Re: [PATCH v2 3/3] phy: cygnus-usbphy: Add Broadcom Cygnus USB phy driver
From: Arun Ramamurthy
Date: Tue Apr 14 2015 - 18:04:27 EST
Hi Kishon
I will address your comments on multi level if and error checking.
I have replied to your comments on phy power on and power off. Thanks
Arun
On 15-04-03 08:14 AM, Kishon Vijay Abraham I wrote:
Hi,
On Thursday 02 April 2015 02:20 AM, Arun Ramamurthy wrote:
This driver adds support for USB 2.0 host and device phy for
Broadcom's Cygnus chipset. The host controller is connected to
three separate phys and one of the phys (port 2) is connected to
the device controller
Reviewed-by: Ray Jui <rjui@xxxxxxxxxxxx>
Reviewed-by: Scott Branden <sbranden@xxxxxxxxxxxx>
Signed-off-by: Arun Ramamurthy <arun.ramamurthy@xxxxxxxxxxxx>
---
drivers/phy/Kconfig | 12 +
drivers/phy/Makefile | 1 +
drivers/phy/phy-bcm-cygnus-usb.c | 484
+++++++++++++++++++++++++++++++++++++++
3 files changed, 497 insertions(+)
create mode 100644 drivers/phy/phy-bcm-cygnus-usb.c
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 2962de2..0aa62dc 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -291,4 +291,16 @@ config PHY_QCOM_UFS
help
Support for UFS PHY on QCOM chipsets.
+config PHY_BCM_CYGNUS_USB
+ tristate "Broadcom Cygnus USB PHY support"
+ depends on OF
+ depends on ARCH_BCM_CYGNUS || COMPILE_TEST
+ select GENERIC_PHY
+ default ARCH_BCM_CYGNUS
+ help
+ Enable this to support the USB PHY in Broadcom's Cygnus chip.
+ The phys are capable of supporting host mode for all ports
+ and device mode for port 2. The host or device configuration is
+ read from the device tree.
+
endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index f080e1b..47a37fa 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_GENERIC_PHY) += phy-core.o
obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o
obj-$(CONFIG_PHY_BERLIN_SATA) += phy-berlin-sata.o
obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY) += phy-armada375-usb2.o
+obj-$(CONFIG_PHY_BCM_CYGNUS_USB) += phy-bcm-cygnus-usb.o
obj-$(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
diff --git a/drivers/phy/phy-bcm-cygnus-usb.c
b/drivers/phy/phy-bcm-cygnus-usb.c
new file mode 100644
index 0000000..b017e3b
--- /dev/null
+++ b/drivers/phy/phy-bcm-cygnus-usb.c
@@ -0,0 +1,484 @@
+/*
+ * Copyright (C) 2015 Broadcom Corporation
+ *
+ * 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/phy/phy.h>
+#include <linux/delay.h>
+
+#define CDRU_USBPHY_CLK_RST_SEL_OFFSET 0x11b4
+#define CDRU_USBPHY2_HOST_DEV_SEL_OFFSET 0x11b8
+#define CDRU_SPARE_REG_0_OFFSET 0x1238
+#define CRMU_USB_PHY_AON_CTRL_OFFSET 0x00028
+#define CDRU_USB_DEV_SUSPEND_RESUME_CTRL_OFFSET 0x1210
+#define CDRU_USBPHY_P0_STATUS_OFFSET 0x11D0
+#define CDRU_USBPHY_P1_STATUS_OFFSET 0x11E8
+#define CDRU_USBPHY_P2_STATUS_OFFSET 0x1200
+#define CDRU_USBPHY_USBPHY_ILDO_ON_FLAG 1
+#define CDRU_USBPHY_USBPHY_PLL_LOCK 0
+#define CDRU_USB_DEV_SUSPEND_RESUME_CTRL_DISABLE 0
+#define PHY2_DEV_HOST_CTRL_SEL_HOST 1
+
+#define CRMU_USBPHY_P0_AFE_CORERDY_VDDC 1
+#define CRMU_USBPHY_P0_RESETB 2
+#define CRMU_USBPHY_P1_AFE_CORERDY_VDDC 9
+#define CRMU_USBPHY_P1_RESETB 10
+#define CRMU_USBPHY_P2_AFE_CORERDY_VDDC 17
+#define CRMU_USBPHY_P2_RESETB 18
+
+#define USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET 0x0408
+#define USB2_IDM_IDM_IO_CONTROL_DIRECT__clk_enable 0
Did you run checkpatch on this patch?
