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