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