diff options
Diffstat (limited to 'arch/mips/pmcs-msp71xx/msp_hwbutton.c')
| -rw-r--r-- | arch/mips/pmcs-msp71xx/msp_hwbutton.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/mips/pmcs-msp71xx/msp_hwbutton.c b/arch/mips/pmcs-msp71xx/msp_hwbutton.c new file mode 100644 index 000000000..bb57ed9ea --- /dev/null +++ b/arch/mips/pmcs-msp71xx/msp_hwbutton.c @@ -0,0 +1,165 @@ +/* + * 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, 0, + 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); |