| Message ID | 1389198608-24339-3-git-send-email-hdegoede@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 08, 2014 at 05:30:08PM +0100, Hans de Goede wrote: > Currently ehci-platform is only used in combination with devicetree when used > with some via socs. By extending it to (optionally) get clks and a phy from > devicetree, and enabling / disabling those on power_on / off, it can be used > more generically. Specifically after this commit it can be used for the > ehci controller on Allwinner sunxi SoCs. > > Somehow we've ended up with 2 device-bindings documents for ehci-platform.c, > this patch renames and updates one to platform-ehci.txt to reflect that this > is a generic platform driver, and removes the other. > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > --- > .../devicetree/bindings/usb/platform-ehci.txt | 25 ++++ > .../devicetree/bindings/usb/via,vt8500-ehci.txt | 15 --- > .../devicetree/bindings/usb/vt8500-ehci.txt | 12 -- > drivers/usb/host/ehci-platform.c | 126 +++++++++++++++++---- > 4 files changed, 131 insertions(+), 47 deletions(-) > create mode 100644 Documentation/devicetree/bindings/usb/platform-ehci.txt > delete mode 100644 Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt > delete mode 100644 Documentation/devicetree/bindings/usb/vt8500-ehci.txt > > diff --git a/Documentation/devicetree/bindings/usb/platform-ehci.txt b/Documentation/devicetree/bindings/usb/platform-ehci.txt > new file mode 100644 > index 0000000..56c478d > --- /dev/null > +++ b/Documentation/devicetree/bindings/usb/platform-ehci.txt > @@ -0,0 +1,25 @@ > +Generic Platform EHCI controller > + > +Required properties: > +- compatible : "via,vt8500-ehci" or "wm,prizm-ehci" > +- reg : ehci controller register range (address and length) > +- interrupts : ehci controller interrupt > + > +Optional properties: > +- clocks : a list of phandle + clock specifier pairs, one for each entry > + in clock-names. > +- clock-names : "clk0", "clk1", ... > +- phys : phy > +- phy-names : "phy0" > + > +Example: > + > + ehci@d8007900 { > + compatible = "via,vt8500-ehci"; > + reg = <0xd8007900 0x200>; > + interrupts = <43>; > + clocks = <&usb_clk 6>, <&ahb_gates 2>; > + clock-names = "clk0", "clk1"; I'm really not convinced by this either. It prevents you from doing anything useful out of these clocks, and the only thing you can actually do with it is calling clk_get, and that's pretty much it. What if you some platform needs to adjust the rate of one of the two? Or wants to cut one but not the other for any reason? You're just screwed, and you can do anything about it, because you have no way of telling what "clk0" is used for. Especially, since what you really want is to access the clocks by index, that you can do with of_clk_get. Calling it "bus" and "phy" or whatever it's used for both provide a way of differentiating the two, yet being rather generic. And if we need to add a third one, I'm pretty sure we will be able to come up with a generic name then. Maxime
Hi, On 01/08/2014 07:16 PM, Maxime Ripard wrote: > On Wed, Jan 08, 2014 at 05:30:08PM +0100, Hans de Goede wrote: >> Currently ehci-platform is only used in combination with devicetree when used >> with some via socs. By extending it to (optionally) get clks and a phy from >> devicetree, and enabling / disabling those on power_on / off, it can be used >> more generically. Specifically after this commit it can be used for the >> ehci controller on Allwinner sunxi SoCs. >> >> Somehow we've ended up with 2 device-bindings documents for ehci-platform.c, >> this patch renames and updates one to platform-ehci.txt to reflect that this >> is a generic platform driver, and removes the other. >> >> Signed-off-by: Hans de Goede <hdegoede@redhat.com> >> --- >> .../devicetree/bindings/usb/platform-ehci.txt | 25 ++++ >> .../devicetree/bindings/usb/via,vt8500-ehci.txt | 15 --- >> .../devicetree/bindings/usb/vt8500-ehci.txt | 12 -- >> drivers/usb/host/ehci-platform.c | 126 +++++++++++++++++---- >> 4 files changed, 131 insertions(+), 47 deletions(-) >> create mode 100644 Documentation/devicetree/bindings/usb/platform-ehci.txt >> delete mode 100644 Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt >> delete mode 100644 Documentation/devicetree/bindings/usb/vt8500-ehci.txt >> >> diff --git a/Documentation/devicetree/bindings/usb/platform-ehci.txt b/Documentation/devicetree/bindings/usb/platform-ehci.txt >> new file mode 100644 >> index 0000000..56c478d >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/usb/platform-ehci.txt >> @@ -0,0 +1,25 @@ >> +Generic Platform EHCI controller >> + >> +Required properties: >> +- compatible : "via,vt8500-ehci" or "wm,prizm-ehci" >> +- reg : ehci controller register range (address and length) >> +- interrupts : ehci controller interrupt >> + >> +Optional properties: >> +- clocks : a list of phandle + clock specifier pairs, one for each entry >> + in clock-names. >> +- clock-names : "clk0", "clk1", ... >> +- phys : phy >> +- phy-names : "phy0" >> + >> +Example: >> + >> + ehci@d8007900 { >> + compatible = "via,vt8500-ehci"; >> + reg = <0xd8007900 0x200>; >> + interrupts = <43>; >> + clocks = <&usb_clk 6>, <&ahb_gates 2>; >> + clock-names = "clk0", "clk1"; > > I'm really not convinced by this either. It prevents you from doing > anything useful out of these clocks, and the only thing you can > actually do with it is calling clk_get, and that's pretty much it. > > What if you some platform needs to adjust the rate of one of the two? Then it needs its own driver. This is intended as a binding for a *generic* driver, which is meant to cover simple straight forward non-pci ohci cases. For more complex cases a separate driver will need to be written. I must say I'm becoming a bit unhappy with how the reviews of devicetree bindings are being done. In one case it is not generic enough (ahci-sunxi). If I then try to make it more generic in a case where that can actually be done as the hardware is pretty straight forward, it is not specific enough. You can simply not have both! > Or wants to cut one but not the other for any reason? This is another example of non generic behavior, requiring a separate (small using the existing ohci core) platform glue driver, like the *19* we already have. Regards, Hans
On Thu, 9 Jan 2014, Hans de Goede wrote: > >> +Optional properties: > >> +- clocks : a list of phandle + clock specifier pairs, one for each entry > >> + in clock-names. > >> +- clock-names : "clk0", "clk1", ... > >> +- phys : phy > >> +- phy-names : "phy0" > >> + > >> +Example: > >> + > >> + ehci@d8007900 { > >> + compatible = "via,vt8500-ehci"; > >> + reg = <0xd8007900 0x200>; > >> + interrupts = <43>; > >> + clocks = <&usb_clk 6>, <&ahb_gates 2>; > >> + clock-names = "clk0", "clk1"; > > > > I'm really not convinced by this either. It prevents you from doing > > anything useful out of these clocks, and the only thing you can > > actually do with it is calling clk_get, and that's pretty much it. > > > > What if you some platform needs to adjust the rate of one of the two? > > Then it needs its own driver. This is intended as a binding for a > *generic* driver, which is meant to cover simple straight forward > non-pci ohci cases. For more complex cases a separate driver will > need to be written. > > I must say I'm becoming a bit unhappy with how the reviews of devicetree > bindings are being done. In one case it is not generic enough (ahci-sunxi). > > If I then try to make it more generic in a case where that can actually > be done as the hardware is pretty straight forward, it is not specific enough. > You can simply not have both! > > > Or wants to cut one but not the other for any reason? > > This is another example of non generic behavior, requiring a separate > (small using the existing ohci core) platform glue driver, like the *19* we > already have. Would DT allow ehci-platform.c to access the clocks by their index in the array, rather than by name? After all, you don't really care about the names at all, since the driver knows nothing about the clocks' functions. The same is true of the phy entry. Alan Stern
