diff options
| author | mbalmer <mbalmer@NetBSD.org> | 2011-08-28 07:48:50 +0000 |
|---|---|---|
| committer | mbalmer <mbalmer@NetBSD.org> | 2011-08-28 07:48:50 +0000 |
| commit | da668cdf91cdc35a69a5162bd24e7a5eca2bda4e (patch) | |
| tree | 06c3388b9e3be3a02e3b03181b9f6ea020ecd9c0 /sys/dev/gpio/gpio.c | |
| parent | 1b3a256adc36e54133a189084ba985a7dca7fd3d (diff) | |
Add a new ioctl, GPIOPULSE to gpio(4) to allow for pulsing a pin.
If a pin can pulse in hardware, that will be used, else it will
be pulsed in software. There is no way yet to set the pulse frequency
for pins that pulse in hardware. While here, make the code mpsafe and
allow more than one thread in the driver (access to ioctl is serialized).
Diffstat (limited to 'sys/dev/gpio/gpio.c')
| -rw-r--r-- | sys/dev/gpio/gpio.c | 231 |
1 files changed, 175 insertions, 56 deletions
diff --git a/sys/dev/gpio/gpio.c b/sys/dev/gpio/gpio.c index bb215b505c9..2b7466ea634 100644 --- a/sys/dev/gpio/gpio.c +++ b/sys/dev/gpio/gpio.c @@ -1,4 +1,4 @@ -/* $NetBSD: gpio.c,v 1.35 2011/08/12 08:00:52 mbalmer Exp $ */ +/* $NetBSD: gpio.c,v 1.36 2011/08/28 07:48:50 mbalmer Exp $ */ /* $OpenBSD: gpio.c,v 1.6 2006/01/14 12:33:49 grange Exp $ */ /* @@ -19,21 +19,25 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: gpio.c,v 1.35 2011/08/12 08:00:52 mbalmer Exp $"); +__KERNEL_RCSID(0, "$NetBSD: gpio.c,v 1.36 2011/08/28 07:48:50 mbalmer Exp $"); /* * General Purpose Input/Output framework. */ #include <sys/param.h> +#include <sys/callout.h> #include <sys/systm.h> #include <sys/conf.h> #include <sys/device.h> #include <sys/fcntl.h> #include <sys/ioctl.h> #include <sys/gpio.h> +#include <sys/kernel.h> #include <sys/vnode.h> #include <sys/kmem.h> +#include <sys/mutex.h> +#include <sys/condvar.h> #include <sys/queue.h> #include <sys/kauth.h> #ifdef _MODULE @@ -58,7 +62,9 @@ struct gpio_softc { gpio_pin_t *sc_pins; /* pins array */ int sc_npins; /* number of pins */ - int sc_opened; + kmutex_t sc_mtx; + kcondvar_t sc_ioctl; /* ioctl in progress */ + int sc_ioctl_busy; /* ioctl is busy */ LIST_HEAD(, gpio_dev) sc_devs; /* devices */ LIST_HEAD(, gpio_name) sc_names; /* named pins */ }; @@ -73,6 +79,9 @@ static int gpio_detach(device_t, int); static int gpio_search(device_t, cfdata_t, const int *, void *); static int gpio_print(void *, const char *); static int gpio_pinbyname(struct gpio_softc *, char *); +static void gpio_pulse(void *); +static int gpio_ioctl(struct gpio_softc *, u_long, void *, int, + struct lwp *); /* Old API */ static int gpio_ioctl_oapi(struct gpio_softc *, u_long, void *, int, @@ -85,10 +94,11 @@ CFATTACH_DECL3_NEW(gpio, sizeof(struct gpio_softc), dev_type_open(gpioopen); dev_type_close(gpioclose); dev_type_ioctl(gpioioctl); +dev_type_ioctl(gpioioctl_locked); const struct cdevsw gpio_cdevsw = { gpioopen, gpioclose, noread, nowrite, gpioioctl, - nostop, notty, nopoll, nommap, nokqfilter, D_OTHER, + nostop, notty, nopoll, nommap, nokqfilter, D_OTHER | D_MPSAFE }; extern struct cfdriver gpio_cd; @@ -144,7 +154,7 @@ gpio_attach(device_t parent, device_t self, void *aux) { struct