From 73d88cf9719e505eedb389d117704f806e4747d1 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Pawe=C5=82=20Anikiel?= <pan@semihalf.com>
Date: Fri, 17 Jun 2022 12:47:21 +0200
Subject: [PATCH] misc: atsha204a: Increase wake delay by tWHI
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From the ATSHA204A datasheet (document DS40002025A):
Wake: If SDA is held low for a period greater than tWLO, the device
exits low-power mode and, after a delay of tWHI, is ready to receive
I2C commands.
tWHI value can be found in table 7-2.
Signed-off-by: PaweÅ Anikiel <pan@semihalf.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
drivers/misc/atsha204a-i2c.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/misc/atsha204a-i2c.c b/drivers/misc/atsha204a-i2c.c
index aa6acf0f9a..81ecb5b617 100644
--- a/drivers/misc/atsha204a-i2c.c
+++ b/drivers/misc/atsha204a-i2c.c
@@ -21,7 +21,8 @@
#include <linux/bitrev.h>
#include <u-boot/crc.h>
-#define ATSHA204A_TWLO 60
+#define ATSHA204A_TWLO_US 60
+#define ATSHA204A_TWHI_US 2500
#define ATSHA204A_TRANSACTION_TIMEOUT 100000
#define ATSHA204A_TRANSACTION_RETRY 5
#define ATSHA204A_EXECTIME 5000
@@ -109,7 +110,7 @@ int atsha204a_wakeup(struct udevice *dev)
continue;
}
- udelay(ATSHA204A_TWLO);
+ udelay(ATSHA204A_TWLO_US + ATSHA204A_TWHI_US);
res = atsha204a_recv_resp(dev, &resp);
if (res) {
--
2.39.5