[PATCH AUTOSEL 4.19 180/191] rtc: isl1208: avoid possible sysfs race

Sasha Levin
2019-11-10T03:06:47Z

From: Alexandre Belloni <alexandre.belloni@bootlin.com>

[ Upstream commit 1b4c794fda583edabe864ac466e9cd43c707be80 ]

Use rtc_add_group to add the common sysfs group to avoid a possible race
condition.

[Denis.Osterland@diehl.com: use to_i2c_client(dev->parent)]
Signed-off-by: Denis Osterland <Denis.Osterland@diehl.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The move of atrim, dtrim usr sysfs properties from i2c device
to rtc device require to access them via dev->parent.
This patch also aligns timestamp0.

Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/rtc/rtc-isl1208.c | 27 ++++++++++-----------------
1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/drivers/rtc/rtc-isl1208.c b/drivers/rtc/rtc-isl1208.c
index ea18a8f4bce06..033f65aef5788 100644
--- a/drivers/rtc/rtc-isl1208.c
+++ b/drivers/rtc/rtc-isl1208.c
@@ -518,7 +518,7 @@ static ssize_t timestamp0_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
- struct i2c_client *client = dev_get_drvdata(dev);
+ struct i2c_client *client = to_i2c_client(dev->parent);
int sr;

sr = isl1208_i2c_get_sr(client);
@@ -540,7 +540,7 @@ static ssize_t timestamp0_store(struct device *dev,
static ssize_t timestamp0_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct i2c_client *client = dev_get_drvdata(dev);
+ struct i2c_client *client = to_i2c_client(dev->parent);
u8 regs[ISL1219_EVT_SECTION_LEN] = { 0, };
struct rtc_time tm;
int sr;
@@ -650,7 +650,7 @@ static ssize_t
isl1208_sysfs_show_atrim(struct device *dev,
struct device_attribute *attr, char *buf)
{
- int atr = isl1208_i2c_get_atr(to_i2c_client(dev));
+ int atr = isl1208_i2c_get_atr(to_i2c_client(dev->parent));
if (atr < 0)
return atr;

@@ -663,7 +663,7 @@ static ssize_t
isl1208_sysfs_show_dtrim(struct device *dev,
struct device_attribute *attr, char *buf)
{
- int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev));
+ int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev->parent));
if (dtr < 0)
return dtr;

@@ -676,7 +676,7 @@ static ssize_t
isl1208_sysfs_show_usr(struct device *dev,
struct device_attribute *attr, char *buf)
{
- int usr = isl1208_i2c_get_usr(to_i2c_client(dev));
+ int usr = isl1208_i2c_get_usr(to_i2c_client(dev->parent));
if (usr < 0)
return usr;

@@ -701,7 +701,10 @@ isl1208_sysfs_store_usr(struct device *dev,
if (usr < 0 || usr > 0xffff)
return -EINVAL;

- return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : count;
+ if (isl1208_i2c_set_usr(to_i2c_client(dev->parent), usr))
+ return -EIO;
+
+ return count;
}

static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr,
@@ -765,7 +768,6 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
rtc->ops = &isl1208_rtc_ops;

i2c_set_clientdata(client, rtc);
- dev_set_drvdata(&rtc->dev, client);

rc = isl1208_i2c_get_sr(client);
if (rc < 0) {
@@ -804,7 +806,7 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
evdet_irq = of_irq_get_byname(np, "evdet");
}

- rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
+ rc = rtc_add_group(rtc, &isl1208_rtc_sysfs_files);
if (rc)
return rc;

@@ -821,14 +823,6 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
return rtc_register_device(rtc);
}

-static int
-isl1208_remove(struct i2c_client *client)
-{
- sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
-
- return 0;
-}
-
static const struct i2c_device_id isl1208_id[] = {
{ "isl1208", TYPE_ISL1208 },
{ "isl1218", TYPE_ISL1218 },
@@ -851,7 +845,6 @@ static struct i2c_driver isl1208_driver = {
.of_match_table = of_match_ptr(isl1208_of_match),
},
.probe = isl1208_probe,
- .remove = isl1208_remove,
.id_table = isl1208_id,
};

--
2.20.1