kernel/2.6.29.6-aldebaran-rt/arch/arm/plat-s3c64xx/irq-eint.c

   1 /* arch/arm/plat-s3c64xx/irq-eint.c
   2  *
   3  * Copyright 2008 Openmoko, Inc.
   4  * Copyright 2008 Simtec Electronics
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *      http://armlinux.simtec.co.uk/
   7  *
   8  * S3C64XX - Interrupt handling for IRQ_EINT(x)
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/gpio.h>
  18 #include <linux/irq.h>
  19 #include <linux/io.h>
  20
  21 #include <asm/hardware/vic.h>
  22
  23 #include <plat/regs-irqtype.h>
  24 #include <plat/regs-gpio.h>
  25 #include <plat/gpio-cfg.h>
  26
  27 #include <mach/map.h>
  28 #include <plat/cpu.h>
  29
  30 /* GPIO is 0x7F008xxx, */
  31 #define S3C64XX_GPIOREG(x)      (S3C64XX_VA_GPIO + (x))
  32
  33 #define S3C64XX_EINT0CON0       S3C64XX_GPIOREG(0x900)
  34 #define S3C64XX_EINT0CON1       S3C64XX_GPIOREG(0x904)
  35 #define S3C64XX_EINT0FLTCON0    S3C64XX_GPIOREG(0x910)
  36 #define S3C64XX_EINT0FLTCON1    S3C64XX_GPIOREG(0x914)
  37 #define S3C64XX_EINT0FLTCON2    S3C64XX_GPIOREG(0x918)
  38 #define S3C64XX_EINT0FLTCON3    S3C64XX_GPIOREG(0x91C)
  39
  40 #define S3C64XX_EINT0MASK       S3C64XX_GPIOREG(0x920)
  41 #define S3C64XX_EINT0PEND       S3C64XX_GPIOREG(0x924)
  42
  43
  44 #define eint_offset(irq)        ((irq) - IRQ_EINT(0))
  45 #define eint_irq_to_bit(irq)    (1 << eint_offset(irq))
  46
  47 static inline void s3c_irq_eint_mask(unsigned int irq)
  48 {
  49         u32 mask;
  50
  51         mask = __raw_readl(S3C64XX_EINT0MASK);
  52         mask |= eint_irq_to_bit(irq);
  53         __raw_writel(mask, S3C64XX_EINT0MASK);
  54 }
  55
  56 static void s3c_irq_eint_unmask(unsigned int irq)
  57 {
  58         u32 mask;
  59
  60         mask = __raw_readl(S3C64XX_EINT0MASK);
  61         mask &= ~eint_irq_to_bit(irq);
  62         __raw_writel(mask, S3C64XX_EINT0MASK);
  63 }
  64
  65 static inline void s3c_irq_eint_ack(unsigned int irq)
  66 {
  67         __raw_writel(eint_irq_to_bit(irq), S3C64XX_EINT0PEND);
  68 }
  69
  70 static void s3c_irq_eint_maskack(unsigned int irq)
  71 {
  72         /* compiler should in-line these */
  73         s3c_irq_eint_mask(irq);
  74         s3c_irq_eint_ack(irq);
  75 }
  76
  77 static int s3c_irq_eint_set_type(unsigned int irq, unsigned int type)
  78 {
  79         int offs = eint_offset(irq);
  80         int pin;
  81         int shift;
  82         u32 ctrl, mask;
  83         u32 newvalue = 0;
  84         void __iomem *reg;
  85
  86         if (offs > 27)
  87                 return -EINVAL;
  88
  89         if (offs <= 15)
  90                 reg = S3C64XX_EINT0CON0;
  91         else
  92                 reg = S3C64XX_EINT0CON1;
  93
  94         switch (type) {
  95         case IRQ_TYPE_NONE:
  96                 printk(KERN_WARNING "No edge setting!\n");
  97                 break;
  98
  99         case IRQ_TYPE_EDGE_RISING:
 100                 newvalue = S3C2410_EXTINT_RISEEDGE;
 101                 break;
 102
 103         case IRQ_TYPE_EDGE_FALLING:
 104                 newvalue = S3C2410_EXTINT_FALLEDGE;
 105                 break;
 106
 107         case IRQ_TYPE_EDGE_BOTH:
 108                 newvalue = S3C2410_EXTINT_BOTHEDGE;
 109                 break;
 110
 111         case IRQ_TYPE_LEVEL_LOW:
 112                 newvalue = S3C2410_EXTINT_LOWLEV;
