diff options
| author |   Christian Eggers <ceggers@arri.de> | 2020-10-09 13:03:19 +0200 |
|---|---|---|
| committer |   Wolfram Sang <wsa@kernel.org> | 2020-12-02 21:28:20 +0100 |
| commit | 1de67a3dee7a279ebe4d892b359fe3696938ec15 (patch) | |
| tree | 77db1ed346aa4ed5548b2235951f92f09024a6a0 /drivers/i2c | |
| parent | i2c: imx: Fix reset of I2SR_IAL flag (diff) | |
| download | linux-dev-1de67a3dee7a279ebe4d892b359fe3696938ec15.tar.xz linux-dev-1de67a3dee7a279ebe4d892b359fe3696938ec15.zip | |
i2c: imx: Check for I2SR_IAL after every byte
Arbitration Lost (IAL) can happen after every single byte transfer. If
arbitration is lost, the I2C hardware will autonomously switch from
master mode to slave. If a transfer is not aborted in this state,
consecutive transfers will not be executed by the hardware and will
timeout.
Signed-off-by: Christian Eggers <ceggers@arri.de>
Tested (not extensively) on Vybrid VF500 (Toradex VF50):
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-imx.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 39e98d216016..a2abae124342 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -490,6 +490,16 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic) dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); return -ETIMEDOUT; } + + /* check for arbitration lost */ + if (i2c_imx->i2csr & I2SR_IAL) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + + i2c_imx->i2csr = 0; + return -EAGAIN; + } + dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); i2c_imx->i2csr = 0; return 0; |