From 64bc0110f1ec905b1676b5ef60c1cc5b1799e1b6 Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Wed, 3 Sep 2014 13:44:25 -0700 Subject: spi/rockchip: Fix the wait_for_idle() timeout The wait_for_idle() could get unlucky and timeout too quickly. Specifically, the old calculation was effectively: timeout = jiffies + 1; if (jiffies >= timeout) print warning; From the above it should be obvious that if jiffies ticks in just the wrong place then we'll have an effective timeout of 0. Fix this by effectively changing the above ">=" to a ">". That gives us an extra jiffy to finish. Signed-off-by: Doug Anderson Signed-off-by: Mark Brown --- drivers/spi/spi-rockchip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/spi/spi-rockchip.c') diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index c0743604b906..2a31bc2d3fd3 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -220,7 +220,7 @@ static inline void wait_for_idle(struct rockchip_spi *rs) do { if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)) return; - } while (time_before(jiffies, timeout)); + } while (!time_after(jiffies, timeout)); dev_warn(rs->dev, "spi controller is in busy state!\n"); } -- cgit From 62946172c81578477fcbb26478aebaa31353488d Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Wed, 3 Sep 2014 13:44:26 -0700 Subject: spi/rockchip: Don't warn if SPI is busy but disabled The reference manual from Rockchip claims this about the BSF (SPI Busy Flag): * 0 - SPI is idle or disabled * 1 - SPI is actively transferring data The above doesn't quite appear to be true. Specifically I found the busy bit set when SPI was disabled. Let's change the WARN_ON() so we only check the busy bit if the controller was enabled. Signed-off-by: Doug Anderson Signed-off-by: Mark Brown --- drivers/spi/spi-rockchip.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/spi/spi-rockchip.c') diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 2a31bc2d3fd3..514f8e73b8e1 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -529,7 +529,8 @@ static int rockchip_spi_transfer_one( int ret = 0; struct rockchip_spi *rs = spi_master_get_devdata(master); - WARN_ON((readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)); + WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) && + (readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)); if (!xfer->tx_buf && !xfer->rx_buf) { dev_err(rs->dev, "No buffer for transfer\n"); -- cgit