ili9341: st7735: st7789: unify rotation support

* Unify the Rotation type, so that SetRotation can be used in
    interfaces.
  * Add Rotation() method to these displays, so that the current
    rotation can be read.
  * Change SetRotation() so that it can return an error (if the given
    rotation isn't supported).

displayer.go

@@ -12,3 +12,19 @@ type Displayer interface {
 	// Display sends the buffer (if any) to the screen.
 	Display() error
 }
+
+// Rotation is how much a display has been rotated. Displays can be rotated, and
+// sometimes also mirrored.
+type Rotation uint8
+
+// Clockwise rotation of the screen.
+const (
+	Rotation0 = iota
+	Rotation90
+	Rotation180
+	Rotation270
+	Rotation0Mirror
+	Rotation90Mirror
+	Rotation180Mirror
+	Rotation270Mirror
+)

ili9341/ili9341.go

@@ -5,19 +5,21 @@ import (
 	"image/color"
 	"machine"
 	"time"
+
+	"tinygo.org/x/drivers"
 )
 
 type Config struct {
 	Width            int16
 	Height           int16
-	Rotation         Rotation
+	Rotation         drivers.Rotation
 	DisplayInversion bool
 }
 
 type Device struct {
 	width    int16
 	height   int16
-	rotation Rotation
+	rotation drivers.Rotation
 	driver   driver
 
 	x0, x1 int16 // cached address window; prevents useless/expensive
@@ -262,13 +264,20 @@ func (d *Device) Sleep(sleepEnabled bool) error {
 	return nil
 }
 
-// GetRotation returns the current rotation of the device
+// Rotation returns the current rotation of the device.
-func (d *Device) GetRotation() Rotation {
+func (d *Device) Rotation() drivers.Rotation {
 	return d.rotation
 }
 
-// SetRotation changes the rotation of the device (clock-wise)
+// GetRotation returns the current rotation of the device.
-func (d *Device) SetRotation(rotation Rotation) {
+//
+// Deprecated: use Rotation instead.
+func (d *Device) GetRotation() drivers.Rotation {
+	return d.rotation
+}
+
+// SetRotation changes the rotation of the device (clock-wise).
+func (d *Device) SetRotation(rotation drivers.Rotation) error {
 	madctl := uint8(0)
 	switch rotation % 8 {
 	case Rotation0:
@@ -291,6 +300,7 @@ func (d *Device) SetRotation(rotation Rotation) {
 	cmdBuf[0] = madctl
 	d.sendCommand(MADCTL, cmdBuf[:1])
 	d.rotation = rotation
+	return nil
 }
 
 // SetScrollArea sets an area to scroll with fixed top/bottom or left/right parts of the display

ili9341/registers.go

@@ -1,5 +1,7 @@
 package ili9341
 
+import "tinygo.org/x/drivers"
+
 type Rotation uint8
 
 const (
@@ -77,13 +79,13 @@ const (
 )
 
 const (
-	Rotation0   Rotation = 0
+	Rotation0   = drivers.Rotation0
-	Rotation90  Rotation = 1 // 90 degrees clock-wise rotation
+	Rotation90  = drivers.Rotation90 // 90 degrees clock-wise rotation
-	Rotation180 Rotation = 2
+	Rotation180 = drivers.Rotation180
-	Rotation270 Rotation = 3
+	Rotation270 = drivers.Rotation270
 
-	Rotation0Mirror   Rotation = 4
+	Rotation0Mirror   = drivers.Rotation0Mirror
-	Rotation90Mirror  Rotation = 5
+	Rotation90Mirror  = drivers.Rotation90Mirror
-	Rotation180Mirror Rotation = 6
+	Rotation180Mirror = drivers.Rotation180Mirror
-	Rotation270Mirror Rotation = 7
+	Rotation270Mirror = drivers.Rotation270Mirror
 )

st7735/registers.go

@@ -1,5 +1,7 @@
 package st7735
 
+import "tinygo.org/x/drivers"
+
 // Registers
 const (
 	NOP        = 0x00
@@ -52,8 +54,8 @@ const (
 	GREENTAB   Model = 0
 	MINI80x160 Model = 1
 