I did run checkpatch and it passed. However I can see that the
indentation is ok, I will address that.
+#define USB2_IDM_IDM_RESET_CONTROL_OFFSET 0x0800
+#define USB2_IDM_IDM_RESET_CONTROL__RESET 0
+
+#define PLL_LOCK_RETRY_COUNT 1000
+#define MAX_PHY_PORTS 3
+
+static int power_bit[] = {CRMU_USBPHY_P0_AFE_CORERDY_VDDC,
+ CRMU_USBPHY_P1_AFE_CORERDY_VDDC,
+ CRMU_USBPHY_P2_AFE_CORERDY_VDDC};
+static int reset_bit[] = {CRMU_USBPHY_P0_RESETB,
+ CRMU_USBPHY_P1_RESETB,
+ CRMU_USBPHY_P2_RESETB};
+static int status_reg[] = {CDRU_USBPHY_P0_STATUS_OFFSET,
+ CDRU_USBPHY_P1_STATUS_OFFSET,
+ CDRU_USBPHY_P2_STATUS_OFFSET};
+
+struct bcm_phy_instance;
+
+struct bcm_phy_driver {
+ void __iomem *usbphy_regs;
+ void __iomem *usb2h_idm_regs;
+ void __iomem *usb2d_idm_regs;
+ struct bcm_phy_instance *ports[MAX_PHY_PORTS];
+ spinlock_t lock;
+ bool idm_host_enabled;
+};
+
+struct bcm_phy_instance {
+ struct bcm_phy_driver *driver;
+ struct phy *generic_phy;
+ int port_no;
+ bool host_mode; /* true - Host, false - device */
+ bool power;
+};
+
+static inline int bcm_phy_cdru_usbphy_status_wait(u32 usb_reg, int
reg_bit,
+ struct bcm_phy_driver *phy_driver)
+{
+ /* Wait for the PLL lock status */
+ int retry = PLL_LOCK_RETRY_COUNT;
+ u32 reg_val;
+
+ do {
+ udelay(1);
+ reg_val = readl(phy_driver->usbphy_regs +
+ usb_reg);
+ if (reg_val & (1 << reg_bit))
+ return 0;
+ } while (--retry > 0);
+
+ return -EBUSY;
+
+}
+
+static struct phy *bcm_usb_phy_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct bcm_phy_driver *phy_driver = dev_get_drvdata(dev);
+ struct bcm_phy_instance *port = NULL;
+ int i;
+
+ if (!phy_driver)
+ return ERR_PTR(-EINVAL);
use ENODEV here to make phy_optional_get happy.
+
+ if (WARN_ON(args->args_count != 1))
+ return ERR_PTR(-EINVAL);
same here..
+
+ if (WARN_ON(args->args[0] < 0 || args->args[0] > 1))
+ return ERR_PTR(-EINVAL);
here..
+
+ for (i = 0; i < ARRAY_SIZE(phy_driver->ports); i++) {
+ struct bcm_phy_instance *p = phy_driver->ports[i];
+
+ if (p && p->generic_phy->dev.of_node == args->np) {
+ port = p;
+ break;
+ }
+ }
+
+ if (!port) {
+ dev_err(dev, "Failed to locate phy %s\n", args->np->name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ port->host_mode = args->args[0];
+
+ return port->generic_phy;
+}
+
+static int bcm_phy_init(struct phy *generic_phy)
+{
+ struct bcm_phy_instance *port = phy_get_drvdata(generic_phy);
+ struct bcm_phy_driver *phy_driver = port->driver;
+ unsigned long flags;
+ u32 reg_val;
+
+ spin_lock_irqsave(&phy_driver->lock, flags);
if (port->port_no != 2)
return;
avoids multi level if..else.
+
+ /*
+ * Only PORT 2 is capable of being device and host
+ * Default setting is device, check if it is set to host.
