[PATCH v4 1/4] PCI: pciehp: Add pciehp_set_indicators() to jointly set LED indicators

From: Denis Efremov
Date: Tue Sep 03 2019 - 07:10:36 EST


Add pciehp_set_indicators() to set power and attention indicators with a
single register write. Thus, avoiding waiting twice for Command Complete.

Signed-off-by: Denis Efremov <efremov@xxxxxxxxx>
---
drivers/pci/hotplug/pciehp.h | 5 +++++
drivers/pci/hotplug/pciehp_hpc.c | 21 +++++++++++++++++++++
2 files changed, 26 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 8c51a04b8083..0214e09e91a4 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -167,6 +167,11 @@ int pciehp_power_on_slot(struct controller *ctrl);
void pciehp_power_off_slot(struct controller *ctrl);
void pciehp_get_power_status(struct controller *ctrl, u8 *status);

+/* Special values for leaving indicators unchanged */
+#define PCI_EXP_SLTCTL_ATTN_IND_NONE -1 /* Attention Indicator noop */
+#define PCI_EXP_SLTCTL_PWR_IND_NONE -1 /* Power Indicator noop */
+void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);
+
void pciehp_set_attention_status(struct controller *ctrl, u8 status);
void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
int pciehp_query_power_fault(struct controller *ctrl);
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index bd990e3371e3..4d0fe39ef049 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -443,6 +443,27 @@ void pciehp_set_attention_status(struct controller *ctrl, u8 value)
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
}

+void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn)
+{
+ u16 cmd = 0, mask = 0;
+
+ if (PWR_LED(ctrl) && pwr > 0) {
+ cmd |= pwr;
+ mask |= PCI_EXP_SLTCTL_PIC;
+ }
+
+ if (ATTN_LED(ctrl) && attn > 0) {
+ cmd |= attn;
+ mask |= PCI_EXP_SLTCTL_AIC;
+ }
+
+ if (cmd) {
+ pcie_write_cmd_nowait(ctrl, cmd, mask);
+ ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
+ pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
+ }
+}
+
void pciehp_green_led_on(struct controller *ctrl)
{
if (!PWR_LED(ctrl))
--
2.21.0