altos: Allow USB drivers to skip CDC-ACM -specific descriptors

For devices not providing the standard CDC-ACM interface, let them
skip the various descriptors and interfaces to provide a more limited
set of capabilities.

Signed-off-by: Keith Packard <keithp@keithp.com>

3 files changed, 72 insertions, 21 deletions

diff --git a/src/kernel/ao_product.c b/src/kernel/ao_product.c
index c711a4d2..a1a9af09 100644
--- a/src/kernel/ao_product.c
+++ b/src/kernel/ao_product.c
@@ -33,11 +33,32 @@ const char ao_product[] = AO_iProduct_STRING;
 #define AO_USB_MAX_POWER	100
 #endif
 
-#ifndef AO_USB_INTERFACE_CLASS
-#define AO_USB_INTERFACE_CLASS	0x02
+#ifndef AO_USB_SELF_POWER
+#define AO_USB_SELF_POWER	1
+#endif
+
+#define AO_USB_DEVICE_CLASS_COMMUNICATION	0x02
+#define AO_USB_INTERFACE_CLASS_CONTROL_CDC	0x02
+#define AO_USB_INTERFACE_CLASS_DATA_CDC		0x0A
+
+#ifndef AO_USB_DEVICE_CLASS
+#define AO_USB_DEVICE_CLASS		AO_USB_DEVICE_CLASS_COMMUNICATION
+#endif
+
+#ifndef AO_USB_INTERFACE_CLASS_DATA
+#define AO_USB_INTERFACE_CLASS_CONTROL	AO_USB_INTERFACE_CLASS_CONTROL_CDC
+#define AO_USB_INTERFACE_CLASS_DATA	AO_USB_INTERFACE_CLASS_DATA_CDC
 #endif
 
 #include "ao_usb.h"
+
+#define HEADER_LEN	       	9
+#define CONTROL_CLASS_LEN	35
+#define DATA_LEN		(9 + 7 * AO_USB_HAS_OUT + 7 * AO_USB_HAS_IN)
+
+#define TOTAL_LENGTH		(HEADER_LEN + AO_USB_HAS_INT * CONTROL_CLASS_LEN + DATA_LEN)
+#define NUM_INTERFACES		(AO_USB_HAS_INT + 1)
+
 /* USB descriptors in one giant block of bytes */
 AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 {
@@ -45,7 +66,7 @@ AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 	0x12,
 	AO_USB_DESC_DEVICE,
 	LE_WORD(0x0110),	/*  bcdUSB */
-	0x02,			/*  bDeviceClass */
+	AO_USB_DEVICE_CLASS,	/*  bDeviceClass */
 	0x00,			/*  bDeviceSubClass */
 	0x00,			/*  bDeviceProtocol */
 	AO_USB_CONTROL_SIZE,	/*  bMaxPacketSize */
@@ -60,20 +81,21 @@ AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 	/* Configuration descriptor */
 	0x09,
 	AO_USB_DESC_CONFIGURATION,
-	LE_WORD(67),		/*  wTotalLength */
-	0x02,			/*  bNumInterfaces */
+	LE_WORD(TOTAL_LENGTH),	/*  wTotalLength */
+	NUM_INTERFACES,		/*  bNumInterfaces */
 	0x01,			/*  bConfigurationValue */
 	0x00,			/*  iConfiguration */
-	0xC0,			/*  bmAttributes */
+	0x80 | (AO_USB_SELF_POWER << 6),	/*  bmAttributes */
 	AO_USB_MAX_POWER >> 1,	/*  bMaxPower, 2mA units */
 
+#if AO_USB_HAS_INT
 	/* Control class interface */
 	0x09,
 	AO_USB_DESC_INTERFACE,
 	0x00,			/*  bInterfaceNumber */
 	0x00,			/*  bAlternateSetting */
 	0x01,			/*  bNumEndPoints */
-	AO_USB_INTERFACE_CLASS,	/*  bInterfaceClass */
+	AO_USB_INTERFACE_CLASS_CONTROL,	/*  bInterfaceClass */
 	0x02,			/*  bInterfaceSubClass */
 	0x01,			/*  bInterfaceProtocol, linux requires value of 1 for the cdc_acm module */
 	0x00,			/*  iInterface */
@@ -111,18 +133,20 @@ AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 	0x03,			/* bmAttributes = intr */
 	LE_WORD(8),		/* wMaxPacketSize */
 	0xff,			/* bInterval */
+#endif
 