Hi, On 01/09/2014 04:47 PM, Alan Stern wrote: > On Thu, 9 Jan 2014, Hans de Goede wrote: > >>>> +Optional properties: >>>> +- clocks : a list of phandle + clock specifier pairs, one for each entry >>>> + in clock-names. >>>> +- clock-names : "clk0", "clk1", ... >>>> +- phys : phy >>>> +- phy-names : "phy0" >>>> + >>>> +Example: >>>> + >>>> + ehci@d8007900 { >>>> + compatible = "via,vt8500-ehci"; >>>> + reg = <0xd8007900 0x200>; >>>> + interrupts = <43>; >>>> + clocks = <&usb_clk 6>, <&ahb_gates 2>; >>>> + clock-names = "clk0", "clk1"; >>> >>> I'm really not convinced by this either. It prevents you from doing >>> anything useful out of these clocks, and the only thing you can >>> actually do with it is calling clk_get, and that's pretty much it. >>> >>> What if you some platform needs to adjust the rate of one of the two? >> >> Then it needs its own driver. This is intended as a binding for a >> *generic* driver, which is meant to cover simple straight forward >> non-pci ohci cases. For more complex cases a separate driver will >> need to be written. >> >> I must say I'm becoming a bit unhappy with how the reviews of devicetree >> bindings are being done. In one case it is not generic enough (ahci-sunxi). >> >> If I then try to make it more generic in a case where that can actually >> be done as the hardware is pretty straight forward, it is not specific enough. >> You can simply not have both! >> >>> Or wants to cut one but not the other for any reason? >> >> This is another example of non generic behavior, requiring a separate >> (small using the existing ohci core) platform glue driver, like the *19* we >> already have. > > Would DT allow ehci-platform.c to access the clocks by their index in > the array, rather than by name? After all, you don't really care about > the names at all, since the driver knows nothing about the clocks' > functions. Yes, actually I've been discussing this with Maxime on irc and I'm just done preparing a v3 doing exactly that. I was just checking mail for any more review comments before pushing out v3 :) > The same is true of the phy entry. The phy entry must have a name, this is specified in the phy bindings in Documentation/devicetree/bindings/phy/phy-bindings.txt: """ PHY user node ============= Required Properties: phys : the phandle for the PHY device (used by the PHY subsystem) phy-names : the names of the PHY corresponding to the PHYs present in the *phys* phandle """ Now that I've dropped the clock-names, I've changed the ugly "phy0" name to "usb" as the phy pointed to is supposed to be an usb phy. Regards, Hans
diff --git a/Documentation/devicetree/bindings/usb/platform-ehci.txt b/Documentation/devicetree/bindings/usb/platform-ehci.txt new file mode 100644 index 0000000..56c478d --- /dev/null +++ b/Documentation/devicetree/bindings/usb/platform-ehci.txt @@ -0,0 +1,25 @@ +Generic Platform EHCI controller + +Required properties: +- compatible : "via,vt8500-ehci" or "wm,prizm-ehci" +- reg : ehci controller register range (address and length) +- interrupts : ehci controller interrupt + +Optional properties: +- clocks : a list of phandle + clock specifier pairs, one for each entry + in clock-names. +- clock-names : "clk0", "clk1", ... +- phys : phy +- phy-names : "phy0" + +Example: + + ehci@d8007900 { + compatible = "via,vt8500-ehci"; + reg = <0xd8007900 0x200>; + interrupts = <43>; + clocks = <&usb_clk 6>, <&ahb_gates 2>; + clock-names = "clk0", "clk1"; + phys = <&usbphy 1>; + phy-names = "phy0"; + }; diff --git a/Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt b/Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt deleted file mode 100644 index 17b3ad1..0000000 --- a/Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt +++ /dev/null @@ -1,15 +0,0 @@ -VIA/Wondermedia VT8500 EHCI Controller ------------------------------------------------------ - -Required properties: -- compatible : "via,vt8500-ehci" -- reg : Should contain 1 register ranges(address and length) -- interrupts : ehci controller interrupt - -Example: - - ehci@d8007900 { - compatible = "via,vt8500-ehci"; - reg = <0xd8007900 0x200>; - interrupts = <43>; - }; diff --git a/Documentation/devicetree/bindings/usb/vt8500-ehci.txt b/Documentation/devicetree/bindings/usb/vt8500-ehci.txt deleted file mode 100644 index 5fb8fd6..0000000 --- a/Documentation/devicetree/bindings/usb/vt8500-ehci.txt +++ /dev/null @@ -1,12 +0,0 @@ -VIA VT8500 and Wondermedia WM8xxx SoC USB controllers. - -Required properties: - - compatible: Should be "via,vt8500-ehci" or "wm,prizm-ehci". - - reg: Address range of the ehci registers. size should be 0x200 - - interrupts: Should contain the ehci interrupt. - -usb: ehci@D8007100 { - compatible = "wm,prizm-ehci", "usb-ehci"; - reg = <0xD8007100 0x200>; - interrupts = <1>; -}; diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c index 7f30b71..ce76659 100644 --- a/drivers/usb/host/ehci-platform.c +++ b/drivers/usb/host/ehci-platform.c @@ -3,6 +3,7 @@ * * Copyright 2007 Steven Brown <sbrown@cortland.com> * Copyright 2010-2012 Hauke Mehrtens <hauke@hauke-m.de> + * Copyright 2014 Hans de Goede <hdegoede@redhat.com> * * Derived from the ohci-ssb driver * Copyright 2007 Michael Buesch <m@bues.ch> @@ -18,6 +19,7 @@ * * Licensed under the GNU/GPL. See COPYING for details. */ +#include <linux/clk.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/kernel.h> @@ -25,6 +27,7 @@ #include <linux/io.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/phy/phy.h> #include <linux/platform_device.h> #include <linux/usb.h> #include <linux/usb/hcd.h> @@ -34,6 +37,12 @@ #define DRIVER_DESC "EHCI generic platform driver" +#define EHCI_MAX_CLKS 3 +struct ehci_platform_priv { + struct clk *clks[EHCI_MAX_CLKS]; + struct phy *phy; +}; + static const char hcd_name[] = "ehci-platform"; static int ehci_platform_reset(struct usb_hcd *hcd) @@ -64,28 +73,84 @@ static int ehci_platform_reset(struct usb_hcd *hcd) return 0; } +static int ehci_platform_power_on(struct platform_device *dev) +{ + struct usb_hcd *hcd = platform_get_drvdata(dev); + struct ehci_platform_priv *priv = + (struct ehci_platform_priv *)hcd_to_ehci(hcd)->priv; + int clk, ret; + + for (clk = 0; priv->clks[clk] && clk < EHCI_MAX_CLKS; clk++) { + ret = clk_prepare_enable(priv->clks[clk]); + if (ret) + goto err_disable_clks; + } + + if (priv->phy) { + ret = phy_init(priv->phy); + if (ret) + goto err_disable_clks; + + ret = phy_power_on(priv->phy); + if (ret) + goto err_exit_phy; + } + + return 0; + +err_exit_phy: + phy_exit(priv->phy); +err_disable_clks: + while (--clk >= 0) + clk_disable_unprepare(priv->clks[clk]); + + return ret; +} + +static void ehci_platform_power_off(struct platform_device *dev) +{ + struct usb_hcd *hcd = platform_get_drvdata(dev); + struct ehci_platform_priv *priv = + (struct ehci_platform_priv *)hcd_to_ehci(hcd)->priv; + int clk; + + if (priv->phy) { + phy_power_off(priv->phy); + phy_exit(priv->phy); + } + + for (clk = EHCI_MAX_CLKS - 1; clk >= 0; clk--) + if (priv->clks[clk]) + clk_disable_unprepare(priv->clks[clk]); +} + static