From b18d26f6ad8f00ea5f7c6a12ea52627ca3c3c6e2 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Tue, 30 Oct 2012 19:52:26 +0100 Subject: usb: musb: Perform only write access on MUSB_INTRTXE This is part of the workaround for AM35x advisory Advisory 1.1.20. The advisory says that the IPSS bridge can't handle 8 & 16 bit read access. An 16bit read access to MUSB_INTRTXE results in an 32bit read access which also reads INTRRX and therefore may lose interrupts. This patch uses a shadow register of MUSB_INTRTXE so we only perform write access to it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Felipe Balbi diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 7ff1986..25a0d8e 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -724,7 +724,8 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb, if (is_peripheral_active(musb)) { /* REVISIT HNP; just force disconnect */ } - musb_writew(musb->mregs, MUSB_INTRTXE, musb->epmask); + musb->intrtxe = musb->epmask; + musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe); musb->intrrxe = musb->epmask & 0xfffe; musb_writew(musb->mregs, MUSB_INTRRXE, musb->intrrxe); musb_writeb(musb->mregs, MUSB_INTRUSBE, 0xf7); @@ -947,7 +948,8 @@ void musb_start(struct musb *musb) dev_dbg(musb->controller, "<== devctl %02x\n", devctl); /* Set INT enable registers, enable interrupts */ - musb_writew(regs, MUSB_INTRTXE, musb->epmask); + musb->intrtxe = musb->epmask; + musb_writew(regs, MUSB_INTRTXE, musb->intrtxe); musb->intrrxe = musb->epmask & 0xfffe; musb_writew(regs, MUSB_INTRRXE, musb->intrrxe); musb_writeb(regs, MUSB_INTRUSBE, 0xf7); @@ -987,6 +989,7 @@ static void musb_generic_disable(struct musb *musb) /* disable interrupts */ musb_writeb(mbase, MUSB_INTRUSBE, 0); + musb->intrtxe = 0; musb_writew(mbase, MUSB_INTRTXE, 0); musb->intrrxe = 0; musb_writew(mbase, MUSB_INTRRXE, 0); @@ -2124,7 +2127,6 @@ static void musb_save_context(struct musb *musb) musb->context.testmode = musb_readb(musb_base, MUSB_TESTMODE); musb->context.busctl = musb_read_ulpi_buscontrol(musb->mregs); musb->context.power = musb_readb(musb_base, MUSB_POWER); - musb->context.intrtxe = musb_readw(musb_base, MUSB_INTRTXE); musb->context.intrusbe = musb_readb(musb_base, MUSB_INTRUSBE); musb->context.index = musb_readb(musb_base, MUSB_INDEX); musb->context.devctl = musb_readb(musb_base, MUSB_DEVCTL); @@ -2197,7 +2199,7 @@ static void musb_restore_context(struct musb *musb) musb_writeb(musb_base, MUSB_TESTMODE, musb->context.testmode); musb_write_ulpi_buscontrol(musb->mregs, musb->context.busctl); musb_writeb(musb_base, MUSB_POWER, musb->context.power); - musb_writew(musb_base, MUSB_INTRTXE, musb->context.intrtxe); + musb_writew(musb_base, MUSB_INTRTXE, musb->intrtxe); musb_writew(musb_base, MUSB_INTRRXE, musb->intrrxe); musb_writeb(musb_base, MUSB_INTRUSBE, musb->context.intrusbe); musb_writeb(musb_base, MUSB_DEVCTL, musb->context.devctl); diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h index 60b92cb..0cef3ce 100644 --- a/drivers/usb/musb/musb_core.h +++ b/drivers/usb/musb/musb_core.h @@ -288,7 +288,6 @@ struct musb_csr_regs { struct musb_context_registers { u8 power; - u16 intrtxe; u8 intrusbe; u16 frame; u8 index, testmode; @@ -314,6 +313,7 @@ struct musb { u16 hwvers; u16 intrrxe; + u16 intrtxe; /* this hub status bit is reserved by USB 2.0 and not seen by usbcore */ #define MUSB_PORT_STAT_RESUME (1 << 31) diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index bb684f0..28b9790 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -1068,7 +1068,6 @@ static int musb_gadget_enable(struct usb_ep *ep, */ musb_ep_select(mbase, epnum); if (usb_endpoint_dir_in(desc)) { - u16 int_txe = musb_readw(mbase, MUSB_INTRTXE); if (hw_ep->is_shared_fifo) musb_ep->is_in = 1; @@ -1080,8 +1079,8 @@ static int musb_gadget_enable(struct usb_ep *ep, goto fail; } - int_txe |= (1 << epnum); - musb_writew(mbase, MUSB_INTRTXE, int_txe); + musb->intrtxe |= (1 << epnum); + musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe); /* REVISIT if can_bulk_split(), use by updating "tmp"; * likewise high bandwidth periodic tx @@ -1208,9 +1207,8 @@ static int musb_gadget_disable(struct usb_ep *ep) /* zero the endpoint sizes */ if (musb_ep->is_in) { - u16 int_txe = musb_readw(musb->mregs, MUSB_INTRTXE); - int_txe &= ~(1 << epnum); - musb_writew(musb->mregs, MUSB_INTRTXE, int_txe); + musb->intrtxe &= ~(1 << epnum); + musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe); musb_writew(epio, MUSB_TXMAXP, 0); } else { musb->intrrxe &= ~(1 << epnum); @@ -1530,7 +1528,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep) void __iomem *epio = musb->endpoints[epnum].regs; void __iomem *mbase; unsigned long flags; - u16 csr, int_txe; + u16 csr; mbase = musb->mregs; @@ -1538,8 +1536,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep) musb_ep_select(mbase, (u8) epnum); /* disable interrupts */ - int_txe = musb_readw(mbase, MUSB_INTRTXE); - musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum)); + musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe & ~(1 << epnum)); if (musb_ep->is_in) { csr = musb_readw(epio, MUSB_TXCSR); @@ -1563,7 +1560,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep) } /* re-enable interrupt */ - musb_writew(mbase, MUSB_INTRTXE, int_txe); + musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe); spin_unlock_irqrestore(&musb->lock, flags); } diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c index 3df6a76..e9f0fd9 100644 --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -740,7 +740,7 @@ static void musb_ep_program(struct musb *musb, u8 epnum, csr = musb_readw(epio, MUSB_TXCSR); /* disable interrupt in case we flush */ - int_txe = musb_readw(mbase, MUSB_INTRTXE); + int_txe = musb->intrtxe; musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum)); /* general endpoint setup */ -- cgit v0.10.2