From: Baruch Siach <baruch@tkos.co.il>
Date: Mon, 5 Aug 2019 06:03:30 +0000 (+0300)
Subject: misc: i2c_eeprom: verify that the chip is functional at probe()
X-Git-Tag: v2019.10-rc4~33^2
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=5ae84860b0428b37063a6d7b03cae26a4e772da7;p=oweals%2Fu-boot.git

misc: i2c_eeprom: verify that the chip is functional at probe()

Read a single byte from EEPROM to verify that it is actually there.

This is equivalent to Linux kernel commit 00f0ea70d2b8 ("eeprom: at24:
check if the chip is functional in probe()").

Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>

hs: fixed style check prefer kernel type 'u8' over 'uint8_t'
---

diff --git a/drivers/misc/i2c_eeprom.c b/drivers/misc/i2c_eeprom.c
index f25d054007..8f2349ad5a 100644
--- a/drivers/misc/i2c_eeprom.c
+++ b/drivers/misc/i2c_eeprom.c
@@ -84,6 +84,14 @@ static int i2c_eeprom_std_ofdata_to_platdata(struct udevice *dev)
 
 static int i2c_eeprom_std_probe(struct udevice *dev)
 {
+	u8 test_byte;
+	int ret;
+
+	/* Verify that the chip is functional */
+	ret = i2c_eeprom_read(dev, 0, &test_byte, 1);
+	if (ret)
+		return -ENODEV;
+
 	return 0;
 }