-	NO_ROTATION  Rotation = 0
+	NO_ROTATION  = drivers.Rotation0
-	ROTATION_90  Rotation = 1 // 90 degrees clock-wise rotation
+	ROTATION_90  = drivers.Rotation90 // 90 degrees clock-wise rotation
-	ROTATION_180 Rotation = 2
+	ROTATION_180 = drivers.Rotation180
-	ROTATION_270 Rotation = 3
+	ROTATION_270 = drivers.Rotation270
 )

st7735/st7735.go

@@ -14,7 +14,11 @@ import (
 )
 
 type Model uint8
-type Rotation uint8
+
+// Rotation controls the rotation used by the display.
+//
+// Deprecated: use drivers.Rotation instead.
+type Rotation = drivers.Rotation
 
 var (
 	errOutOfBounds = errors.New("rectangle coordinates outside display area")
@@ -31,7 +35,7 @@ type Device struct {
 	height       int16
 	columnOffset int16
 	rowOffset    int16
-	rotation     Rotation
+	rotation     drivers.Rotation
 	batchLength  int16
 	model        Model
 	isBGR        bool
@@ -42,7 +46,7 @@ type Device struct {
 type Config struct {
 	Width        int16
 	Height       int16
-	Rotation     Rotation
+	Rotation     drivers.Rotation
 	Model        Model
 	RowOffset    int16
 	ColumnOffset int16
@@ -215,7 +219,7 @@ func (d *Device) SetPixel(x int16, y int16, c color.RGBA) {
 
 // setWindow prepares the screen to be modified at a given rectangle
 func (d *Device) setWindow(x, y, w, h int16) {
-	if d.rotation == NO_ROTATION || d.rotation == ROTATION_180 {
+	if d.rotation == drivers.Rotation0 || d.rotation == drivers.Rotation180 {
 		x += d.columnOffset
 		y += d.rowOffset
 	} else {
@@ -345,35 +349,38 @@ func (d *Device) DrawFastHLine(x0, x1, y int16, c color.RGBA) {
 
 // FillScreen fills the screen with a given color
 func (d *Device) FillScreen(c color.RGBA) {
-	if d.rotation == NO_ROTATION || d.rotation == ROTATION_180 {
+	if d.rotation == drivers.Rotation0 || d.rotation == drivers.Rotation180 {
 		d.FillRectangle(0, 0, d.width, d.height, c)
 	} else {
 		d.FillRectangle(0, 0, d.height, d.width, c)
 	}
 }
 
+// Rotation returns the currently configured rotation.
+func (d *Device) Rotation() drivers.Rotation {
+	return d.rotation
+}
+
 // SetRotation changes the rotation of the device (clock-wise)
-func (d *Device) SetRotation(rotation Rotation) {
+func (d *Device) SetRotation(rotation drivers.Rotation) error {
+	d.rotation = rotation
 	madctl := uint8(0)
 	switch rotation % 4 {
-	case 0:
+	case drivers.Rotation0:
 		madctl = MADCTL_MX | MADCTL_MY
-		break
+	case drivers.Rotation90:
-	case 1:
 		madctl = MADCTL_MY | MADCTL_MV
-		break
+	case drivers.Rotation180:
-	case 2:
+		// nothing to do
-		break
+	case drivers.Rotation270:
-	case 3:
 		madctl = MADCTL_MX | MADCTL_MV
-		break
 	}
 	if d.isBGR {
 		madctl |= MADCTL_BGR
 	}
 	d.Command(MADCTL)
 	d.Data(madctl)
-
+	return nil
 }
 
 // Command sends a command to the display
@@ -394,7 +401,7 @@ func (d *Device) Tx(data []byte, isCommand bool) {
 
 // Size returns the current size of the display.
 func (d *Device) Size() (w, h int16) {
-	if d.rotation == NO_ROTATION || d.rotation == ROTATION_180 {
+	if d.rotation == drivers.Rotation0 || d.rotation == drivers.Rotation180 {
 		return d.width, d.height
 	}
 	return d.height, d.width

st7789/registers.go

@@ -1,5 +1,7 @@
 package st7789
 
+import "tinygo.org/x/drivers"
+
 // Registers
 const (
 	NOP        = 0x00
@@ -53,10 +55,10 @@ const (
 	VSCRDEF    = 0x33
 	VSCRSADD   = 0x37
 
