From: Yicong Yang yangyicong@hisilicon.com
[ Upstream commit cc9812a3096d1986caca9a23bee99effc45c08df ]
After issuing all the messages we can disable the TX_EMPTY interrupts to avoid handling redundant interrupts. For doing a sinlge bus detection (i2cdetect -y -r 0) we can reduce ~97% interrupts (before ~12000 after ~400).
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 | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-hisi.c b/drivers/i2c/busses/i2c-hisi.c index 72e43ecaff133..1f406e6f4ece3 100644 --- a/drivers/i2c/busses/i2c-hisi.c +++ b/drivers/i2c/busses/i2c-hisi.c @@ -315,6 +315,13 @@ static void hisi_i2c_xfer_msg(struct hisi_i2c_controller *ctlr) max_write == 0) break; } + + /* + * Disable the TX_EMPTY interrupt after finishing all the messages to + * avoid overwhelming the CPU. + */ + if (ctlr->msg_tx_idx == ctlr->msg_num) + hisi_i2c_disable_int(ctlr, HISI_I2C_INT_TX_EMPTY); }
static irqreturn_t hisi_i2c_irq(int irq, void *context)