.h>
  21 #include <linux/init.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/io.h>
  24 #include <linux/ioport.h>
  25 #include <linux/irq.h>
  26 #include <linux/module.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/of.h>
  29 #include <linux/of_device.h>
  30 #include <linux/of_irq.h>
  31
  32 #define VF610_GPIO_PER_PORT             32
  33
  34 struct vf610_gpio_port {
  35         struct gpio_chip gc;
  36         void __iomem *base;
  37         void __iomem *gpio_base;
  38         u8 irqc[VF610_GPIO_PER_PORT];
  39         int irq;
  40 };
  41
  42 #define GPIO_PDOR               0x00
  43 #define GPIO_PSOR               0x04
  44 #define GPIO_PCOR               0x08
  45 #define GPIO_PTOR               0x0c
  46 #define GPIO_PDIR               0x10
  47
  48 #define PORT_PCR(n)             ((n) * 0x4)
  49 #define PORT_PCR_IRQC_OFFSET    16
  50
  51 #define PORT_ISFR               0xa0
  52 #define PORT_DFER               0xc0
  53 #define PORT_DFCR               0xc4
  54 #define PORT_DFWR               0xc8
  55
  56 #define PORT_INT_OFF            0x0
  57 #define PORT_INT_LOGIC_ZERO     0x8
  58 #define PORT_INT_RISING_EDGE    0x9
  59 #define PORT_INT_FALLING_EDGE   0xa
  60 #define PORT_INT_EITHER_EDGE    0xb
  61 #define PORT_INT_LOGIC_ONE      0xc
  62
  63 static struct irq_chip vf610_gpio_irq_chip;
  64
  65 static struct vf610_gpio_port *to_vf610_gp(struct gpio_chip *gc)
  66 {
  67         return container_of(gc, struct vf610_gpio_port, gc);
  68 }
  69
  70 static const struct of_device_id vf610_gpio_dt_ids[] = {
  71         { .compatible = "fsl,vf610-gpio" },
  72         { /* sentinel */ }
  73 };
  74
  75 static inline void vf610_gpio_writel(u32 val, void __iomem *reg)
  76 {
  77         writel_relaxed(val, reg);
  78 }
  79
  80 static inline u32 vf610_gpio_readl(void __iomem *reg)
  81 {
  82         return readl_relaxed(reg);
  83 }
  84
  85 static int vf610_gpio_get(struct gpio_chip *gc, unsigned int gpio)
  86 {
  87         struct vf610_gpio_port *port = to_vf610_gp(gc);
  88
  89         return !!(vf610_gpio_readl(port->gpio_base + GPIO_PDIR) & BIT(gpio));
  90 }
  91
  92 static void vf610_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
  93 {
  94         struct vf610_gpio_port *port = to_vf610_gp(gc);
  95         unsigned long mask = BIT(gpio);
  96
  97         if (val)
  98                 vf610_gpio_writel(mask, port->gpio_base + GPIO_PSOR);
  99         else
 100                 vf610_gpio_writel(mask, port->gpio_base + GPIO_PCOR);
 101 }
 102
 103 static int vf610_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 104 {
 105         return pinctrl_gpio_direction_input(chip->base + gpio);
 106 }
 107
 108 static int vf610_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
 109                                        int value)
 110 {
 111         vf610_gpio_set(chip, gpio, value);
 112
 113         return pinctrl_gpio_direction_output(chip->base + gpio);
 114 }
 115
 116 static void vf610_gpio_irq_handler(struct irq_desc *desc)
 117 {
 118         struct vf610_gpio_port *port =
 119                 to_vf610_gp(irq_desc_get_handler_data(desc));
 120         struct irq_chip *chip = irq_desc_get_chip(desc);
 121         int pin;
 122         unsigned long irq_isfr;
 123
 124         chained_irq_enter(chip, desc);
 125
 126         irq_isfr = vf610_gpio_readl(port->base + PORT_ISFR);
 127
 128         for_each_set_bit(pin, &irq_isfr, VF610_GPIO_PER_PORT) {
 129                 vf610_gpio_writel(BIT(pin), port->base + PORT_ISFR);
 130
 131                 generic_handle_irq(irq_find_mapping(port->gc.irqdomain, pin));
 132         }
 133
 134         chained_irq_exit(chip, desc);
 135 }
 136
 137 static void vf610_gpio_irq_ack(struct irq_data *d)
 138 {
 139         struct vf610_gpio_port *port =
 140                 to_vf610_gp(irq_data_get_irq_chip_data(d));
 141         int gpio = d->hwirq;
 142
 143         vf610_gpio_writel(BIT(gpio), port->base + PORT_ISFR);
 144 }
 145
 146 static int vf610_gpio_irq_set_type(struct irq_data *d, u32 type)
 147 {
 148         struct vf610_gpio_port *port =
 149                 to_vf610_gp(irq_data_get_irq_chip_data(d));
 150         u8 irqc;
 151
 152         switch (type) {
 153         case IRQ_TYPE_EDGE_RISING:
 154                 irqc = PORT_INT_RISING_EDGE;
 155                 break;
 156         case IRQ_TYPE_EDGE_FALLING:
 157                 irqc = PORT_INT_FALLING_EDGE;
 158                 break;
 159         case IRQ_TYPE_EDGE_BOTH:
 160                 irqc = PORT_INT_EITHER_EDGE;
 161                 break;
 162         case IRQ_TYPE_LEVEL_LOW:
 163                 irqc = PORT_INT_LOGIC_ZERO;
 164                 break;
 165         case IRQ_TYPE_LEVEL_HIGH:
