Blob Blame History Raw
From: Mikko Perttunen <mperttunen@nvidia.com>
Date: Mon, 11 Jan 2021 18:08:32 +0200
Subject: i2c: tegra: Wait for config load atomically while in ISR

Git-commit: 27b7c6e096264cc7b91bb80a4f65f8c0a66f079f
Patch-mainline: v5.11-rc5
References: bsc#1184386

Upon a communication error, the interrupt handler can call
tegra_i2c_disable_packet_mode. This causes a sleeping poll to happen
unless the current transaction was marked atomic. Fix this by
making the poll happen atomically if we are in an IRQ.

This matches the behavior prior to the patch mentioned
in the Fixes tag.

Fixes: ede2299f7101 ("i2c: tegra: Support atomic transfers")
Cc: stable@vger.kernel.org
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
 drivers/i2c/busses/i2c-tegra.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 6f08c0c3238d..0727383f4940 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -533,7 +533,7 @@ static int tegra_i2c_poll_register(struct tegra_i2c_dev *i2c_dev,
 	void __iomem *addr = i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg);
 	u32 val;
 
-	if (!i2c_dev->atomic_mode)
+	if (!i2c_dev->atomic_mode && !in_irq())
 		return readl_relaxed_poll_timeout(addr, val, !(val & mask),
 						  delay_us, timeout_us);
 
-- 
2.26.2