+ */
+ if (port->port_no == 2) {
+ if (port->host_mode) {
+ writel(PHY2_DEV_HOST_CTRL_SEL_HOST,
+ phy_driver->usbphy_regs +
+ CDRU_USBPHY2_HOST_DEV_SEL_OFFSET);
+ } else {
+ /*
+ * Disable suspend/resume signals to device controller
+ * when a port is in device mode.
+ */
+ reg_val = readl(phy_driver->usbphy_regs +
+ CDRU_USB_DEV_SUSPEND_RESUME_CTRL_OFFSET);
+ reg_val |=
+ 1 << CDRU_USB_DEV_SUSPEND_RESUME_CTRL_DISABLE;
+ writel(reg_val, phy_driver->usbphy_regs +
+ CDRU_USB_DEV_SUSPEND_RESUME_CTRL_OFFSET);
+ }
+ }
+
+ spin_unlock_irqrestore(&phy_driver->lock, flags);
+ return 0;
+}
+
+static int bcm_phy_shutdown(struct phy *generic_phy)
+{
+ struct bcm_phy_instance *port = phy_get_drvdata(generic_phy);
+ struct bcm_phy_driver *phy_driver = port->driver;
+ unsigned long flags;
+ int i;
+ u32 reg_val, powered_on_phy;
+ bool power_off_flag = true;
+
+ spin_lock_irqsave(&phy_driver->lock, flags);
+
+ /* power down the phy */
+ reg_val = readl(phy_driver->usbphy_regs +
+ CRMU_USB_PHY_AON_CTRL_OFFSET);
+ reg_val &= ~(1 << power_bit[port->port_no]);
+ reg_val &= ~(1 << reset_bit[port->port_no]);
+ writel(reg_val, phy_driver->usbphy_regs +
+ CRMU_USB_PHY_AON_CTRL_OFFSET);
+ port->power = false;
+
+ /*
+ * If a port is configured to device and it is being shutdown,
+ * turn off the clocks to the usb device controller.
+ */
+ if (port->port_no == 2 && !port->host_mode) {
+ reg_val = readl(phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+ reg_val &= ~(1 << USB2_IDM_IDM_IO_CONTROL_DIRECT__clk_enable);
+ writel(reg_val, phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+
+ reg_val = readl(phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ reg_val |= 1 << USB2_IDM_IDM_RESET_CONTROL__RESET;
+ writel(reg_val, phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
just do a spin_unlock_irqrestore and return here. With that we can remove
multiple levels of if..else.
+ } else {
+ /*
+ * If the phy being shutdown provides clock and reset to
+ * the host controller, change it do a different powered on phy
%s/do/to/
Won't this cause a glitch or something?
We might submit patches for this later, we are still doing some testing.
+ * If all phys are powered off, shut of the host controller
+ */
+ reg_val = readl(phy_driver->usbphy_regs +
+ CDRU_USBPHY_CLK_RST_SEL_OFFSET);
+ powered_on_phy = reg_val;
+ if (reg_val == port->port_no) {
+ for (i = 0; i < ARRAY_SIZE(phy_driver->ports); i++) {
+ if (phy_driver->ports[i] &&
+ phy_driver->ports[i]->power &&
+ phy_driver->ports[i]->host_mode) {
+ power_off_flag = false;
+ powered_on_phy = i;
"break" here?
+ }
+ }
+ }
+
+ if (power_off_flag) {
+ /*
+ * Put the host controller into reset state and
+ * disable clock.