gpio_softc *sc = device_private(self); struct gpiobus_attach_args *gba = aux; - + int pin; sc->sc_dev = self; sc->sc_gc = gba->gba_gc; sc->sc_pins = gba->gba_pins; @@ -152,8 +162,15 @@ gpio_attach(device_t parent, device_t self, void *aux) printf(": %d pins\n", sc->sc_npins); + for (pin = 0; pin < sc->sc_npins; pin++) { + callout_init(&sc->sc_pins[pin].pin_pulse, CALLOUT_MPSAFE); + callout_setfunc(&sc->sc_pins[pin].pin_pulse, gpio_pulse, + &sc->sc_pins[pin]); + } if (!pmf_device_register(self, NULL, gpio_resume)) aprint_error_dev(self, "couldn't establish power handler\n"); + mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_VM); + cv_init(&sc->sc_ioctl, "gpioctl"); /* * Attach all devices that can be connected to the GPIO pins @@ -165,11 +182,23 @@ gpio_attach(device_t parent, device_t self, void *aux) static int gpio_detach(device_t self, int flags) { - int rc; + struct gpio_softc *sc; + int pin, rc; + + sc = device_private(self); + + for (pin = 0; pin < sc->sc_npins; pin++) { + if (sc->sc_pins[pin].pin_state & GPIO_PIN_PULSE) { + callout_halt(&sc->sc_pins[pin].pin_pulse, NULL); + callout_destroy(&sc->sc_pins[pin].pin_pulse); + sc->sc_pins[pin].pin_state &= ~GPIO_PIN_PULSE; + } + } if ((rc = config_detach_children(self, flags)) != 0) return rc; - + mutex_destroy(&sc->sc_mtx); + cv_destroy(&sc->sc_ioctl); #if 0 int maj, mn; @@ -228,7 +257,7 @@ gpiobus_print(void *aux, const char *pnp) /* return 1 if all pins can be mapped, 0 if not */ int -gpio_pin_can_map(void *gpio, int offset, u_int32_t mask) +gpio_pin_can_map(void *gpio, int offset, uint32_t mask) { struct gpio_softc *sc = gpio; int npins, pin, i; @@ -250,7 +279,7 @@ gpio_pin_can_map(void *gpio, int offset, u_int32_t mask) } int -gpio_pin_map(void *gpio, int offset, u_int32_t mask, struct gpio_pinmap *map) +gpio_pin_map(void *gpio, int offset, uint32_t mask, struct gpio_pinmap *map) { struct gpio_softc *sc = gpio; int npins, pin, i; @@ -320,7 +349,7 @@ gpio_pin_caps(void *gpio, struct gpio_pinmap *map, int pin) } int -gpio_npins(u_int32_t mask) +gpio_npins(uint32_t mask) { int npins, i; @@ -332,30 +361,47 @@ gpio_npins(u_int32_t mask) } int +gpio_lock(void *data) +{ + struct gpio_softc *sc; + int error; + + error = 0; + sc = (struct gpio_softc *)data; + mutex_enter(&sc->sc_mtx); + while (sc->sc_ioctl_busy) { + error = cv_wait_sig(&sc->sc_ioctl, &sc->sc_mtx); + if (error) + break; + } + if (!error) + sc->sc_ioctl_busy = 1; + mutex_exit(&sc->sc_mtx); + return error; +} + +void +gpio_unlock(void *data) +{ + struct gpio_softc *sc; + + sc = (struct gpio_softc *)data; + mutex_enter(&sc->sc_mtx); + sc->sc_ioctl_busy = 0; + cv_signal(&sc->sc_ioctl); + mutex_exit(&sc->sc_mtx); +} + +int gpioopen(dev_t dev, int flag, int mode, struct lwp *l) { struct gpio_softc *sc; - int ret; sc = device_lookup_private(&gpio_cd, minor(dev)); if (sc == NULL) return ENXIO; - DPRINTF(("%s: opening\n", device_xname(sc->sc_dev))); - if (sc->sc_opened) { - DPRINTF(("%s: already opened\n", device_xname(sc->sc_dev))); - return EBUSY; - } - - if ((ret = gpiobus_open(sc->sc_gc, sc->sc_dev))) { - DPRINTF(("%s: