diff options
| -rw-r--r-- | share/man/man4/spigen.4 | 206 | ||||
| -rw-r--r-- | sys/dev/spibus/ofw_spibus.c | 6 | ||||
| -rw-r--r-- | sys/dev/spibus/spibus.c | 46 | ||||
| -rw-r--r-- | sys/dev/spibus/spibusvar.h | 8 | ||||
| -rw-r--r-- | sys/dev/spibus/spigen.c | 64 | ||||
| -rw-r--r-- | sys/modules/spigen/Makefile | 12 | ||||
| -rw-r--r-- | sys/sys/spigenio.h | 2 |
7 files changed, 299 insertions, 45 deletions
diff --git a/share/man/man4/spigen.4 b/share/man/man4/spigen.4 new file mode 100644 index 0000000..f432fb7 --- /dev/null +++ b/share/man/man4/spigen.4 @@ -0,0 +1,206 @@ +.\" +.\" Copyright (c) 2018 Ian Lepore <ian@freebsd.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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. +.\" +.\" $FreeBSD$ +.\" +.Dd April 7, 2018 +.Dt SPIGEN 4 +.Os +.Sh NAME +.Nm spigen +.Nd SPI generic I/O device driver +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following lines in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device spi" +.Cd "device spibus" +.Cd "device spigen" +.Ed +.Pp +Alternatively, to load the driver as a +module at boot time, place the following line in +.Xr loader.conf 5 : +.Bd -literal -offset indent +spigen_load="YES" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides direct access to a slave device on the SPI bus. +Each instance of a +.Nm +device is associated with a single chip-select +line on the bus, and all I/O performed through that instance is done +with that chip-select line asserted. +.Pp +SPI data transfers are inherently bi-directional; there are not separate +read and write operations. +When commands and data are sent to a device, data also comes back from +the device, although in some cases the data may not be useful (or even +documented or predictable for some devices). +Likewise on a read operation, whatever data is in the buffer at the start +of the operation is sent to (and typically ignored by) the device, with each +outgoing byte then replaced in the buffer by the corresponding incoming byte. +Thus, all buffers passed to the transfer functions are both input and +output buffers. +.Pp +The +.Nm +driver provides access to the SPI slave device with the following +.Xr ioctl 2 +calls, defined in +.In sys/spigenio.h : +.Bl -tag -width indent +.It Dv SPIGENIOC_TRANSFER Pq Vt "struct spigen_transfer" +Transfer a command and optional associated data to/from the device, +using the buffers described by the st_command and st_data fields in the +.Vt spigen_transfer . +Set +.Vt st_data.iov_len +to zero if there is no data associated with the command. +.Bd -literal +struct spigen_transfer { + struct iovec st_command; + struct iovec st_data; +}; +.Ed +.It Dv SPIGENIOC_TRANSFER_MMAPPED Pq Vt "spigen_transfer_mmapped" +Transfer a command and optional associated data to/from the device. +The buffers for the transfer are a previously-mmap'd region. +The length of the command and data within that region are described by the +.Vt stm_command_length +and +.Vt stm_data_length +fields of +.Vt spigen_transfer_mmapped . +If +.Vt stm_data_length +is non-zero, the data appears in the memory region immediately +following the command (that is, at offset +.Vt stm_command_length +from the start of the mapped region). +.Bd -literal +struct spigen_transfer_mmapped { + size_t stm_command_length; + size_t stm_data_length; +}; +.Ed +.It Dv SPIGENIOC_GET_CLOCK_SPEED Pq Vt uint32_t +Get the maximum clock speed (bus frequency in Hertz) to be used +when communicating with this slave device. +.It Dv SPIGENIOC_SET_CLOCK_SPEED Pq Vt uint32_t +Set the maximum