+ */
+ reg_val = readl(phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+ reg_val &=
+ ~(1 << USB2_IDM_IDM_IO_CONTROL_DIRECT__clk_enable);
+ writel(reg_val, phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+
+ reg_val = readl(phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ reg_val |= (1 << USB2_IDM_IDM_RESET_CONTROL__RESET);
+ writel(reg_val, phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ phy_driver->idm_host_enabled = 0;
+ } else {
+ writel(powered_on_phy, phy_driver->usbphy_regs +
+ CDRU_USBPHY_CLK_RST_SEL_OFFSET);
+ }
+ }
+
+ spin_unlock_irqrestore(&phy_driver->lock, flags);
+
+ return 0;
+}
+
+static int bcm_phy_poweron(struct phy *generic_phy)
+{
+ struct bcm_phy_instance *port = phy_get_drvdata(generic_phy);
+ struct bcm_phy_driver *phy_driver = port->driver;
+ unsigned long flags;
+ int ret;
+ u32 reg_val;
+ bool clock_reset_flag = true;
+
+ spin_lock_irqsave(&phy_driver->lock, flags);
+
+ /* Bring the AFE block out of reset to start powering up the PHY */
+ reg_val = readl(phy_driver->usbphy_regs +
CRMU_USB_PHY_AON_CTRL_OFFSET);
+ reg_val |= 1 << power_bit[port->port_no];
+ writel(reg_val, phy_driver->usbphy_regs +
CRMU_USB_PHY_AON_CTRL_OFFSET);
+
+ /* Check for power on and PLL lock */
+ ret = bcm_phy_cdru_usbphy_status_wait(status_reg[port->port_no],
+ CDRU_USBPHY_USBPHY_ILDO_ON_FLAG, phy_driver);
+ if (ret < 0) {
+ dev_err(&generic_phy->dev,
+ "Timed out waiting for USBPHY_ILDO_ON_FLAG on port %d",
+ port->port_no);
+ goto err_shutdown;
+ }
+ ret = bcm_phy_cdru_usbphy_status_wait(status_reg[port->port_no],
+ CDRU_USBPHY_USBPHY_PLL_LOCK, phy_driver);
+ if (ret < 0) {
+ dev_err(&generic_phy->dev,
+ "Timed out waiting for USBPHY_PLL_LOCK on port %d",
+ port->port_no);
+ goto err_shutdown;
+ }
+ port->power = true;
+
+ /* Check if the port 2 is configured for device */
+ if (port->port_no == 2 && !port->host_mode) {
+ /*
+ * Enable clock to USB device and get the USB device
+ * out of reset.
+ */
+ reg_val = readl(phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+ reg_val |= 1 << USB2_IDM_IDM_IO_CONTROL_DIRECT__clk_enable;
+ writel(reg_val, phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+
+ reg_val = readl(phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ reg_val &= ~(1 << USB2_IDM_IDM_RESET_CONTROL__RESET);
+ writel(reg_val, phy_driver->usb2d_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+
+ } else {
+ reg_val = readl(phy_driver->usbphy_regs +
+ CDRU_USBPHY_CLK_RST_SEL_OFFSET);
+
+ /*
+ * Check if the phy that is configured to provide clock
+ * and reset is powered on.
+ */
+ if (reg_val >= 0 && reg_val < ARRAY_SIZE(phy_driver->ports))
+ if (phy_driver->ports[reg_val])
+ if (phy_driver->ports[reg_val]->power)
+ clock_reset_flag = false;
+
+ /* if not set the current phy */
+ if (clock_reset_flag) {
+ reg_val = port->port_no;
+ writel(reg_val, phy_driver->usbphy_regs +
+ CDRU_USBPHY_CLK_RST_SEL_OFFSET);
Not sure if this is the right thing to do. We don't want to be powering on
some other PHY when the request was to enable this PHY. Same w.r.t
shutdown.
This logic is to check if the phy specified in the
CDRU_USBPHY_CLK_RST_SEL_OFFSET is turned on. If it is not, the register
value is changed to this current phy that is being powered on. We do not
power on any other phys
+ }
+ }
+
+ if (!phy_driver->idm_host_enabled) {
+ /* Enable clock to USB and get the USB out of reset */
What if one PHY resets the USB when another is using it?
This reset is for the HOST controller and not the phy. The
idm_host_enabled flag will prevent a PHY from powering on and resetting
the controller if another phy has already done so.
