[PATCH v4 4/6] PCI: dwc: Add dw_pcie_host_ops.host_exit() callback

From: Richard Zhu
Date: Mon Nov 01 2021 - 02:44:14 EST


When link is never came up in the link training after host_init.
The clocks and power supplies usage counter balance should be handled
properly on some DWC platforms (for example, i.MX PCIe).

Add a new host_exit() callback into dw_pcie_host_ops, then it could be
invoked to handle the unbalance issue in the error handling after
host_init() function when link is down.

Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 5 ++++-
drivers/pci/controller/dwc/pcie-designware.h | 1 +
2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index f4755f3a03be..461863bde3c9 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -405,7 +405,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
if (!dw_pcie_link_up(pci) && pci->ops && pci->ops->start_link) {
ret = pci->ops->start_link(pci);
if (ret)
- goto err_free_msi;
+ goto err_host_init;
}

/* Ignore errors, the link may come up later */
@@ -417,6 +417,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
if (!ret)
return 0;

+err_host_init:
+ if (pp->ops->host_exit)
+ pp->ops->host_exit(pp);
err_free_msi:
if (pp->has_msi_ctrl)
dw_pcie_free_msi(pp);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 7d6e9b7576be..1153687ea9a6 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -174,6 +174,7 @@ enum dw_pcie_device_mode {

struct dw_pcie_host_ops {
int (*host_init)(struct pcie_port *pp);
+ void (*host_exit)(struct pcie_port *pp);
int (*msi_host_init)(struct pcie_port *pp);
};

--
2.25.1