[PATCH v3 1/4] PCI: pciehp: Add pciehp_set_indicators() to jointly set LED indicators

[Denis Efremov]

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     |  1 +
 drivers/pci/hotplug/pciehp_hpc.c | 29 +++++++++++++++++++++++++++++
 include/uapi/linux/pci_regs.h    |  2 ++
 3 files changed, 32 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 8c51a04b8083..0e272bf3deb4 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -167,6 +167,7 @@ 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);
 
+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..5474b9854a7f 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -443,6 +443,35 @@ 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))
+		switch (pwr) {
+		case PCI_EXP_SLTCTL_PWR_IND_ON:
+		case PCI_EXP_SLTCTL_PWR_IND_BLINK:
+		case PCI_EXP_SLTCTL_PWR_IND_OFF:
+			cmd |= pwr;
+			mask |= PCI_EXP_SLTCTL_PIC;
+		}
+
+	if (ATTN_LED(ctrl))
+		switch (attn) {
+		case PCI_EXP_SLTCTL_ATTN_IND_ON:
+		case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
+		case PCI_EXP_SLTCTL_ATTN_IND_OFF:
+			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))
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index f28e562d7ca8..291788b58f3a 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -591,10 +591,12 @@
 #define  PCI_EXP_SLTCTL_CCIE	0x0010	/* Command Completed Interrupt Enable */
 #define  PCI_EXP_SLTCTL_HPIE	0x0020	/* Hot-Plug Interrupt Enable */
 #define  PCI_EXP_SLTCTL_AIC	0x00c0	/* Attention Indicator Control */
+#define  PCI_EXP_SLTCTL_ATTN_IND_NONE  0x0    /* Attention Indicator noop */
 #define  PCI_EXP_SLTCTL_ATTN_IND_ON    0x0040 /* Attention Indicator on */
 #define  PCI_EXP_SLTCTL_ATTN_IND_BLINK 0x0080 /* Attention Indicator blinking */
 #define  PCI_EXP_SLTCTL_ATTN_IND_OFF   0x00c0 /* Attention Indicator off */
 #define  PCI_EXP_SLTCTL_PIC	0x0300	/* Power Indicator Control */
+#define  PCI_EXP_SLTCTL_PWR_IND_NONE   0x0    /* Power Indicator noop */
 #define  PCI_EXP_SLTCTL_PWR_IND_ON     0x0100 /* Power Indicator on */
 #define  PCI_EXP_SLTCTL_PWR_IND_BLINK  0x0200 /* Power Indicator blinking */
 #define  PCI_EXP_SLTCTL_PWR_IND_OFF    0x0300 /* Power Indicator off */
-- 
2.21.0