From 1bc2a79a4cde5f703b33342f2fcea8af208614ed Mon Sep 17 00:00:00 2001 From: Sai Pavan Boddu Date: Tue, 1 Mar 2022 09:16:50 +0100 Subject: [PATCH] i2c: i2c-cdns: Start read transaction after write to transfer_size reg Avoid a race condition where read transaction is started keeping expected bytes as 0. Which sometimes would result in sending STOP signal as no data is expected. Observed on QEMU platform. Signed-off-by: Sai Pavan Boddu Reviewed-by: Ashok Reddy Soma Signed-off-by: Michal Simek Link: https://lore.kernel.org/r/487c8026791bfd60719403a2df2c54bb0ae99232.1646122610.git.michal.simek@xilinx.com --- drivers/i2c/i2c-cdns.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-cdns.c b/drivers/i2c/i2c-cdns.c index a650dd69b8..5736afb451 100644 --- a/drivers/i2c/i2c-cdns.c +++ b/drivers/i2c/i2c-cdns.c @@ -375,7 +375,6 @@ static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data, curr_recv_count = recv_count; } } else if (recv_count && !hold_quirk && !curr_recv_count) { - writel(addr, ®s->address); if (recv_count > CDNS_I2C_TRANSFER_SIZE) { writel(CDNS_I2C_TRANSFER_SIZE, ®s->transfer_size); @@ -384,6 +383,7 @@ static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data, writel(recv_count, ®s->transfer_size); curr_recv_count = recv_count; } + writel(addr, ®s->address); } } -- 2.39.5