Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933130AbaDILt5 (ORCPT ); Wed, 9 Apr 2014 07:49:57 -0400 Received: from mail-qc0-f176.google.com ([209.85.216.176]:63665 "EHLO mail-qc0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932482AbaDILtx (ORCPT ); Wed, 9 Apr 2014 07:49:53 -0400 MIME-Version: 1.0 In-Reply-To: <534529B2.2020107@samsung.com> References: <1396967803-28868-1-git-send-email-gautam.vivek@samsung.com> <1396967803-28868-2-git-send-email-gautam.vivek@samsung.com> <534529B2.2020107@samsung.com> Date: Wed, 9 Apr 2014 17:19:52 +0530 X-Google-Sender-Auth: gBwduc-eYc9G3YbMYB-OLWNGW6I Message-ID: Subject: Re: [PATCH V4 1/5] phy: Add new Exynos5 USB 3.0 PHY driver From: Vivek Gautam To: Tomasz Figa Cc: Linux USB Mailing List , "linux-samsung-soc@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , linux-doc@vger.kernel.org, kishon , Greg KH , Felipe Balbi , Kukjin Kim , Kamil Debski , Jingoo Han , Sylwester Nawrocki Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Apr 9, 2014 at 4:36 PM, Tomasz Figa wrote: > Hi Vivek, > > Please see my comments inline. > > > On 08.04.2014 16:36, Vivek Gautam wrote: >> >> Add a new driver for the USB 3.0 PHY on Exynos5 series of SoCs. >> The new driver uses the generic PHY framework and will interact >> with DWC3 controller present on Exynos5 series of SoCs. >> Thereby, removing old phy-samsung-usb3 driver and related code >> used untill now which was based on usb/phy framework. >> >> Signed-off-by: Vivek Gautam >> --- >> .../devicetree/bindings/phy/samsung-phy.txt | 42 ++ >> drivers/phy/Kconfig | 11 + >> drivers/phy/Makefile | 1 + >> drivers/phy/phy-exynos5-usbdrd.c | 668 >> ++++++++++++++++++++ >> 4 files changed, 722 insertions(+) >> create mode 100644 drivers/phy/phy-exynos5-usbdrd.c > > > [snip] > > >> + Additional clock required for Exynos5420: >> + - usb30_sclk_100m: Additional special clock used for PHY operation >> + depicted as 'sclk_usbphy30' in CMU of >> Exynos5420. > > > Are you sure this isn't simply a gate for the ref clock, as it can be found > on another SoC that is not upstream yet? I don't have documentation for > Exynos 5420 so I can't tell, but I'd like to ask you to recheck this. >From what i can see in the manual : sclk_usbphy30 is derived from OSCCLK. It is coming from a MUX (default input line to this is OSCCLK) and then through a DIV there's this gate. {OSCCLK + other sources} --->[MUX] ---> [DIV] --> [GATE for sclk_usbphy30] the {rate of sclk_usbphy30} == OSCCLK However the 'ref' clock that we have been using is the actual oscillator clock. And on SoC Exynos5250, we don't have any such gate (sclk_usbphy30). So should this mean that ref clock and sclk_usbphy30 are still be controlled by two different gates ? > > >> +- samsung,syscon-phandle: phandle for syscon interface, which is used to >> + control pmu registers for power isolation. >> +- samsung,pmu-offset: phy power control register offset to >> pmu-system-controller >> + base. >> +- #phy-cells : from the generic PHY bindings, must be 1; >> + >> +For "samsung,exynos5250-usbdrd-phy" and "samsung,exynos5420-usbdrd-phy" >> +compatible PHYs, the second cell in the PHY specifier identifies the >> +PHY id, which is interpreted as follows: >> + 0 - UTMI+ type phy, >> + 1 - PIPE3 type phy, >> + >> +Example: >> + usb3_phy: usbphy@12100000 { >> + compatible = "samsung,exynos5250-usbdrd-phy"; >> + reg = <0x12100000 0x100>; >> + clocks = <&clock 286>, <&clock 1>; >> + clock-names = "phy", "usb3phy_refclk"; > > > Binding description above doesn't mention "usb3phy_refclk" entry. my bad !! will correct this. > > >> + samsung,syscon-phandle = <&pmu_syscon>; >> + samsung,pmu-offset = <0x704>; >> + #phy-cells = <1>; >> + }; > > > [snip] > > >> diff --git a/drivers/phy/phy-exynos5-usbdrd.c >> b/drivers/phy/phy-exynos5-usbdrd.c >> new file mode 100644 >> index 0000000..ff54a7c >> --- /dev/null >> +++ b/drivers/phy/phy-exynos5-usbdrd.c > > > [snip] > > >> +static int exynos5_usbdrd_phy_probe(struct platform_device *pdev) >> +{ >> + struct device *dev = &pdev->dev; >> + struct device_node *node = dev->of_node; >> + struct exynos5_usbdrd_phy *phy_drd; >> + struct phy_provider *phy_provider; >> + struct resource *res; >> + const struct of_device_id *match; >> + const struct exynos5_usbdrd_phy_drvdata *drv_data; >> + struct regmap *reg_pmu; >> + u32 pmu_offset; >> + int i; >> + >> + /* >> + * Exynos systems are completely DT enabled, >> + * so lets not have any platform data support for this driver. >> + */ >> + if (!node) { >> + dev_err(dev, "no device node found\n"); > > > This error message is not very meaningful. I'd rather use something like > "This driver can be only instantiated using Device Tree". Sure, will amend this. > > >> + return -ENODEV; >> + } >> + >> + match = of_match_node(exynos5_usbdrd_phy_of_match, >> pdev->dev.of_node); >> + if (!match) { >> + dev_err(dev, "of_match_node() failed\n"); >> + return -EINVAL; >> + } >> + drv_data = match->data; >> + >> + phy_drd = devm_kzalloc(dev, sizeof(*phy_drd), GFP_KERNEL); >> + if (!phy_drd) >> + return -ENOMEM; >> + >> + dev_set_drvdata(dev, phy_drd); >> + phy_drd->dev = dev; >> + >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + phy_drd->reg_phy = devm_ioremap_resource(dev, res); >> + if (IS_ERR(phy_drd->reg_phy)) { >> + dev_err(dev, "Failed to map register memory (phy)\n"); > > > devm_ioremap_resource() already prints an error message. Ok, will remove this message. > > Best regards, > Tomasz > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/