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: <stable@vger.kernel.org> # v3.7+
Fixes: 3b2f8f82dad7 ("i2c: omap: switch to threaded IRQ support")
Signed-off-by: Reid Tonking <reidt@ti.com>
Acked-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Reid Tonking 2023-04-26 14:49:56 -05:00 committed by Wolfram Sang
parent 9f855779a3
commit c770657bd2

View File

@ -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;