From: Yicong Yang yangyicong@hisilicon.com
[ Upstream commit d98263512684a47e81bcb72a5408958ecd1e60b0 ]
The controller will always generate a completion interrupt when the transfer is finished normally or not. Currently we use either error or completion interrupt to finish, this may result the completion interrupt unhandled and corrupt the next transfer, especially at low speed mode. Since on error case, the error interrupt will come first then is the completion interrupt. So only use the completion interrupt to finish the whole transfer process.
Fixes: d62fbdb99a85 ("i2c: add support for HiSilicon I2C controller") Reported-by: Sheng Feng fengsheng5@huawei.com Signed-off-by: Sheng Feng fengsheng5@huawei.com Signed-off-by: Yicong Yang yangyicong@hisilicon.com Signed-off-by: Wolfram Sang wsa@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/busses/i2c-hisi.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-hisi.c b/drivers/i2c/busses/i2c-hisi.c index 76c3d8f6fc3c6..d30071f299879 100644 --- a/drivers/i2c/busses/i2c-hisi.c +++ b/drivers/i2c/busses/i2c-hisi.c @@ -339,7 +339,11 @@ static irqreturn_t hisi_i2c_irq(int irq, void *context) hisi_i2c_read_rx_fifo(ctlr);
out: - if (int_stat & HISI_I2C_INT_TRANS_CPLT || ctlr->xfer_err) { + /* + * Only use TRANS_CPLT to indicate the completion. On error cases we'll + * get two interrupts, INT_ERR first then TRANS_CPLT. + */ + if (int_stat & HISI_I2C_INT_TRANS_CPLT) { hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL); complete(ctlr->completion);