From: Jiang Liu <[email protected]>

This patch implements ACPI hotplug sysfs interfaces for system device hotplug.

enable: (It should be named 'power', but that causes name conflicts.)
echo 1 > enable: power on the hotplug slot.
echo 0 > enable: power off the hotplug slot.

connect:
echo 1 > connect: create ACPI devices for system devices connecting to a slot
echo 0 > connect: remove ACPI devices for system devices connecting to a slot

configure:
echo 1 > configure: add system devices into running system
echo 0 > configure: remove system devices from running system

dependency:
cat dependency: show slots have dependency on this slot if the slot is powered,
                otherwise show slots this slot depends on.

Signed-off-by: Jiang Liu <[email protected]>
---
 drivers/acpi/hotplug/Makefile     |    1 +
 drivers/acpi/hotplug/acpihp_drv.h |    3 +
 drivers/acpi/hotplug/drv_main.c   |    6 +
 drivers/acpi/hotplug/sysfs.c      |  246 +++++++++++++++++++++++++++++++++++++
 4 files changed, 256 insertions(+)
 create mode 100644 drivers/acpi/hotplug/sysfs.c

diff --git a/drivers/acpi/hotplug/Makefile b/drivers/acpi/hotplug/Makefile
index 9383320..88c7595 100644
--- a/drivers/acpi/hotplug/Makefile
+++ b/drivers/acpi/hotplug/Makefile
@@ -15,3 +15,4 @@ acpihp_drv-y                                  += dependency.o
 acpihp_drv-y                                   += cancel.o
 acpihp_drv-y                                   += configure.o
 acpihp_drv-y                                   += state_machine.o
+acpihp_drv-y                                   += sysfs.o
diff --git a/drivers/acpi/hotplug/acpihp_drv.h 
b/drivers/acpi/hotplug/acpihp_drv.h
index 3b6dbdd..d339f9a 100644
--- a/drivers/acpi/hotplug/acpihp_drv.h
+++ b/drivers/acpi/hotplug/acpihp_drv.h
@@ -101,4 +101,7 @@ int acpihp_drv_unconfigure(struct list_head *list);
 /* The heart of the ACPI system device hotplug driver */
 int acpihp_drv_change_state(struct acpihp_slot *slot, enum acpihp_drv_cmd cmd);
 
+int acpihp_drv_create_sysfs(struct acpihp_slot *slot);
+void acpihp_drv_remove_sysfs(struct acpihp_slot *slot);
+
 #endif /* __ACPIHP_DRV_H__ */
diff --git a/drivers/acpi/hotplug/drv_main.c b/drivers/acpi/hotplug/drv_main.c
index 538772d..9858fdd 100644
--- a/drivers/acpi/hotplug/drv_main.c
+++ b/drivers/acpi/hotplug/drv_main.c
@@ -280,6 +280,11 @@ static int acpihp_drv_slot_add(struct device *dev, struct 
class_interface *intf)
                return -ENOMEM;
        }
 
+       if (acpihp_drv_create_sysfs(slot))
+               ACPIHP_DEBUG("fails to create sysfs interfaces for slot %s, "
+                            "some function will not be available to user.\n",
+                            slot->name);
+
        ACPIHP_INFO("found hotplug slot %s.\n", slot->full_path);
 
        return 0;
@@ -294,6 +299,7 @@ static void acpihp_drv_intf_remove(struct device *dev,
 
        ACPIHP_INFO("remove hotplug slot %s.\n", slot->full_path);
 