+ reg_val = readl(phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+ reg_val |= 1 << USB2_IDM_IDM_IO_CONTROL_DIRECT__clk_enable;
+ writel(reg_val, phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_IO_CONTROL_DIRECT_OFFSET);
+
+ reg_val = readl(phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ reg_val &= ~(1 << USB2_IDM_IDM_RESET_CONTROL__RESET);
+ writel(reg_val, phy_driver->usb2h_idm_regs +
+ USB2_IDM_IDM_RESET_CONTROL_OFFSET);
+ phy_driver->idm_host_enabled = true;
+ }
+
+ spin_unlock_irqrestore(&phy_driver->lock, flags);
+ return 0;
+
+err_shutdown:
+ spin_unlock_irqrestore(&phy_driver->lock, flags);
+ bcm_phy_shutdown(generic_phy);
+ return ret;
+}
+
+static struct phy_ops ops = {
+ .init = bcm_phy_init,
+ .power_on = bcm_phy_poweron,
+ .power_off = bcm_phy_shutdown,
+};
+
+static const struct of_device_id bcm_phy_dt_ids[] = {
+ { .compatible = "brcm,cygnus-usb-phy", },
+ { }
+};
+
+static int bcm_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct bcm_phy_driver *phy_driver;
+ struct phy_provider *phy_provider;
+ struct device_node *child;
+ struct resource *res;
+ int error;
+ u32 reg_val;
+
+ phy_driver = devm_kzalloc(dev, sizeof(struct bcm_phy_driver),
+ GFP_KERNEL);
+ if (!phy_driver)
+ return -ENOMEM;
+
+ spin_lock_init(&phy_driver->lock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
check return value of res.
will fix
+ phy_driver->usbphy_regs = devm_ioremap_nocache(dev, res->start,
+ resource_size(res));
+ if (!phy_driver->usbphy_regs) {
+ dev_err(dev, "Failed to remap usbphy_regs\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
same here..
will fix
+ phy_driver->usb2h_idm_regs = devm_ioremap_nocache(dev, res->start,
+ resource_size(res));
+ if (!phy_driver->usb2h_idm_regs) {
+ dev_err(dev, "Failed to remap usb2h_idm_regs\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
here too..
will fix
+ phy_driver->usb2d_idm_regs = devm_ioremap_nocache(dev, res->start,
+ resource_size(res));
+ if (!phy_driver->usb2d_idm_regs) {
+ dev_err(dev, "Failed to remap usb2d_idm_regs\n");
+ return -ENOMEM;
+ }
+
+ dev_set_drvdata(dev, phy_driver);
+
+ phy_driver->idm_host_enabled = false;
+
+ /* Shut down all ports. They can be powered up as required */
+ reg_val = readl(phy_driver->usbphy_regs +
+ CRMU_USB_PHY_AON_CTRL_OFFSET);
+ reg_val &= ~(1 << CRMU_USBPHY_P0_AFE_CORERDY_VDDC);
+ reg_val &= ~(1 << CRMU_USBPHY_P0_RESETB);
+ reg_val &= ~(1 << CRMU_USBPHY_P1_AFE_CORERDY_VDDC);
+ reg_val &= ~(1 << CRMU_USBPHY_P1_RESETB);
+ reg_val &= ~(1 << CRMU_USBPHY_P2_AFE_CORERDY_VDDC);
+ reg_val &= ~(1 << CRMU_USBPHY_P2_RESETB);
+ writel(reg_val, phy_driver->usbphy_regs +
+ CRMU_USB_PHY_AON_CTRL_OFFSET);
+
+ for_each_available_child_of_node(dev->of_node, child) {
+ struct bcm_phy_instance *port;
+ u32 port_no;
+
+ if (of_property_read_u32(child, "reg", &port_no)) {
+ dev_err(dev, "missing reg property in node %s\n",
+ child->name);
+ return -EINVAL;
+ }
+
+ if (port_no >= ARRAY_SIZE(phy_driver->ports)) {
+ dev_err(dev, "invalid reg in node %s: %u\n",
+ child->name, port_no);
+ return -EINVAL;
+ }
+
+ port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ port->generic_phy = devm_phy_create(dev, child, &ops);
+ if (IS_ERR(port->generic_phy)) {
+ error = PTR_ERR(port->generic_phy);
+ dev_err(dev, "Failed to create phy %u: %d",
+ port_no, error);
+ return error;
+ }
+
+ port->port_no = port_no;
+ port->driver = phy_driver;
+ phy_set_drvdata(port->generic_phy, port);
+
+ phy_driver->ports[port_no] = port;
+ }
+
+ phy_provider = devm_of_phy_provider_register(dev,
bcm_usb_phy_xlate);
+ if (IS_ERR(phy_provider)) {
+ error = PTR_ERR(phy_provider);
+ dev_err(dev, "Failed to register as phy provider: %d\n",
+ error);
+ return error;
+ }
+
+ platform_set_drvdata(pdev, phy_driver);
dev_get_drvdata should be sufficient.
I assume you mean dev_set_drvdata. Will fix.
Thanks
Kishon
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