Re: [PATCH 2/3] Broadcom USB DRD Phy driver for Northstar2

Kishon Vijay Abraham I
2017-01-16T09:24:04Z

Hi,

On Wednesday 30 November 2016 11:25 AM, Raviteja Garimella wrote:
> This is driver for USB DRD Phy used in Broadcom's Northstar2
> SoC. The phy can be configured to be in Device mode or Host
> mode based on the type of cable connected to the port. The
> driver registers to extcon framework to get appropriate
> connect events for Host/Device cables connect/disconnect
> states based on VBUS and ID interrupts.
>
> Signed-off-by: Raviteja Garimella <raviteja.garimella@broadcom.com>
> ---
> drivers/phy/Kconfig | 13 +
> drivers/phy/Makefile | 1 +
> drivers/phy/phy-bcm-ns2-usbdrd.c | 587 +++++++++++++++++++++++++++++++++++++++
> 3 files changed, 601 insertions(+)
> create mode 100644 drivers/phy/phy-bcm-ns2-usbdrd.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index fe00f91..b3b6a73 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -479,6 +479,19 @@ config PHY_CYGNUS_PCIE
> Enable this to support the Broadcom Cygnus PCIe PHY.
> If unsure, say N.
>
> +config PHY_NS2_USB_DRD
> + tristate "Broadcom Northstar2 USB DRD PHY support"
> + depends on OF && (ARCH_BCM_IPROC || COMPILE_TEST)
> + select GENERIC_PHY
> + select EXTCON
> + default ARCH_BCM_IPROC
> + help
> + Enable this to support the Broadcom Northstar2 USB DRD PHY.
> + This driver initializes the PHY in either HOST or DEVICE mode.
> + The host or device configuration is read from device tree.
> +
> + If unsure, say N.
> +
> source "drivers/phy/tegra/Kconfig"
>
> config PHY_NS2_PCIE
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index a534cf5..b733ba2 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -58,5 +58,6 @@ obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o
> obj-$(CONFIG_PHY_BRCM_SATA) += phy-brcm-sata.o
> obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o
> obj-$(CONFIG_PHY_CYGNUS_PCIE) += phy-bcm-cygnus-pcie.o
> +obj-$(CONFIG_PHY_NS2_USB_DRD) += phy-bcm-ns2-usbdrd.o
> obj-$(CONFIG_ARCH_TEGRA) += tegra/
> obj-$(CONFIG_PHY_NS2_PCIE) += phy-bcm-ns2-pcie.o
> diff --git a/drivers/phy/phy-bcm-ns2-usbdrd.c b/drivers/phy/phy-bcm-ns2-usbdrd.c
> new file mode 100644
> index 0000000..460040d
> --- /dev/null
> +++ b/drivers/phy/phy-bcm-ns2-usbdrd.c
> @@ -0,0 +1,587 @@
> +/*
> + * Copyright (C) 2016 Broadcom
> + *
> + * 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 version 2.
> + *
> + * This program is distributed "as is" WITHOUT ANY WARRANTY of any
> + * kind, whether express or implied; without even the implied warranty
> + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/extcon.h>
> +#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/workqueue.h>
> +
> +#define ICFG_DRD_AFE 0x0
> +#define ICFG_MISC_STAT 0x18
> +#define ICFG_DRD_P0CTL 0x1C
> +#define ICFG_STRAP_CTRL 0x20
> +#define ICFG_FSM_CTRL 0x24
> +
> +#define IDM_RST_BIT BIT(0)
> +#define AFE_CORERDY_VDDC BIT(18)
> +#define PHY_PLL_RESETB BIT(15)
> +#define PHY_RESETB BIT(14)
> +#define PHY_PLL_LOCK BIT(0)
> +
> +#define DRD_DEV_MODE BIT(20)
> +#define OHCI_OVRCUR_POL BIT(11)
> +#define ICFG_OFF_MODE BIT(6)
> +#define PLL_LOCK_RETRY 1000
> +
> +#define EVT_DEVICE 0
> +#define EVT_HOST 1
> +#define EVT_IDLE 2
> +
> +#define DRD_HOST_MODE (BIT(2) | BIT(3))