gpiobus_open returned %d\n", - device_xname(sc->sc_dev), - ret)); - return ret; - } - - sc->sc_opened = 1; - return 0; + return gpiobus_open(sc->sc_gc, sc->sc_dev); } int @@ -364,10 +410,7 @@ gpioclose(dev_t dev, int flag, int mode, struct lwp *l) struct gpio_softc *sc; sc = device_lookup_private(&gpio_cd, minor(dev)); - DPRINTF(("%s: closing\n", device_xname(sc->sc_dev))); - (void)gpiobus_close(sc->sc_gc, sc->sc_dev); - sc->sc_opened = 0; - + gpiobus_close(sc->sc_gc, sc->sc_dev); return 0; } @@ -382,25 +425,63 @@ gpio_pinbyname(struct gpio_softc *sc, char *gp_name) return -1; } +static void +gpio_pulse(void *arg) +{ + struct gpio_pin *pin; + + pin = (struct gpio_pin *)arg; + if ((pin->pin_state & GPIO_PIN_PULSE) == 0) + return; + + if (pin->pin_state & GPIO_PIN_HIGH) { + gpiobus_pin_write(pin->pin_gc, pin->pin_num, GPIO_PIN_LOW); + pin->pin_state &= ~GPIO_PIN_HIGH; + callout_schedule(&pin->pin_pulse, pin->pin_ticks_off); + } else { + gpiobus_pin_write(pin->pin_gc, pin->pin_num, GPIO_PIN_HIGH); + pin->pin_state |= GPIO_PIN_HIGH; + callout_schedule(&pin->pin_pulse, pin->pin_ticks_on); + } +} + int gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) { + int error; struct gpio_softc *sc; + + sc = device_lookup_private(&gpio_cd, minor(dev)); + + error = gpio_lock(sc); + if (error) + return error; + + error = gpio_ioctl(sc, cmd, data, flag, l); + gpio_unlock(sc); + return error; +} + +static int +gpio_ioctl(struct gpio_softc *sc, u_long cmd, void *data, int flag, + struct lwp *l) +{ gpio_chipset_tag_t gc; struct gpio_info *info; struct gpio_attach *attach; struct gpio_attach_args ga; struct gpio_dev *gdev; struct gpio_req *req; + struct gpio_pulse *pulse; struct gpio_name *nm; struct gpio_set *set; + struct gpio_pin *gpin; device_t dv; cfdata_t cf; kauth_cred_t cred; int locs[GPIOCF_NLOCS]; int pin, value, flags, npins; - sc = device_lookup_private(&gpio_cd, minor(dev)); gc = sc->sc_gc; if (cmd != GPIOINFO && !device_is_active(sc->sc_dev)) { @@ -427,11 +508,9 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) case GPIOREAD: req = (struct gpio_req *)data; - if (req->gp_name[0] != '\0') { + if (req->gp_name[0] != '\0') pin = gpio_pinbyname(sc, req->gp_name); - if (pin == -1) - return EINVAL; - } else + else pin = req->gp_pin; if (pin < 0 || pin >= sc->sc_npins) @@ -451,11 +530,9 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) req = (struct gpio_req *)data; - if (req->gp_name[0] != '\0') { + if (req->gp_name[0] != '\0') pin = gpio_pinbyname(sc, req->gp_name); - if (pin == -1) - return EINVAL; - } else + else pin = req->gp_pin; if (pin < 0 || pin >= sc->sc_npins) @@ -473,23 +550,68 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) if (value != GPIO_PIN_LOW && value != GPIO_PIN_HIGH) return EINVAL; + if (sc->sc_pins[pin].pin_state & GPIO_PIN_PULSE) { + callout_halt(&sc->sc_pins[pin].pin_pulse, NULL); + sc->sc_pins[pin].pin_state &= ~GPIO_PIN_PULSE; + } gpiobus_pin_write(gc, pin, value); /* return old value */ req->gp_value = sc->sc_pins[pin].pin_state; /* update current value */ sc->sc_pins[pin].pin_state = value; break; + case GPIOPULSE: + if ((flag & FWRITE) == 0) + return EBADF; + + pulse = (struct gpio_pulse *)data; + if (pulse->gp_name[0] != '\0') + pin = gpio_pinbyname(sc, pulse->gp_name); + else + pin = pulse->gp_pin; + + if (pin < 0 || pin >= sc->sc_npins) + return EINVAL; + + gpin = &sc->sc_pins[pin]; + if (gpin->pin_mapped) + return EBUSY; + + if (!