1 /* 2 * Broadcom specific AMBA 3 * GPIO driver 4 * 5 * Copyright 2011, Broadcom Corporation 6 * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de> 7 * 8 * Licensed under the GNU/GPL. See COPYING for details. 9 */ 10 11 #include <linux/gpio.h> 12 #include <linux/irq.h> 13 #include <linux/interrupt.h> 14 #include <linux/irqdomain.h> 15 #include <linux/export.h> 16 #include <linux/bcma/bcma.h> 17 18 #include "bcma_private.h" 19 20 #define BCMA_GPIO_MAX_PINS 32 21 22 static inline struct bcma_drv_cc *bcma_gpio_get_cc(struct gpio_chip *chip) 23 { 24 return container_of(chip, struct bcma_drv_cc, gpio); 25 } 26 27 static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio) 28 { 29 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 30 31 return !!bcma_chipco_gpio_in(cc, 1 << gpio); 32 } 33 34 static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio, 35 int value) 36 { 37 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 38 39 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 40 } 41 42 static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) 43 { 44 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 45 46 bcma_chipco_gpio_outen(cc, 1 << gpio, 0); 47 return 0; 48 } 49 50 static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, 51 int value) 52 { 53 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 54 55 bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio); 56 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 57 return 0; 58 } 59 60 static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio) 61 { 62 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 63 64 bcma_chipco_gpio_control(cc, 1 << gpio, 0); 65 /* clear pulldown */ 66 bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0); 67 /* Set pullup */ 68 bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio); 69 70 return 0; 71 } 72 73 static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio) 74 { 75 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 76 77 /* clear pullup */ 78 bcma_chipco_gpio_pullup(cc, 1 << gpio, 0); 79 } 80 81 #if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X) 82 static int bcma_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) 83 { 84 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 85 86 if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 87 return irq_find_mapping(cc->irq_domain, gpio); 88 else 89 return -EINVAL; 90 } 91 92 static void bcma_gpio_irq_unmask(struct irq_data *d) 93 { 94 struct bcma_drv_cc *cc = irq_data_get_irq_chip_data(d); 95 int gpio = irqd_to_hwirq(d); 96 u32 val = bcma_chipco_gpio_in(cc, BIT(gpio)); 97 98 bcma_chipco_gpio_polarity(cc, BIT(gpio), val); 99 bcma_chipco_gpio_intmask(cc, BIT(gpio), BIT(gpio)); 100 } 101 102 static void bcma_gpio_irq_mask(struct irq_data *d) 103 { 104 struct bcma_drv_cc *cc = irq_data_get_irq_chip_data(d); 105 int gpio = irqd_to_hwirq(d); 106 107 bcma_chipco_gpio_intmask(cc, BIT(gpio), 0); 108 } 109 110 static struct irq_chip bcma_gpio_irq_chip = { 111 .name = "BCMA-GPIO", 112 .irq_mask = bcma_gpio_irq_mask, 113 .irq_unmask = bcma_gpio_irq_unmask, 114 }; 115 116 static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id) 117 { 118 struct bcma_drv_cc *cc = dev_id; 119 u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN); 120 u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ); 121 u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL); 122 unsigned long irqs = (val ^ pol) & mask; 123 int gpio; 124 125 if (!irqs) 126 return IRQ_NONE; 127 128 for_each_set_bit(gpio, &irqs, cc->gpio.ngpio) 129 generic_handle_irq(bcma_gpio_to_irq(&cc->gpio, gpio)); 130 bcma_chipco_gpio_polarity(cc, irqs, val & irqs); 