clock speed (bus frequency in Hertz) to be used +when communicating with this slave device. +The setting remains in effect for subsequent transfers; it +is not necessary to reset this before each transfer. +The actual bus frequency may be lower due to hardware limitiations +of the SPI bus controller device. +.It Dv SPIGENIOC_GET_SPI_MODE Pq Vt uint32_t +Get the SPI mode (clock polarity and phase) to be used +when communicating with this device. +.It Dv SPIGENIOC_SET_SPI_MODE Pq Vt uint32_t +Set the SPI mode (clock polarity and phase) to be used +when communicating with this device. +The setting remains in effect for subsequent transfers; it +is not necessary to reset this before each transfer. +.El +.Sh HINTS CONFIGURATION +On a +.Xr device.hints 5 +based system, such as +.Li MIPS , +these values are configurable for +.Nm : +.Bl -tag -width indent +.It Va hint.spigen.%d.at +The spibus the +.Nm +instance is attached to. +.It Va hint.spigen.%d.clock +The maximum bus frequency to use when communicating with this device. +Actual bus speed may be lower, depending on the capabilities of the SPI +bus controller hardware. +.It Va hint.spigen.%d.cs +The chip-select number to assert when performing I/O for this device. +Set the high bit (1 << 31) to invert the logic level of the chip select line. +.It Va hint.spigen.%d.mode +The SPI mode (0-3) to use when communicating with this device. +.El +.Sh FDT CONFIGURATION +On an +.Xr fdt 4 +based system, the spigen device is defined as a slave device subnode +of the SPI bus controller node. +All properties documented in the +.Va spibus.txt +bindings document can be used with the +.Nm +device. +The most commonly-used ones are documented below. +.Pp +The following properties are required in the +.Nm +device subnode: +.Bl -tag -width indent +.It Va compatible +Must be the string "freebsd,spigen". +.It Va reg +Chip select address of device. +.It Va spi-max-frequency +The maximum bus frequency to use when communicating with this slave device. +Actual bus speed may be lower, depending on the capabilities of the SPI +bus controller hardware. +.El +.Pp +The following properties are optional for the +.Nm +device subnode: +.Bl -tag -width indent +.It Va spi-cpha +Empty property indicating the slave device requires shifted clock +phase (CPHA) mode. +.It Va spi-cpol +Empty property indicating the slave device requires inverse clock +polarity (CPOL) mode. +.It Va spi-cs-high +Empty property indicating the slave device requires chip select active high. +.El +.Sh FILES +.Bl -tag -width -compact +.It Pa /dev/spigen* +.El +.Sh SEE ALSO +.Xr fdt 4 , +.Xr device.hints 5 +.Sh HISTORY +The +.Nm +driver +appeared in +.Fx 11.0 . +FDT support appeared in +.Fx 11.2 . diff --git a/sys/dev/spibus/ofw_spibus.c b/sys/dev/spibus/ofw_spibus.c index c89db2c..1da3dae 100644 --- a/sys/dev/spibus/ofw_spibus.c +++ b/sys/dev/spibus/ofw_spibus.c @@ -69,7 +69,7 @@ ofw_spibus_probe(device_t dev) return (ENXIO); device_set_desc(dev, "OFW SPI bus"); - return (0); + return (BUS_PROBE_DEFAULT); } static int @@ -105,6 +105,10 @@ ofw_spibus_attach(device_t dev) /* * Get the maximum clock frequency for device, zero means * use the default bus speed. + * + * XXX Note that the current (2018-04-07) dts bindings say that + * spi-max-frequency is a required property (but says nothing of + * how to interpret a value of zero). */ if (OF_getencprop(child, "spi-max-frequency", &clock, sizeof(clock)) == -1) diff --git a/sys/dev/spibus/spibus.c b/sys/dev/spibus/spibus.c index 3c6a631..ec3739b 100644 --- a/sys/dev/spibus/spibus.c +++ b/sys/dev/spibus/spibus.c @@ -49,8 +49,9 @@ __FBSDID("$FreeBSD$"); static int spibus_probe(device_t dev) { - device_set_desc(dev, "spibus bus"); - return (BUS_PROBE_GENERIC); + + device_set_desc(dev, "SPI bus"); + return (BUS_PROBE_DEFAULT); } static int @@ -70,16 +71,11 @@ spibus_attach(device_t dev) static int spibus_detach(device_t dev) { - int err, ndevs, i; - device_t *devlist; + int err; if ((err = bus_generic_detach(dev)) != 0) return (err); - if ((err = device_get_children(dev, &devlist, &ndevs)) != 0) - return (err); - for (i = 0; i < ndevs; i++) - device_delete_child(dev, devlist[i]); - free(devlist, M_TEMP); + device_delete_children(dev); return (0); } @@ -160,6 +156,37 @@ spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result) return (0); } +static int +spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value) +{ + struct spibus_ivar *devi = SPIBUS_IVAR(child); + + if (devi == NULL || device_get_parent(child) != bus) + return (EDOOFUS); + + switch (which) { + case SPIBUS_IVAR_CLOCK: + /* Any non-zero value is allowed for max clock frequency. */ + if (value == 0) + return (EINVAL); + devi->clock = (uint32_t)value; + break; + case SPIBUS_IVAR_CS: + /* Chip select cannot be changed. */ + return (EINVAL); + case SPIBUS_IVAR_MODE: + /* Valid SPI modes are 0-3. */ + if (value > 3) + return (EINVAL); + devi->mode = (uint32_t)value; + break; + default: + return (EINVAL); + } + + return (0); +} + static device_t spibus_add_child(device_t dev, u_int order, const char *name, int unit) { @@ -211,6 +238,7 @@ static device_method_t spibus_methods[] = { DEVMETHOD(bus_print_child, spibus_print_child), DEVMETHOD(bus_probe_nomatch, spibus_probe_nomatch), DEVMETHOD(bus_read_ivar, spibus_read_ivar), + DEVMETHOD(bus_write_ivar, spibus_write_ivar), DEVMETHOD(bus_child_pnpinfo_str, spibus_child_pnpinfo_str), DEVMETHOD(bus_child_location_str, spibus_child_location_str), DEVMETHOD(bus_hinted_child, spibus_hinted_child), diff --git a/sys/dev/spibus/spibusvar.h b/sys/dev/spibus/spibusvar.h index 15f9049..ffa016a 100644 --- a/sys/dev/spibus/spibusvar.h +++ b/sys/dev/spibus/spibusvar.h @@ -60,8 +60,14 @@ spibus_get_ ## A(device_t dev, T *t) \ { \ return BUS_READ_IVAR(device_get_parent(dev), dev, \ SPIBUS_IVAR_ ## B, (uintptr_t *) t); \ +} \ +static inline int \ +spibus_set_ ## A(device_t dev, T t) \ +{ \ + return BUS_WRITE_IVAR(device_get_parent(dev), dev, \ + SPIBUS_IVAR_ ## B, (uintptr_t) t); \ } - + SPIBUS_ACCESSOR(cs, CS, uint32_t) SPIBUS_ACCESSOR(mode, MODE, uint32_t) SPIBUS_ACCESSOR(clock, CLOCK, uint32_t) diff --git a/sys/dev/spibus/spigen.c b/sys/dev/spibus/spigen.c index 0432dce..46920b3 100644 --- a/sys/dev/spibus/spigen.c +++ b/sys/dev/spibus/spigen.c @@ -50,6 +50,11 @@ __FBSDID("$FreeBSD$"); #include <vm/vm_pager.h> #include <dev/spibus/spi.h> +#include <dev/spibus/spibusvar.h> + +#ifdef FDT +#include <dev/ofw/ofw_bus_subr.h> +#endif #include "spibus_if.h" @@ -60,7 +65,6 @@ struct spigen_softc { device_t sc_dev; struct cdev *sc_cdev; struct mtx sc_mtx; - uint32_t sc_clock_speed; uint32_t sc_command_length_max; /* cannot change while mmapped */ uint32_t sc_data_length_max; /* cannot change while mmapped */ vm_object_t sc_mmap_buffer; /* command, then data */ @@ -70,24 +74,27 @@ struct spigen_softc { int sc_flags; }; -#ifdef FDT -static void -spigen_identify(driver_t *driver, device_t parent) -{ - if (device_find_child(parent, "spigen", -1) != NULL) - return; - if (BUS_ADD_CHILD(parent, 0, "spigen", -1) == NULL) - device_printf(parent, "add child failed\n"); -} -#endif - static int spigen_probe(device_t dev) { + int rv; + + /* + * By default we only bid to attach if specifically added by our parent + * (usually via hint.spigen.