-	NO_ROTATION  Rotation = 0
+	NO_ROTATION  = drivers.Rotation0
-	ROTATION_90  Rotation = 1 // 90 degrees clock-wise rotation
+	ROTATION_90  = drivers.Rotation90 // 90 degrees clock-wise rotation
-	ROTATION_180 Rotation = 2
+	ROTATION_180 = drivers.Rotation180
-	ROTATION_270 Rotation = 3
+	ROTATION_270 = drivers.Rotation270
 
 	// Allowable frame rate codes for FRCTRL2 (Identifier is in Hz)
 	FRAMERATE_111 FrameRate = 0x01

st7789/st7789.go

@@ -17,7 +17,9 @@ import (
 )
 
 // Rotation controls the rotation used by the display.
-type Rotation uint8
+//
+// Deprecated: use drivers.Rotation instead.
+type Rotation = drivers.Rotation
 
 // FrameRate controls the frame rate used by the display.
 type FrameRate uint8
@@ -39,7 +41,7 @@ type Device struct {
 	rowOffsetCfg    int16
 	columnOffset    int16
 	rowOffset       int16
-	rotation        Rotation
+	rotation        drivers.Rotation
 	frameRate       FrameRate
 	batchLength     int32
 	isBGR           bool
@@ -51,7 +53,7 @@ type Device struct {
 type Config struct {
 	Width        int16
 	Height       int16
-	Rotation     Rotation
+	Rotation     drivers.Rotation
 	RowOffset    int16
 	ColumnOffset int16
 	FrameRate    FrameRate
@@ -251,8 +253,8 @@ func (d *Device) Display() error {
 // SetPixel sets a pixel in the screen
 func (d *Device) SetPixel(x int16, y int16, c color.RGBA) {
 	if x < 0 || y < 0 ||
-		(((d.rotation == NO_ROTATION || d.rotation == ROTATION_180) && (x >= d.width || y >= d.height)) ||
+		(((d.rotation == drivers.Rotation0 || d.rotation == drivers.Rotation180) && (x >= d.width || y >= d.height)) ||
-			((d.rotation == ROTATION_90 || d.rotation == ROTATION_270) && (x >= d.height || y >= d.width))) {
+			((d.rotation == drivers.Rotation90 || d.rotation == drivers.Rotation270) && (x >= d.height || y >= d.width))) {
 		return
 	}
 	d.FillRectangle(x, y, 1, 1, c)
@@ -373,35 +375,37 @@ func (d *Device) FillScreen(c color.RGBA) {
 	}
 }
 
+// Rotation returns the current rotation of the device.
+func (d *Device) Rotation() drivers.Rotation {
+	return d.rotation
+}
+
 // SetRotation changes the rotation of the device (clock-wise)
-func (d *Device) SetRotation(rotation Rotation) {
+func (d *Device) SetRotation(rotation Rotation) error {
 	madctl := uint8(0)
 	switch rotation % 4 {
-	case 0:
+	case drivers.Rotation0:
 		madctl = MADCTL_MX | MADCTL_MY
 		d.rowOffset = d.rowOffsetCfg
 		d.columnOffset = d.columnOffsetCfg
-		break
+	case drivers.Rotation90:
-	case 1:
 		madctl = MADCTL_MY | MADCTL_MV
 		d.rowOffset = d.columnOffsetCfg
 		d.columnOffset = d.rowOffsetCfg
-		break
+	case drivers.Rotation180:
-	case 2:
 		d.rowOffset = 0
 		d.columnOffset = 0
-		break
+	case drivers.Rotation270:
-	case 3:
 		madctl = MADCTL_MX | MADCTL_MV
 		d.rowOffset = 0
 		d.columnOffset = 0
-		break
 	}
 	if d.isBGR {
 		madctl |= MADCTL_BGR
 	}
 	d.Command(MADCTL)
 	d.Data(madctl)
+	return nil
 }
 
 // Command sends a command to the display.
@@ -442,7 +446,7 @@ func (d *Device) Rx(command uint8, data []byte) {
 
 // Size returns the current size of the display.
 func (d *Device) Size() (w, h int16) {
-	if d.rotation == NO_ROTATION || d.rotation == ROTATION_180 {
+	if d.rotation == drivers.Rotation0 || d.rotation == drivers.Rotation180 {
 		return d.width, d.height
 	}
 	return d.height, d.width