+       acpihp_drv_remove_sysfs(slot);
        acpihp_drv_uninstall_handler(slot);
        acpihp_drv_remove_devices(slot);
        acpihp_slot_detach_drv_data(slot, intf, (void **)&drv_data);
diff --git a/drivers/acpi/hotplug/sysfs.c b/drivers/acpi/hotplug/sysfs.c
new file mode 100644
index 0000000..62c1892
--- /dev/null
+++ b/drivers/acpi/hotplug/sysfs.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2011 Huawei Tech. Co., Ltd.
+ * Copyright (C) 2011 Jiang Liu <[email protected]>
+ * Copyright (C) 2011 Hanjun Guo <[email protected]>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <acpi/acpi_hotplug.h>
+#include "acpihp_drv.h"
+
+static ssize_t acpihp_drv_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count,
+               enum acpihp_drv_cmd op_set, enum acpihp_drv_cmd op_clr)
+{
+       unsigned long val;
+       ssize_t result = kstrtoul(buf, 0, &val);
+       struct acpihp_slot *slot = container_of(dev, struct acpihp_slot, dev);
+
+       if (result < 0)
+               return result;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       if (val)
+               result = acpihp_drv_change_state(slot, op_set);
+       else
+               result = acpihp_drv_change_state(slot, op_clr);
+
+       return result < 0 ? result : count;
+}
+
+static inline ssize_t acpihp_drv_print_bool(char *page, bool flag)
+{
+       return snprintf(page, PAGE_SIZE, flag ? "1\n" : "0\n");
+}
+
+static ssize_t acpihp_drv_power_show(struct device *dev,
+               struct device_attribute *attr, char *page)
+{
+       bool flag;
+       struct acpihp_slot *slot = container_of(dev, struct acpihp_slot, dev);
+
+       acpihp_drv_update_slot_state(slot);
+       mutex_lock(&slot->slot_mutex);
+       switch (slot->state) {
+       case ACPIHP_SLOT_STATE_POWERED:
+       case ACPIHP_SLOT_STATE_CONNECTED:
+       case ACPIHP_SLOT_STATE_CONFIGURED:
+       case ACPIHP_SLOT_STATE_POWERING_ON:
+       case ACPIHP_SLOT_STATE_POWERING_OFF:
+       case ACPIHP_SLOT_STATE_CONNECTING:
+       case ACPIHP_SLOT_STATE_DISCONNECTING:
+       case ACPIHP_SLOT_STATE_CONFIGURING:
+       case ACPIHP_SLOT_STATE_UNCONFIGURING:
+               flag = true;
+               break;
+       default:
+               flag = false;
+               break;
+       }
+       mutex_unlock(&slot->slot_mutex);
+
+       return acpihp_drv_print_bool(page, flag);
+}
+
+static ssize_t acpihp_drv_power_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count)
+{
+       return acpihp_drv_store(dev, attr, buf, count,
+                       ACPIHP_DRV_CMD_POWERON, ACPIHP_DRV_CMD_POWEROFF);
+}
+
+/* It should be named as 'power', but that will cause name conflics. */
+DEVICE_ATTR(enable, S_IRUSR | S_IWUSR,
+           &acpihp_drv_power_show, &acpihp_drv_power_store);
+
+static ssize_t acpihp_drv_connect_show(struct device *dev,
+               struct device_attribute *attr, char *page)
+{
+       bool flag;
+       struct acpihp_slot *slot = container_of(dev, struct acpihp_slot, dev);
+
+       acpihp_drv_update_slot_state(slot);
+       mutex_lock(&slot->slot_mutex);
+       switch (slot->state) {
+       case ACPIHP_SLOT_STATE_CONNECTED:
+       case ACPIHP_SLOT_STATE_CONFIGURED:
+       case ACPIHP_SLOT_STATE_CONNECTING:
+       case ACPIHP_SLOT_STATE_DISCONNECTING:
+       case ACPIHP_SLOT_STATE_CONFIGURING:
+       case ACPIHP_SLOT_STATE_UNCONFIGURING:
+               flag = true;
+               break;
+       default:
+               flag = false;
+               break;
+       }
+       mutex_unlock(&slot->slot_mutex);
+
+       return acpihp_drv_print_bool(page, flag);
+}
+
+static ssize_t acpihp_drv_connect_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count)
+{
+       return acpihp_drv_store(dev, attr, buf, count,
+                       ACPIHP_DRV_CMD_CONNECT, ACPIHP_DRV_CMD_DISCONNECT);
+}
+
