libpayload: usbmsc: Factor out usb_msc_force_init() function

We're planning to have a use case with a custom USB device that
implements the USB mass storage protocol on its bulk endpoints, but does
not have the normal MSC class/protocol interface descriptors and does
not support class-specific control requests (Get Max LUN and Bulk-Only
Reset). We'd like to identify/enumerate the device via
usb_generic_create() in our payload but then reuse all the normal MSC
driver code. In order to make that possible, this patch factors a new
usb_msc_force_init() function out of usb_msc_init() which will
initialize an MSC device without checking its descriptors. It also adds
some "quirks" flags that allow devices registered this way to customize
behavior of the MSC stack.

Change-Id: I50392128409cb2a879954f234149a5e3b060a229
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34227
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
This commit is contained in:
Julius Werner 2019-07-10 15:53:59 -07:00 committed by Patrick Georgi
parent 182fea717e
commit 277498c283
2 changed files with 35 additions and 10 deletions

View File

@ -157,6 +157,9 @@ reset_transport (usbdev_t *dev)
dr.wIndex = 0; dr.wIndex = 0;
dr.wLength = 0; dr.wLength = 0;
if (MSC_INST (dev)->quirks & USB_MSC_QUIRK_NO_RESET)
return MSC_COMMAND_FAIL;
/* if any of these fails, detach device, as we are lost */ /* if any of these fails, detach device, as we are lost */
if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0 || if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0 ||
clear_stall (MSC_INST (dev)->bulk_in) || clear_stall (MSC_INST (dev)->bulk_in) ||
@ -185,7 +188,8 @@ initialize_luns (usbdev_t *dev)
dr.wValue = 0; dr.wValue = 0;
dr.wIndex = 0; dr.wIndex = 0;
dr.wLength = 1; dr.wLength = 1;
if (dev->controller->control (dev, IN, sizeof (dr), &dr, if (MSC_INST (dev)->quirks & USB_MSC_QUIRK_NO_LUNS ||
dev->controller->control (dev, IN, sizeof (dr), &dr,
sizeof (msc->num_luns), &msc->num_luns) < 0) sizeof (msc->num_luns), &msc->num_luns) < 0)
msc->num_luns = 0; /* assume only 1 lun if req fails */ msc->num_luns = 0; /* assume only 1 lun if req fails */
msc->num_luns++; /* Get Max LUN returns number of last LUN */ msc->num_luns++; /* Get Max LUN returns number of last LUN */
@ -600,14 +604,6 @@ usb_msc_test_unit_ready (usbdev_t *dev)
void void
usb_msc_init (usbdev_t *dev) usb_msc_init (usbdev_t *dev)
{ {
int i;
/* init .data before setting .destroy */
dev->data = NULL;
dev->destroy = usb_msc_destroy;
dev->poll = usb_msc_poll;
configuration_descriptor_t *cd = configuration_descriptor_t *cd =
(configuration_descriptor_t *) dev->configuration; (configuration_descriptor_t *) dev->configuration;
interface_descriptor_t *interface = interface_descriptor_t *interface =
@ -634,6 +630,19 @@ usb_msc_init (usbdev_t *dev)
return; return;
} }
usb_msc_force_init (dev, 0);
}
void usb_msc_force_init (usbdev_t *dev, u32 quirks)
{
int i;
/* init .data before setting .destroy */
dev->data = NULL;
dev->destroy = usb_msc_destroy;
dev->poll = usb_msc_poll;
dev->data = malloc (sizeof (usbmsc_inst_t)); dev->data = malloc (sizeof (usbmsc_inst_t));
if (!dev->data) if (!dev->data)
fatal("Not enough memory for USB MSC device.\n"); fatal("Not enough memory for USB MSC device.\n");
@ -641,6 +650,7 @@ usb_msc_init (usbdev_t *dev)
MSC_INST (dev)->bulk_in = 0; MSC_INST (dev)->bulk_in = 0;
MSC_INST (dev)->bulk_out = 0; MSC_INST (dev)->bulk_out = 0;
MSC_INST (dev)->usbdisk_created = 0; MSC_INST (dev)->usbdisk_created = 0;
MSC_INST (dev)->quirks = quirks;
for (i = 1; i <= dev->num_endp; i++) { for (i = 1; i <= dev->num_endp; i++) {
if (dev->endpoints[i].endpoint == 0) if (dev->endpoints[i].endpoint == 0)

View File

@ -34,13 +34,24 @@ typedef struct {
unsigned int numblocks; unsigned int numblocks;
endpoint_t *bulk_in; endpoint_t *bulk_in;
endpoint_t *bulk_out; endpoint_t *bulk_out;
u8 usbdisk_created; u8 quirks : 7;
u8 usbdisk_created : 1;
s8 ready; s8 ready;
u8 lun; u8 lun;
u8 num_luns; u8 num_luns;
void *data; /* For use by consumers of libpayload. */ void *data; /* For use by consumers of libpayload. */
} usbmsc_inst_t; } usbmsc_inst_t;
/* Possible values for quirks field. */
enum {
/* Don't check for LUNs (force assumption that there's only one LUN). */
USB_MSC_QUIRK_NO_LUNS = 1 << 0,
/* Never do a BULK_ONLY reset, just continue. This means that the device
cannot recover from phase errors and won't detach automatically for
unrecoverable errors. Do not use unless you have to. */
USB_MSC_QUIRK_NO_RESET = 1 << 1,
};
/* Possible values for ready field. */ /* Possible values for ready field. */
enum { enum {
USB_MSC_DETACHED = -1, /* Disk detached or out to lunch. */ USB_MSC_DETACHED = -1, /* Disk detached or out to lunch. */
@ -56,4 +67,8 @@ typedef enum { cbw_direction_data_in = 0x80, cbw_direction_data_out = 0
int readwrite_blocks_512 (usbdev_t *dev, int start, int n, cbw_direction dir, u8 *buf); int readwrite_blocks_512 (usbdev_t *dev, int start, int n, cbw_direction dir, u8 *buf);
int readwrite_blocks (usbdev_t *dev, int start, int n, cbw_direction dir, u8 *buf); int readwrite_blocks (usbdev_t *dev, int start, int n, cbw_direction dir, u8 *buf);
/* Force a device to enumerate as MSC, without checking class/protocol types.
It must still have a bulk endpoint pair and respond to MSC commands. */
void usb_msc_force_init (usbdev_t *dev, u32 quirks);
#endif #endif