release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/media/video/cx18/cx18-irq.c

   1 /*
   2  *  cx18 interrupt handling
   3  *
   4  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
   5  *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20  *  02111-1307  USA
  21  */
  22
  23 #include "cx18-driver.h"
  24 #include "cx18-io.h"
  25 #include "cx18-irq.h"
  26 #include "cx18-mailbox.h"
  27 #include "cx18-scb.h"
  28
  29 static void xpu_ack(struct cx18 *cx, u32 sw2)
  30 {
  31         if (sw2 & IRQ_CPU_TO_EPU_ACK)
  32                 wake_up(&cx->mb_cpu_waitq);
  33         if (sw2 & IRQ_APU_TO_EPU_ACK)
  34                 wake_up(&cx->mb_apu_waitq);
  35 }
  36
  37 static void epu_cmd(struct cx18 *cx, u32 sw1)
  38 {
  39         if (sw1 & IRQ_CPU_TO_EPU)
  40                 cx18_api_epu_cmd_irq(cx, CPU);
  41         if (sw1 & IRQ_APU_TO_EPU)
  42                 cx18_api_epu_cmd_irq(cx, APU);
  43 }
  44
  45 irqreturn_t cx18_irq_handler(int irq, void *dev_id)
  46 {
  47         struct cx18 *cx = (struct cx18 *)dev_id;
  48         u32 sw1, sw2, hw2;
  49
  50         sw1 = cx18_read_reg(cx, SW1_INT_STATUS) & cx->sw1_irq_mask;
  51         sw2 = cx18_read_reg(cx, SW2_INT_STATUS) & cx->sw2_irq_mask;
  52         hw2 = cx18_read_reg(cx, HW2_INT_CLR_STATUS) & cx->hw2_irq_mask;
  53
  54         if (sw1)
  55                 cx18_write_reg_expect(cx, sw1, SW1_INT_STATUS, ~sw1, sw1);
  56         if (sw2)
  57                 cx18_write_reg_expect(cx, sw2, SW2_INT_STATUS, ~sw2, sw2);
  58         if (hw2)
  59                 cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
  60
  61         if (sw1 || sw2 || hw2)
  62                 CX18_DEBUG_HI_IRQ("received interrupts "
  63                                   "SW1: %x  SW2: %x  HW2: %x\n", sw1, sw2, hw2);
  64
  65         /*
  66          * SW1 responses have to happen first.  The sending XPU times out the
  67          * incoming mailboxes on us rather rapidly.
  68          */
  69         if (sw1)
  70                 epu_cmd(cx, sw1);
  71
  72         /* To do: interrupt-based I2C handling
  73         if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {
  74         }
  75         */
  76
  77         if (sw2)
  78                 xpu_ack(cx, sw2);
  79
  80         return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
  81 }