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 inline struct bcma_drv_cc *bcma_gpio_get_cc(struct gpio_chip *chip) 21 { 22 return container_of(chip, struct bcma_drv_cc, gpio); 23 } 24 25 static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio) 26 { 27 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 28 29 return !!bcma_chipco_gpio_in(cc, 1 << gpio); 30 } 31 32 static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio, 33 int value) 34 { 35 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 36 37 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 38 } 39 40 static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) 41 { 42 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 43 44 bcma_chipco_gpio_outen(cc, 1 << gpio, 0); 45 return 0; 46 } 47 48 static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, 49 int value) 50 { 51 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 52 53 bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio); 54 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); 55 return 0; 56 } 57 58 static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio) 59 { 60 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 61 62 bcma_chipco_gpio_control(cc, 1 << gpio, 0); 63 /* clear pulldown */ 64 bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0); 65 /* Set pullup */ 66 bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio); 67 68 return 0; 69 } 70 71 static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio) 72 { 73 struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); 74 75 /* clear pullup */ 76 bcma_chipco_gpio_pullup(cc, 1 << gpio, 0); 77 } 78 79 #if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X) 80 81 static void bcma_gpio_irq_unmask(struct irq_data *d) 82 { 83 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 84 struct bcma_drv_cc *cc = bcma_gpio_get_cc(gc); 85 int gpio = irqd_to_hwirq(d); 86 u32 val = bcma_chipco_gpio_in(cc, BIT(gpio)); 87 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 = bcma_gpio_get_cc(gc); 96 int gpio = irqd_to_hwirq(d); 97 98 bcma_chipco_gpio_intmask(cc, BIT(gpio), 0); 99 } 100 101 static struct irq_chip bcma_gpio_irq_chip = { 102 .name = "BCMA-GPIO", 103 .irq_mask = bcma_gpio_irq_mask, 104 .irq_unmask = bcma_gpio_irq_unmask, 105 }; 106 107 static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id) 108 { 109 struct bcma_drv_cc *cc = dev_id; 110 struct gpio_chip *gc = &cc->gpio; 111 u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN); 112 u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ); 113 u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL); 114 unsigned long irqs = (val ^ pol) & mask; 115 int gpio; 116 117 if (!irqs) 118 return IRQ_NONE; 119 120 for_each_set_bit(gpio, &irqs, gc->ngpio) 121 generic_handle_irq(irq_find_mapping(gc->irqdomain, gpio)); 122 bcma_chipco_gpio_polarity(cc, irqs, val & irqs); 123 124 return IRQ_HANDLED; 125 } 126 127 static int bcma_gpio_irq_init(struct bcma_drv_cc *cc) 128 { 129 struct gpio_chip *chip = &cc->gpio; 130 int hwirq, err; 131 132 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) 133 return 0; 134 135 hwirq = bcma_core_irq(cc->core, 0); 136 err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio", 137 cc); 138 if (err) 139 return err; 140 141 bcma_chipco_gpio_intmask(cc, ~0, 0); 142 bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO); 143 144 err = gpiochip_irqchip_add(chip, 145 &bcma_gpio_irq_chip, 146 0, 147 handle_simple_irq, 148 IRQ_TYPE_NONE); 149 if (err) { 150 free_irq(hwirq, cc); 151 return err; 152 } 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->owner = THIS_MODULE; 191 chip->dev = bcma_bus_get_host_dev(bus); 192 #if IS_BUILTIN(CONFIG_OF) 193 if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 194 chip->of_node = cc->core->dev.of_node; 195 #endif 196 switch (bus->chipinfo.id) { 197 case BCMA_CHIP_ID_BCM4707: 198 case BCMA_CHIP_ID_BCM5357: 199 case BCMA_CHIP_ID_BCM53572: 200 chip->ngpio = 32; 201 break; 202 default: 203 chip->ngpio = 16; 204 } 205 206 /* 207 * Register SoC GPIO devices with absolute GPIO pin base. 208 * On MIPS, we don't have Device Tree and we can't use relative (per chip) 209 * GPIO numbers. 210 * On some ARM devices, user space may want to access some system GPIO 211 * pins directly, which is easier to do with a predictable GPIO base. 212 */ 213 if (IS_BUILTIN(CONFIG_BCM47XX) || 214 cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) 215 chip->base = bus->num * BCMA_GPIO_MAX_PINS; 216 else 217 chip->base = -1; 218 219 err = gpiochip_add(chip); 220 if (err) 221 return err; 222 223 err = bcma_gpio_irq_init(cc); 224 if (err) { 225 gpiochip_remove(chip); 226 return err; 227 } 228 229 return 0; 230 } 231 232 int bcma_gpio_unregister(struct bcma_drv_cc *cc) 233 { 234 bcma_gpio_irq_exit(cc); 235 gpiochip_remove(&cc->gpio); 236 return 0; 237 } 238