[PATCH v7 2/3] phy:phy-bcm-ns2-usbdrd:Broadcom USB DRD Phy driver for Northstar2

Raviteja Garimella raviteja.garimella at broadcom.com
Thu Jun 8 03:26:56 PDT 2017


Hi Kishon,

On Wed, Jun 7, 2017 at 7:08 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
> Hi,
>
> On Friday 02 June 2017 06:30 PM, 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 at broadcom.com>
>> ---
>>  drivers/phy/Kconfig              |  13 ++
>>  drivers/phy/Makefile             |   1 +
>>  drivers/phy/phy-bcm-ns2-usbdrd.c | 450 +++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 464 insertions(+)
>>  create mode 100644 drivers/phy/phy-bcm-ns2-usbdrd.c
>>
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index afaf7b6..8028da7 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -507,6 +507,19 @@ 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 f8047b4..e5fbb0e 100644
>> --- a/drivers/phy/Makefile
>> +++ b/drivers/phy/Makefile
>> @@ -61,6 +61,7 @@ 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-$(CONFIG_PHY_NS2_PCIE)           += phy-bcm-ns2-pcie.o
>>  obj-$(CONFIG_PHY_MESON8B_USB2)               += phy-meson8b-usb2.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..4a1e181
>> --- /dev/null
>> +++ b/drivers/phy/phy-bcm-ns2-usbdrd.c
>> @@ -0,0 +1,450 @@
>> +/*
>> + * Copyright (C) 2017 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 ICFG_DEV_BIT         BIT(2)
>> +#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 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
>> +
>> +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;
>> +     struct ns2_phy_data *data;
>> +     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;
>> +};
>> +
>> +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;
>> +     u32 val;
>> +
>> +     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);
>> +
>> +     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;
>> +     u32 val;
>> +
>> +     val = readl(driver->crmu_usb2_ctrl);
>> +     val &= ~AFE_CORERDY_VDDC;
>> +     writel(val, driver->crmu_usb2_ctrl);
>> +
>> +     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);
>> +
>> +     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;
>> +     int ret;
>> +     u32 val;
>> +
>> +     if (extcon_event == EVT_DEVICE) {
>> +             writel(DRD_DEV_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +
>> +             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");
>> +                     return ret;
>> +             }
>> +     } else {
>> +             writel(DRD_HOST_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +
>> +             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");
>> +                     return ret;
>> +             }
>> +
>> +             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);
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static void connect_change(struct ns2_phy_driver *driver)
>> +{
>> +     u32 extcon_event;
>> +     u32 val;
>> +
>> +     extcon_event = driver->data->new_state;
>> +     val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
>> +
>> +     switch (extcon_event) {
>> +     case EVT_DEVICE:
>> +             val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
>> +             writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
>> +
>> +             val = (val & ~DRD_HOST_MODE) | DRD_DEVICE_MODE;
>> +             writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
>> +
>> +             val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +             val |= ICFG_DEV_BIT;
>> +             writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +             break;
>> +
>> +     case EVT_HOST:
>> +             val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
>> +             writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
>> +
>> +             val = (val & ~DRD_DEVICE_MODE) | DRD_HOST_MODE;
>> +             writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
>> +
>> +             val = readl(driver->usb2h_strap_reg);
>> +             val |= OHCI_OVRCUR_POL;
>> +             writel(val, driver->usb2h_strap_reg);
>> +
>> +             val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +             val &= ~ICFG_DEV_BIT;
>> +             writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
>> +             break;
>> +
>> +     default:
>> +             pr_err("Invalid extcon event\n");
>> +             break;
>> +     }
>> +}
>> +
>> +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) { /* Host connected */
>> +             extcon_set_cable_state_(driver->edev, EXTCON_USB_HOST, true);
>> +             pr_debug("Host cable connected\n");
>> +             driver->data->new_state = EVT_HOST;
>> +             connect_change(driver);
>> +     } else if (id && !vbus) { /* Disconnected */
>> +             extcon_set_cable_state_(driver->edev, EXTCON_USB_HOST, false);
>> +             extcon_set_cable_state_(driver->edev, EXTCON_USB, false);
>> +             pr_debug("Cable disconnected\n");
>> +     } else if (id && vbus) { /* Device connected */
>> +             extcon_set_cable_state_(driver->edev, EXTCON_USB, true);
>> +             pr_debug("Device cable connected\n");
>> +             driver->data->new_state = EVT_DEVICE;
>> +             connect_change(driver);
>> +     }
>> +}
>> +
>> +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);
>
> The gpio_irq_handler is already executing in threaded context. Why do you again
> want to schedule a work?

