diff options
| author | Robert Jarzmik <robert.jarzmik@free.fr> | 2009-04-21 20:34:44 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-06-15 21:44:42 -0700 |
| commit | 9f5351b743716c796d13235651699fb4ec7aa64f (patch) | |
| tree | d8cfe409a56f89e3753fd6f82cd38beddb3d4244 /drivers/usb/gadget/pxa27x_udc.c | |
| parent | f6d529f936672d341fab14ffb0d8eebeee2d8cd3 (diff) | |
USB: pxa27x_udc: compatibility with pxa320 SoC
Got pxa27x_udc working on the pxa320 Nomad platform. The
problem was that the pxa3xx UDC is not quite compatible with
the pxa27x UDC in how it handles back-to-back control
packets. The pxa27x probably drops them by default, but the
pxa320 does not, and you have to detect it and set the OPC
bit to clear the zero-length packet.
Signed-off-by: Aric Blumer <aric@sdgsystems.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/gadget/pxa27x_udc.c')
| -rw-r--r-- | drivers/usb/gadget/pxa27x_udc.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/usb/gadget/pxa27x_udc.c b/drivers/usb/gadget/pxa27x_udc.c index ffe6e0afc2e..51790b06b8c 100644 --- a/drivers/usb/gadget/pxa27x_udc.c +++ b/drivers/usb/gadget/pxa27x_udc.c @@ -1892,6 +1892,15 @@ static void handle_ep0_ctrl_req(struct pxa_udc *udc, nuke(ep, -EPROTO); + /* + * In the PXA320 manual, in the section about Back-to-Back setup + * packets, it describes this situation. The solution is to set OPC to + * get rid of the status packet, and then continue with the setup + * packet. Generalize to pxa27x CPUs. + */ + if (epout_has_pkt(ep) && (ep_count_bytes_remain(ep) == 0)) + udc_ep_writel(ep, UDCCSR, UDCCSR0_OPC); + /* read SETUP packet */ for (i = 0; i < 2; i++) { if (unlikely(ep_is_empty(ep))) @@ -1965,6 +1974,8 @@ stall: * cleared by software. * - clearing UDCCSR0_OPC always flushes ep0. If in setup stage, never do it * before reading ep0. + * This is true only for PXA27x. This is not true anymore for PXA3xx family + * (check Back-to-Back setup packet in developers guide). * - irq can be called on a "packet complete" event (opc_irq=1), while * UDCCSR0_OPC is not yet raised (delta can be as big as 100ms * from experimentation). @@ -2575,7 +2586,7 @@ static struct platform_driver udc_driver = { static int __init udc_init(void) { - if (!cpu_is_pxa27x()) + if (!cpu_is_pxa27x() && !cpu_is_pxa3xx()) return -ENODEV; printk(KERN_INFO "%s: version %s\n", driver_name, DRIVER_VERSION); |