From ca514d0267f92d8aac2eb5f92ff7d150078df423 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Thu, 4 Aug 2022 13:03:44 +0200
Subject: [PATCH] misc: atsha204a: Don't check for error when waking up the
device
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The device ignores any levels or transitions on the SCL pin when the device
is idle, asleep or during waking up.
Linux kernel driver for atsha204a (atmel-sha204a.ko) also ignores return
value from i2c wakeup send command, see:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/crypto/atmel-i2c.c?h=v5.19#n174
And also userspace Turris libatsha204 library ignores return value from
wakeup send command, see:
https://gitlab.nic.cz/turris/libatsha204/-/blob/v29.2/src/libatsha204/layer_ni2c.c#L75-76
U-Boot driver should do same thing.
Fixes waking up ATSHA204 on Turris 1.x boards.
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: PaweÅ Anikiel <pan@semihalf.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
---
drivers/misc/atsha204a-i2c.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/misc/atsha204a-i2c.c b/drivers/misc/atsha204a-i2c.c
index e7c6be593d..d3c515828f 100644
--- a/drivers/misc/atsha204a-i2c.c
+++ b/drivers/misc/atsha204a-i2c.c
@@ -103,12 +103,13 @@ int atsha204a_wakeup(struct udevice *dev)
for (try = 1; try <= 10; ++try) {
debug("Try %i... ", try);
+ /*
+ * The device ignores any levels or transitions on the SCL pin
+ * when the device is idle, asleep or during waking up.
+ * Don't check for error when waking up the device.
+ */
memset(req, 0, 4);
- res = atsha204a_send(dev, req, 4);
- if (res) {
- debug("failed on I2C send, trying again\n");
- continue;
- }
+ atsha204a_send(dev, req, 4);
udelay(ATSHA204A_TWLO_US + ATSHA204A_TWHI_US);
--
2.39.5