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

[Kishon Vijay Abraham I <kishon@ti.com>]

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 <matt.porter@linaro.org>
> ---
>  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 <matt.porter@linaro.org>
> + *
> + * 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.
> +
> +#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.
> +
> +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..
> +};
> +
> +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 <matt.porter@linaro.org>");
> +MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
> +MODULE_LICENSE("GPL v2");
> 
Apart from those comments, this patch looks good.

Thanks
Kishon