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/driver.h> 12 #include <linux/interrupt.h> 13 #include <linux/export.h> 14 #include <linux/property.h> 15 16 #include <linux/bcma/bcma.h> 17 18 #include "bcma_private.h" 19 20 #define BCMA_GPIO_MAX_PINS 32 21 22 static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio) 23 { 24 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 25 26 return !!bcma_chipco_gpio_in(cc, 1 << gpio); 27 } 28 29 static int bcma_gpio_set_value(struct gpio_chip *chip, unsigned int gpio, 30 int value) 31 { 32 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 33 34 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 35 36 return 0; 37 } 38 39 static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) 40 { 41 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 42 43 bcma_chipco_gpio_outen(cc, 1 << gpio, 0); 44 return 0; 45 } 46 47 static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, 48 int value) 49 { 50 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 51 52 bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio); 53 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 54 return 0; 55 } 56 57 static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio) 58 { 59 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 60 61 bcma_chipco_gpio_control(cc, 1 << gpio, 0); 62 /* clear pulldown */ 63 bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0); 64 /* Set pullup */ 65 bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio); 66 67 return 0; 68 } 69 70 static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio) 71 { 72 struct bcma_drv_cc *cc = gpiochip_get_data(chip); 73 74 /* clear pullup */ 75 bcma_chipco_gpio_pullup(cc, 1 << gpio, 0); 76 } 77 78 #if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X) 79 80 static void bcma_gpio_irq_unmask(struct irq_data *d) 81 { 82 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 83 struct bcma_drv_cc *cc = gpiochip_get_data(gc); 84 int gpio = irqd_to_hwirq(d); 85 u32 val = bcma_chipco_gpio_in(cc, BIT(gpio)); 86 87 gpiochip_enable_irq(gc, gpio); 88 bcma_chipco_gpio_polarity(cc, BIT(gpio), val); 89 bcma_chipco_gpio_intmask(cc, BIT(gpio), BIT(gpio)); 90 } 91 92 static void bcma_gpio_irq_mask(struct irq_data *d) 93 { 94 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 95 struct bcma_drv_cc *cc = gpiochip_get_data(gc); 96 int gpio = irqd_to_hwirq(d); 97 98 bcma_chipco_gpio_intmask(cc, BIT(gpio), 0); 99 gpiochip_disable_irq(gc, gpio); 100 } 101 102 static const struct irq_chip bcma_gpio_irq_chip = { 103 .name = "BCMA-GPIO", 104 .irq_mask = bcma_gpio_irq_mask, 105 .irq_unmask = bcma_gpio_irq_unmask, 106 .flags = IRQCHIP_IMMUTABLE, 107 GPIOCHIP_IRQ_RESOURCE_HELPERS, 108 }; 109 110 static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id) 111 { 112 struct bcma_drv_cc *cc = dev_id; 113 struct gpio_chip *gc = &cc->gpio; 114 u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN); 115 u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ); 116 u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL); 117 unsigned long irqs = (val ^ pol) & mask; 118 int gpio; 119 120 if (!irqs) 121 return IRQ_NONE; 122 123 for_each_set_bit(gpio, &irqs, gc->ngpio) 124 generic_handle_domain_irq_safe(gc->irq.domain, gpio); 125 bcma_chipco_gpio_polarity(cc, irqs, val & irqs); 126 127 return IRQ_HANDLED; 128 } 129 130 static int bcma_gpio_irq_init(struct bcma_drv_cc *cc) 131 { 132 struct gpio_chip *chip = &cc->gpio; 133 struct gpio_irq_chip *girq = &chip->irq; 134 int hwirq, err; 135 136 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) 137 return 0; 138 139 hwirq = bcma_core_irq(cc->core, 0); 140 err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio", 141 cc); 142 if (err) 143 return err; 144 145 bcma_chipco_gpio_intmask(cc, ~0, 0); 146 bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO); 147 148 gpio_irq_chip_set_chip(girq, &bcma_gpio_irq_chip); 149 /* This will let us handle the parent IRQ in the driver */ 150 girq->parent_handler = NULL; 151 girq->num_parents = 0; 152 girq->parents = NULL; 153 girq->default_type = IRQ_TYPE_NONE; 154 girq->handler = handle_simple_irq; 155 156 return 0; 157 } 158 159 static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc) 160 { 161 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) 162 return; 163 164 bcma_cc_mask32(cc, BCMA_CC_IRQMASK, ~BCMA_CC_IRQ_GPIO); 165 free_irq(bcma_core_irq(cc->core, 0), cc); 166 } 167 #else 168 static int bcma_gpio_irq_init(struct bcma_drv_cc *cc) 169 { 170 return 0; 171 } 172 173 static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc) 174 { 175 } 176 #endif 177 178 int bcma_gpio_init(struct bcma_drv_cc *cc) 179 { 180 struct bcma_bus *bus = cc->core->bus; 181 struct gpio_chip *chip = &cc->gpio; 182 int err; 183 184 chip->label = "bcma_gpio"; 185 chip->owner = THIS_MODULE; 186 chip->request = bcma_gpio_request; 187 chip->free = bcma_gpio_free; 188 chip->get = bcma_gpio_get_value; 189 chip->set_rv = bcma_gpio_set_value; 190 chip->direction_input = bcma_gpio_direction_input; 191 chip->direction_output = bcma_gpio_direction_output; 192 chip->parent = bus->dev; 193 chip->fwnode = dev_fwnode(&cc->core->dev); 194 195 switch (bus->chipinfo.id) { 196 case BCMA_CHIP_ID_BCM4707: 197 case BCMA_CHIP_ID_BCM5357: 198 case BCMA_CHIP_ID_BCM53572: 199 case BCMA_CHIP_ID_BCM53573: 200 case BCMA_CHIP_ID_BCM47094: 201 chip->ngpio = 32; 202 break; 203 default: 204 chip->ngpio = 16; 205 } 206 207 /* 208 * Register SoC GPIO devices with absolute GPIO pin base. 209 * On MIPS, we don't have Device Tree and we can't use relative (per chip) 210 * GPIO numbers. 211 * On some ARM devices, user space may want to access some system GPIO 212 * pins directly, which is easier to do with a predictable GPIO base. 213 */ 214 if (IS_BUILTIN(CONFIG_BCM47XX) || 215 cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 216 chip->base = bus->num * BCMA_GPIO_MAX_PINS; 217 else 218 chip->base = -1; 219 220 err = bcma_gpio_irq_init(cc); 221 if (err) 222 return err; 223 224 err = gpiochip_add_data(chip, cc); 225 if (err) { 226 bcma_gpio_irq_exit(cc); 227 return err; 228 } 229 230 return 0; 231 } 232 233 int bcma_gpio_unregister(struct bcma_drv_cc *cc) 234 { 235 bcma_gpio_irq_exit(cc); 236 gpiochip_remove(&cc->gpio); 237 return 0; 238 } 239