[PATCH 2/2] usb: host: xhci-plat: Fix clock resource by adding a register clock
Gregory CLEMENT
gregory.clement at bootlin.com
Tue Mar 13 03:58:50 PDT 2018
Hi Rob,
On mer., févr. 28 2018, Mathias Nyman <mathias.nyman at intel.com> wrote:
> On 14.02.2018 18:16, Gregory CLEMENT wrote:
>> On Armada 7K/8K we need to explicitly enable the register clock. This
>> clock is optional because not all the SoCs using this IP need it but at
>> least for Armada 7K/8K it is actually mandatory.
>>
>> The change was done at xhci-plat level and not at a xhci-mvebu.c because,
>> it is expected that other SoC would have this kind of constraint.
>>
>> The binding documentation is updating accordingly.
>>
>> Signed-off-by: Gregory CLEMENT <gregory.clement at bootlin.com>
>> ---
>> Documentation/devicetree/bindings/usb/usb-xhci.txt | 5 +++-
>> drivers/usb/host/xhci-plat.c | 33 ++++++++++++++++++----
>> drivers/usb/host/xhci.h | 3 +-
>> 3 files changed, 33 insertions(+), 8 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt
>> index e2ea59bbca93..e4b14511f4f8 100644
>> --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
>> +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
>> @@ -27,7 +27,10 @@ Required properties:
>> - interrupts: one XHCI interrupt should be described here.
>> Optional properties:
>> - - clocks: reference to a clock
>> + - clocks: reference to the clocks
>> + - clock-names: mandatory if there is a second clock, in this case
>> + the name must be "core" for the first clock and "reg" for the
>> + second one
>> - usb2-lpm-disable: indicate if we don't want to enable USB2 HW LPM
>> - usb3-lpm-capable: determines if platform is USB3 LPM capable
>> - quirk-broken-port-ped: set if the controller has broken port disable mechanism
>
> Would be good to get a Ack or review by Rob Herring for the above
Would you mind to have a look on this binding update ?
Initially I didn't copy you trying to not overflow you because this
change is only about adding a new clock, which is pretty common. But I
think Mathias would be more confident with a Ack or review by you.
Thanks,
Gregory
>
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 79afaac57ef6..fd0c399013a2 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -157,6 +157,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
>> struct resource *res;
>> struct usb_hcd *hcd;
>> struct clk *clk;
>> + struct clk *reg_clk;
>> int ret;
>> int irq;
>> @@ -226,17 +227,27 @@ static int xhci_plat_probe(struct
>> platform_device *pdev)
>> hcd->rsrc_len = resource_size(res);
>> /*
>> - * Not all platforms have a clk so it is not an error if the
>> - * clock does not exists.
>> + * Not all platforms have clks so it is not an error if the
>> + * clock do not exist.
>> */
>> + reg_clk = devm_clk_get(&pdev->dev, "reg");
>> + if (!IS_ERR(reg_clk)) {
>> + ret = clk_prepare_enable(reg_clk);
>> + if (ret)
>> + goto put_hcd;
>> + } else if (PTR_ERR(reg_clk) == -EPROBE_DEFER) {
>> + ret = -EPROBE_DEFER;
>> + goto put_hcd;
>> + }
>> +
>> clk = devm_clk_get(&pdev->dev, NULL);
>> if (!IS_ERR(clk)) {
>> ret = clk_prepare_enable(clk);
>> if (ret)
>> - goto put_hcd;
>> + goto disable_reg_clk;
>> } else if (PTR_ERR(clk) == -EPROBE_DEFER) {
>> ret = -EPROBE_DEFER;
>> - goto put_hcd;
>> + goto disable_reg_clk;
>> }
>> xhci = hcd_to_xhci(hcd);
>> @@ -252,6 +263,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
>> device_wakeup_enable(hcd->self.controller);
>> xhci->clk = clk;
>> + xhci->reg_clk = reg_clk;
>> xhci->main_hcd = hcd;
>> xhci->shared_hcd = __usb_create_
>
> hcd(driver, sysdev, &pdev->dev,
>> dev_name(&pdev->dev), hcd);
>> @@ -321,6 +333,9 @@ static int xhci_plat_probe(struct platform_device *pdev)
>> disable_clk:
>> clk_disable_unprepare(clk);
>> +disable_reg_clk:
>> + clk_disable_unprepare(reg_clk);
>> +
>> put_hcd:
>> usb_put_hcd(hcd);
>> @@ -336,6 +351,7 @@ static int xhci_plat_remove(struct
>> platform_device *dev)
>> struct usb_hcd *hcd = platform_get_drvdata(dev);
>> struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>> struct clk *clk = xhci->clk;
>> + struct clk *reg_clk = xhci->reg_clk;
>> xhci->xhc_state |= XHCI_STATE_REMOVING;
>> @@ -346,6 +362,7 @@ static int xhci_plat_remove(struct
>> platform_device *dev)
>> usb_put_hcd(xhci->shared_hcd);
>> clk_disable_unprepare(clk);
>> + clk_disable_unprepare(reg_clk);
>> usb_put_hcd(hcd);
>> pm_runtime_set_suspended(&dev->dev);
>> @@ -370,8 +387,10 @@ static int __maybe_unused xhci_plat_suspend(struct device *dev)
>> */
>> ret = xhci_suspend(xhci, device_may_wakeup(dev));
>> - if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk))
>> + if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk)) {
>> clk_disable_unprepare(xhci->clk);
>> + clk_disable_unprepare(xhci->reg_clk);
>> + }
>> return ret;
>> }
>> @@ -382,8 +401,10 @@ static int __maybe_unused xhci_plat_resume(struct device *dev)
>> struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>> int ret;
>> - if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk))
>> + if (!device_may_wakeup(dev) && !IS_ERR(xhci->clk)) {
>> + clk_prepare_enable(xhci->reg_clk);
>> clk_prepare_enable(xhci->clk);
>> + }
>> ret = xhci_priv_resume_quirk(hcd);
>> if (ret)
>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
>> index 96099a245c69..9884aaba1b40 100644
>> --- a/drivers/usb/host/xhci.h
>> +++ b/drivers/usb/host/xhci.h
>> @@ -1726,8 +1726,9 @@ struct xhci_hcd {
>> int page_shift;
>> /* msi-x vectors */
>> int msix_count;
>> - /* optional clock */
>> + /* optional clocks */
>> struct clk *clk;
>> + struct clk *reg_clk;
>> /* data structures */
>> struct xhci_device_context_array *dcbaa;
>> struct xhci_ring *cmd_ring;
>>
>
> Looks good to me, I'll queue it up if the devicetree bindings looks ok for Rob Herring
>
> -Mathias
>
--
Gregory Clement, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
http://bootlin.com
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