[PATCH u-boot 1/3] usb: host: Add simple of glue driver for DWC3 USB Controllers integration
Marek Vasut
marex at denx.de
Thu Mar 29 07:24:40 PDT 2018
On 03/29/2018 04:23 PM, Neil Armstrong wrote:
> On 29/03/2018 15:52, Marek Vasut wrote:
>> On 03/29/2018 03:42 PM, Neil Armstrong wrote:
>>> Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
>>> ---
>>> drivers/usb/host/Kconfig | 7 ++
>>> drivers/usb/host/Makefile | 1 +
>>> drivers/usb/host/dwc3-of-simple.c | 187 ++++++++++++++++++++++++++++++++++++++
>>> 3 files changed, 195 insertions(+)
>>> create mode 100644 drivers/usb/host/dwc3-of-simple.c
>>>
>>> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>>> index a7249b7..6caa615 100644
>>> --- a/drivers/usb/host/Kconfig
>>> +++ b/drivers/usb/host/Kconfig
>>> @@ -21,6 +21,13 @@ config USB_XHCI_DWC3
>>> Say Y or if your system has a Dual Role SuperSpeed
>>> USB controller based on the DesignWare USB3 IP Core.
>>>
>>> +config USB_XHCI_DWC3_OF_SIMPLE
>>> + bool "DesignWare USB3 DRD Generic OF Simple Glue Layer"
>>> + select MISC
>>> + help
>>> + Support USB2/3 functionality in simple SoC integrations with
>>> + USB controller based on the DesignWare USB3 IP Core.
>>> +
>>> config USB_XHCI_MVEBU
>>> bool "MVEBU USB 3.0 support"
>>> default y
>>> diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
>>> index 9819489..abe4f90 100644
>>> --- a/drivers/usb/host/Makefile
>>> +++ b/drivers/usb/host/Makefile
>>> @@ -49,6 +49,7 @@ obj-$(CONFIG_USB_EHCI_ZYNQ) += ehci-zynq.o
>>> # xhci
>>> obj-$(CONFIG_USB_XHCI_HCD) += xhci.o xhci-mem.o xhci-ring.o
>>> obj-$(CONFIG_USB_XHCI_DWC3) += xhci-dwc3.o
>>> +obj-$(CONFIG_USB_XHCI_DWC3_OF_SIMPLE) += dwc3-of-simple.o
>>> obj-$(CONFIG_USB_XHCI_ROCKCHIP) += xhci-rockchip.o
>>> obj-$(CONFIG_USB_XHCI_ZYNQMP) += xhci-zynqmp.o
>>> obj-$(CONFIG_USB_XHCI_KEYSTONE) += xhci-keystone.o
>>> diff --git a/drivers/usb/host/dwc3-of-simple.c b/drivers/usb/host/dwc3-of-simple.c
>>> new file mode 100644
>>> index 0000000..826a996
>>> --- /dev/null
>>> +++ b/drivers/usb/host/dwc3-of-simple.c
>>> @@ -0,0 +1,187 @@
>>> +/*
>>> + * dwc3-of-simple.c - OF glue layer for simple integrations
>>> + *
>>> + * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
>>> + *
>>> + * Author: Felipe Balbi <balbi at ti.com>
>>> + *
>>> + * Copyright (C) 2018 BayLibre, SAS
>>> + * Author: Neil Armstrong <narmstron at baylibre.com>
>>> + *
>>> + * SPDX-License-Identifier: GPL-2.0+
>>> + */
>>> +
>>> +#include <common.h>
>>> +#include <dm.h>
>>> +#include <fdtdec.h>
>>> +#include <reset.h>
>>> +#include <clk.h>
>>> +
>>> +DECLARE_GLOBAL_DATA_PTR;
>>> +
>>> +struct dwc3_of_simple {
>>> +#if CONFIG_IS_ENABLED(CLK)
>>> + struct clk *clks;
>>> + int num_clocks;
>>> +#endif
>>> +#if CONFIG_IS_ENABLED(DM_RESET)
>>> + struct reset_ctl *resets;
>>> + int num_resets;
>>> +#endif
>>> +};
>>> +
>>> +#if CONFIG_IS_ENABLED(DM_RESET)
>>> +static int dwc3_of_simple_reset_init(struct udevice *dev,
>>> + struct dwc3_of_simple *simple,
>>> + int count)
>>> +{
>>> + int i, ret, err;
>>> +
>>> + if (!count)
>>> + return 0;
>>> +
>>> + simple->resets = devm_kcalloc(dev, count, sizeof(struct reset_ctl),
>>> + GFP_KERNEL);
>>> + if (!simple->resets)
>>> + return -ENOMEM;
>>> +
>>> + for (i = 0; i < count; i++) {
>>> + ret = reset_get_by_index(dev, i, &simple->resets[i]);
>>> + if (ret < 0)
>>> + break;
>>> +
>>> + ret = reset_request(&simple->resets[i]);
>>> + if (ret) {
>>> + pr_err("failed to request reset line %d\n", i);
>>> + reset_free(&simple->resets[i]);
>>> + goto reset_err;
>>> + }
>>> +
>>> +
>>> + ++simple->num_resets;
>>> + }
>>> +
>>> + for (i = 0; i < simple->num_resets; i++) {
>>> + ret = reset_deassert(&simple->resets[i]);
>>> + if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
>>> + pr_err("failed to deassert reset line %d\n", i);
>>> + goto reset_err;
>>> + }
>>> + }
>>> +
>>> + return 0;
>>
>> This looks like some driver I've seen before. Isn't there similar code
>> for simple EHCI or OHCI driver already ?
>>
>
> Hi,
>
> This is not an EHCI/OHCI driver, only the glue to init the clocks and reset,
> it's the exact same as the drivers/usb/dwc3/dwc3-of-simple.c adapted to U-Boot.
>
> yes, similar code exists in drivers/usb/host/ehci-generic.c and
> drivers/usb/host/ohci-generic.c but the goal here is not to initialize the controller
> but only the glue.
Can't we recycle that code instead of having three copies of similar stuff ?
--
Best regards,
Marek Vasut
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