Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "Some bugfixes from I2C:

   - fix a uevent triggered boot problem by removing a useless debug
     print

   - fix sysfs-attributes of the new i2c-demux-pinctrl driver to follow
     standard kernel behaviour

   - fix a potential division-by-zero error (needed two takes)"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: jz4780: really prevent potential division by zero
  Revert "i2c: jz4780: prevent potential division by zero"
  i2c: jz4780: prevent potential division by zero
  i2c: mux: demux-pinctrl: Update docs to new sysfs-attributes
  i2c: mux: demux-pinctrl: Clean up sysfs attributes
  i2c: prevent endless uevent loop with CONFIG_I2C_DEBUG_CORE

4 files changed, 49 insertions, 36 deletions

diff --git a/Documentation/ABI/testing/sysfs-platform-i2c-demux-pinctrl b/Documentation/ABI/testing/sysfs-platform-i2c-demux-pinctrl
index 7ac7d7262bb7..3c3514815cd5 100644
--- a/Documentation/ABI/testing/sysfs-platform-i2c-demux-pinctrl
+++ b/Documentation/ABI/testing/sysfs-platform-i2c-demux-pinctrl
@@ -1,23 +1,18 @@
-What:           /sys/devices/platform/<i2c-demux-name>/cur_master
+What:           /sys/devices/platform/<i2c-demux-name>/available_masters
 Date:           January 2016
 KernelVersion:  4.6
 Contact:        Wolfram Sang <wsa@the-dreams.de>
 Description:
+                Reading the file will give you a list of masters which can be
+                selected for a demultiplexed bus. The format is
+                "<index>:<name>". Example from a Renesas Lager board:
 
-This file selects the active I2C master for a demultiplexed bus.
+                0:/i2c@e6500000 1:/i2c@e6508000
 
-Write 0 there for the first master, 1 for the second etc. Reading the file will
-give you a list with the active master marked. Example from a Renesas Lager
-board:
-
-root@Lager:~# cat /sys/devices/platform/i2c@8/cur_master
-* 0 - /i2c@9
-  1 - /i2c@e6520000
-  2 - /i2c@e6530000
-
-root@Lager:~# echo 2 > /sys/devices/platform/i2c@8/cur_master
-
-root@Lager:~# cat /sys/devices/platform/i2c@8/cur_master
-  0 - /i2c@9
-  1 - /i2c@e6520000
-* 2 - /i2c@e6530000
+What:           /sys/devices/platform/<i2c-demux-name>/current_master
+Date:           January 2016
+KernelVersion:  4.6
+Contact:        Wolfram Sang <wsa@the-dreams.de>
+Description:
+                This file selects/shows the active I2C master for a demultiplexed
+                bus. It uses the <index> value from the file 'available_masters'.
diff --git a/drivers/i2c/busses/i2c-jz4780.c b/drivers/i2c/busses/i2c-jz4780.c
index f325663c27c5..ba14a863b451 100644
--- a/drivers/i2c/busses/i2c-jz4780.c
+++ b/drivers/i2c/busses/i2c-jz4780.c
@@ -771,11 +771,16 @@ static int jz4780_i2c_probe(struct platform_device *pdev)
         ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
                                    &clk_freq);
         if (ret) {
-                dev_err(&pdev->dev, "clock-frequency not specified in DT");
+                dev_err(&pdev->dev, "clock-frequency not specified in DT\n");
                 goto err;
         }
 
         i2c->speed = clk_freq / 1000;
+        if (i2c->speed == 0) {
+                ret = -EINVAL;
+                dev_err(&pdev->dev, "clock-frequency minimum is 1000\n");
+                goto err;
+        }
         jz4780_i2c_set_speed(i2c);
 
         dev_info(&pdev->dev, "Bus frequency is %d KHz\n", i2c->speed);
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 0f2f8484e8ec..e584d88ee337 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -525,22 +525,16 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
         return 0;
 }
 
