From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 17 Jun 2019 12:37:20 +0000 (+0200)
Subject: 4.9-stable patches
X-Git-Tag: v5.1.11~11
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0ce9218a50fe205f93b650a800181f50f62b1ac5;p=thirdparty%2Fkernel%2Fstable-queue.git

4.9-stable patches

added patches:
	rtc-pcf8523-don-t-return-invalid-date-when-battery-is-low.patch
---

diff --git a/queue-4.9/rtc-pcf8523-don-t-return-invalid-date-when-battery-is-low.patch b/queue-4.9/rtc-pcf8523-don-t-return-invalid-date-when-battery-is-low.patch
new file mode 100644
index 00000000000..d4dbe0db151
--- /dev/null
+++ b/queue-4.9/rtc-pcf8523-don-t-return-invalid-date-when-battery-is-low.patch
@@ -0,0 +1,83 @@
+From ecb4a353d3afd45b9bb30c85d03ee113a0589079 Mon Sep 17 00:00:00 2001
+From: Baruch Siach <baruch@tkos.co.il>
+Date: Wed, 5 Dec 2018 17:00:09 +0200
+Subject: rtc: pcf8523: don't return invalid date when battery is low
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Baruch Siach <baruch@tkos.co.il>
+
+commit ecb4a353d3afd45b9bb30c85d03ee113a0589079 upstream.
+
+The RTC_VL_READ ioctl reports the low battery condition. Still,
+pcf8523_rtc_read_time() happily returns invalid dates in this case.
+Check the battery health on pcf8523_rtc_read_time() to avoid that.
+
+Reported-by: Erik Čuk <erik.cuk@domel.com>
+Signed-off-by: Baruch Siach <baruch@tkos.co.il>
+Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/rtc/rtc-pcf8523.c |   32 ++++++++++++++++++++++++--------
+ 1 file changed, 24 insertions(+), 8 deletions(-)
+
+--- a/drivers/rtc/rtc-pcf8523.c
++++ b/drivers/rtc/rtc-pcf8523.c
+@@ -82,6 +82,18 @@ static int pcf8523_write(struct i2c_clie
+ 	return 0;
+ }
+ 
++static int pcf8523_voltage_low(struct i2c_client *client)
++{
++	u8 value;
++	int err;
++
++	err = pcf8523_read(client, REG_CONTROL3, &value);
++	if (err < 0)
++		return err;
++
++	return !!(value & REG_CONTROL3_BLF);
++}
++
+ static int pcf8523_select_capacitance(struct i2c_client *client, bool high)
+ {
+ 	u8 value;
+@@ -164,6 +176,14 @@ static int pcf8523_rtc_read_time(struct
+ 	struct i2c_msg msgs[2];
+ 	int err;
+ 
++	err = pcf8523_voltage_low(client);
++	if (err < 0) {
++		return err;
++	} else if (err > 0) {
++		dev_err(dev, "low voltage detected, time is unreliable\n");
++		return -EINVAL;
++	}
++
+ 	msgs[0].addr = client->addr;
+ 	msgs[0].flags = 0;
+ 	msgs[0].len = 1;
+@@ -248,17 +268,13 @@ static int pcf8523_rtc_ioctl(struct devi
+ 			     unsigned long arg)
+ {
+ 	struct i2c_client *client = to_i2c_client(dev);
+-	u8 value;
+-	int ret = 0, err;
++	int ret;
+ 
+ 	switch (cmd) {
+ 	case RTC_VL_READ:
+-		err = pcf8523_read(client, REG_CONTROL3, &value);
+-		if (err < 0)
+-			return err;
+-
+-		if (value & REG_CONTROL3_BLF)
+-			ret = 1;
++		ret = pcf8523_voltage_low(client);
++		if (ret < 0)
++			return ret;
+ 
+ 		if (copy_to_user((void __user *)arg, &ret, sizeof(int)))
+ 			return -EFAULT;
diff --git a/queue-4.9/series b/queue-4.9/series
index eb1d67d3454..43e12412dce 100644
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -86,3 +86,4 @@ usb-usb-storage-add-new-id-to-ums-realtek.patch
 usb-serial-pl2303-add-allied-telesis-vt-kit3.patch
 usb-serial-option-add-support-for-simcom-sim7500-sim7600-rndis-mode.patch
 usb-serial-option-add-telit-0x1260-and-0x1261-compositions.patch
+rtc-pcf8523-don-t-return-invalid-date-when-battery-is-low.patch