> +#define DRD_DEVICE_MODE (BIT(4) | BIT(5))
> +#define DRD_HOST_VAL 0x803
> +#define DRD_DEV_VAL 0x807
> +#define GPIO_DELAY 20
> +#define PHY_WQ_DELAY msecs_to_jiffies(600)
> +
> +struct ns2_phy_data;
> +struct ns2_phy_driver {
> + void __iomem *icfgdrd_regs;
> + void __iomem *idmdrd_rst_ctrl;
> + void __iomem *crmu_usb2_ctrl;
> + void __iomem *usb2h_strap_reg;
> + spinlock_t lock; /* spin lock for phy driver */
> + bool host_mode;
> + struct ns2_phy_data *data;
> + struct extcon_specific_cable_nb extcon_dev;
> + struct extcon_specific_cable_nb extcon_host;
> + struct notifier_block host_nb;
> + struct notifier_block dev_nb;
> + struct delayed_work conn_work;
> + struct extcon_dev *edev;
> + struct gpio_desc *vbus_gpiod;
> + struct gpio_desc *id_gpiod;
> + int id_irq;
> + int vbus_irq;
> + unsigned long debounce_jiffies;
> + struct delayed_work wq_extcon;
> +};
> +
> +struct ns2_phy_data {
> + struct ns2_phy_driver *driver;
> + struct phy *phy;
> + int new_state;
> + bool poweron;
> +};
> +
> +static const unsigned int usb_extcon_cable[] = {
> + EXTCON_USB,
> + EXTCON_USB_HOST,
> + EXTCON_NONE,
> +};
> +
> +static inline int pll_lock_stat(u32 usb_reg, int reg_mask,
> + struct ns2_phy_driver *driver)
> +{
> + int retry = PLL_LOCK_RETRY;
> + u32 val;
> +
> + do {
> + udelay(1);
> + val = readl(driver->icfgdrd_regs + usb_reg);
> + if (val & reg_mask)
> + return 0;
> + } while (--retry > 0);
> +
> + return -EBUSY;
> +}
> +
> +static int ns2_drd_phy_init(struct phy *phy)
> +{
> + struct ns2_phy_data *data = phy_get_drvdata(phy);
> + struct ns2_phy_driver *driver = data->driver;
> + unsigned long flags;
> + u32 val;
> +
> + spin_lock_irqsave(&driver->lock, flags);
> +
> + val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
> +
> + if (data->new_state == EVT_HOST) {
> + val &= ~DRD_DEVICE_MODE;
> + val |= DRD_HOST_MODE;
> + } else {
> + val &= ~DRD_HOST_MODE;
> + val |= DRD_DEVICE_MODE;
> + }
> + writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
> +
> + spin_unlock_irqrestore(&driver->lock, flags);
> + return 0;
> +}
> +
> +static int ns2_drd_phy_shutdown(struct phy *phy)
> +{
> + struct ns2_phy_data *data = phy_get_drvdata(phy);
> + struct ns2_phy_driver *driver = data->driver;
> + unsigned long flags;
> + u32 val;
> +
> + spin_lock_irqsave(&driver->lock, flags);
> + if (!data->poweron)
> + goto exit;
> +
> + val = readl(driver->crmu_usb2_ctrl);
> + val &= ~AFE_CORERDY_VDDC;
> + writel(val, driver->crmu_usb2_ctrl);
> +
> + driver->host_mode = 0;
> + val = readl(driver->crmu_usb2_ctrl);
> + val &= ~DRD_DEV_MODE;
> + writel(val, driver->crmu_usb2_ctrl);
> +
> + /* Disable Host and Device Mode */
> + val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
> + val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE | ICFG_OFF_MODE);
> + writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
> +
> + data->poweron = 0;
> +exit:
> + spin_unlock_irqrestore(&driver->lock, flags);
> + return 0;
> +}
> +
> +static int ns2_drd_phy_poweron(struct phy *phy)
> +{
> + struct ns2_phy_data *data = phy_get_drvdata(phy);
> + struct ns2_phy_driver *driver = data->driver;
> + u32 extcon_event = data->new_state;
> + unsigned long flags;
> + int ret;
> + u32 val;
> +
> + spin_lock_irqsave(&driver->lock, flags);
