[v2,8/9] phy: add Broadcom Kona USB2 PHY driver

Message ID 1383335158-19730-9-git-send-email-matt.porter@linaro.org
State Superseded
Headers show

Commit Message

Matt Porter Nov. 1, 2013, 7:45 p.m.
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            |   2 +
 drivers/phy/phy-bcm-kona-usb2.c | 161 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 169 insertions(+)
 create mode 100644 drivers/phy/phy-bcm-kona-usb2.c

Comments

Kishon Vijay Abraham I Nov. 4, 2013, 6:27 a.m. | #1
Hi,

On Saturday 02 November 2013 01:15 AM, 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            |   2 +
>   drivers/phy/phy-bcm-kona-usb2.c | 161 ++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 169 insertions(+)
>   create mode 100644 drivers/phy/phy-bcm-kona-usb2.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 349bef2..cedada5 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -15,4 +15,10 @@ config GENERIC_PHY
>   	  phy users can obtain reference to the PHY. All the users of this
>   	  framework should select this config.
>
> +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 9e9560f..ce83a14 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -3,3 +3,5 @@
>   #
>
>   obj-$(CONFIG_GENERIC_PHY)	+= phy-core.o
> +
> +obj-$(CONFIG_BCM_KONA_USB2_PHY)	+= phy-bcm-kona-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..1beea7f
> --- /dev/null
> +++ b/drivers/phy/phy-bcm-kona-usb2.c
> @@ -0,0 +1,161 @@
> +/*
> + * 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>
> +
> +#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_SOFT_RESET	(1 << 1)
> +#define P1CTL_NON_DRIVING	(1 << 0)
> +
> +struct bcm_kona_usb_phy_regs {
> +	u32 ctrl;
> +	u32 cfg;
> +	u32 p1ctl;
> +	u32 status;
> +	u32 bc_cfg;
> +	u32 tp_in;
> +	u32 tp_out;
> +	u32 phy_ctrl;
> +	u32 usbreg;
> +	u32 usbproben;
> +};

I would prefer to have constant macros for register offset unless you 
have a good reason to do otherwise.
> +
> +struct bcm_kona_usb {
> +	struct bcm_kona_usb_phy_regs *regs;
> +};
> +
> +static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
> +{
> +	u32 val;
> +
> +	val = readl(&phy->regs->ctrl);
> +	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;
> +		writel(val, &phy->regs->ctrl);
> +
> +		/* 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);

Is soft reset needed for every power-on? Shouldn't soft reset be present 
in phy_init?

Cheers
Kishon
Matt Porter Nov. 25, 2013, 2:16 p.m. | #2
On Mon, Nov 04, 2013 at 11:57:10AM +0530, Kishon Vijay Abraham I wrote:
> Hi,
> 
> On Saturday 02 November 2013 01:15 AM, 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            |   2 +
> >  drivers/phy/phy-bcm-kona-usb2.c | 161 ++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 169 insertions(+)
> >  create mode 100644 drivers/phy/phy-bcm-kona-usb2.c
> >
> >diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> >index 349bef2..cedada5 100644
> >--- a/drivers/phy/Kconfig
> >+++ b/drivers/phy/Kconfig
> >@@ -15,4 +15,10 @@ config GENERIC_PHY
> >  	  phy users can obtain reference to the PHY. All the users of this
> >  	  framework should select this config.
> >
> >+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 9e9560f..ce83a14 100644
> >--- a/drivers/phy/Makefile
> >+++ b/drivers/phy/Makefile
> >@@ -3,3 +3,5 @@
> >  #
> >
> >  obj-$(CONFIG_GENERIC_PHY)	+= phy-core.o
> >+
> >+obj-$(CONFIG_BCM_KONA_USB2_PHY)	+= phy-bcm-kona-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..1beea7f
> >--- /dev/null
> >+++ b/drivers/phy/phy-bcm-kona-usb2.c
> >@@ -0,0 +1,161 @@
> >+/*
> >+ * 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>
> >+
> >+#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_SOFT_RESET	(1 << 1)
> >+#define P1CTL_NON_DRIVING	(1 << 0)
> >+
> >+struct bcm_kona_usb_phy_regs {
> >+	u32 ctrl;
> >+	u32 cfg;
> >+	u32 p1ctl;
> >+	u32 status;
> >+	u32 bc_cfg;
> >+	u32 tp_in;
> >+	u32 tp_out;
> >+	u32 phy_ctrl;
> >+	u32 usbreg;
> >+	u32 usbproben;
> >+};
> 
> I would prefer to have constant macros for register offset unless
> you have a good reason to do otherwise.

I'll switch to constant macros in v3. It's just my personal preference
for style.

> >+
> >+struct bcm_kona_usb {
> >+	struct bcm_kona_usb_phy_regs *regs;
> >+};
> >+
> >+static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
> >+{
> >+	u32 val;
> >+
> >+	val = readl(&phy->regs->ctrl);
> >+	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;
> >+		writel(val, &phy->regs->ctrl);
> >+
> >+		/* 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);
> 
> Is soft reset needed for every power-on? Shouldn't soft reset be
> present in phy_init?

Not needed for every power-on. Yes, I've addressed that now for v3,
thanks.

-Matt

Patch

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 349bef2..cedada5 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -15,4 +15,10 @@  config GENERIC_PHY
 	  phy users can obtain reference to the PHY. All the users of this
 	  framework should select this config.
 
+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 9e9560f..ce83a14 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -3,3 +3,5 @@ 
 #
 
 obj-$(CONFIG_GENERIC_PHY)	+= phy-core.o
+
+obj-$(CONFIG_BCM_KONA_USB2_PHY)	+= phy-bcm-kona-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..1beea7f
--- /dev/null
+++ b/drivers/phy/phy-bcm-kona-usb2.c
@@ -0,0 +1,161 @@ 
+/*
+ * 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>
+
+#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_SOFT_RESET	(1 << 1)
+#define P1CTL_NON_DRIVING	(1 << 0)
+
+struct bcm_kona_usb_phy_regs {
+	u32 ctrl;
+	u32 cfg;
+	u32 p1ctl;
+	u32 status;
+	u32 bc_cfg;
+	u32 tp_in;
+	u32 tp_out;
+	u32 phy_ctrl;
+	u32 usbreg;
+	u32 usbproben;
+};
+
+struct bcm_kona_usb {
+	struct bcm_kona_usb_phy_regs *regs;
+};
+
+static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
+{
+	u32 val;
+
+	val = readl(&phy->regs->ctrl);
+	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;
+		writel(val, &phy->regs->ctrl);
+
+		/* 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);
+	} else {
+		val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
+		writel(val, &phy->regs->ctrl);
+	}
+}
+
+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 = {
+	.power_on	= bcm_kona_usb_phy_power_on,
+	.power_off	= bcm_kona_usb_phy_power_off,
+	.owner = THIS_MODULE,
+};
+
+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");
+MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
+MODULE_LICENSE("GPL v2");