From c770657bd2611b077ec1e7b1fe6aa92f249399bd Mon Sep 17 00:00:00 2001 From: Reid Tonking Date: Wed, 26 Apr 2023 14:49:56 -0500 Subject: [PATCH] i2c: omap: Fix standard mode false ACK readings Using standard mode, rare false ACK responses were appearing with i2cdetect tool. This was happening due to NACK interrupt triggering ISR thread before register access interrupt was ready. Removing the NACK interrupt's ability to trigger ISR thread lets register access ready interrupt do this instead. Cc: # v3.7+ Fixes: 3b2f8f82dad7 ("i2c: omap: switch to threaded IRQ support") Signed-off-by: Reid Tonking Acked-by: Vignesh Raghavendra Reviewed-by: Tony Lindgren Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-omap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 2b4e2be..4199f57 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -1058,7 +1058,7 @@ omap_i2c_isr(int irq, void *dev_id) u16 stat; stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); - mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG); + mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG) & ~OMAP_I2C_STAT_NACK; if (stat & mask) ret = IRQ_WAKE_THREAD; -- 2.7.4