> + if (extcon_event == EVT_DEVICE) {
> + if (data->poweron)
> + goto exit;
> +
> + writel(DRD_DEV_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
> +
> + val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
> + val &= ~(DRD_HOST_MODE | ICFG_OFF_MODE);
> + val |= DRD_DEVICE_MODE;
> + writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
> +
> + val = readl(driver->idmdrd_rst_ctrl);
> + val &= ~IDM_RST_BIT;
> + writel(val, driver->idmdrd_rst_ctrl);
> +
> + val = readl(driver->crmu_usb2_ctrl);
> + val |= (AFE_CORERDY_VDDC | DRD_DEV_MODE);
> + writel(val, driver->crmu_usb2_ctrl);
> +
> + /* Bring PHY and PHY_PLL out of Reset */
> + val = readl(driver->crmu_usb2_ctrl);
> + val |= (PHY_PLL_RESETB | PHY_RESETB);
> + writel(val, driver->crmu_usb2_ctrl);
> +
> + ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
> + if (ret < 0) {
> + dev_err(&phy->dev, "Phy PLL lock failed\n");
> + goto err_shutdown;
> + }
> + } else {
> + if (data->poweron && driver->host_mode)
> + goto exit;
> +
> + writel(DRD_HOST_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
> +
> + val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
> + val &= ~(DRD_DEVICE_MODE | ICFG_OFF_MODE);
> + val |= DRD_HOST_MODE;
> + writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
> +
> + val = readl(driver->crmu_usb2_ctrl);
> + val |= AFE_CORERDY_VDDC;
> + writel(val, driver->crmu_usb2_ctrl);
> +
> + ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
> + if (ret < 0) {
> + dev_err(&phy->dev, "Phy PLL lock failed\n");
> + goto err_shutdown;
> + }
> +
> + val = readl(driver->idmdrd_rst_ctrl);
> + val &= ~IDM_RST_BIT;
> + writel(val, driver->idmdrd_rst_ctrl);
> +
> + /* port over current Polarity */
> + val = readl(driver->usb2h_strap_reg);
> + val |= OHCI_OVRCUR_POL;
> + writel(val, driver->usb2h_strap_reg);
> +
> + driver->host_mode = 1;
> + }
> +
> + data->poweron = 1;
> +exit:
> + spin_unlock_irqrestore(&driver->lock, flags);
> + return 0;
> +
> +err_shutdown:
> + data->poweron = 1;
> + spin_unlock_irqrestore(&driver->lock, flags);
> + ns2_drd_phy_shutdown(phy);
> + return ret;
> +}
> +
> +static void connect_work(struct work_struct *work)
> +{
> + struct ns2_phy_driver *driver;
> + struct ns2_phy_data *data;
> + u32 extcon_event;
> +
> + driver = container_of(to_delayed_work(work),
> + struct ns2_phy_driver, conn_work);
> + data = driver->data;
> + extcon_event = data->new_state;
> +
> + if (extcon_event == EVT_DEVICE || extcon_event == EVT_HOST) {
> + ns2_drd_phy_init(data->phy);
> + ns2_drd_phy_poweron(data->phy);
> + } else if (extcon_event == EVT_IDLE) {
> + ns2_drd_phy_shutdown(data->phy);
> + }
> +}
> +
> +static int drd_device_notify(struct notifier_block *self,
> + unsigned long event, void *ptr)
> +{
> + struct ns2_phy_driver *driver = container_of(self,
> + struct ns2_phy_driver, dev_nb);
> +
> + if (event) {
> + pr_debug("Device connected\n");
> + driver->data->new_state = EVT_DEVICE;
> + schedule_delayed_work(&driver->conn_work, 0);
> + } else {
> + pr_debug("Device disconnected\n");
> + driver->data->new_state = EVT_IDLE;
> + schedule_delayed_work(&driver->conn_work, PHY_WQ_DELAY);
> + }
> +
> + return NOTIFY_DONE;
> +}
> +
> +static int drd_host_notify(struct notifier_block *self,
> + unsigned long event, void *ptr)
