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 const struct of_device_id vf610_gpio_dt_ids[] = { 64 { .compatible = "fsl,vf610-gpio" }, 65 { /* sentinel */ } 66 }; 67 68 static inline void vf610_gpio_writel(u32 val, void __iomem *reg) 69 { 70 writel_relaxed(val, reg); 71 } 72 73 static inline u32 vf610_gpio_readl(void __iomem *reg) 74 { 75 return readl_relaxed(reg); 76 } 77 78 static int vf610_gpio_request(struct gpio_chip *chip, unsigned offset) 79 { 80 return pinctrl_request_gpio(chip->base + offset); 81 } 82 83 static void vf610_gpio_free(struct gpio_chip *chip, unsigned offset) 84 { 85 pinctrl_free_gpio(chip->base + offset); 86 } 87 88 static int vf610_gpio_get(struct gpio_chip *gc, unsigned int gpio) 89 { 90 struct vf610_gpio_port *port = 91 container_of(gc, struct vf610_gpio_port, gc); 92 93 return !!(vf610_gpio_readl(port->gpio_base + GPIO_PDIR) & BIT(gpio)); 94 } 95 96 static void vf610_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val) 97 { 98 struct vf610_gpio_port *port = 99 container_of(gc, struct vf610_gpio_port, gc); 100 unsigned long mask = BIT(gpio); 101 102 if (val) 103 vf610_gpio_writel(mask, port->gpio_base + GPIO_PSOR); 104 else 105 vf610_gpio_writel(mask, port->gpio_base + GPIO_PCOR); 106 } 107 108 static int vf610_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) 109 { 110 return pinctrl_gpio_direction_input(chip->base + gpio); 111 } 112 113 static int vf610_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, 114 int value) 115 { 116 vf610_gpio_set(chip, gpio, value); 117 118 return pinctrl_gpio_direction_output(chip->base + gpio); 119 } 120 121 static void vf610_gpio_irq_handler(u32 irq, struct irq_desc *desc) 122 { 123 struct vf610_gpio_port *port = irq_get_handler_data(irq); 124 struct irq_chip *chip = irq_desc_get_chip(desc); 125 int pin; 126 unsigned long irq_isfr; 127 128 chained_irq_enter(chip, desc); 129 130 irq_isfr = vf610_gpio_readl(port->base + PORT_ISFR); 131 132 for_each_set_bit(pin, &irq_isfr, VF610_GPIO_PER_PORT) { 133 vf610_gpio_writel(BIT(pin), port->base + PORT_ISFR); 134 135 generic_handle_irq(irq_find_mapping(port->gc.irqdomain, pin)); 136 } 137 138 chained_irq_exit(chip, desc); 139 } 140 141 static void vf610_gpio_irq_ack(struct irq_data *d) 142 { 143 struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); 144 int gpio = d->hwirq; 145 146 vf610_gpio_writel(BIT(gpio), port->base + PORT_ISFR); 147 } 148 149 static int vf610_gpio_irq_set_type(struct irq_data *d, u32 type) 150 { 151 struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); 152 u8 irqc; 153 154 switch (type) { 155 case IRQ_TYPE_EDGE_RISING: 156 irqc = PORT_INT_RISING_EDGE; 157 break; 158 case IRQ_TYPE_EDGE_FALLING: 159 irqc = PORT_INT_FALLING_EDGE; 160 break; 161 case IRQ_TYPE_EDGE_BOTH: 162 irqc = PORT_INT_EITHER_EDGE; 163 break; 164 case IRQ_TYPE_LEVEL_LOW: 165 irqc = PORT_INT_LOGIC_ZERO; 166 break; 167 case IRQ_TYPE_LEVEL_HIGH: 168 irqc = PORT_INT_LOGIC_ONE; 169 break; 170 default: 171 return -EINVAL; 172 } 173 174 port->irqc[d->hwirq] = irqc; 175 176 return 0; 177 } 178 179 static void vf610_gpio_irq_mask(struct irq_data *d) 180 { 181 struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); 182 