 113                 break;
 114
 115         case IRQ_TYPE_LEVEL_HIGH:
 116                 newvalue = S3C2410_EXTINT_HILEV;
 117                 break;
 118
 119         default:
 120                 printk(KERN_ERR "No such irq type %d", type);
 121                 return -1;
 122         }
 123
 124         shift = (offs / 2) * 4;
 125         mask = 0x7 << shift;
 126
 127         ctrl = __raw_readl(reg);
 128         ctrl &= ~mask;
 129         ctrl |= newvalue << shift;
 130         __raw_writel(ctrl, reg);
 131
 132         /* set the GPIO pin appropriately */
 133
 134         if (offs < 23)
 135                 pin = S3C64XX_GPN(offs);
 136         else
 137                 pin = S3C64XX_GPM(offs - 23);
 138
 139         s3c_gpio_cfgpin(pin, S3C_GPIO_SFN(2));
 140
 141         return 0;
 142 }
 143
 144 static struct irq_chip s3c_irq_eint = {
 145         .name           = "s3c-eint",
 146         .mask           = s3c_irq_eint_mask,
 147         .unmask         = s3c_irq_eint_unmask,
 148         .mask_ack       = s3c_irq_eint_maskack,
 149         .ack            = s3c_irq_eint_ack,
 150         .set_type       = s3c_irq_eint_set_type,
 151 };
 152
 153 /* s3c_irq_demux_eint
 154  *
 155  * This function demuxes the IRQ from the group0 external interrupts,
 156  * from IRQ_EINT(0) to IRQ_EINT(27). It is designed to be inlined into
 157  * the specific handlers s3c_irq_demux_eintX_Y.
 158  */
 159 static inline void s3c_irq_demux_eint(unsigned int start, unsigned int end)
 160 {
 161         u32 status = __raw_readl(S3C64XX_EINT0PEND);
 162         u32 mask = __raw_readl(S3C64XX_EINT0MASK);
 163         unsigned int irq;
 164
 165         status &= ~mask;
 166         status >>= start;
 167         status &= (1 << (end - start + 1)) - 1;
 168
 169         for (irq = IRQ_EINT(start); irq <= IRQ_EINT(end); irq++) {
 170                 if (status & 1)
 171                         generic_handle_irq(irq);
 172
 173                 status >>= 1;
 174         }
 175 }
 176
 177 static void s3c_irq_demux_eint0_3(unsigned int irq, struct irq_desc *desc)
 178 {
 179         s3c_irq_demux_eint(0, 3);
 180 }
 181
 182 static void s3c_irq_demux_eint4_11(unsigned int irq, struct irq_desc *desc)
 183 {
 184         s3c_irq_demux_eint(4, 11);
 185 }
 186
 187 static void s3c_irq_demux_eint12_19(unsigned int irq, struct irq_desc *desc)
 188 {
 189         s3c_irq_demux_eint(12, 19);
 190 }
 191
 192 static void s3c_irq_demux_eint20_27(unsigned int irq, struct irq_desc *desc)
 193 {
 194         s3c_irq_demux_eint(20, 27);
 195 }
 196
 197 static int __init s3c64xx_init_irq_eint(void)
 198 {
 199         int irq;
 200
 201         for (irq = IRQ_EINT(0); irq <= IRQ_EINT(27); irq++) {
 202                 set_irq_chip(irq, &s3c_irq_eint);
 203                 set_irq_handler(irq, handle_level_irq);
 204                 set_irq_flags(irq, IRQF_VALID);
 205         }
 206
 207         set_irq_chained_handler(IRQ_EINT0_3, s3c_irq_demux_eint0_3);
 208         set_irq_chained_handler(IRQ_EINT4_11, s3c_irq_demux_eint4_11);
 209         set_irq_chained_handler(IRQ_EINT12_19, s3c_irq_demux_eint12_19);
 210         set_irq_chained_handler(IRQ_EINT20_27, s3c_irq_demux_eint20_27);
 211
 212         return 0;
 213 }
 214
 215 arch_initcall(s3c64xx_init_irq_eint);