From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Thompson Subject: Re: [project-aspen-dev] [PATCH] PCI: histb: add power control GPIO for PCIe slot Date: Tue, 23 Jan 2018 09:39:44 +0000 Message-ID: <20180123093944.rxysbjm2u6suycco@oak.lan> References: <1516669477-20151-1-git-send-email-shawn.guo@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1516669477-20151-1-git-send-email-shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Shawn Guo Cc: Bjorn Helgaas , Rob Herring , linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, project-aspen-dev-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, Jianguo Sun List-Id: devicetree@vger.kernel.org On Tue, Jan 23, 2018 at 09:04:37AM +0800, Shawn Guo wrote: > From: Jianguo Sun > > Besides the GPIO for controlling reset, there is also possibly another > GPIO for turning on/off the power of PCIe slot. Let's add the support > for that with another optional device tree property 'power-gpios'. > > Signed-off-by: Jianguo Sun > Signed-off-by: Shawn Guo > --- > .../bindings/pci/hisilicon-histb-pcie.txt | 1 + > drivers/pci/dwc/pcie-histb.c | 28 +++++++++++++++++++--- > 2 files changed, 26 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt b/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt > index c84bc027930b..597397a048f8 100644 > --- a/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt > +++ b/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt > @@ -33,6 +33,7 @@ Required properties > "bus": bus reset. > > Optional properties: > +- power-gpios: The gpio to control the power of PCIe slot. > - reset-gpios: The gpio to generate PCIe PERST# assert and deassert signal. > - phys: List of phandle and phy mode specifier, should be 0. > - phy-names: Must be "phy". > diff --git a/drivers/pci/dwc/pcie-histb.c b/drivers/pci/dwc/pcie-histb.c > index 33b01b734d7d..2a6b18619b25 100644 > --- a/drivers/pci/dwc/pcie-histb.c > +++ b/drivers/pci/dwc/pcie-histb.c > @@ -63,6 +63,7 @@ struct histb_pcie { > struct reset_control *sys_reset; > struct reset_control *bus_reset; > void __iomem *ctrl; > + int power_gpio; > int reset_gpio; > }; > > @@ -230,6 +231,8 @@ static void histb_pcie_host_disable(struct histb_pcie *hipcie) > > if (gpio_is_valid(hipcie->reset_gpio)) > gpio_set_value_cansleep(hipcie->reset_gpio, 0); > + if (gpio_is_valid(hipcie->power_gpio)) > + gpio_set_value_cansleep(hipcie->power_gpio, 0); > } > > static int histb_pcie_host_enable(struct pcie_port *pp) > @@ -240,8 +243,14 @@ static int histb_pcie_host_enable(struct pcie_port *pp) > int ret; > > /* power on PCIe device if have */ > - if (gpio_is_valid(hipcie->reset_gpio)) > + if (gpio_is_valid(hipcie->power_gpio)) > + gpio_set_value_cansleep(hipcie->power_gpio, 1); > + > + if (gpio_is_valid(hipcie->reset_gpio)) { > + gpio_set_value_cansleep(hipcie->reset_gpio, 0); > + mdelay(10); > gpio_set_value_cansleep(hipcie->reset_gpio, 1); > + } > > ret = clk_prepare_enable(hipcie->bus_clk); > if (ret) { > @@ -335,15 +344,28 @@ static int histb_pcie_probe(struct platform_device *pdev) > return PTR_ERR(pci->dbi_base); > } > > + hipcie->power_gpio = of_get_named_gpio_flags(np, > + "power-gpios", 0, &of_flags); > + if (of_flags & OF_GPIO_ACTIVE_LOW) > + flag |= GPIOF_ACTIVE_LOW; Why isn't this inside the if statement? > + if (gpio_is_valid(hipcie->power_gpio)) { > + ret = devm_gpio_request_one(dev, hipcie->power_gpio, > + flag, "PCIe device power control"); > + if (ret) { > + dev_err(dev, "unable to request power gpio\n"); > + return ret; > + } > + } > + > hipcie->reset_gpio = of_get_named_gpio_flags(np, > "reset-gpios", 0, &of_flags); > if (of_flags & OF_GPIO_ACTIVE_LOW) > flag |= GPIOF_ACTIVE_LOW; > if (gpio_is_valid(hipcie->reset_gpio)) { > ret = devm_gpio_request_one(dev, hipcie->reset_gpio, > - flag, "PCIe device power control"); > + flag, "PCIe device reset control"); > if (ret) { > - dev_err(dev, "unable to request gpio\n"); > + dev_err(dev, "unable to request reset gpio\n"); > return ret; > } > } > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html