From 688033f52d7192ea8ddf617b86af0a4120247b42 Mon Sep 17 00:00:00 2001
From: Denis Efremov <efremov@linux.com>
Date: Tue, 3 Sep 2019 14:10:18 +0300
Subject: [PATCH] PCI: pciehp: Add pciehp_set_indicators() to set both
 indicators

Add pciehp_set_indicators() to set power and attention indicators with a
single register write.

This is a minor optimization because we frequently set both indicators and
this can do it with a single command.  It also reduces the number of
interfaces related to the indicators and makes them more discoverable
because callers use the PCI_EXP_SLTCTL_ATTN_IND_* and
PCI_EXP_SLTCTL_PWR_IND_* definitions directly.

[bhelgaas: extend commit log, s/PCI_EXP_SLTCTL_.*_IND_NONE/INDICATOR_NOOP/
so they don't look like things defined by the spec, add function doc, mask
commands to make it obvious we only send valid commands
(pcie_do_write_cmd() does mask it, but requires more effort to verify)]
Link: https://lore.kernel.org/r/20190903111021.1559-2-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/hotplug/pciehp.h     |  3 +++
 drivers/pci/hotplug/pciehp_hpc.c | 36 ++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 8c51a04b8083e..2ca0f35a6a234 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -167,6 +167,9 @@ 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);
 
+#define INDICATOR_NOOP -1	/* Leave indicator unchanged */
+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 bd990e3371e31..d7ebcd7111cb7 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -443,6 +443,42 @@ void pciehp_set_attention_status(struct controller *ctrl, u8 value)
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 }
 
+/**
+ * pciehp_set_indicators() - set attention indicator, power indicator, or both
+ * @ctrl: PCIe hotplug controller
+ * @pwr: one of:
+ *	PCI_EXP_SLTCTL_PWR_IND_ON
+ *	PCI_EXP_SLTCTL_PWR_IND_BLINK
+ *	PCI_EXP_SLTCTL_PWR_IND_OFF
+ * @attn: one of:
+ *	PCI_EXP_SLTCTL_ATTN_IND_ON
+ *	PCI_EXP_SLTCTL_ATTN_IND_BLINK
+ *	PCI_EXP_SLTCTL_ATTN_IND_OFF
+ *
+ * Either @pwr or @attn can also be INDICATOR_NOOP to leave that indicator
+ * unchanged.
+ */
+void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn)
+{
+	u16 cmd = 0, mask = 0;
+
+	if (PWR_LED(ctrl) && pwr != INDICATOR_NOOP) {
+		cmd |= (pwr & PCI_EXP_SLTCTL_PIC);
+		mask |= PCI_EXP_SLTCTL_PIC;
+	}
+
+	if (ATTN_LED(ctrl) && attn != INDICATOR_NOOP) {
+		cmd |= (attn & PCI_EXP_SLTCTL_AIC);
+		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))
-- 
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