[PATCH 3/9] USB: add devicetree helpers for determining dr_mode and phy_type

[Alexander Shishkin]

Sascha Hauer <s.hauer at pengutronix.de> writes:

> From: Michael Grzeschik <m.grzeschik at pengutronix.de>
>
> This adds two little devicetree helper functions for determining the
> dr_mode (host, peripheral, otg) and phy_type (utmi, ulpi,...) from
> the devicetree.
>
> Signed-off-by: Michael Grzeschik <m.grzeschik at pengutronix.de>
> Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  drivers/usb/phy/Makefile |    1 +
>  drivers/usb/phy/of.c     |   47 ++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/usb-common.c |   36 +++++++++++++++++++++++++++++++++++
>  include/linux/usb/of.h   |   27 ++++++++++++++++++++++++++
>  include/linux/usb/otg.h  |    7 +++++++
>  include/linux/usb/phy.h  |    9 +++++++++
>  6 files changed, 127 insertions(+)
>  create mode 100644 drivers/usb/phy/of.c
>  create mode 100644 include/linux/usb/of.h
>
> diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
> index 9fa6327..e1be1e8 100644
> --- a/drivers/usb/phy/Makefile
> +++ b/drivers/usb/phy/Makefile
> @@ -5,6 +5,7 @@
>  ccflags-$(CONFIG_USB_DEBUG) := -DDEBUG
>  
>  obj-$(CONFIG_USB_OTG_UTILS)		+= phy.o
> +obj-$(CONFIG_OF)			+= of.o
>  obj-$(CONFIG_OMAP_USB2)			+= omap-usb2.o
>  obj-$(CONFIG_OMAP_USB3)			+= omap-usb3.o
>  obj-$(CONFIG_OMAP_CONTROL_USB)		+= omap-control-usb.o
> diff --git a/drivers/usb/phy/of.c b/drivers/usb/phy/of.c
> new file mode 100644
> index 0000000..e6f3b74
> --- /dev/null
> +++ b/drivers/usb/phy/of.c
> @@ -0,0 +1,47 @@
> +/*
> + * USB of helper code
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/usb/of.h>
> +#include <linux/usb/otg.h>
> +
> +static const char *usbphy_modes[] = {
> +	[USBPHY_INTERFACE_MODE_UNKNOWN]	= "",
> +	[USBPHY_INTERFACE_MODE_UTMI]	= "utmi",
> +	[USBPHY_INTERFACE_MODE_UTMIW]	= "utmi_wide",
> +	[USBPHY_INTERFACE_MODE_ULPI]	= "ulpi",
> +	[USBPHY_INTERFACE_MODE_SERIAL]	= "serial",
> +	[USBPHY_INTERFACE_MODE_HSIC]	= "hsic",
> +};
> +
> +/**
> + * of_usb_get_phy_mode - Get phy mode for given device_node
> + * @np:	Pointer to the given device_node
> + *
> + * The function gets phy interface string from property 'phy_type',
> + * and returns the correspondig enum usb_phy_interface
> + */
> +enum usb_phy_interface of_usb_get_phy_mode(struct device_node *np)
> +{
> +	const char *phy_type;
> +	int err, i;
> +
> +	err = of_property_read_string(np, "phy_type", &phy_type);
> +	if (err < 0)
> +		return USBPHY_INTERFACE_MODE_UNKNOWN;
> +
> +	for (i = 0; i < ARRAY_SIZE(usbphy_modes); i++)
> +		if (!strcmp(phy_type, usbphy_modes[i]))
> +			return i;
> +
> +	return USBPHY_INTERFACE_MODE_UNKNOWN;
> +}
> +EXPORT_SYMBOL_GPL(of_usb_get_phy_mode);
> diff --git a/drivers/usb/usb-common.c b/drivers/usb/usb-common.c
> index d29503e..ad4d87d 100644
> --- a/drivers/usb/usb-common.c
> +++ b/drivers/usb/usb-common.c
> @@ -14,6 +14,9 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/usb/ch9.h>
> +#include <linux/of.h>
> +#include <linux/usb/of.h>
> +#include <linux/usb/otg.h>
>  
>  const char *usb_speed_string(enum usb_device_speed speed)
>  {
> @@ -32,4 +35,37 @@ const char *usb_speed_string(enum usb_device_speed speed)
>  }
>  EXPORT_SYMBOL_GPL(usb_speed_string);
>  
> +#ifdef CONFIG_OF
> +static const char *usb_dr_modes[] = {
> +	[USB_DR_MODE_UNKNOWN]		= "",
> +	[USB_DR_MODE_HOST]		= "host",
> +	[USB_DR_MODE_PERIPHERAL]	= "peripheral",
> +	[USB_DR_MODE_OTG]		= "otg",
> +};

It turns out this is a problem, especially since this is generic usb
code: we have a chipidea controller (a patchset just arrived) that does
both host and peripheral, but not otg. And I'm told now that dwc3
controller can be synthesized like that too.

Summoning Felipe to the thread, this patch is largely his call anyway.

Regards,
--
Alex