#.at=busname). On FDT systems we bid as the + * default driver based on being configured in the FDT data. + */ + rv = BUS_PROBE_NOWILDCARD; + +#ifdef FDT + if (ofw_bus_status_okay(dev) && + ofw_bus_is_compatible(dev, "freebsd,spigen")) + rv = BUS_PROBE_DEFAULT; +#endif device_set_desc(dev, "SPI Generic IO"); - return (BUS_PROBE_NOWILDCARD); + return (rv); } static int spigen_open(struct cdev *, int, int, struct thread *); @@ -238,15 +245,9 @@ spigen_transfer(struct cdev *cdev, struct spigen_transfer *st) #endif transfer.tx_cmd = transfer.rx_cmd = malloc(st->st_command.iov_len, M_DEVBUF, M_WAITOK); - if (transfer.tx_cmd == NULL) - return (ENOMEM); if (st->st_data.iov_len > 0) { transfer.tx_data = transfer.rx_data = malloc(st->st_data.iov_len, M_DEVBUF, M_WAITOK); - if (transfer.tx_data == NULL) { - free(transfer.tx_cmd, M_DEVBUF); - return (ENOMEM); - } } else transfer.tx_data = transfer.rx_data = NULL; @@ -316,7 +317,6 @@ spigen_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, struct thread *td) { device_t dev = cdev->si_drv1; - struct spigen_softc *sc = device_get_softc(dev); int error; switch (cmd) { @@ -327,20 +327,20 @@ spigen_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, error = spigen_transfer_mmapped(cdev, (struct spigen_transfer_mmapped *)data); break; case SPIGENIOC_GET_CLOCK_SPEED: - mtx_lock(&sc->sc_mtx); - *(uint32_t *)data = sc->sc_clock_speed; - /* XXX TODO: implement spibus ivar call */ - mtx_unlock(&sc->sc_mtx); - error = 0; + error = spibus_get_clock(dev, (uint32_t *)data); break; case SPIGENIOC_SET_CLOCK_SPEED: - mtx_lock(&sc->sc_mtx); - sc->sc_clock_speed = *(uint32_t *)data; - mtx_unlock(&sc->sc_mtx); - error = 0; + error = spibus_set_clock(dev, *(uint32_t *)data); + break; + case SPIGENIOC_GET_SPI_MODE: + error = spibus_get_mode(dev, (uint32_t *)data); + break; + case SPIGENIOC_SET_SPI_MODE: + error = spibus_set_mode(dev, *(uint32_t *)data); break; default: - error = EOPNOTSUPP; + error = ENOTTY; + break; } return (error); } @@ -439,9 +439,6 @@ static devclass_t spigen_devclass; static device_method_t spigen_methods[] = { /* Device interface */ -#ifdef FDT - DEVMETHOD(device_identify, spigen_identify), -#endif DEVMETHOD(device_probe, spigen_probe), DEVMETHOD(device_attach, spigen_attach), DEVMETHOD(device_detach, spigen_detach), @@ -456,3 +453,4 @@ static driver_t spigen_driver = { }; DRIVER_MODULE(spigen, spibus, spigen_driver, spigen_devclass, 0, 0); +MODULE_DEPEND(spigen, spibus, 1, 1, 1); diff --git a/sys/modules/spigen/Makefile b/sys/modules/spigen/Makefile index f60e117..5a0c8c6 100644 --- a/sys/modules/spigen/Makefile +++ b/sys/modules/spigen/Makefile @@ -3,6 +3,16 @@ .PATH: ${SRCTOP}/sys/dev/spibus KMOD= spigen SRCS= spigen.c -SRCS+= device_if.h bus_if.h opt_platform.h spibus_if.h + +# Generated files... +SRCS+= \ + bus_if.h \ + device_if.h \ + opt_platform.h \ + spibus_if.h \ + +.if !empty(OPT_FDT) +SRCS+= ofw_bus_if.h +.endif .include <bsd.kmod.mk> diff --git a/sys/sys/spigenio.h b/sys/sys/spigenio.h index 9e3ee90..d0bab29 100644 --- a/sys/sys/spigenio.h +++ b/sys/sys/spigenio.h @@ -48,5 +48,7 @@ struct spigen_transfer_mmapped { struct spigen_transfer_mmapped) #define SPIGENIOC_GET_CLOCK_SPEED _IOR(SPIGENIOC_BASE, 2, uint32_t) #define SPIGENIOC_SET_CLOCK_SPEED _IOW(SPIGENIOC_BASE, 3, uint32_t) +#define SPIGENIOC_GET_SPI_MODE _IOR(SPIGENIOC_BASE, 4, uint32_t) +#define SPIGENIOC_SET_SPI_MODE _IOW(SPIGENIOC_BASE, 5, uint32_t) #endif /* !_SYS_SPIGENIO_H_ */ |