131 132 return IRQ_HANDLED; 133 } 134 135 static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc) 136 { 137 struct gpio_chip *chip = &cc->gpio; 138 int gpio, hwirq, err; 139 140 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) 141 return 0; 142 143 cc->irq_domain = irq_domain_add_linear(NULL, chip->ngpio, 144 &irq_domain_simple_ops, cc); 145 if (!cc->irq_domain) { 146 err = -ENODEV; 147 goto err_irq_domain; 148 } 149 for (gpio = 0; gpio < chip->ngpio; gpio++) { 150 int irq = irq_create_mapping(cc->irq_domain, gpio); 151 152 irq_set_chip_data(irq, cc); 153 irq_set_chip_and_handler(irq, &bcma_gpio_irq_chip, 154 handle_simple_irq); 155 } 156 157 hwirq = bcma_core_irq(cc->core, 0); 158 err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio", 159 cc); 160 if (err) 161 goto err_req_irq; 162 163 bcma_chipco_gpio_intmask(cc, ~0, 0); 164 bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO); 165 166 return 0; 167 168 err_req_irq: 169 for (gpio = 0; gpio < chip->ngpio; gpio++) { 170 int irq = irq_find_mapping(cc->irq_domain, gpio); 171 172 irq_dispose_mapping(irq); 173 } 174 irq_domain_remove(cc->irq_domain); 175 err_irq_domain: 176 return err; 177 } 178 179 static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc) 180 { 181 struct gpio_chip *chip = &cc->gpio; 182 int gpio; 183 184 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) 185 return; 186 187 bcma_cc_mask32(cc, BCMA_CC_IRQMASK, ~BCMA_CC_IRQ_GPIO); 188 free_irq(bcma_core_irq(cc->core, 0), cc); 189 for (gpio = 0; gpio < chip->ngpio; gpio++) { 190 int irq = irq_find_mapping(cc->irq_domain, gpio); 191 192 irq_dispose_mapping(irq); 193 } 194 irq_domain_remove(cc->irq_domain); 195 } 196 #else 197 static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc) 198 { 199 return 0; 200 } 201 202 static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc) 203 { 204 } 205 #endif 206 207 int bcma_gpio_init(struct bcma_drv_cc *cc) 208 { 209 struct bcma_bus *bus = cc->core->bus; 210 struct gpio_chip *chip = &cc->gpio; 211 int err; 212 213 chip->label = "bcma_gpio"; 214 chip->owner = THIS_MODULE; 215 chip->request = bcma_gpio_request; 216 chip->free = bcma_gpio_free; 217 chip->get = bcma_gpio_get_value; 218 chip->set = bcma_gpio_set_value; 219 chip->direction_input = bcma_gpio_direction_input; 220 chip->direction_output = bcma_gpio_direction_output; 221 #if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X) 222 chip->to_irq = bcma_gpio_to_irq; 223 #endif 224 #if IS_BUILTIN(CONFIG_OF) 225 if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 226 chip->of_node = cc->core->dev.of_node; 227 #endif 228 switch (bus->chipinfo.id) { 229 case BCMA_CHIP_ID_BCM4707: 230 case BCMA_CHIP_ID_BCM5357: 231 case BCMA_CHIP_ID_BCM53572: 232 chip->ngpio = 32; 233 break; 234 default: 235 chip->ngpio = 16; 236 } 237 238 /* 239 * Register SoC GPIO devices with absolute GPIO pin base. 240 * On MIPS, we don't have Device Tree and we can't use relative (per chip) 241 * GPIO numbers. 242 * On some ARM devices, user space may want to access some system GPIO 243 * pins directly, which is easier to do with a predictable GPIO base. 244 */ 245 if (IS_BUILTIN(CONFIG_BCM47XX) || 246 cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 247 chip->base = bus->num * BCMA_GPIO_MAX_PINS; 248 else 249 chip->base = -1; 250 251 err = bcma_gpio_irq_domain_init(cc); 252 if (err) 253 return err; 254 255 err = gpiochip_add(chip); 256 if (err) { 257 bcma_gpio_irq_domain_exit(cc); 258 return err; 259 } 260 261 return 0; 262 } 263 264 int bcma_gpio_unregister(struct bcma_drv_cc *cc) 265 { 266 bcma_gpio_irq_domain_exit(cc); 267 gpiochip_remove(&cc->gpio); 268 return 0; 269 } 270