/* * Sets up interrupt handlers for various hardware switches which are * connected to interrupt lines. * * Copyright 2005-2207 PMC-Sierra, Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/interrupt.h> #include <msp_int.h> #include <msp_regs.h> #include <msp_regops.h> /* For hwbutton_interrupt->initial_state */ #define HWBUTTON_HI 0x1 #define HWBUTTON_LO 0x2 /* * This struct describes a hardware button */ struct hwbutton_interrupt { char *name; /* Name of button */ int irq; /* Actual LINUX IRQ */ int eirq; /* Extended IRQ number (0-7) */ int initial_state; /* The "normal" state of the switch */ void (*handle_hi)(void *); /* Handler: switch input has gone HI */ void (*handle_lo)(void *); /* Handler: switch input has gone LO */ void *data; /* Optional data to pass to handler */ }; #ifdef CONFIG_PMC_MSP7120_GW extern void msp_restart(char *); static void softreset_push(void *data) { printk(KERN_WARNING "SOFTRESET switch was pushed\n"); /* * In the future you could move this to the release handler, * timing the difference between the 'push' and 'release', and only * doing this ungraceful restart if the button has been down for * a certain amount of time; otherwise doing a graceful restart. */ msp_restart(NULL); } static void softreset_release(void *data) { printk(KERN_WARNING "SOFTRESET switch was released\n"); /* Do nothing */ } static void standby_on(void *data) { printk(KERN_WARNING "STANDBY switch was set to ON (not implemented)\n"); /* TODO: Put board in standby mode */ } static void standby_off(void *data) { printk(KERN_WARNING "STANDBY switch was set to OFF (not implemented)\n"); /* TODO: Take out of standby mode */ } static struct hwbutton_interrupt softreset_sw = { .name = "Softreset button", .irq = MSP_INT_EXT0, .eirq = 0, .initial_state = HWBUTTON_HI, .handle_hi = softreset_release, .handle_lo = softreset_push, .data = NULL, }; static struct hwbutton_interrupt standby_sw = { .name = "Standby switch", .irq = MSP_INT_EXT1, .eirq = 1, .initial_state = HWBUTTON_HI, .handle_hi = standby_off, .handle_lo = standby_on, .data = NULL, }; #endif /* CONFIG_PMC_MSP7120_GW */ static irqreturn_t hwbutton_handler(int irq, void *data) { struct hwbutton_interrupt *hirq = data; unsigned long cic_ext = *CIC_EXT_CFG_REG; if (CIC_EXT_IS_ACTIVE_HI(cic_ext, hirq->eirq)) { /* Interrupt: pin is now HI */ CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq); hirq->handle_hi(hirq->data); } else { /* Interrupt: pin is now LO */ CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq); hirq->handle_lo(hirq->data); } /* * Invert the POLARITY of this level interrupt to ack the interrupt * Thus next state change will invoke the opposite message */ *CIC_EXT_CFG_REG = cic_ext; return IRQ_HANDLED; } static int msp_hwbutton_register(struct hwbutton_interrupt *hirq) { unsigned long cic_ext; if (hirq->handle_hi == NULL || hirq->handle_lo == NULL) return -EINVAL; cic_ext = *CIC_EXT_CFG_REG; CIC_EXT_SET_TRIGGER_LEVEL(cic_ext, hirq->eirq); if (hirq->initial_state == HWBUTTON_HI) CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq); else CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq); *CIC_EXT_CFG_REG = cic_ext; return request_irq(hirq->irq, hwbutton_handler, IRQF_DISABLED, hirq->name, hirq); } static int __init msp_hwbutton_setup(void) { #ifdef CONFIG_PMC_MSP7120_GW msp_hwbutton_register(&softreset_sw); msp_hwbutton_register(&standby_sw); #endif return 0; } subsys_initcall(msp_hwbutton_setup);