Support SPI minor devices >255 (PR #33)

host/bbb/bbb.go

@@ -95,7 +95,7 @@ var ledMap = embd.LEDMap{
 	"beaglebone:green:usr3": []string{"3", "USR3", "usr3"},
 }
 
-var spiDeviceMinor byte = 1
+var spiDeviceMinor int = 1
 
 func ensureFeatureEnabled(id string) error {
 	glog.V(3).Infof("bbb: enabling feature %v", id)

host/chip/chip.go

@@ -18,7 +18,7 @@ import (
 	"github.com/kidoman/embd/host/generic"
 )
 
-var spiDeviceMinor = byte(0)
+var spiDeviceMinor = 32766
 
 var chipPins = embd.PinMap{
 	// official GPIO pins (U14 connector) using the pcf8574a

host/generic/i2cbus.go

@@ -245,7 +245,7 @@ func (b *i2cBus) WriteToReg(addr, reg byte, value []byte) error {
 	message.addr = uint16(addr)
 	message.flags = 0
 	message.len = uint16(len(outbuf))
-	message.buf = uintptr(unsafe.Pointer(&hdrp.Data))
+	message.buf = uintptr(unsafe.Pointer(hdrp.Data))
 
 	var packets i2c_rdwr_ioctl_data
 

host/generic/spibus.go

@@ -43,7 +43,7 @@ type spiIOCTransfer struct {
 type spiBus struct {
 	file *os.File
 
-	spiDevMinor byte
+	spiDevMinor int
 
 	channel byte
 	mode    byte
@@ -63,7 +63,7 @@ func spiIOCMessageN(n uint32) uint32 {
 	return (spiIOCMessage0 + (n * spiIOCIncrementor))
 }
 
-func NewSPIBus(spiDevMinor, mode, channel byte, speed, bpw, delay int, i func() error) embd.SPIBus {
+func NewSPIBus(spiDevMinor int, mode, channel byte, speed, bpw, delay int, i func() error) embd.SPIBus {
 	return &spiBus{
 		spiDevMinor: spiDevMinor,
 		mode:        mode,

host/rpi/rpi.go

@@ -13,7 +13,7 @@ import (
 	"github.com/kidoman/embd/host/generic"
 )
 
-var spiDeviceMinor = byte(0)
+var spiDeviceMinor = 0
 
 var rev1Pins = embd.PinMap{
 	&embd.PinDesc{ID: "P1_3", Aliases: []string{"0", "GPIO_0", "SDA", "I2C0_SDA"}, Caps: embd.CapDigital | embd.CapI2C, DigitalLogical: 0},

spidriver.go

@@ -2,10 +2,10 @@ package embd
 
 import "sync"
 
-type spiBusFactory func(byte, byte, byte, int, int, int, func() error) SPIBus
+type spiBusFactory func(int, byte, byte, int, int, int, func() error) SPIBus
 
 type spiDriver struct {
-	spiDevMinor byte
+	spiDevMinor int
 	initializer func() error
 
 	busMap     map[byte]SPIBus
@@ -16,7 +16,7 @@ type spiDriver struct {
 
 // NewSPIDriver returns a SPIDriver interface which allows control
 // over the SPI bus.
-func NewSPIDriver(spiDevMinor byte, sbf spiBusFactory, i func() error) SPIDriver {
+func NewSPIDriver(spiDevMinor int, sbf spiBusFactory, i func() error) SPIDriver {
 	return &spiDriver{
 		spiDevMinor: spiDevMinor,
 		sbf:         sbf,