Hi,
On Wed, Jul 30, 2014 at 04:28:09PM +0100, Peter Griffin wrote:
> This patch adds the ST glue logic to manage the DWC3 HC
> on STiH407 SoC family. It manages the powerdown signal,
> and configures the internal glue logic and syscfg registers.
>
> Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
> Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
> Acked-by: Lee Jones <lee.jones@xxxxxxxxxx>
> ---
> drivers/usb/dwc3/Kconfig | 9 ++
> drivers/usb/dwc3/Makefile | 1 +
> drivers/usb/dwc3/dwc3-st.c | 336 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 346 insertions(+)
> create mode 100644 drivers/usb/dwc3/dwc3-st.c
>
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index 8eb996e..6c85c43 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -79,6 +79,15 @@ config USB_DWC3_KEYSTONE
> Support of USB2/3 functionality in TI Keystone2 platforms.
> Say 'Y' or 'M' here if you have one such device
>
> +config USB_DWC3_ST
> + tristate "STMicroelectronics Platforms"
> + depends on ARCH_STI && OF
> + default USB_DWC3_HOST
this seems wrong as USB_DWC3_{HOST,GADGET,DUAL_ROLE} are booleans and
USB_DWC3_ST is a tristate. Better to stick with defaulting to USB_DWC3
instead like all the others.
> + help
> + STMicroelectronics SoCs with one DesignWare Core USB3 IP
> + inside (i.e. STiH407).
> + Say 'Y' or 'M' if you have one such device.
> +
> comment "Debugging features"
>
> config USB_DWC3_DEBUG
> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> index 10ac3e7..11c9f54 100644
> --- a/drivers/usb/dwc3/Makefile
> +++ b/drivers/usb/dwc3/Makefile
> @@ -33,3 +33,4 @@ obj-$(CONFIG_USB_DWC3_OMAP) += dwc3-omap.o
> obj-$(CONFIG_USB_DWC3_EXYNOS) += dwc3-exynos.o
> obj-$(CONFIG_USB_DWC3_PCI) += dwc3-pci.o
> obj-$(CONFIG_USB_DWC3_KEYSTONE) += dwc3-keystone.o
> +obj-$(CONFIG_USB_DWC3_ST) += dwc3-st.o
> diff --git a/drivers/usb/dwc3/dwc3-st.c b/drivers/usb/dwc3/dwc3-st.c
> new file mode 100644
> index 0000000..227698f
> --- /dev/null
> +++ b/drivers/usb/dwc3/dwc3-st.c
> @@ -0,0 +1,336 @@
> +/**
> + * dwc3-st.c Support for dwc3 platform devices on ST Microelectronics platforms
> + *
> + * This is a small driver for the dwc3 to provide the glue logic
> + * to configure the controller. Tested on STi platforms.
> + *
> + * Copyright (C) 2014 Stmicroelectronics
> + *
> + * Author: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
> + * Contributors: Aymen Bouattay <aymen.bouattay@xxxxxx>
> + * Peter Griffin <peter.griffin@xxxxxxxxxx>
> + *
> + * 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; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * Inspired by dwc3-omap.c and dwc3-exynos.c.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/usb/of.h>
> +
> +#include "core.h"
> +#include "io.h"
> +
> +/* glue registers */
> +#define CLKRST_CTRL 0x00
> +#define AUX_CLK_EN BIT(0)
> +#define SW_PIPEW_RESET_N BIT(4)
> +#define EXT_CFG_RESET_N BIT(8)
> +/*
> + * 1'b0 : The host controller complies with the xHCI revision 0.96
> + * 1'b1 : The host controller complies with the xHCI revision 1.0
> + */
> +#define XHCI_REVISION BIT(12)
> +
> +#define USB2_VBUS_MNGMNT_SEL1 0x2C
> +/*
> + * For all fields in USB2_VBUS_MNGMNT_SEL1
> + * 2’b00 : Override value from Reg 0x30 is selected
> + * 2’b01 : utmiotg_<signal_name> from usb3_top is selected
> + * 2’b10 : pipew_<signal_name> from PIPEW instance is selected
> + * 2’b11 : value is 1'b0
> + */
> +#define USB2_VBUS_REG30 0x0
> +#define USB2_VBUS_UTMIOTG 0x1
> +#define USB2_VBUS_PIPEW 0x2
> +#define USB2_VBUS_ZERO 0x3
> +
> +#define SEL_OVERRIDE_VBUSVALID(n) (n << 0)
> +#define SEL_OVERRIDE_POWERPRESENT(n) (n << 4)
> +#define SEL_OVERRIDE_BVALID(n) (n << 8)
> +
> +/* Static DRD configuration */
> +#define USB_HOST_DEFAULT_MASK 0xffe
> +#define USB_SET_PORT_DEVICE 0x1
> +
> +/**
> + * struct st_dwc3 - dwc3-st driver private structure
> + * @dev: device pointer
> + * @glue_base: ioaddr for the glue registers
> + * @regmap: regmap pointer for getting syscfg
> + * @syscfg_reg_off: usb syscfg control offset
> + * @dr_mode: drd static host/device config
> + * @rstc_pwrdn: rest controller for powerdown signal
> + * @rstc_rst: reset controller for softreset signal
> + */
> +
> +struct st_dwc3 {
> + struct device *dev;
> + void __iomem *glue_base;
> + struct regmap *regmap;
> + int syscfg_reg_off;
> + enum usb_dr_mode dr_mode;
> + struct reset_control *rstc_pwrdn;
> + struct reset_control *rstc_rst;
> +};
> +
> +static inline u32 st_dwc3_readl(void __iomem *base, u32 offset)
> +{
> + return readl_relaxed(base + offset);
> +}
> +
> +static inline void st_dwc3_writel(void __iomem *base, u32 offset, u32 value)
> +{
> + writel_relaxed(value, base + offset);
why relaxed ?
