Message ID | 20160526154005.11558-2-thierry.reding@gmail.com |
---|---|
State | Deferred |
Headers | show |
On 05/26/2016 09:40 AM, Thierry Reding wrote: > From: Thierry Reding <treding@nvidia.com> > > All of these Tegra SoC generations have a ChipIdea UDC IP block that can > be used for device mode communication with a host. Implement rudimentary > support that doesn't allow switching between host and device modes. Are you sure this is correct for Tegra20? I ask because for the /host/ mode driver, there's a "has_hostpc" flag which is set to false for Tegra20 and true for all other SoCs. In the U-Boot device mode driver (if not in the kernel driver; I didn't check), there's a concept of "has hostpc" too. I might expect that flag to be set the same way for both drivers. That said, I /think/ the host and device HW are unrelated, so it's possible has_hostpc might be set differently for them. Unfortunately, we haven't enabled the device mode driver for any Tegra20 system in U-Boot so I can't tell whether we should enable has_hostpc for Tegra20's device mode driver. Still, if this code works then I guess it's likely correct... -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/26/2016 03:17 PM, Stephen Warren wrote: > On 05/26/2016 09:40 AM, Thierry Reding wrote: >> From: Thierry Reding <treding@nvidia.com> >> >> All of these Tegra SoC generations have a ChipIdea UDC IP block that can >> be used for device mode communication with a host. Implement rudimentary >> support that doesn't allow switching between host and device modes. > > Are you sure this is correct for Tegra20? I ask because for the /host/ > mode driver, there's a "has_hostpc" flag which is set to false for > Tegra20 and true for all other SoCs. In the U-Boot device mode driver > (if not in the kernel driver; I didn't check), there's a concept of "has > hostpc" too. I might expect that flag to be set the same way for both > drivers. That said, I /think/ the host and device HW are unrelated, so > it's possible has_hostpc might be set differently for them. > Unfortunately, we haven't enabled the device mode driver for any Tegra20 > system in U-Boot so I can't tell whether we should enable has_hostpc for > Tegra20's device mode driver. > > Still, if this code works then I guess it's likely correct... On the other hand, it looks like the kernel device mode driver might auto-detect this; in core.c:hw_device_init(), I see: reg = hw_read(ci, CAP_HCCPARAMS, HCCPARAMS_LEN) >> __ffs(HCCPARAMS_LEN); ci->hw_bank.lpm = reg; ... and in host.c:host_start(), I see: ehci->has_hostpc = ci->hw_bank.lpm; -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/usb/chipidea/Makefile b/drivers/usb/chipidea/Makefile index 518e445476c3..3532df6561d9 100644 --- a/drivers/usb/chipidea/Makefile +++ b/drivers/usb/chipidea/Makefile @@ -10,6 +10,7 @@ ci_hdrc-$(CONFIG_USB_OTG_FSM) += otg_fsm.o obj-$(CONFIG_USB_CHIPIDEA) += ci_hdrc_usb2.o obj-$(CONFIG_USB_CHIPIDEA) += ci_hdrc_msm.o obj-$(CONFIG_USB_CHIPIDEA) += ci_hdrc_zevio.o +obj-$(CONFIG_USB_CHIPIDEA) += ci_hdrc_tegra.o obj-$(CONFIG_USB_CHIPIDEA_PCI) += ci_hdrc_pci.o diff --git a/drivers/usb/chipidea/ci_hdrc_tegra.c b/drivers/usb/chipidea/ci_hdrc_tegra.c new file mode 100644 index 000000000000..d3cd68441856 --- /dev/null +++ b/drivers/usb/chipidea/ci_hdrc_tegra.c @@ -0,0 +1,109 @@ +/* + * Copyright (c) 2016, NVIDIA Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#include <linux/usb/chipidea.h> + +#include "ci.h" + +struct tegra_udc { + struct ci_hdrc_platform_data data; + struct platform_device *dev; + + struct usb_phy *phy; + struct clk *clk; +}; + +static const struct of_device_id tegra_udc_of_match[] = { + { .compatible = "nvidia,tegra20-udc" }, + { .compatible = "nvidia,tegra30-udc" }, + { .compatible = "nvidia,tegra114-udc" }, + { .compatible = "nvidia,tegra124-udc" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, tegra_udc_of_match); + +static int tegra_udc_probe(struct platform_device *pdev) +{ + struct tegra_udc *udc; + int err; + + udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL); + if (!udc) + return -ENOMEM; + + udc->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0); + if (IS_ERR(udc->phy)) { + err = PTR_ERR(udc->phy); + dev_err(&pdev->dev, "failed to get PHY: %d\n", err); + return err; + } + + udc->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(udc->clk)) { + err = PTR_ERR(udc->clk); + dev_err(&pdev->dev, "failed to get clock: %d\n", err); + return err; + } + + err = clk_prepare_enable(udc->clk); + if (err < 0) { + dev_err(&pdev->dev, "failed to enable clock: %d\n", err); + return err; + } + + /* setup and register ChipIdea HDRC device */ + udc->data.name = "tegra-udc"; + udc->data.capoffset = DEF_CAPOFFSET; + udc->data.flags = 0; + udc->data.usb_phy = udc->phy; + + udc->dev = ci_hdrc_add_device(&pdev->dev, pdev->resource, + pdev->num_resources, &udc->data); + if (IS_ERR(udc->dev)) { + err = PTR_ERR(udc->dev); + dev_err(&pdev->dev, "failed to add HDRC device: %d\n", err); + goto disable_clock; + } + + platform_set_drvdata(pdev, udc); + + return 0; + +disable_clock: + clk_disable_unprepare(udc->clk); + return err; +} + +static int tegra_udc_remove(struct platform_device *pdev) +{ + struct tegra_udc *udc = platform_get_drvdata(pdev); + + clk_disable_unprepare(udc->clk); + + return 0; +} + +static struct platform_driver tegra_udc_driver = { + .driver = { + .name = "tegra-udc", + .of_match_table = tegra_udc_of_match, + }, + .probe = tegra_udc_probe, + .remove = tegra_udc_remove, +}; +module_platform_driver(tegra_udc_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra USB device mode driver"); +MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>"); +MODULE_ALIAS("platform:tegra-udc"); +MODULE_LICENSE("GPL v2");