openwrt/target/linux/generic/backport-5.4/820-v5.8-i2c-pxa-use-master-abort-for-device-probes.patch

From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 6/7] i2c: pxa: use master-abort for device probes
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Use master-abort to send the stop condition after an address cycle
rather than resetting the controller.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/i2c/busses/i2c-pxa.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -899,14 +899,8 @@ static void i2c_pxa_irq_txempty(struct p
 		icr &= ~ICR_ALDIE;
 		icr |= ICR_START | ICR_TB;
 	} else {
-		if (i2c->msg->len == 0) {
-			/*
-			 * Device probes have a message length of zero
-			 * and need the bus to be reset before it can
-			 * be used again.
-			 */
-			i2c_pxa_reset(i2c);
-		}
+		if (i2c->msg->len == 0)
+			icr |= ICR_MA;
 		i2c_pxa_master_complete(i2c, 0);
 	}