Without that debounce delay, we may see intermittent connect/disconnect issues.
We can tune the delay as well now.
Using threaded irq is not so much required, I can change that in probe routine.

>> +
>> +     return IRQ_HANDLED;
>> +}
>> +
>> +static struct phy_ops ops = {
>> +     .init           = ns2_drd_phy_init,
>> +     .power_on       = ns2_drd_phy_poweron,
>> +     .power_off      = ns2_drd_phy_shutdown,
>
> rename it to ns2_drd_phy_poweroff?

Ok.

>> +     .owner          = THIS_MODULE,
>> +};
>> +
>> +static const struct of_device_id ns2_drd_phy_dt_ids[] = {
>> +     { .compatible = "brcm,ns2-drd-phy", },
>> +     { }
>> +};
>> +
>> +static int ns2_drd_phy_probe(struct platform_device *pdev)
>> +{
>> +     struct phy_provider *phy_provider;
>> +     struct device *dev = &pdev->dev;
>> +     struct ns2_phy_driver *driver;
>> +     struct ns2_phy_data *data;
>> +     struct resource *res;
>> +     int ret;
>> +     u32 val;
>> +
>> +     driver = devm_kzalloc(dev, sizeof(struct ns2_phy_driver),
>> +                           GFP_KERNEL);
>> +     if (!driver)
>> +             return -ENOMEM;
>> +
>> +     driver->data = devm_kzalloc(dev, sizeof(struct ns2_phy_data),
>> +                               GFP_KERNEL);
>> +     if (!driver->data)
>> +             return -ENOMEM;
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "icfg");
>> +     driver->icfgdrd_regs = devm_ioremap_resource(dev, res);
>> +     if (IS_ERR(driver->icfgdrd_regs))
>> +             return PTR_ERR(driver->icfgdrd_regs);
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rst-ctrl");
>> +     driver->idmdrd_rst_ctrl = devm_ioremap_resource(dev, res);
>> +     if (IS_ERR(driver->idmdrd_rst_ctrl))
>> +             return PTR_ERR(driver->idmdrd_rst_ctrl);
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "crmu-ctrl");
>> +     driver->crmu_usb2_ctrl = devm_ioremap_resource(dev, res);
>> +     if (IS_ERR(driver->crmu_usb2_ctrl))
>> +             return PTR_ERR(driver->crmu_usb2_ctrl);
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "usb2-strap");
>> +     driver->usb2h_strap_reg = devm_ioremap_resource(dev, res);
>> +     if (IS_ERR(driver->usb2h_strap_reg))
>> +             return PTR_ERR(driver->usb2h_strap_reg);
>> +
>> +      /* create extcon */
>> +     driver->id_gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
>> +     if (IS_ERR(driver->id_gpiod)) {
>> +             dev_err(dev, "failed to get ID GPIO\n");
>> +             return PTR_ERR(driver->id_gpiod);
>> +     }
>> +     driver->vbus_gpiod = devm_gpiod_get(&pdev->dev, "vbus", GPIOD_IN);
>> +     if (IS_ERR(driver->vbus_gpiod)) {
>> +             dev_err(dev, "failed to get VBUS GPIO\n");
>> +             return PTR_ERR(driver->vbus_gpiod);
>> +     }
>> +
>> +     driver->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
>> +     if (IS_ERR(driver->edev)) {
>> +             dev_err(dev, "failed to allocate extcon device\n");
>> +             return -ENOMEM;
>> +     }
>> +
>> +     ret = devm_extcon_dev_register(dev, driver->edev);
>> +     if (ret < 0) {
>> +             dev_err(dev, "failed to register extcon device\n");
>> +             goto extcon_free;
>> +     }
>> +
>> +     ret = gpiod_set_debounce(driver->id_gpiod, GPIO_DELAY * 1000);
