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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 | /* * $Id: gpio.c,v 1.4 2003/05/19 22:24:18 lethal Exp $ * by Greg Banks <gbanks@pocketpenguins.com> * (c) 2000 PocketPenguins Inc * * GPIO pin support for HD64465 companion chip. */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/sched.h> #include <linux/ioport.h> #include <asm/io.h> #include <asm/hd64465/gpio.h> #define _PORTOF(portpin) (((portpin)>>3)&0x7) #define _PINOF(portpin) ((portpin)&0x7) /* Register addresses parametrised on port */ #define GPIO_CR(port) (HD64465_REG_GPACR+((port)<<1)) #define GPIO_DR(port) (HD64465_REG_GPADR+((port)<<1)) #define GPIO_ICR(port) (HD64465_REG_GPAICR+((port)<<1)) #define GPIO_ISR(port) (HD64465_REG_GPAISR+((port)<<1)) #define GPIO_NPORTS 5 #define MODNAME "hd64465_gpio" EXPORT_SYMBOL(hd64465_gpio_configure); EXPORT_SYMBOL(hd64465_gpio_get_pin); EXPORT_SYMBOL(hd64465_gpio_get_port); EXPORT_SYMBOL(hd64465_gpio_register_irq); EXPORT_SYMBOL(hd64465_gpio_set_pin); EXPORT_SYMBOL(hd64465_gpio_set_port); EXPORT_SYMBOL(hd64465_gpio_unregister_irq); /* TODO: each port should be protected with a spinlock */ void hd64465_gpio_configure(int portpin, int direction) { unsigned short cr; unsigned int shift = (_PINOF(portpin)<<1); cr = inw(GPIO_CR(_PORTOF(portpin))); cr &= ~(3<<shift); cr |= direction<<shift; outw(cr, GPIO_CR(_PORTOF(portpin))); } void hd64465_gpio_set_pin(int portpin, unsigned int value) { unsigned short d; unsigned short mask = 1<<(_PINOF(portpin)); d = inw(GPIO_DR(_PORTOF(portpin))); if (value) d |= mask; else d &= ~mask; outw(d, GPIO_DR(_PORTOF(portpin))); } unsigned int hd64465_gpio_get_pin(int portpin) { return inw(GPIO_DR(_PORTOF(portpin))) & (1<<(_PINOF(portpin))); } /* TODO: for cleaner atomicity semantics, add a mask to this routine */ void hd64465_gpio_set_port(int port, unsigned int value) { outw(value, GPIO_DR(port)); } unsigned int hd64465_gpio_get_port(int port) { return inw(GPIO_DR(port)); } static struct { void (*func)(int portpin, void *dev); void *dev; } handlers[GPIO_NPORTS * 8]; static irqreturn_t hd64465_gpio_interrupt(int irq, void *dev, struct pt_regs *regs) { unsigned short port, pin, isr, mask, portpin; for (port=0 ; port<GPIO_NPORTS ; port++) { isr = inw(GPIO_ISR(port)); for (pin=0 ; pin<8 ; pin++) { mask = 1<<pin; if (isr & mask) { portpin = (port<<3)|pin; if (handlers[portpin].func != 0) handlers[portpin].func(portpin, handlers[portpin].dev); else printk(KERN_NOTICE "unexpected GPIO interrupt, pin %c%d\n", port+'A', (int)pin); } } /* Write 1s back to ISR to clear it? That's what the manual says.. */ outw(isr, GPIO_ISR(port)); } return IRQ_HANDLED; } void hd64465_gpio_register_irq(int portpin, int mode, void (*handler)(int portpin, void *dev), void *dev) { unsigned long flags; unsigned short icr, mask; if (handler == 0) return; local_irq_save(flags); handlers[portpin].func = handler; handlers[portpin].dev = dev; /* * Configure Interrupt Control Register */ icr = inw(GPIO_ICR(_PORTOF(portpin))); mask = (1<<_PINOF(portpin)); /* unmask interrupt */ icr &= ~mask; /* set TS bit */ mask <<= 8; icr &= ~mask; if (mode == HD64465_GPIO_RISING) icr |= mask; outw(icr, GPIO_ICR(_PORTOF(portpin))); local_irq_restore(flags); } void hd64465_gpio_unregister_irq(int portpin) { unsigned long flags; unsigned short icr; local_irq_save(flags); /* * Configure Interrupt Control Register */ icr = inw(GPIO_ICR(_PORTOF(portpin))); icr |= (1<<_PINOF(portpin)); /* mask interrupt */ outw(icr, GPIO_ICR(_PORTOF(portpin))); handlers[portpin].func = 0; handlers[portpin].dev = 0; local_irq_restore(flags); } static int __init hd64465_gpio_init(void) { if (!request_region(HD64465_REG_GPACR, 0x1000, MODNAME)) return -EBUSY; if (request_irq(HD64465_IRQ_GPIO, hd64465_gpio_interrupt, SA_INTERRUPT, MODNAME, 0)) goto out_irqfailed; printk("HD64465 GPIO layer on irq %d\n", HD64465_IRQ_GPIO); return 0; out_irqfailed: release_region(HD64465_REG_GPACR, 0x1000); return -EINVAL; } static void __exit hd64465_gpio_exit(void) { release_region(HD64465_REG_GPACR, 0x1000); free_irq(HD64465_IRQ_GPIO, 0); } module_init(hd64465_gpio_init); module_exit(hd64465_gpio_exit); MODULE_LICENSE("GPL"); |