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authorLukas Wunner <lukas@wunner.de>2018-09-08 09:59:01 +0200
committerBjorn Helgaas <bhelgaas@google.com>2018-09-18 17:52:15 -0500
commitd758714235e7abb7984468370c912ca2f4dc4e57 (patch)
tree8c49e29d5dd2d6abcdde8f442ea464db74318125
parent4ff3126e80fc2db9d961467f783b5c2f4ccd1ca9 (diff)
PCI: pciehp: Reshuffle controller struct for clarity
The members in pciehp's controller struct are arranged in a seemingly arbitrary order and have grown to an amount that I no longer consider easily graspable by contributors. Sort the members into 5 rubrics: * Slot Capabilities register and quirks * Slot Control register access * Slot Status register event handling * state machine * hotplug core interface Obviously, this is just my personal bikeshed color and if anyone has a better idea, please come forward. Any ordering will do as long as the information is presented in a manageable manner. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
-rw-r--r--drivers/pci/hotplug/pciehp.h57
1 files changed, 31 insertions, 26 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 39b97e2384c3..3cc88f3e4368 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -60,38 +60,38 @@ do { \
/**
* struct controller - PCIe hotplug controller
- * @ctrl_lock: serializes writes to the Slot Control register
* @pcie: pointer to the controller's PCIe port service device
- * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
- * Link Status register and to the Presence Detect State bit in the Slot
- * Status register during a slot reset which may cause them to flap
- * @queue: wait queue to wake up on reception of a Command Completed event,
- * used for synchronous writes to the Slot Control register
* @slot_cap: cached copy of the Slot Capabilities register
+ * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
+ * Capable bit in Link Capabilities register; if this bit is zero, the
+ * Data Link Layer Link Active bit in the Link Status register will never
+ * be set and the driver is thus confined to wait 1 second before assuming
+ * the link to a hotplugged device is up and accessing it
* @slot_ctrl: cached copy of the Slot Control register
- * @poll_thread: thread to poll for slot events if no IRQ is available,
- * enabled with pciehp_poll_mode module parameter
+ * @ctrl_lock: serializes writes to the Slot Control register
* @cmd_started: jiffies when the Slot Control register was last written;
* the next write is allowed 1 second later, absent a Command Completed
* interrupt (PCIe r4.0, sec 6.7.3.2)
* @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
* on reception of a Command Completed event
- * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
- * Capable bit in Link Capabilities register; if this bit is zero, the
- * Data Link Layer Link Active bit in the Link Status register will never
- * be set and the driver is thus confined to wait 1 second before assuming
- * the link to a hotplugged device is up and accessing it
+ * @queue: wait queue to wake up on reception of a Command Completed event,
+ * used for synchronous writes to the Slot Control register
+ * @pending_events: used by the IRQ handler to save events retrieved from the
+ * Slot Status register for later consumption by the IRQ thread
* @notification_enabled: whether the IRQ was requested successfully
* @power_fault_detected: whether a power fault was detected by the hardware
* that has not yet been cleared by the user
- * @pending_events: used by the IRQ handler to save events retrieved from the
- * Slot Status register for later consumption by the IRQ thread
+ * @poll_thread: thread to poll for slot events if no IRQ is available,
+ * enabled with pciehp_poll_mode module parameter
* @state: current state machine position
* @state_lock: protects reads and writes of @state;
* protects scheduling, execution and cancellation of @button_work
* @button_work: work item to turn the slot on or off after 5 seconds
* in response to an Attention Button press
* @hotplug_slot: pointer to the structure registered with the PCI hotplug core
+ * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
+ * Link Status register and to the Presence Detect State bit in the Slot
+ * Status register during a slot reset which may cause them to flap
* @request_result: result of last user request submitted to the IRQ thread
* @requester: wait queue to wake up on completion of user request,
* used for synchronous slot enable/disable request via sysfs
@@ -100,23 +100,28 @@ do { \
* unlike other drivers, the two aren't represented by separate structures.
*/
struct controller {
- struct mutex ctrl_lock;
struct pcie_device *pcie;
- struct rw_semaphore reset_lock;
- wait_queue_head_t queue;
- u32 slot_cap;
- u16 slot_ctrl;
- struct task_struct *poll_thread;
- unsigned long cmd_started; /* jiffies */
- unsigned int cmd_busy:1;
+
+ u32 slot_cap; /* capabilities and quirks */
unsigned int link_active_reporting:1;
+
+ u16 slot_ctrl; /* control register access */
+ struct mutex ctrl_lock;
+ unsigned long cmd_started;
+ unsigned int cmd_busy:1;
+ wait_queue_head_t queue;
+
+ atomic_t pending_events; /* event handling */
unsigned int notification_enabled:1;
unsigned int power_fault_detected;
- atomic_t pending_events;
- u8 state;
+ struct task_struct *poll_thread;
+
+ u8 state; /* state machine */
struct mutex state_lock;
struct delayed_work button_work;
- struct hotplug_slot *hotplug_slot;
+
+ struct hotplug_slot *hotplug_slot; /* hotplug core interface */
+ struct rw_semaphore reset_lock;
int request_result;
wait_queue_head_t requester;
};