> +{
> + struct ns2_phy_driver *driver = container_of(self,
> + struct ns2_phy_driver, host_nb);
> +
> + if (event) {
> + pr_debug("Host connected\n");
> + driver->data->new_state = EVT_HOST;
> + schedule_delayed_work(&driver->conn_work, 0);
> + } else {
> + pr_debug("Host disconnected\n");
> + driver->data->new_state = EVT_IDLE;
> + schedule_delayed_work(&driver->conn_work, PHY_WQ_DELAY);
> + }
> +
> + return NOTIFY_DONE;
> +}
> +
> +static void extcon_work(struct work_struct *work)
> +{
> + struct ns2_phy_driver *driver;
> + int vbus;
> + int id;
> +
> + driver = container_of(to_delayed_work(work),
> + struct ns2_phy_driver, wq_extcon);
> +
> + id = gpiod_get_value_cansleep(driver->id_gpiod);
> + vbus = gpiod_get_value_cansleep(driver->vbus_gpiod);
> +
> + if (!id && vbus) {
> + extcon_set_cable_state_(driver->edev, EXTCON_USB_HOST, true);
> + } else if (id && !vbus) {
> + extcon_set_cable_state_(driver->edev, EXTCON_USB_HOST, false);
> + extcon_set_cable_state_(driver->edev, EXTCON_USB, false);
> + } else if (id && vbus) {
> + extcon_set_cable_state_(driver->edev, EXTCON_USB, true);
> + }
> +}
> +
> +static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
> +{
> + struct ns2_phy_driver *driver = dev_id;
> +
> + queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
> + driver->debounce_jiffies);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int register_extcon_notifier(struct ns2_phy_driver *phy_driver,
> + struct device *dev)
> +{
> + struct extcon_dev *edev;
> + int ret;
> +
> + phy_driver->host_nb.notifier_call = drd_host_notify;
> + phy_driver->dev_nb.notifier_call = drd_device_notify;
> +
> + edev = phy_driver->edev;
> +
> + /* Register for device change notification */
> + ret = extcon_register_notifier(edev, EXTCON_USB,
> + &phy_driver->dev_nb);
> + if (ret < 0) {
> + dev_err(dev, "can't register extcon_dev for %s\n", edev->name);
> + return ret;
> + }
> +
> + /* Register for host change notification */
> + ret = extcon_register_notifier(edev, EXTCON_USB_HOST,
> + &phy_driver->host_nb);
> + if (ret < 0) {
> + dev_err(dev, "can't register extcon_dev for %s\n", edev->name);
> + goto err_dev;
> + }
> +
> + /* Check the device cable connect state */
> + ret = extcon_get_cable_state_(edev, EXTCON_USB);
> + if (ret < 0) {
> + dev_err(dev, "can't get extcon_dev state for %s\n", edev->name);
> + goto err_host;
> + } else if (ret) {
> + phy_driver->data->new_state = EVT_DEVICE;
> + }
> +
> + /* Check the host cable connect state */
> + ret = extcon_get_cable_state_(edev, EXTCON_USB_HOST);
> + if (ret < 0) {
> + dev_err(dev, "can't get extcon_dev state for %s\n", edev->name);
> + goto err_host;
> + } else if (ret) {
> + phy_driver->data->new_state = EVT_HOST;
> + }
> +
> + return 0;
> +
> +err_host:
> + ret = extcon_unregister_notifier(edev, EXTCON_USB_HOST,
> + &phy_driver->host_nb);
> +err_dev:
> + ret = extcon_unregister_notifier(edev, EXTCON_USB,
> + &phy_driver->dev_nb);
> + return ret;
> +}
> +
> +static struct phy_ops ops = {
> + .init = ns2_drd_phy_init,

Is this really being used by any controller driver? Can you point me to the
controller driver that is using this driver?

> + .power_on = ns2_drd_phy_poweron,
> + .power_off = ns2_drd_phy_shutdown,

missing .owner.

Thanks
Kishon