(gpin->pin_flags & GPIO_PIN_SET) && + kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET, + NULL, NULL, NULL, NULL)) + return EPERM; + + if (gpin->pin_flags & GPIO_PIN_PULSATE) { + gpiobus_pin_write(gc, pin, GPIO_PIN_HIGH); + gpin->pin_state = GPIO_PIN_PULSE; + return 0; + } + + if (gpin->pin_state & GPIO_PIN_PULSE) + callout_halt(&gpin->pin_pulse, NULL); + + gpin->pin_gc = gc; + + gpin->pin_ticks_on = tvtohz(&pulse->gp_pulse_on); + gpin->pin_ticks_off = tvtohz(&pulse->gp_pulse_off); + if (gpin->pin_ticks_on == 0 || gpin->pin_ticks_off == 0) { + gpin->pin_ticks_on = hz / 2; + gpin->pin_ticks_off = hz / 2; + } + gpiobus_pin_write(gc, pin, GPIO_PIN_HIGH); + gpin->pin_state = GPIO_PIN_HIGH | GPIO_PIN_PULSE; + callout_schedule(&gpin->pin_pulse, gpin->pin_ticks_on); + break; case GPIOTOGGLE: if ((flag & FWRITE) == 0) return EBADF; req = (struct gpio_req *)data; - if (req->gp_name[0] != '\0') { + if (req->gp_name[0] != '\0') pin = gpio_pinbyname(sc, req->gp_name); - if (pin == -1) - return EINVAL; - } else + else pin = req->gp_pin; if (pin < 0 || pin >= sc->sc_npins) @@ -526,9 +648,10 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) ga.ga_dvname = attach->ga_dvname; ga.ga_offset = attach->ga_offset; ga.ga_mask = attach->ga_mask; - DPRINTF(("%s: attach %s with offset %d and mask 0x%02x\n", - device_xname(sc->sc_dev), ga.ga_dvname, ga.ga_offset, - ga.ga_mask)); + ga.ga_nolock = 1; + DPRINTF(("%s: attach %s with offset %d and mask " + "0x%02x\n", device_xname(sc->sc_dev), ga.ga_dvname, + ga.ga_offset, ga.ga_mask)); locs[GPIOCF_OFFSET] = ga.ga_offset; locs[GPIOCF_MASK] = ga.ga_mask; @@ -546,7 +669,7 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) return EINVAL; } else return EINVAL; - break; + return 0; case GPIODETACH: if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET, NULL, NULL, NULL, NULL)) @@ -566,7 +689,6 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) } } return EINVAL; - break; case GPIOSET: if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET, NULL, NULL, NULL, NULL)) @@ -574,12 +696,11 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) set = (struct gpio_set *)data; - if (set->gp_name[0] != '\0') { + if (set->gp_name[0] != '\0') pin = gpio_pinbyname(sc, set->gp_name); - if (pin == -1) - return EINVAL; - } else + else pin = set->gp_pin; + if (pin < 0 || pin >= sc->sc_npins) return EINVAL; flags = set->gp_flags; @@ -629,11 +750,9 @@ gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) return EPERM; set = (struct gpio_set *)data; - if (set->gp_name[0] != '\0') { + if (set->gp_name[0] != '\0') pin = gpio_pinbyname(sc, set->gp_name); - if (pin == -1) - return EINVAL; - } else + else pin = set->gp_pin; if (pin < 0 || pin >= sc->sc_npins) |
