[PATCH 5/8] MXS: Add USB PHY driver

[s.hauer@pengutronix.de (Sascha Hauer)]

On Tue, Apr 17, 2012 at 12:15:48PM +0200, Marek Vasut wrote:
> Add driver that controls the built-in USB PHY in the i.MX233/i.MX28. This
> enables the PHY upon powerup and shuts it down on shutdown.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Chen Peter-B29397 <B29397@freescale.com>
> Cc: Detlev Zundel <dzu@denx.de>
> Cc: Fabio Estevam <festevam@gmail.com>
> Cc: Li Frank-B20596 <B20596@freescale.com>
> Cc: Lin Tony-B19295 <B19295@freescale.com>
> Cc: Linux USB <linux-usb@vger.kernel.org>
> Cc: Sascha Hauer <s.hauer@pengutronix.de>
> Cc: Shawn Guo <shawn.guo@freescale.com>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: Stefano Babic <sbabic@denx.de>
> Cc: Subodh Nijsure <snijsure@grid-net.com>
> Cc: Tony Lin <tony.lin@freescale.com>
> Cc: Wolfgang Denk <wd@denx.de>
> ---
>  drivers/usb/otg/Kconfig   |    9 ++
>  drivers/usb/otg/Makefile  |    1 +
>  drivers/usb/otg/mxs-phy.c |  256 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 266 insertions(+)
>  create mode 100644 drivers/usb/otg/mxs-phy.c
> 
> diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
> index 5c87db0..8689081 100644
> --- a/drivers/usb/otg/Kconfig
> +++ b/drivers/usb/otg/Kconfig
> @@ -116,6 +116,15 @@ config FSL_USB2_OTG
>  	help
>  	  Enable this to support Freescale USB OTG transceiver.
>  
> +config USB_MXS_PHY
> +	tristate "Freescale i.MX28 USB PHY support"
> +	select USB_OTG_UTILS
> +	help
> +	  Say Y here if you want to build Freescale i.MX28 USB PHY
> +	  driver in kernel.
> +
> +	  To compile this driver as a module, choose M here.
> +
>  config USB_MV_OTG
>  	tristate "Marvell USB OTG support"
>  	depends on USB_EHCI_MV && USB_MV_UDC && USB_SUSPEND
> diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
> index 41aa509..a844b8d 100644
> --- a/drivers/usb/otg/Makefile
> +++ b/drivers/usb/otg/Makefile
> @@ -20,4 +20,5 @@ obj-$(CONFIG_USB_MSM_OTG)	+= msm_otg.o
>  obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o
>  fsl_usb2_otg-objs		:= fsl_otg.o otg_fsm.o
>  obj-$(CONFIG_FSL_USB2_OTG)	+= fsl_usb2_otg.o
> +obj-$(CONFIG_USB_MXS_PHY)	+= mxs-phy.o
>  obj-$(CONFIG_USB_MV_OTG)	+= mv_otg.o
> diff --git a/drivers/usb/otg/mxs-phy.c b/drivers/usb/otg/mxs-phy.c
> new file mode 100644
> index 0000000..9963aa8
> --- /dev/null
> +++ b/drivers/usb/otg/mxs-phy.c
> @@ -0,0 +1,256 @@
> +/*
> + * drivers/usb/otg/mxs-phy.c
> + *
> + * Freescale i.MX28 USB PHY driver.
> + *
> + * Copyright (C) 2012 Marek Vasut <marex@denx.de>
> + * on behalf of DENX Software Engineering GmbH
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/usb/otg.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +
> +#include <mach/common.h>
> +#include <mach/hardware.h>
> +#include <mach/devices-common.h>
> +#include <mach/mx28.h>
> +
> +#define HW_USBPHY_PWD				0x00
> +
> +#define HW_USBPHY_CTRL				0x30
> +#define HW_USBPHY_CTRL_SET			0x34
> +#define HW_USBPHY_CTRL_CLR			0x38
> +#define HW_USBPHY_CTRL_TOG			0x3c
> +
> +#define BM_USBPHY_CTRL_SFTRST			(1 << 31)
> +#define BM_USBPHY_CTRL_CLKGATE			(1 << 30)
> +#define BM_USBPHY_CTRL_ENUTMILEVEL3		(1 << 15)
> +#define BM_USBPHY_CTRL_ENUTMILEVEL2		(1 << 14)
> +#define BM_USBPHY_CTRL_ENHOSTDISCONDETECT	(1 << 1)
> +
> +struct mxs_phy {
> +	struct usb_phy	phy;
> +	struct device	*dev;
> +	struct clk	*clk;
> +	struct resource	*res;
> +	void __iomem	*reg;
> +};
> +
> +static int phy_init(struct usb_phy *x)
> +{
> +	struct mxs_phy *phy = container_of(x, struct mxs_phy, phy);
> +	uint32_t val;
> +
> +	/* Enable clock to the PHY. */
> +	clk_enable(phy->clk);
> +
> +	/* Reset the PHY block. */
> +	mxs_reset_block(phy->reg + HW_USBPHY_CTRL);
> +
> +	/* Power up the PHY. */
> +	writel(0, phy->reg + HW_USBPHY_PWD);
> +
> +	/* Enable FS/LS compatibility and HS disconnection detector. */
> +	val = BM_USBPHY_CTRL_ENUTMILEVEL2 | BM_USBPHY_CTRL_ENUTMILEVEL3 |
> +		BM_USBPHY_CTRL_ENHOSTDISCONDETECT;
> +	writel(val, phy->reg + HW_USBPHY_CTRL_SET);
> +
> +	return 0;
> +}
> +
> +static void phy_shutdown(struct usb_phy *x)
> +{
> +	struct mxs_phy *phy = container_of(x, struct mxs_phy, phy);
> +
> +	/* Gate off the PHY. */
> +	writel(BM_USBPHY_CTRL_CLKGATE, phy->reg + HW_USBPHY_CTRL_SET);
> +
> +	/* Disable clock to the PHY. */
> +	clk_disable(phy->clk);
> +}
> +
> +static int phy_set_vbus(struct usb_otg *otg, bool enabled)
> +{
> +	struct usb_phy *x = otg->phy;
> +	struct mxs_phy *phy = container_of(x, struct mxs_phy, phy);
> +
> +	if (enabled)
> +		writel(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
> +			phy->reg + HW_USBPHY_CTRL_CLR);
> +	else
> +		writel(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
> +			phy->reg + HW_USBPHY_CTRL_SET);
> +
> +	return 0;
> +}
> +
> +static int __devinit mxs_phy_probe(struct platform_device *pdev)
> +{
> +	struct mxs_phy *phy;
> +	struct resource *res;
> +	int ret;
> +
> +	/* Allocate PHY driver's private date. */
> +	phy = kzalloc(sizeof *phy, GFP_KERNEL);
> +	if (!phy) {
> +		ret = -ENOMEM;
> +		goto err_alloc_phy;
> +	}

Use devm_* functions?


> +
> +	/* Enable the PHY clock. */
> +	clk_prepare_enable(phy->clk);

The clock is enabled in probe and then again in phy_init. Once is
enough.

Sascha

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