[U-Boot] [PATCH 06/21] usb: ehci: Add STi ehci support

[Simon Glass]

Hi Patrice,

On 3 April 2017 at 03:39, Patrice CHOTARD <patrice.chotard at st.com> wrote:
> Hi Simon
>
> On 04/01/2017 06:21 AM, Simon Glass wrote:
>> Hi Patrice,
>>
>> On 23 March 2017 at 03:59, Patrice CHOTARD <patrice.chotard at st.com> wrote:
>>> Hi Simon
>>>
>>> On 03/22/2017 02:05 PM, Simon Glass wrote:
>>>> Hi,
>>>>
>>>> On 17 March 2017 at 10:25,  <patrice.chotard at st.com> wrote:
>>>>> From: Patrice Chotard <patrice.chotard at st.com>
>>>>>
>>>>> Add support for on-chip ehci controller available
>>>>> on STMicrolectronics SoCs.
>>>>> ehci support will be then available on both type A
>>>>> USB 2.0 connectors.
>>>>>
>>>>> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
>>>>> ---
>>>>>  drivers/usb/host/Kconfig    |  9 +++++
>>>>>  drivers/usb/host/Makefile   |  1 +
>>>>>  drivers/usb/host/ehci-sti.c | 91 +++++++++++++++++++++++++++++++++++++++++++++
>>>>>  3 files changed, 101 insertions(+)
>>>>>  create mode 100644 drivers/usb/host/ehci-sti.c
>>>>>
>>>>> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>>>>> index 5129a57..d66f49e 100644
>>>>> --- a/drivers/usb/host/Kconfig
>>>>> +++ b/drivers/usb/host/Kconfig
>>>>> @@ -120,6 +120,15 @@ config USB_EHCI_MSM
>>>>>           This driver supports combination of Chipidea USB controller
>>>>>           and Synapsys USB PHY in host mode only.
>>>>>
>>>>> +config USB_EHCI_STI
>>>>> +       bool "Support for STMicroelectronics on-chip EHCI USB controller"
>>>>> +       depends on ARCH_STI
>>>>> +       select STI_PHY_USB
>>>>> +       default y
>>>>> +       ---help---
>>>>> +         Enables support for the on-chip EHCI controller on
>>>>> +         STMicroelectronics SoCs.
>>>>> +
>>>>>  config USB_EHCI_ZYNQ
>>>>>         bool "Support for Xilinx Zynq on-chip EHCI USB controller"
>>>>>         depends on ARCH_ZYNQ
>>>>> diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
>>>>> index 58c0cf5..303aa32 100644
>>>>> --- a/drivers/usb/host/Makefile
>>>>> +++ b/drivers/usb/host/Makefile
>>>>> @@ -46,6 +46,7 @@ obj-$(CONFIG_USB_EHCI_MARVELL) += ehci-marvell.o
>>>>>  obj-$(CONFIG_USB_EHCI_MSM) += ehci-msm.o
>>>>>  obj-$(CONFIG_USB_EHCI_PCI) += ehci-pci.o
>>>>>  obj-$(CONFIG_USB_EHCI_SPEAR) += ehci-spear.o
>>>>> +obj-$(CONFIG_USB_EHCI_STI) += ehci-sti.o
>>>>>  obj-$(CONFIG_USB_EHCI_SUNXI) += ehci-sunxi.o
>>>>>  obj-$(CONFIG_USB_EHCI_TEGRA) += ehci-tegra.o
>>>>>  obj-$(CONFIG_USB_EHCI_VCT) += ehci-vct.o
>>>>> diff --git a/drivers/usb/host/ehci-sti.c b/drivers/usb/host/ehci-sti.c
>>>>> new file mode 100644
>>>>> index 0000000..89ca66a
>>>>> --- /dev/null
>>>>> +++ b/drivers/usb/host/ehci-sti.c
>>>>> @@ -0,0 +1,91 @@
>>>>> +/*
>>>>> + * Copyright (c) 2017
>>>>> + * Patrice Chotard <patrice.chotard at st.com>
>>>>> + *
>>>>> + * SPDX-License-Identifier:    GPL-2.0+
>>>>> + */
>>>>> +
>>>>> +#include <common.h>
>>>>> +#include <asm/io.h>
>>>>> +#include <dm.h>
>>>>> +#include <errno.h>
>>>>> +#include "ehci.h"
>>>>> +#include <reset-uclass.h>
>>>>> +#include <usb.h>
>>>>> +
>>>>> +DECLARE_GLOBAL_DATA_PTR;
>>>>> +
>>>>> +struct sti_ehci_priv {
>>>>> +       struct ehci_ctrl ctrl;
>>>>> +       struct reset_ctl power_ctl;
>>>>> +       struct reset_ctl softreset_ctl;
>>>>> +};
>>>>> +
>>>>> +static int sti_ehci_probe(struct udevice *dev)
>>>>> +{
>>>>> +       struct sti_ehci_priv *priv = dev_get_priv(dev);
>>>>> +       struct ehci_hccr *hccr = priv->ctrl.hccr;
>>>>> +       struct ehci_hcor *hcor;
>>>>> +       struct udevice *dev_phy;
>>>>> +       int ret, phy_node;
>>>>> +
>>>>> +       hccr = (struct ehci_hccr *)dev_get_addr(dev);
>>>>> +
>>>>> +       if (hccr == (void *)FDT_ADDR_T_NONE)
>>>>> +               return -EINVAL;
>>>>> +
>>>>> +       ret = reset_get_by_name(dev, "power", &priv->power_ctl);
>>>>
>>>> This is OK, but can you instead access it via a phandle in the device's node?
>>>
>>> Sorry i didn't get your point. Why getting it using a phandle ?
>>
>> I mean that generally when a device needs another device this is
>> expressed by adding a phandle in the client device's node, or perhaps
>> some sort of name. That way it is possible (e.g.) to specify *which*
>> reset rather than hard-coding it.
>
> Agree with you, but i get one constraint. For this ehci IP, there are 2
> resets (power and softreset). I must identify each other to be able to
> assert/deassert them in the correct order.

One of those sounds like a reset. The other sounds like a regulator.

>
> I checked other U-boot drivers which already used reset, and all of them
> are using reset_get_by_name().

OK well it was a suggestion so will leave it to you. Is that how Linux
does it also?

Regards,
Simon