mfd / platform: cros_ec: Move device sysfs attributes to its own driver

The entire way how cros debugfs attibutes are created is broken.
cros_ec_sysfs should be its own driver and its attributes should be
associated with the sysfs driver not the mfd driver.

The patch also adds the sysfs documentation.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/platform/chrome/Kconfig

@@ -49,9 +49,6 @@ config CHROMEOS_TBMC
 	  To compile this driver as a module, choose M here: the
 	  module will be called chromeos_tbmc.
 
-config CROS_EC_CTL
-        tristate
-
 config CROS_EC_I2C
 	tristate "ChromeOS Embedded Controller (I2C)"
 	depends on MFD_CROS_EC && I2C
@@ -144,4 +141,15 @@ config CROS_EC_DEBUGFS
 	  To compile this driver as a module, choose M here: the
 	  module will be called cros_ec_debugfs.
 
+config CROS_EC_SYSFS
+	tristate "ChromeOS EC control and information through sysfs"
+	depends on MFD_CROS_EC_CHARDEV && SYSFS
+	default MFD_CROS_EC_CHARDEV
+	help
+	  This option exposes some sysfs attributes to control and get
+	  information from ChromeOS EC.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cros_ec_sysfs.
+
 endif # CHROMEOS_PLATFORMS

drivers/platform/chrome/Makefile

@@ -3,8 +3,6 @@
 obj-$(CONFIG_CHROMEOS_LAPTOP)		+= chromeos_laptop.o
 obj-$(CONFIG_CHROMEOS_PSTORE)		+= chromeos_pstore.o
 obj-$(CONFIG_CHROMEOS_TBMC)		+= chromeos_tbmc.o
-cros_ec_ctl-objs			:= cros_ec_sysfs.o
-obj-$(CONFIG_CROS_EC_CTL)		+= cros_ec_ctl.o
 obj-$(CONFIG_CROS_EC_I2C)		+= cros_ec_i2c.o
 obj-$(CONFIG_CROS_EC_SPI)		+= cros_ec_spi.o
 cros_ec_lpcs-objs			:= cros_ec_lpc.o cros_ec_lpc_reg.o
@@ -15,3 +13,4 @@ obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT)	+= cros_kbd_led_backlight.o
 obj-$(CONFIG_CROS_EC_LIGHTBAR)		+= cros_ec_lightbar.o
 obj-$(CONFIG_CROS_EC_VBC)		+= cros_ec_vbc.o
 obj-$(CONFIG_CROS_EC_DEBUGFS)		+= cros_ec_debugfs.o
+obj-$(CONFIG_CROS_EC_SYSFS)		+= cros_ec_sysfs.o

drivers/platform/chrome/cros_ec_lightbar.c

@@ -594,7 +594,7 @@ static umode_t cros_ec_lightbar_attrs_are_visible(struct kobject *kobj,
 	return 0;
 }
 
-struct attribute_group cros_ec_lightbar_attr_group = {
+static struct attribute_group cros_ec_lightbar_attr_group = {
 	.name = "lightbar",
 	.attrs = __lb_cmds_attrs,
 	.is_visible = cros_ec_lightbar_attrs_are_visible,

drivers/platform/chrome/cros_ec_sysfs.c

@@ -34,6 +34,8 @@
 #include <linux/types.h>
 #include <linux/uaccess.h>
 
+#define DRV_NAME "cros-ec-sysfs"
+
 /* Accessor functions */
 
 static ssize_t reboot_show(struct device *dev,
@@ -353,7 +355,39 @@ struct attribute_group cros_ec_attr_group = {
 	.attrs = __ec_attrs,
 	.is_visible = cros_ec_ctrl_visible,
 };
-EXPORT_SYMBOL(cros_ec_attr_group);
+
+static int cros_ec_sysfs_probe(struct platform_device *pd)
+{
+	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+	struct device *dev = &pd->dev;
+	int ret;
+
+	ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
+	if (ret < 0)
+		dev_err(dev, "failed to create attributes. err=%d\n", ret);
+
+	return ret;
+}
+
+static int cros_ec_sysfs_remove(struct platform_device *pd)
+{
+	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+
+	sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
+
+	return 0;
+}
+
+static struct platform_driver cros_ec_sysfs_driver = {
+	.driver = {
+		.name = DRV_NAME,
+	},
+	.probe = cros_ec_sysfs_probe,
+	.remove = cros_ec_sysfs_remove,
+};
+
+module_platform_driver(cros_ec_sysfs_driver);
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("ChromeOS EC control driver");
+MODULE_ALIAS("platform:" DRV_NAME);