>> +     if (ret < 0)
>> +             driver->debounce_jiffies = msecs_to_jiffies(GPIO_DELAY);
>> +
>> +     INIT_DELAYED_WORK(&driver->wq_extcon, extcon_work);
>> +
>> +     driver->id_irq = gpiod_to_irq(driver->id_gpiod);
>> +     if (driver->id_irq < 0) {
>> +             dev_err(dev, "failed to get ID IRQ\n");
>> +             ret = driver->id_irq;
>> +             goto extcon_unregister;
>> +     }
>> +     driver->vbus_irq = gpiod_to_irq(driver->vbus_gpiod);
>> +     if (driver->vbus_irq < 0) {
>> +             dev_err(dev, "failed to get ID IRQ\n");
>> +             ret = driver->vbus_irq;
>> +             goto extcon_unregister;
>> +     }
>> +
>> +     ret = devm_request_threaded_irq(dev, driver->id_irq, NULL,
>> +                                     gpio_irq_handler,
>> +                                     IRQF_TRIGGER_RISING |
>> +                                     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
>> +                                     "usb_id", driver);
>> +     if (ret < 0) {
>> +             dev_err(dev, "failed to request handler for ID IRQ\n");
>> +             goto extcon_unregister;
>> +     }
>> +     ret = devm_request_threaded_irq(dev, driver->vbus_irq, NULL,
>> +                                     gpio_irq_handler,
>> +                                     IRQF_TRIGGER_RISING |
>> +                                     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
>> +                                     "usb_vbus", driver);
>> +     if (ret < 0) {
>> +             dev_err(dev, "failed to request handler for VBUS IRQ\n");
>> +             goto extcon_unregister;
>> +     }
>> +
>> +     dev_set_drvdata(dev, driver);
>> +
>> +     /* Shutdown all ports. They can be powered up as required */
>> +     val = readl(driver->crmu_usb2_ctrl);
>> +     val &= ~(AFE_CORERDY_VDDC | PHY_RESETB);
>> +     writel(val, driver->crmu_usb2_ctrl);
>> +
>> +     data = driver->data;
>> +     data->phy = devm_phy_create(dev, dev->of_node, &ops);
>> +     if (IS_ERR(data->phy)) {
>> +             dev_err(dev, "Failed to create usb drd phy\n");
>> +             ret = PTR_ERR(data->phy);
>> +             goto extcon_unregister;
>> +     }
>> +
>> +     data->driver = driver;
>> +     phy_set_drvdata(data->phy, data);
>> +
>> +     phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
>> +     if (IS_ERR(phy_provider)) {
>> +             dev_err(dev, "Failed to register as phy provider\n");
>> +             ret = PTR_ERR(phy_provider);
>> +             goto extcon_unregister;
>> +     }
>> +
>> +     platform_set_drvdata(pdev, driver);
>> +
>> +     dev_info(dev, "Registered NS2 DRD Phy device\n");
>> +     queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
>> +                        driver->debounce_jiffies);
>> +
>> +     return 0;
>> +
>> +extcon_unregister:
>> +     devm_extcon_dev_unregister(dev, driver->edev);
>
> devm_* api's should take care of cleaning up itself. Do you really need this?

No.

>> +extcon_free:
>> +     devm_extcon_dev_free(dev, driver->edev);
>
> here too.

Ok
Will sent next patch version with these changes

Thanks,
Ravi

>
> Thanks
> Kishon



More information about the linux-arm-kernel mailing list