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| author | Christian Eggers <ceggers@arri.de> | 2020-10-09 13:03:19 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-12-11 13:25:02 +0100 |
| commit | d614a21c7460e97873ac974d66b866a8e416c8f2 (patch) | |
| tree | 825132ba0e1772f0f5d392423075de2ab57cb385 | |
| parent | 7d4904a1a2523cd2e5ee98c52f09a2fb048ae7b7 (diff) | |
| download | linux-stable-d614a21c7460e97873ac974d66b866a8e416c8f2.tar.gz linux-stable-d614a21c7460e97873ac974d66b866a8e416c8f2.tar.bz2 linux-stable-d614a21c7460e97873ac974d66b866a8e416c8f2.zip | |
i2c: imx: Check for I2SR_IAL after every byte
commit 1de67a3dee7a279ebe4d892b359fe3696938ec15 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 61eceb1809ed..83c246e30399 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -460,6 +460,16 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) 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; |