> +}
> +
> +/**
> + * st_dwc3_drd_init: program the port
> + * @dwc3_data: driver private structure
> + * Description: this function is to program the port as either host or device
> + * according to the static configuration passed from devicetree.
> + * OTG and dual role are not yet supported!
> + */
> +static int st_dwc3_drd_init(struct st_dwc3 *dwc3_data)
> +{
> + u32 val;
> + int err;
> +
> + err = regmap_read(dwc3_data->regmap, dwc3_data->syscfg_reg_off, &val);
> + if (err)
> + return err;
> +
> + switch (dwc3_data->dr_mode) {
> + case USB_DR_MODE_PERIPHERAL:
> + val |= USB_SET_PORT_DEVICE;
> + dev_dbg(dwc3_data->dev, "Configuring as Device\n");
> + break;
> +
> + case USB_DR_MODE_HOST:
> + val &= USB_HOST_DEFAULT_MASK;
are you missing a ~ here ? Also, shouldn't you mask off the bits before
this switch ?
> + dev_dbg(dwc3_data->dev, "Configuring as Host\n");
> + break;
> +
> + default:
> + dev_err(dwc3_data->dev, "Unsupported mode of operation %d\n",
> + dwc3_data->dr_mode);
> + return -EINVAL;
> + }
> +
> + return regmap_write(dwc3_data->regmap, dwc3_data->syscfg_reg_off, val);
> +}
> +
> +/**
> + * st_dwc3_init: init the controller via glue logic
> + * @dwc3_data: driver private structure
> + */
> +static void st_dwc3_init(struct st_dwc3 *dwc3_data)
> +{
> +
this blank line isn't necessary.
> + u32 reg = st_dwc3_readl(dwc3_data->glue_base, CLKRST_CTRL);
> +
> + reg |= AUX_CLK_EN | EXT_CFG_RESET_N | XHCI_REVISION;
> + reg &= ~SW_PIPEW_RESET_N;
> + st_dwc3_writel(dwc3_data->glue_base, CLKRST_CTRL, reg);
> +
> + /* configure mux for vbus, powerpresent and bvalid signals */
> + reg = st_dwc3_readl(dwc3_data->glue_base, USB2_VBUS_MNGMNT_SEL1);
> +
> + reg |= SEL_OVERRIDE_VBUSVALID(USB2_VBUS_UTMIOTG) |
> + SEL_OVERRIDE_POWERPRESENT(USB2_VBUS_UTMIOTG) |
> + SEL_OVERRIDE_BVALID(USB2_VBUS_UTMIOTG);
> +
> + st_dwc3_writel(dwc3_data->glue_base, USB2_VBUS_MNGMNT_SEL1, reg);
> +
> + reg = st_dwc3_readl(dwc3_data->glue_base, CLKRST_CTRL);
> + reg |= SW_PIPEW_RESET_N;
> + st_dwc3_writel(dwc3_data->glue_base, CLKRST_CTRL, reg);
> +}
> +
> +static int st_dwc3_probe(struct platform_device *pdev)
> +{
> + struct st_dwc3 *dwc3_data;
> + struct resource *res;
> + struct device *dev = &pdev->dev;
> + struct device_node *node = dev->of_node, *child;
> + struct regmap *regmap;
> + int ret;
> +
> + dwc3_data = devm_kzalloc(dev, sizeof(*dwc3_data), GFP_KERNEL);
> + if (!dwc3_data)
> + return -ENOMEM;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg-glue");
> + dwc3_data->glue_base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(dwc3_data->glue_base))
> + return PTR_ERR(dwc3_data->glue_base);
> +
> + regmap = syscon_regmap_lookup_by_phandle(node, "st,syscfg");
> + if (IS_ERR(regmap))
> + return PTR_ERR(regmap);
> +
> + dma_set_coherent_mask(dev, dev->coherent_dma_mask);
> + dwc3_data->dev = dev;
> + dwc3_data->regmap = regmap;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-reg");
> + if (!res) {
> + ret = -ENXIO;
> + goto undo_platform_dev_alloc;
> + }
> +
> + dwc3_data->syscfg_reg_off = res->start;
> +
> + dev_dbg(&pdev->dev, "glue-logic addr 0x%p, syscfg-reg offset 0x%x\n",
> + dwc3_data->glue_base, dwc3_data->syscfg_reg_off);
looks like this message would be more of a dev_vdbg().
