Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754032AbdFSKAS (ORCPT ); Mon, 19 Jun 2017 06:00:18 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:10159 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1753789AbdFSKAO (ORCPT ); Mon, 19 Jun 2017 06:00:14 -0400 From: Ryder Lee To: Bjorn Helgaas CC: , , , , Ryder Lee Subject: [PATCH 2/3] PCI: mediatek: turn off subsys power if no link up detected Date: Mon, 19 Jun 2017 17:59:59 +0800 Message-ID: <1497866400-41844-3-git-send-email-ryder.lee@mediatek.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1497866400-41844-1-git-send-email-ryder.lee@mediatek.com> References: <1497866400-41844-1-git-send-email-ryder.lee@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2857 Lines: 104 There is no need to keep controller power on if slots are all empty, so a check is added to turn it off. Besides, host controllers may not need PM domain in some SoCs, thus we add dev->pm_domain to check that. Signed-off-by: Ryder Lee --- drivers/pci/host/pcie-mediatek.c | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c index 165d82d..d256263 100644 --- a/drivers/pci/host/pcie-mediatek.c +++ b/drivers/pci/host/pcie-mediatek.c @@ -118,6 +118,18 @@ static inline bool mtk_pcie_link_is_up(struct mtk_pcie_port *port) return !!(readl(port->base + PCIE_LINK_STATUS) & PCIE_PORT_LINKUP); } +static void mtk_pcie_subsys_powerdown(struct mtk_pcie *pcie) +{ + struct device *dev = pcie->dev; + + clk_disable_unprepare(pcie->free_ck); + + if (dev->pm_domain) { + pm_runtime_put_sync(dev); + pm_runtime_disable(dev); + } +} + static void mtk_pcie_port_free(struct mtk_pcie_port *port) { struct mtk_pcie *pcie = port->pcie; @@ -130,7 +142,6 @@ static void mtk_pcie_port_free(struct mtk_pcie_port *port) static void mtk_pcie_put_resources(struct mtk_pcie *pcie) { - struct device *dev = pcie->dev; struct mtk_pcie_port *port, *tmp; list_for_each_entry_safe(port, tmp, &pcie->ports, list) { @@ -139,9 +150,7 @@ static void mtk_pcie_put_resources(struct mtk_pcie *pcie) mtk_pcie_port_free(port); } - clk_disable_unprepare(pcie->free_ck); - pm_runtime_put_sync(dev); - pm_runtime_disable(dev); + mtk_pcie_subsys_powerdown(pcie); } static void __iomem *mtk_pcie_map_bus(struct pci_bus *bus, @@ -340,10 +349,10 @@ static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie) return PTR_ERR(pcie->free_ck); } - pm_runtime_enable(dev); - err = pm_runtime_get_sync(dev); - if (err) - goto err_pm; + if (dev->pm_domain) { + pm_runtime_enable(dev); + pm_runtime_get_sync(dev); + } /* enable top level clock */ err = clk_prepare_enable(pcie->free_ck); @@ -355,9 +364,10 @@ static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie) return 0; err_free_ck: - pm_runtime_put_sync(dev); -err_pm: - pm_runtime_disable(dev); + if (dev->pm_domain) { + pm_runtime_put_sync(dev); + pm_runtime_disable(dev); + } return err; } @@ -439,6 +449,10 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie) list_for_each_entry_safe(port, tmp, &pcie->ports, list) mtk_pcie_enable_ports(port); + /* power down PCIe subsys if slots are all empty(link down) */ + if (list_empty(&pcie->ports)) + mtk_pcie_subsys_powerdown(pcie); + return 0; } @@ -522,7 +536,9 @@ static int mtk_pcie_probe(struct platform_device *pdev) return 0; put_resources: - mtk_pcie_put_resources(pcie); + if (!list_empty(&pcie->ports)) + mtk_pcie_put_resources(pcie); + return err; } -- 1.9.1