[PATCH v6 3/5] PCI: qcom-ep: Add wake up host op to dw_pcie_ep_ops

[Krishna chaitanya chundru <quic_krichai@quicinc.com>]

Add wakeup host op to dw_pcie_ep_ops to wake up host.
If the wakeup type is PME, then trigger inband PME by writing to the PARF
PARF_PM_CTRL register, otherwise toggle #WAKE.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
 drivers/pci/controller/dwc/pcie-qcom-ep.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 627a33a1c5ca..d17e8542d07a 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -97,6 +97,7 @@
 /* PARF_PM_CTRL register fields */
 #define PARF_PM_CTRL_REQ_EXIT_L1		BIT(1)
 #define PARF_PM_CTRL_READY_ENTR_L23		BIT(2)
+#define PARF_PM_CTRL_XMT_PME			BIT(4)
 #define PARF_PM_CTRL_REQ_NOT_ENTR_L1		BIT(5)
 
 /* PARF_MHI_CLOCK_RESET_CTRL fields */
@@ -817,10 +818,34 @@ static void qcom_pcie_ep_init(struct dw_pcie_ep *ep)
 		dw_pcie_ep_reset_bar(pci, bar);
 }
 
+static bool qcom_pcie_ep_wakeup_host(struct dw_pcie_ep *ep, u8 func_no, bool send_pme)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+	struct device *dev = pci->dev;
+	u32 val;
+
+	if (send_pme) {
+		dev_dbg(dev, "Waking up the host using PME\n");
+		val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
+		writel_relaxed(val | PARF_PM_CTRL_XMT_PME, pcie_ep->parf + PARF_PM_CTRL);
+		writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
+
+	} else {
+		dev_dbg(dev, "Waking up the host by toggling WAKE#\n");
+		gpiod_set_value_cansleep(pcie_ep->wake, 1);
+		usleep_range(WAKE_DELAY_US, WAKE_DELAY_US + 500);
+		gpiod_set_value_cansleep(pcie_ep->wake, 0);
+	}
+
+	return true;
+}
+
 static const struct dw_pcie_ep_ops pci_ep_ops = {
 	.init = qcom_pcie_ep_init,
 	.raise_irq = qcom_pcie_ep_raise_irq,
 	.get_features = qcom_pcie_epc_get_features,
+	.wakeup_host = qcom_pcie_ep_wakeup_host,
 };
 
 static int qcom_pcie_ep_probe(struct platform_device *pdev)

-- 
2.42.0