Subject: [PATCH v3 8/9] phy: add Broadcom Kona USB2 PHY driver

From: [email-masked] (Matt Porter)
Date: Wed, 27 Nov 2013 12:21:37 -0500

On Wed, Nov 27, 2013 at 02:21:52PM +0530, Kishon Vijay Abraham I wrote:
> Hi,
> 
> On Monday 25 November 2013 11:46 PM, Matt Porter wrote:
> > Add a driver for the internal Broadcom Kona USB 2.0 PHY found
> > on the BCM281xx family of SoCs.
> > 
> > Signed-off-by: Matt Porter <[email-masked]>
> > ---
> >  drivers/phy/Kconfig             |   6 ++
> >  drivers/phy/Makefile            |   1 +
> >  drivers/phy/phy-bcm-kona-usb2.c | 158 ++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 165 insertions(+)
> >  create mode 100644 drivers/phy/phy-bcm-kona-usb2.c
> > 
> > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> > index a344f3d..2e87fa8 100644
> > --- a/drivers/phy/Kconfig
> > +++ b/drivers/phy/Kconfig
> > @@ -51,4 +51,10 @@ config PHY_EXYNOS_DP_VIDEO
> >  	help
> >  	  Support for Display Port PHY found on Samsung EXYNOS SoCs.
> >  
> > +config BCM_KONA_USB2_PHY
> > +	tristate "Broadcom Kona USB2 PHY Driver"
> > +	depends on GENERIC_PHY
> > +	help
> > +	  Enable this to support the Broadcom Kona USB 2.0 PHY.
> > +
> >  endmenu
> > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> > index d0caae9..c447f1a 100644
> > --- a/drivers/phy/Makefile
> > +++ b/drivers/phy/Makefile
> > @@ -3,6 +3,7 @@
> >  #
> >  
> >  obj-$(CONFIG_GENERIC_PHY)		+= phy-core.o
> > +obj-$(CONFIG_BCM_KONA_USB2_PHY)		+= phy-bcm-kona-usb2.o
> >  obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO)	+= phy-exynos-dp-video.o
> >  obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO)	+= phy-exynos-mipi-video.o
> >  obj-$(CONFIG_OMAP_USB2)			+= phy-omap-usb2.o
> > diff --git a/drivers/phy/phy-bcm-kona-usb2.c b/drivers/phy/phy-bcm-kona-usb2.c
> > new file mode 100644
> > index 0000000..2c54fb8
> > --- /dev/null
> > +++ b/drivers/phy/phy-bcm-kona-usb2.c
> > @@ -0,0 +1,158 @@
> > +/*
> > + * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
> > + *
> > + * Copyright (C) 2013 Linaro Limited
> > + * Matt Porter <[email-masked]>
> > + *
> > + * This software is licensed under the terms of the GNU General Public
> > + * License version 2, as published by the Free Software Foundation, and
> > + * may be copied, distributed, and modified under those terms.
> > + *
> > + * 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.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/delay.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/err.h>
> > +#include <linux/io.h>
> > +#include <linux/clk.h>
> > +#include <linux/phy/phy.h>
> 
> arrange the headers in alphabetical order so that it's easy while adding new
> headers. Just my preference.

yeah, same here. just development creep that I will address.

> > +
> > +#define OTGCTL			(0)
> > +#define OTGCTL_OTGSTAT2		(1 << 31)
> > +#define OTGCTL_OTGSTAT1		(1 << 30)
> > +#define OTGCTL_PRST_N_SW	(1 << 11)
> > +#define OTGCTL_HRESET_N		(1 << 10)
> > +#define OTGCTL_UTMI_LINE_STATE1	(1 << 9)
> > +#define OTGCTL_UTMI_LINE_STATE0	(1 << 8)
> > +
> > +#define P1CTL			(8)
> > +#define P1CTL_SOFT_RESET	(1 << 1)
> > +#define P1CTL_NON_DRIVING	(1 << 0)
> 
> you can use BIT() instead.

