diff options
authorDaniel Glöckner <dg@emlix.com>2009-11-17 15:22:57 +0530
committerGreg Kroah-Hartman <gregkh@suse.de>2009-11-30 16:43:16 -0800
commit8d6499e5bde91ad05dea4f666bdfe79e65e7cf96 (patch)
parent5542bc2ac7b52c021fc9c7a96329955491b7e763 (diff)
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 <dg@emlix.com> Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/usb/musb/cppi_dma.c b/drivers/usb/musb/cppi_dma.c
index c3577bbbae6..ef2332a9941 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