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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Tali Perry <tali.perry1@gmail.com>,
        Tyrone Ting <kfting@nuvoton.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Wolfram Sang <wsa@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.15 251/779] i2c: npcm: Correct slave role behavior
Date:   Mon, 15 Aug 2022 19:58:15 +0200
Message-Id: <20220815180348.061466377@linuxfoundation.org>
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From: Tali Perry <tali.perry1@gmail.com>

[ Upstream commit d7aa1b149b8fc04d802879cf4662010aa4a42deb ]

Correct the slave transaction logic to be compatible with the generic
slave backend driver.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index ab31e7fb4cc9..31e3d2c9d6bc 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -912,11 +912,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
 		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
 			break;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+		if (bus->state == I2C_SLAVE_MATCH) {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+			bus->state = I2C_OPER_STARTED;
+		} else {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
+		}
 		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
 		bus->slv_wr_buf[ind] = value;
 		bus->slv_wr_size++;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
 	}
 	return I2C_HW_FIFO_SIZE - ret;
 }
@@ -964,7 +968,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
 	if (nwrite == 0)
 		return;
 
-	bus->state = I2C_OPER_STARTED;
 	bus->operation = I2C_WRITE_OPER;
 
 	/* get the next buffer */
-- 
2.35.1