+DEVICE_ATTR(connect, S_IRUSR | S_IWUSR,
+           &acpihp_drv_connect_show, &acpihp_drv_connect_store);
+
+static ssize_t acpihp_drv_configure_show(struct device *dev,
+               struct device_attribute *attr, char *page)
+{
+       bool flag;
+       struct acpihp_slot *slot = container_of(dev, struct acpihp_slot, dev);
+
+       acpihp_drv_update_slot_state(slot);
+       mutex_lock(&slot->slot_mutex);
+       switch (slot->state) {
+       case ACPIHP_SLOT_STATE_CONFIGURED:
+       case ACPIHP_SLOT_STATE_CONFIGURING:
+       case ACPIHP_SLOT_STATE_UNCONFIGURING:
+               flag = true;
+               break;
+       default:
+               flag = false;
+               break;
+       }
+       mutex_unlock(&slot->slot_mutex);
+
+       return acpihp_drv_print_bool(page, flag);
+}
+
+static ssize_t acpihp_drv_configure_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count)
+{
+       return acpihp_drv_store(dev, attr, buf, count,
+                       ACPIHP_DRV_CMD_CONFIGURE, ACPIHP_DRV_CMD_UNCONFIGURE);
+}
+
+DEVICE_ATTR(configure, S_IRUSR | S_IWUSR,
+           &acpihp_drv_configure_show, &acpihp_drv_configure_store);
+
+static ssize_t acpihp_drv_dependency_show(struct device *dev,
+               struct device_attribute *attr, char *page)
+{
+       int ret;
+       char *p, *end;
+       struct list_head list;
+       enum acpihp_drv_cmd cmd;
+       struct acpihp_slot_dependency *dep;
+       struct acpihp_slot *slot = container_of(dev, struct acpihp_slot, dev);
+
+       INIT_LIST_HEAD(&list);
+       mutex_lock(&state_machine_mutex);
+       cmd = acpihp_slot_powered(slot) ? ACPIHP_DRV_CMD_POWEROFF :
+                                         ACPIHP_DRV_CMD_POWERON;
+       ret = acpihp_drv_generate_dependency_list(slot, &list, cmd);
+       if (ret) {
+               ret = -ENXIO;
+       } else {
+               p = page;
+               end = page + PAGE_SIZE;
+
+               list_for_each_entry(dep, &list, node) {
+                       if (dep->slot == slot)
+                               continue;
+                       if (p + strlen(dep->slot->full_path) + 2 >= end)
+                               break;
+                       p += snprintf(p, end - p, "%s\n", dep->slot->full_path);
+               }
+
+               acpihp_drv_destroy_dependency_list(&list);
+               ret = p - page;
+       }
+       mutex_unlock(&state_machine_mutex);
+
+       return ret;
+}
+
+static DEVICE_ATTR(dependency, S_IRUSR | S_IWUSR,
+                  &acpihp_drv_dependency_show, NULL);
+
+int acpihp_drv_create_sysfs(struct acpihp_slot *slot)
+{
+       int retval;
+       struct device *dev = &slot->dev;
+
+       retval = device_create_file(dev, &dev_attr_enable);
+       if (retval)
+               goto out;
+       retval = device_create_file(dev, &dev_attr_connect);
+       if (retval)
+               goto out1;
+       retval = device_create_file(dev, &dev_attr_configure);
+       if (retval)
+               goto out2;
+       retval = device_create_file(dev, &dev_attr_dependency);
+       if (retval)
+               goto out3;
+
+       return 0;
+
+out3:
+       device_remove_file(dev, &dev_attr_configure);
+out2:
+       device_remove_file(dev, &dev_attr_connect);
+out1:
+       device_remove_file(dev, &dev_attr_enable);
+out:
+       ACPIHP_DEBUG("fails to create sysfs interfaces for slot %s.\n",
+                    slot->name);
+       return retval;
+}
+
+void acpihp_drv_remove_sysfs(struct acpihp_slot *slot)
+{
+       struct device *dev = &slot->dev;
+
+       device_remove_file(dev, &dev_attr_dependency);
+       device_remove_file(dev, &dev_attr_configure);
+       device_remove_file(dev, &dev_attr_connect);
+       device_remove_file(dev, &dev_attr_enable);
+}
-- 
1.7.9.5


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to