-
-/* uevent helps with hotplug: modprobe -q $(MODALIAS) */
 static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
-        struct i2c_client       *client = to_i2c_client(dev);
+        struct i2c_client *client = to_i2c_client(dev);
         int rc;
 
         rc = acpi_device_uevent_modalias(dev, env);
         if (rc != -ENODEV)
                 return rc;
 
-        if (add_uevent_var(env, "MODALIAS=%s%s",
-                           I2C_MODULE_PREFIX, client->name))
-                return -ENOMEM;
-        dev_dbg(dev, "uevent\n");
-        return 0;
+        return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name);
 }
 
 /* i2c bus recovery routines */
diff --git a/drivers/i2c/muxes/i2c-demux-pinctrl.c b/drivers/i2c/muxes/i2c-demux-pinctrl.c
index 7748a0a5ddb9..8de073aed001 100644
--- a/drivers/i2c/muxes/i2c-demux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-demux-pinctrl.c
@@ -140,22 +140,34 @@ static int i2c_demux_change_master(struct i2c_demux_pinctrl_priv *priv, u32 new_
         return i2c_demux_activate_master(priv, new_chan);
 }
 
-static ssize_t cur_master_show(struct device *dev, struct device_attribute *attr,
-                           char *buf)
+static ssize_t available_masters_show(struct device *dev,
+                                      struct device_attribute *attr,
+                                      char *buf)
 {
         struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev);
         int count = 0, i;
 
         for (i = 0; i < priv->num_chan && count < PAGE_SIZE; i++)
-                count += scnprintf(buf + count, PAGE_SIZE - count, "%c %d - %s\n",
-                                 i == priv->cur_chan ? '*' : ' ', i,
-                                 priv->chan[i].parent_np->full_name);
+                count += scnprintf(buf + count, PAGE_SIZE - count, "%d:%s%c",
+                                   i, priv->chan[i].parent_np->full_name,
+                                   i == priv->num_chan - 1 ? '\n' : ' ');
 
         return count;
 }
+static DEVICE_ATTR_RO(available_masters);
 
-static ssize_t cur_master_store(struct device *dev, struct device_attribute *attr,
-                            const char *buf, size_t count)
+static ssize_t current_master_show(struct device *dev,
+                                   struct device_attribute *attr,
+                                   char *buf)
+{
+        struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev);
+
+        return sprintf(buf, "%d\n", priv->cur_chan);
+}
+
+static ssize_t current_master_store(struct device *dev,
+                                    struct device_attribute *attr,
+                                    const char *buf, size_t count)
 {
         struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev);
         unsigned int val;
@@ -172,7 +184,7 @@ static ssize_t cur_master_store(struct device *dev, struct device_attribute *att
 
         return ret < 0 ? ret : count;
 }
-static DEVICE_ATTR_RW(cur_master);
+static DEVICE_ATTR_RW(current_master);
 
 static int i2c_demux_pinctrl_probe(struct platform_device *pdev)
 {
@@ -218,12 +230,18 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev)
         /* switch to first parent as active master */
         i2c_demux_activate_master(priv, 0);
 
-        err = device_create_file(&pdev->dev, &dev_attr_cur_master);
+        err = device_create_file(&pdev->dev, &dev_attr_available_masters);
         if (err)
                 goto err_rollback;
 
+        err = device_create_file(&pdev->dev, &dev_attr_current_master);
+        if (err)
+                goto err_rollback_available;
+
         return 0;
 
+err_rollback_available:
+        device_remove_file(&pdev->dev, &dev_attr_available_masters);
 err_rollback:
         for (j = 0; j < i; j++) {
                 of_node_put(priv->chan[j].parent_np);
@@ -238,7 +256,8 @@ static int i2c_demux_pinctrl_remove(struct platform_device *pdev)
         struct i2c_demux_pinctrl_priv *priv = platform_get_drvdata(pdev);
         int i;
 
-        device_remove_file(&pdev->dev, &dev_attr_cur_master);
+        device_remove_file(&pdev->dev, &dev_attr_current_master);
+        device_remove_file(&pdev->dev, &dev_attr_available_masters);
 
         i2c_demux_deactivate_master(priv);