> + dwc3_data->rstc_pwrdn = devm_reset_control_get(dev, "powerdown");
> + if (IS_ERR(dwc3_data->rstc_pwrdn)) {
> + dev_err(&pdev->dev, "could not get power controller\n");
> + ret = PTR_ERR(dwc3_data->rstc_pwrdn);
> + goto undo_platform_dev_alloc;
> + }
> +
> + /* Manage PowerDown */
> + reset_control_deassert(dwc3_data->rstc_pwrdn);
> +
> + dwc3_data->rstc_rst = devm_reset_control_get(dev, "softreset");
> + if (IS_ERR(dwc3_data->rstc_rst)) {
> + dev_err(&pdev->dev, "could not get reset controller\n");
> + ret = PTR_ERR(dwc3_data->rstc_pwrdn);
> + goto undo_powerdown;
> + }
> +
> + /* Manage SoftReset */
> + reset_control_deassert(dwc3_data->rstc_rst);
> +
> + child = of_get_child_by_name(node, "dwc3");
> + if (!child) {
> + dev_err(&pdev->dev, "failed to find dwc3 core node\n");
> + ret = -ENODEV;
> + goto undo_softreset;
> + }
> +
> + dwc3_data->dr_mode = of_usb_get_dr_mode(child);
> +
> + /* Allocate and initialize the core */
> + ret = of_platform_populate(node, NULL, NULL, dev);
> + if (ret) {
> + dev_err(dev, "failed to add dwc3 core\n");
> + goto undo_softreset;
> + }
> +
> + /*
> + * Configure the USB port as device or host according to the static
> + * configuration passed from DT.
> + * DRD is the only mode currently supported so this will be enhanced
> + * as soon as OTG is available.
> + */
> + ret = st_dwc3_drd_init(dwc3_data);
> + if (ret) {
> + dev_err(dev, "drd initialisation failed\n");
> + goto undo_softreset;
> + }
> +
> + /* ST glue logic init */
> + st_dwc3_init(dwc3_data);
> +
> + platform_set_drvdata(pdev, dwc3_data);
> + return 0;
> +
> +undo_softreset:
> + reset_control_assert(dwc3_data->rstc_rst);
> +undo_powerdown:
> + reset_control_assert(dwc3_data->rstc_pwrdn);
> +undo_platform_dev_alloc:
> + platform_device_put(pdev);
> + return ret;
> +}
> +
> +
> +static int st_dwc3_remove_child(struct device *dev, void *c)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> +
> + of_device_unregister(pdev);
> +
> + return 0;
> +}
> +
> +static int st_dwc3_remove(struct platform_device *pdev)
> +{
> + struct st_dwc3 *dwc3_data = platform_get_drvdata(pdev);
> +
> + device_for_each_child(&pdev->dev, NULL, st_dwc3_remove_child);
> +
> + reset_control_assert(dwc3_data->rstc_pwrdn);
> + reset_control_assert(dwc3_data->rstc_rst);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int st_dwc3_suspend(struct device *dev)
> +{
> + struct st_dwc3 *dwc3_data = dev_get_drvdata(dev);
> +
> + reset_control_assert(dwc3_data->rstc_pwrdn);
> + reset_control_assert(dwc3_data->rstc_rst);
Two questions:
1) how would you handle the case when this device is a wakeup source ?
2) when resuming, wouldn't you have to reinitialize the entire core ?
--
balbi
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