struct hc_driver __read_mostly ehci_platform_hc_driver; static const struct ehci_driver_overrides platform_overrides __initconst = { - .reset = ehci_platform_reset, + .reset = ehci_platform_reset, + .extra_priv_size = sizeof(struct ehci_platform_priv), }; -static struct usb_ehci_pdata ehci_platform_defaults; +static struct usb_ehci_pdata ehci_platform_defaults = { + .power_on = ehci_platform_power_on, + .power_suspend = ehci_platform_power_off, + .power_off = ehci_platform_power_off, +}; static int ehci_platform_probe(struct platform_device *dev) { struct usb_hcd *hcd; struct resource *res_mem; struct usb_ehci_pdata *pdata; - int irq; - int err; + int clk, irq, err; + char name[8]; if (usb_disabled()) return -ENODEV; /* - * use reasonable defaults so platforms don't have to provide these. - * with DT probing on ARM, none of these are set. + * Use reasonable defaults so platforms don't have to provide these + * with DT probing on ARM. */ if (!dev_get_platdata(&dev->dev)) dev->dev.platform_data = &ehci_platform_defaults; @@ -107,17 +172,40 @@ static int ehci_platform_probe(struct platform_device *dev) return -ENXIO; } + hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev, + dev_name(&dev->dev)); + if (!hcd) + return -ENOMEM; + + if (pdata == &ehci_platform_defaults) { + struct ehci_platform_priv *priv = (struct ehci_platform_priv *) + hcd_to_ehci(hcd)->priv; + + priv->phy = devm_phy_get(&dev->dev, "phy0"); + if (IS_ERR(priv->phy)) { + err = PTR_ERR(priv->phy); + if (err == -EPROBE_DEFER) + goto err_put_hcd; + priv->phy = NULL; + } + + for (clk = 0; clk < EHCI_MAX_CLKS; clk++) { + snprintf(name, sizeof(name), "clk%d", clk); + priv->clks[clk] = devm_clk_get(&dev->dev, name); + if (IS_ERR(priv->clks[clk])) { + err = PTR_ERR(priv->clks[clk]); + if (err == -EPROBE_DEFER) + goto err_put_hcd; + priv->clks[clk] = NULL; + } + } + } + + platform_set_drvdata(dev, hcd); if (pdata->power_on) { err = pdata->power_on(dev); if (err < 0) - return err; - } - - hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev, - dev_name(&dev->dev)); - if (!hcd) { - err = -ENOMEM; - goto err_power; + goto err_put_hcd; } hcd->rsrc_start = res_mem->start; @@ -126,21 +214,19 @@ static int ehci_platform_probe(struct platform_device *dev) hcd->regs = devm_ioremap_resource(&dev->dev, res_mem); if (IS_ERR(hcd->regs)) { err = PTR_ERR(hcd->regs); - goto err_put_hcd; + goto err_power; } err = usb_add_hcd(hcd, irq, IRQF_SHARED); if (err) - goto err_put_hcd; - - platform_set_drvdata(dev, hcd); + goto err_power; return err; -err_put_hcd: - usb_put_hcd(hcd); err_power: if (pdata->power_off) pdata->power_off(dev); +err_put_hcd: + usb_put_hcd(hcd); return err; }
Currently ehci-platform is only used in combination with devicetree when used with some via socs. By extending it to (optionally) get clks and a phy from devicetree, and enabling / disabling those on power_on / off, it can be used more generically. Specifically after this commit it can be used for the ehci controller on Allwinner sunxi SoCs. Somehow we've ended up with 2 device-bindings documents for ehci-platform.c, this patch renames and updates one to platform-ehci.txt to reflect that this is a generic platform driver, and removes the other. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- .../devicetree/bindings/usb/platform-ehci.txt | 25 ++++ .../devicetree/bindings/usb/via,vt8500-ehci.txt | 15 --- .../devicetree/bindings/usb/vt8500-ehci.txt | 12 -- drivers/usb/host/ehci-platform.c | 126 +++++++++++++++++---- 4 files changed, 131 insertions(+), 47 deletions(-) create mode 100644 Documentation/devicetree/bindings/usb/platform-ehci.txt delete mode 100644 Documentation/devicetree/bindings/usb/via,vt8500-ehci.txt delete mode 100644 Documentation/devicetree/bindings/usb/vt8500-ehci.txt