lkml.org 
[lkml]   [2014]   [Apr]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH V4 1/5] phy: Add new Exynos5 USB 3.0 PHY driver


    On Monday 14 April 2014 05:35 PM, Vivek Gautam wrote:
    > Hi Kishon,
    >
    >
    > On Mon, Apr 14, 2014 at 5:24 PM, Kishon Vijay Abraham I <kishon@ti.com> wrote:
    >> Hi,
    >>
    >> On Wednesday 09 April 2014 04:36 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 <gautam.vivek@samsung.com>
    >>>> ---
    >>>> .../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.
    >>>
    >>>> +- 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.
    >>>
    >>>> + 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".
    >>
    >> how about just adding depend_on OF in Kconfig?
    >
    > Already added a depend on 'OF'. Copying below the part of Kconfig in this patch.

    Alright.. Do we need the check then? If config_OF is enabled devices will be
    created using device tree no?

    Thanks
    Kishon


    \
     
     \ /
      Last update: 2014-04-14 15:21    [W:4.126 / U:0.332 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site