From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Sat, 10 May 2014 07:56:56 -0500 Subject: [PATCH v2 4/7] usb: ehci-platform: add optional reset controller retrieval In-Reply-To: <1399726619-30150-1-git-send-email-maxime.ripard@free-electrons.com> References: <1399726619-30150-1-git-send-email-maxime.ripard@free-electrons.com> Message-ID: <1399726619-30150-5-git-send-email-maxime.ripard@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Boris BREZILLON On the Allwinner's A31 SoC the reset line connected to the EHCI IP has to be deasserted for the EHCI block to be usable. Add support for an optional reset controller that will be deasserted on power off and asserted on power on. Signed-off-by: Boris BREZILLON Signed-off-by: Maxime Ripard Reviewed-by: Hans de Goede --- Documentation/devicetree/bindings/usb/usb-ehci.txt | 1 + drivers/usb/host/ehci-platform.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/Documentation/devicetree/bindings/usb/usb-ehci.txt b/Documentation/devicetree/bindings/usb/usb-ehci.txt index ff151ec084c4..43c1a4e06767 100644 --- a/Documentation/devicetree/bindings/usb/usb-ehci.txt +++ b/Documentation/devicetree/bindings/usb/usb-ehci.txt @@ -15,6 +15,7 @@ Optional properties: - clocks : a list of phandle + clock specifier pairs - phys : phandle + phy specifier pair - phy-names : "usb" + - resets : phandle + reset specifier pair Example (Sequoia 440EPx): ehci at e0000300 { diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c index c7dd93aad20c..da89f274aa76 100644 --- a/drivers/usb/host/ehci-platform.c +++ b/drivers/usb/host/ehci-platform.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include #include @@ -41,6 +42,7 @@ struct ehci_platform_priv { struct clk *clks[EHCI_MAX_CLKS]; + struct reset_control *rst; struct phy *phy; }; @@ -206,6 +208,19 @@ static int ehci_platform_probe(struct platform_device *dev) break; } } + + priv->rst = devm_reset_control_get_optional(&dev->dev, + NULL); + if (IS_ERR(priv->rst)) { + err = PTR_ERR(priv->rst); + if (err == -EPROBE_DEFER) + goto err_put_clks; + priv->rst = NULL; + } else { + err = reset_control_deassert(priv->rst); + if (err) + goto err_put_clks; + } } if (pdata->big_endian_desc) @@ -280,6 +295,9 @@ static int ehci_platform_remove(struct platform_device *dev) if (pdata->power_off) pdata->power_off(dev); + if (priv->rst) + reset_control_assert(priv->rst); + for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++) clk_put(priv->clks[clk]); -- 1.9.1