From 8d6499e5bde91ad05dea4f666bdfe79e65e7cf96 Mon Sep 17 00:00:00 2001 From: Daniel Glöckner Date: Tue, 17 Nov 2009 15:22:57 +0530 Subject: USB: musb: Fix CPPI IRQs not being signaled On tx channel abort a cppi interrupt is generated for a short time by setting the lowest bit of the TCPPICOMPPTR register. It is then reset immediately by clearing the bit. When the interrupt handler is run, it does not detect an interrupt in the TCPPIMSKSR or RCPPIMSKSR registers and thus exits early without writing the TCPPIEOIR register. It appears that this inhibits further cppi interrupts until the handler is called by chance, f.ex. from davinci_interrupt(). By moving the unmasking of the interrupt below the writes to TCPPICOMPPTR, no interrupt is generated and no write to TCPPIEOIR is necessary. Signed-off-by: Daniel Glöckner Signed-off-by: Ajay Kumar Gupta Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/cppi_dma.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/usb/musb/cppi_dma.c b/drivers/usb/musb/cppi_dma.c index c3577bbbae6c..ef2332a9941d 100644 --- a/drivers/usb/musb/cppi_dma.c +++ b/drivers/usb/musb/cppi_dma.c @@ -1442,11 +1442,6 @@ static int cppi_channel_abort(struct dma_channel *channel) musb_writew(regs, MUSB_TXCSR, value); musb_writew(regs, MUSB_TXCSR, value); - /* re-enable interrupt */ - if (enabled) - musb_writel(tibase, DAVINCI_TXCPPI_INTENAB_REG, - (1 << cppi_ch->index)); - /* While we scrub the TX state RAM, ensure that we clean * up any interrupt that's currently asserted: * 1. Write to completion Ptr value 0x1(bit 0 set) @@ -1459,6 +1454,11 @@ static int cppi_channel_abort(struct dma_channel *channel) cppi_reset_tx(tx_ram, 1); musb_writel(&tx_ram->tx_complete, 0, 0); + /* re-enable interrupt */ + if (enabled) + musb_writel(tibase, DAVINCI_TXCPPI_INTENAB_REG, + (1 << cppi_ch->index)); + cppi_dump_tx(5, cppi_ch, " (done teardown)"); /* REVISIT tx side _should_ clean up the same way -- cgit v1.2.3