void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq); 183 184 vf610_gpio_writel(0, pcr_base); 185 } 186 187 static void vf610_gpio_irq_unmask(struct irq_data *d) 188 { 189 struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); 190 void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq); 191 192 vf610_gpio_writel(port->irqc[d->hwirq] << PORT_PCR_IRQC_OFFSET, 193 pcr_base); 194 } 195 196 static int vf610_gpio_irq_set_wake(struct irq_data *d, u32 enable) 197 { 198 struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); 199 200 if (enable) 201 enable_irq_wake(port->irq); 202 else 203 disable_irq_wake(port->irq); 204 205 return 0; 206 } 207 208 static struct irq_chip vf610_gpio_irq_chip = { 209 .name = "gpio-vf610", 210 .irq_ack = vf610_gpio_irq_ack, 211 .irq_mask = vf610_gpio_irq_mask, 212 .irq_unmask = vf610_gpio_irq_unmask, 213 .irq_set_type = vf610_gpio_irq_set_type, 214 .irq_set_wake = vf610_gpio_irq_set_wake, 215 }; 216 217 static int vf610_gpio_probe(struct platform_device *pdev) 218 { 219 struct device *dev = &pdev->dev; 220 struct device_node *np = dev->of_node; 221 struct vf610_gpio_port *port; 222 struct resource *iores; 223 struct gpio_chip *gc; 224 int ret; 225 226 port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); 227 if (!port) 228 return -ENOMEM; 229 230 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); 231 port->base = devm_ioremap_resource(dev, iores); 232 if (IS_ERR(port->base)) 233 return PTR_ERR(port->base); 234 235 iores = platform_get_resource(pdev, IORESOURCE_MEM, 1); 236 port->gpio_base = devm_ioremap_resource(dev, iores); 237 if (IS_ERR(port->gpio_base)) 238 return PTR_ERR(port->gpio_base); 239 240 port->irq = platform_get_irq(pdev, 0); 241 if (port->irq < 0) 242 return port->irq; 243 244 gc = &port->gc; 245 gc->of_node = np; 246 gc->dev = dev; 247 gc->label = "vf610-gpio"; 248 gc->ngpio = VF610_GPIO_PER_PORT; 249 gc->base = of_alias_get_id(np, "gpio") * VF610_GPIO_PER_PORT; 250 251 gc->request = vf610_gpio_request; 252 gc->free = vf610_gpio_free; 253 gc->direction_input = vf610_gpio_direction_input; 254 gc->get = vf610_gpio_get; 255 gc->direction_output = vf610_gpio_direction_output; 256 gc->set = vf610_gpio_set; 257 258 ret = gpiochip_add(gc); 259 if (ret < 0) 260 return ret; 261 262 /* Clear the interrupt status register for all GPIO's */ 263 vf610_gpio_writel(~0, port->base + PORT_ISFR); 264 265 ret = gpiochip_irqchip_add(gc, &vf610_gpio_irq_chip, 0, 266 handle_simple_irq, IRQ_TYPE_NONE); 267 if (ret) { 268 dev_err(dev, "failed to add irqchip\n"); 269 gpiochip_remove(gc); 270 return ret; 271 } 272 gpiochip_set_chained_irqchip(gc, &vf610_gpio_irq_chip, port->irq, 273 vf610_gpio_irq_handler); 274 275 return 0; 276 } 277 278 static struct platform_driver vf610_gpio_driver = { 279 .driver = { 280 .name = "gpio-vf610", 281 .of_match_table = vf610_gpio_dt_ids, 282 }, 283 .probe = vf610_gpio_probe, 284 }; 285 286 static int __init gpio_vf610_init(void) 287 { 288 return platform_driver_register(&vf610_gpio_driver); 289 } 290 device_initcall(gpio_vf610_init); 291 292 MODULE_AUTHOR("Stefan Agner <stefan@agner.ch>"); 293 MODULE_DESCRIPTION("Freescale VF610 GPIO"); 294 MODULE_LICENSE("GPL v2"); 295