will do

> > +
> > +struct bcm_kona_usb {
> > +	void __iomem *regs;
> > +};
> > +
> > +static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
> > +{
> > +	u32 val;
> > +
> > +	val = readl(phy->regs + OTGCTL);
> > +	if (on) {
> > +		/* Configure and power PHY */
> > +		val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
> > +			 OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
> > +		val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
> > +	} else {
> > +		val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
> > +	}
> > +	writel(val, phy->regs + OTGCTL);
> > +}
> > +
> > +static int bcm_kona_usb_phy_init(struct phy *gphy)
> > +{
> > +	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
> > +	u32 val;
> > +
> > +	/* Soft reset PHY */
> > +	val = readl(phy->regs + P1CTL);
> > +	val &= ~P1CTL_NON_DRIVING;
> > +	val |= P1CTL_SOFT_RESET;
> > +	writel(val, phy->regs + P1CTL);
> > +	writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
> > +	/* Reset needs to be asserted for 2ms */
> > +	mdelay(2);
> > +	writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
> > +
> > +	return 0;
> > +}
> > +
> > +static int bcm_kona_usb_phy_power_on(struct phy *gphy)
> > +{
> > +	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
> > +
> > +	bcm_kona_usb_phy_power(phy, 1);
> > +
> > +	return 0;
> > +}
> > +
> > +static int bcm_kona_usb_phy_power_off(struct phy *gphy)
> > +{
> > +	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
> > +
> > +	bcm_kona_usb_phy_power(phy, 0);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct phy_ops ops = {
> > +	.init		= bcm_kona_usb_phy_init,
> > +	.power_on	= bcm_kona_usb_phy_power_on,
> > +	.power_off	= bcm_kona_usb_phy_power_off,
> > +	.owner = THIS_MODULE,
> 
> owner is aligned differently..

ok

> > +};
> > +
> > +static int bcm_kona_usb2_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	struct bcm_kona_usb *phy;
> > +	struct resource *res;
> > +	struct phy *gphy;
> > +	struct phy_provider *phy_provider;
> > +
> > +	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
> > +	if (!phy)
> > +		return -ENOMEM;
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	phy->regs = devm_ioremap_resource(&pdev->dev, res);
> > +	if (IS_ERR(phy->regs))
> > +		return PTR_ERR(phy->regs);
> > +
> > +	platform_set_drvdata(pdev, phy);
> > +
> > +	phy_provider = devm_of_phy_provider_register(dev,
> > +			of_phy_simple_xlate);
> > +	if (IS_ERR(phy_provider))
> > +		return PTR_ERR(phy_provider);
> > +
> > +	gphy = devm_phy_create(dev, &ops, NULL);
> > +	if (IS_ERR(gphy))
> > +		return PTR_ERR(gphy);
> > +
> > +	/* The Kona PHY supports an 8-bit wide UTMI interface */
> > +	phy_set_bus_width(gphy, 8);
> > +
> > +	phy_set_drvdata(gphy, phy);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
> > +	{ .compatible = "brcm,kona-usb2-phy" },
> > +	{ /* sentinel */ }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
> > +
> > +static struct platform_driver bcm_kona_usb2_driver = {
> > +	.probe		= bcm_kona_usb2_probe,
> > +	.driver		= {
> > +		.name	= "bcm-kona-usb2",
> > +		.owner	= THIS_MODULE,
> > +		.of_match_table = bcm_kona_usb2_dt_ids,
> > +	},
> > +};
> > +
> > +module_platform_driver(bcm_kona_usb2_driver);
> > +
> > +MODULE_ALIAS("platform:bcm-kona-usb2");
> > +MODULE_AUTHOR("Matt Porter <[email-masked]>");
> > +MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
> > +MODULE_LICENSE("GPL v2");
> > 
> Apart from those comments, this patch looks good.

Ok, thanks much for all the reviews.

-Matt