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usb_control: Mark the control pipe as IDLE after a STALL

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After a STALL handshake is transmitted, a control pipe becomes idle. Not
marking the pipe as idle did not affect the STM32 family. Since it
distinguishes between OUT and SETUP tokens, it calls the setup handler
on a SETUP token, regardless of the state of the pipe.

Other families, such as LM4F do not distinguish in software between IN and
SETUP tokens, and need to decide which handler to call based on the state
of the pipe. On these chips, SETUP transactions will not be handled
properly after a transfer was STALLED, as the state machine of the pipe is
b0rked. Unb0rk it.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
This commit is contained in:
Alexandru Gagniuc 2013-07-06 04:08:05 -05:00 committed by Piotr Esden-Tempski
parent ad29d0ce31
commit 0819a49411
1 changed files with 18 additions and 7 deletions
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25
lib/usb/usb_control.c
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@ -39,6 +39,17 @@ LGPL License Terms @ref lgpl_license
#include <libopencm3/usb/usbd.h>
#include "usb_private.h"
/*
* According to the USB 2.0 specification, section 8.5.3, when a control
* transfer is stalled, the pipe becomes idle. We provide one utility to stall
* a transaction to reduce boilerplate code.
*/
static void stall_transaction(usbd_device *usbd_dev)
{
usbd_ep_stall_set(usbd_dev, 0, 1);
usbd_dev->control_state.state = IDLE;
}
/* Register application callback function for handling USB control requests. */
int usbd_register_control_callback(usbd_device *usbd_dev, uint8_t type,
uint8_t type_mask,
@ -95,7 +106,7 @@ static int usb_control_recv_chunk(usbd_device *usbd_dev)
packetsize);
if (size != packetsize) {
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
return -1;
}
@ -152,7 +163,7 @@ static void usb_control_setup_read(usbd_device *usbd_dev,
}
} else {
/* Stall endpoint on failure. */
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
}
}
@ -160,7 +171,7 @@ static void usb_control_setup_write(usbd_device *usbd_dev,
struct usb_setup_data *req)
{
if (req->wLength > usbd_dev->ctrl_buf_len) {
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
return;
}
@ -186,7 +197,7 @@ void _usbd_control_setup(usbd_device *usbd_dev, uint8_t ea)
usbd_dev->control_state.complete = NULL;
if (usbd_ep_read_packet(usbd_dev, 0, req, 8) != 8) {
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
return;
}
@ -228,7 +239,7 @@ void _usbd_control_out(usbd_device *usbd_dev, uint8_t ea)
usbd_ep_write_packet(usbd_dev, 0, NULL, 0);
usbd_dev->control_state.state = STATUS_IN;
} else {
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
}
break;
case STATUS_OUT:
@ -241,7 +252,7 @@ void _usbd_control_out(usbd_device *usbd_dev, uint8_t ea)
usbd_dev->control_state.complete = NULL;
break;
default:
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
}
}
@ -271,7 +282,7 @@ void _usbd_control_in(usbd_device *usbd_dev, uint8_t ea)
usbd_dev->control_state.state = IDLE;
break;
default:
usbd_ep_stall_set(usbd_dev, 0, 1);
stall_transaction(usbd_dev);
}
}