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