 	/* Data class interface descriptor */
 	0x09,
 	AO_USB_DESC_INTERFACE,
-	0x01,			/* bInterfaceNumber */
-	0x00,			/* bAlternateSetting */
-	0x02,			/* bNumEndPoints */
-	0x0A,			/* bInterfaceClass = data */
-	0x00,			/* bInterfaceSubClass */
-	0x00,			/* bInterfaceProtocol */
-	0x00,			/* iInterface */
-
+	0x01,				/* bInterfaceNumber */
+	0x00,				/* bAlternateSetting */
+	AO_USB_HAS_OUT + AO_USB_HAS_IN,	/* bNumEndPoints */
+	AO_USB_INTERFACE_CLASS_DATA,	/* bInterfaceClass = data */
+	0x00,				/* bInterfaceSubClass */
+	0x00,				/* bInterfaceProtocol */
+	0x00,				/* iInterface */
+
+#if AO_USB_HAS_OUT
 	/* Data EP OUT */
 	0x07,
 	AO_USB_DESC_ENDPOINT,
@@ -130,7 +154,9 @@ AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 	0x02,			/* bmAttributes = bulk */
 	LE_WORD(AO_USB_OUT_SIZE),/* wMaxPacketSize */
 	0x00,			/* bInterval */
+#endif
 
+#if AO_USB_HAS_IN
 	/* Data EP in */
 	0x07,
 	AO_USB_DESC_ENDPOINT,
@@ -138,6 +164,7 @@ AO_ROMCONFIG_SYMBOL(0x00aa) uint8_t ao_usb_descriptors [] =
 	0x02,			/* bmAttributes = bulk */
 	LE_WORD(AO_USB_IN_SIZE),/* wMaxPacketSize */
 	0x00,			/* bInterval */
+#endif
 
 	/* String descriptors */
 	0x04,
diff --git a/src/kernel/ao_usb.h b/src/kernel/ao_usb.h
index 1ce4f82f..773b5cb7 100644
--- a/src/kernel/ao_usb.h
+++ b/src/kernel/ao_usb.h
@@ -107,6 +107,18 @@ extern __code __at (0x00aa) uint8_t ao_usb_descriptors [];
 #define AO_USB_IN_EP		5
 #endif
 
+#ifndef AO_USB_HAS_OUT
+#define AO_USB_HAS_OUT	1
+#endif
+
+#ifndef AO_USB_HAS_IN
+#define AO_USB_HAS_IN	1
+#endif
+
+#ifndef AO_USB_HAS_INT
+#define AO_USB_HAS_INT	1
+#endif
+
 /*
  * USB bulk packets can only come in 8, 16, 32 and 64
  * byte sizes, so we'll use 64 for everything
diff --git a/src/stmf0/ao_usb_stm.c b/src/stmf0/ao_usb_stm.c
index 691c2d56..b0f4c516 100644
--- a/src/stmf0/ao_usb_stm.c
+++ b/src/stmf0/ao_usb_stm.c
@@ -29,6 +29,10 @@
 #error "must define AO_PA11_PA12_RMP"
 #endif
 
+#ifndef AO_POWER_MANAGEMENT
+#define AO_POWER_MANAGEMENT	0
+#endif
+
 #ifndef USE_USB_STDIO
 #define USE_USB_STDIO	1
 #endif
@@ -397,6 +401,7 @@ ao_usb_set_configuration(void)
 {
 	debug ("ao_usb_set_configuration\n");
 
+#if AO_USB_HAS_INT
 	/* Set up the INT end point */
 	ao_usb_bdt[AO_USB_INT_EPR].single.addr_tx = ao_usb_int_tx_offset;
 	ao_usb_bdt[AO_USB_INT_EPR].single.count_tx = 0;
@@ -406,7 +411,9 @@ ao_usb_set_configuration(void)
 		       STM_USB_EPR_EP_TYPE_INTERRUPT,
 		       STM_USB_EPR_STAT_RX_DISABLED,
 		       STM_USB_EPR_STAT_TX_NAK);
+#endif
 