 166                 irqc = PORT_INT_LOGIC_ONE;
 167                 break;
 168         default:
 169                 return -EINVAL;
 170         }
 171
 172         port->irqc[d->hwirq] = irqc;
 173
 174         if (type & IRQ_TYPE_LEVEL_MASK)
 175                 irq_set_handler_locked(d, handle_level_irq);
 176         else
 177                 irq_set_handler_locked(d, handle_edge_irq);
 178
 179         return 0;
 180 }
 181
 182 static void vf610_gpio_irq_mask(struct irq_data *d)
 183 {
 184         struct vf610_gpio_port *port =
 185                 to_vf610_gp(irq_data_get_irq_chip_data(d));
 186         void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
 187
 188         vf610_gpio_writel(0, pcr_base);
 189 }
 190
 191 static void vf610_gpio_irq_unmask(struct irq_data *d)
 192 {
 193         struct vf610_gpio_port *port =
 194                 to_vf610_gp(irq_data_get_irq_chip_data(d));
 195         void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
 196
 197         vf610_gpio_writel(port->irqc[d->hwirq] << PORT_PCR_IRQC_OFFSET,
 198                           pcr_base);
 199 }
 200
 201 static int vf610_gpio_irq_set_wake(struct irq_data *d, u32 enable)
 202 {
 203         struct vf610_gpio_port *port =
 204                 to_vf610_gp(irq_data_get_irq_chip_data(d));
 205
 206         if (enable)
 207                 enable_irq_wake(port->irq);
 208         else
 209                 disable_irq_wake(port->irq);
 210
 211         return 0;
 212 }
 213
 214 static struct irq_chip vf610_gpio_irq_chip = {
 215         .name           = "gpio-vf610",
 216         .irq_ack        = vf610_gpio_irq_ack,
 217         .irq_mask       = vf610_gpio_irq_mask,
 218         .irq_unmask     = vf610_gpio_irq_unmask,
 219         .irq_set_type   = vf610_gpio_irq_set_type,
 220         .irq_set_wake   = vf610_gpio_irq_set_wake,
 221 };
 222
 223 static int vf610_gpio_probe(struct platform_device *pdev)
 224 {
 225         struct device *dev = &pdev->dev;
 226         struct device_node *np = dev->of_node;
 227         struct vf610_gpio_port *port;
 228         struct resource *iores;
 229         struct gpio_chip *gc;
 230         int ret;
 231
 232         port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
 233         if (!port)
 234                 return -ENOMEM;
 235
 236         iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 237         port->base = devm_ioremap_resource(dev, iores);
 238         if (IS_ERR(port->base))
 239                 return PTR_ERR(port->base);
 240
 241         iores = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 242         port->gpio_base = devm_ioremap_resource(dev, iores);
 243         if (IS_ERR(port->gpio_base))
 244                 return PTR_ERR(port->gpio_base);
 245
 246         port->irq = platform_get_irq(pdev, 0);
 247         if (port->irq < 0)
 248                 return port->irq;
 249
 250         gc = &port->gc;
 251         gc->of_node = np;
 252         gc->dev = dev;
 253         gc->label = "vf610-gpio";
 254         gc->ngpio = VF610_GPIO_PER_PORT;
 255         gc->base = of_alias_get_id(np, "gpio") * VF610_GPIO_PER_PORT;
 256
 257         gc->request = gpiochip_generic_request;
 258         gc->free = gpiochip_generic_free;
 259         gc->direction_input = vf610_gpio_direction_input;
 260         gc->get = vf610_gpio_get;
 261         gc->direction_output = vf610_gpio_direction_output;
 262         gc->set = vf610_gpio_set;
 263
 264         ret = gpiochip_add(gc);
 265         if (ret < 0)
 266                 return ret;
 267
 268         /* Clear the interrupt status register for all GPIO's */
 269         vf610_gpio_writel(~0, port->base + PORT_ISFR);
 270
 271         ret = gpiochip_irqchip_add(gc, &vf610_gpio_irq_chip, 0,
 272                                    handle_edge_irq, IRQ_TYPE_NONE);
 273         if (ret) {
 274                 dev_err(dev, "failed to add irqchip\n");
 275                 gpiochip_remove(gc);
 276                 return ret;
 277         }
 278         gpiochip_set_chained_irqchip(gc, &vf610_gpio_irq_chip, port->irq,
 279                                      vf610_gpio_irq_handler);
 280
 281         return 0;
 282 }
 283
 284 static struct platform_driver vf610_gpio_driver = {
 285         .driver         = {
 286                 .name   = "gpio-vf610",
 287                 .of_match_table = vf610_gpio_dt_ids,
 288         },
 289         .probe          = vf610_gpio_probe,
 290 };
 291
 292 static int __init gpio_vf610_init(void)
 293 {
 294         return platform_driver_register(&vf610_gpio_driver);
 295 }
 296 device_initcall(gpio_vf610_init);
 297
 298 MODULE_AUTHOR("Stefan Agner <stefan@agner.ch>");
 299 MODULE_DESCRIPTION("Freescale VF610 GPIO");
 300 MODULE_LICENSE("GPL v2");