[PATCH] i2c: tegra: Check for overflow errors with BUG_ON.
From: Felipe Balbi <hidden>
Date: 2011-08-15 19:17:55
Also in:
linux-i2c, linux-tegra, lkml
Hi, On Mon, Aug 15, 2011 at 11:49:32AM -0700, Doug Anderson wrote:
quoted hunk ↗ jump to hunk
This change doesn't fix any known problems but turns on the overflow detection feature of the i2c controller in the hopes of flushing out any current (or future) bugs in the i2c driver. Inspired by a change on nvidia's git server: http://nv-tegra.nvidia.com/gitweb/?p=linux-2.6.git;a=commit;h=266d1b7397284505e55d06254b497cb32be07b69 Signed-off-by: Doug Anderson <dianders@chromium.org> --- drivers/i2c/busses/i2c-tegra.c | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-)diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 2440b74..4dbba23 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c@@ -367,7 +367,8 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) { u32 status; - const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | + I2C_INT_TX_FIFO_OVERFLOW; struct tegra_i2c_dev *i2c_dev = dev_id; status = i2c_readl(i2c_dev, I2C_INT_STATUS);@@ -389,6 +390,9 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) } if (unlikely(status & status_err)) { + /* Don't pass this back--it can only happen due to a bug. */ + BUG_ON(status & I2C_INT_TX_FIFO_OVERFLOW);
so due to a FIFO overflow you lock up the whole system ? Can't you e.g. reset the controller and reconfigure it rather than locking up the system ? -- balbi -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 490 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20110815/34ebb6a6/attachment.sig>