+#if AO_USB_HAS_OUT
 	/* Set up the OUT end point */
 	ao_usb_bdt[AO_USB_OUT_EPR].single.addr_rx = ao_usb_out_rx_offset;
 	ao_usb_bdt[AO_USB_OUT_EPR].single.count_rx = ((1 << STM_USB_BDT_COUNT_RX_BL_SIZE) |
@@ -417,7 +424,9 @@ ao_usb_set_configuration(void)
 		       STM_USB_EPR_EP_TYPE_BULK,
 		       STM_USB_EPR_STAT_RX_VALID,
 		       STM_USB_EPR_STAT_TX_DISABLED);
+#endif
 
+#if AO_USB_HAS_IN
 	/* Set up the IN end point */
 	ao_usb_bdt[AO_USB_IN_EPR].single.addr_tx = ao_usb_in_tx_offset;
 	ao_usb_bdt[AO_USB_IN_EPR].single.count_tx = 0;
@@ -427,6 +436,7 @@ ao_usb_set_configuration(void)
 		       STM_USB_EPR_EP_TYPE_BULK,
 		       STM_USB_EPR_STAT_RX_DISABLED,
 		       STM_USB_EPR_STAT_TX_NAK);
+#endif
 
 	ao_usb_running = 1;
 #if AO_USB_DIRECTIO
@@ -439,7 +449,6 @@ static uint16_t int_count;
 static uint16_t	in_count;
 static uint16_t	out_count;
 static uint16_t	reset_count;
-static uint16_t suspend_count;
 
 /* The USB memory must be accessed in 16-bit units
  */
@@ -718,6 +727,7 @@ ao_usb_ep0_handle(uint8_t receive)
 	}
 }
 
+#if AO_POWER_MANAGEMENT
 void
 ao_usb_suspend(void)
 {
@@ -734,6 +744,7 @@ ao_usb_wakeup(void)
 	stm_usb.cntr &= ~(1 << STM_USB_CNTR_FSUSP);
 	ao_power_resume();
 }
+#endif
 
 void
 stm_usb_isr(void)
@@ -801,8 +812,8 @@ stm_usb_isr(void)
 		debug ("\treset\n");
 		ao_usb_set_ep0();
 	}
+#if AO_POWER_MANAGEMENT
 	if (istr & (1 << STM_USB_ISTR_SUSP)) {
-		++suspend_count;
 		debug ("\tsuspend\n");
 		ao_usb_suspend();
 	}
@@ -810,6 +821,7 @@ stm_usb_isr(void)
 		debug ("\twakeup\n");
 		ao_usb_wakeup();
 	}
+#endif
 }
 
 /* Queue the current IN buffer for transmission */
@@ -1072,8 +1084,8 @@ ao_usb_enable(void)
 	stm_usb.cntr = ((1 << STM_USB_CNTR_CTRM) |
 			(0 << STM_USB_CNTR_PMAOVRM) |
 			(0 << STM_USB_CNTR_ERRM) |
-			(1 << STM_USB_CNTR_WKUPM) |
-			(1 << STM_USB_CNTR_SUSPM) |
+			(AO_POWER_MANAGEMENT << STM_USB_CNTR_WKUPM) |
+			(AO_POWER_MANAGEMENT << STM_USB_CNTR_SUSPM) |
 			(1 << STM_USB_CNTR_RESETM) |
 			(0 << STM_USB_CNTR_SOFM) |
 			(0 << STM_USB_CNTR_ESOFM) |
@@ -1112,8 +1124,8 @@ ao_usb_echo(void)
 static void
 ao_usb_irq(void)
 {
-	printf ("control: %d out: %d in: %d int: %d reset: %d suspend %d\n",
-		control_count, out_count, in_count, int_count, reset_count, suspend_count);
+	printf ("control: %d out: %d in: %d int: %d reset: %d\n",
+		control_count, out_count, in_count, int_count, reset_count);
 }
 
 __code struct ao_cmds ao_usb_cmds[] = {