| Message ID | 1385410581-12148-2-git-send-email-w-kwok2@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Mon, Nov 25, 2013 at 03:16:19PM -0500, WingMan Kwok wrote: > diff --git a/drivers/usb/dwc3/dwc3-keystone.c b/drivers/usb/dwc3/dwc3-keystone.c > new file mode 100644 > index 0000000..a4c9cbc > --- /dev/null > +++ b/drivers/usb/dwc3/dwc3-keystone.c > @@ -0,0 +1,272 @@ > +/** > + * dwc3-keystone.c - Keystone Specific Glue layer > + * > + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com > + * > + * Authors: WingMan Kwok <w-kwok2@ti.com> singular -> Author :-) there's only a single one. > + * This program is free software: you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 of > + * the License as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/clk.h> > +#include <linux/module.h> > +#include <linux/kernel.h> > +#include <linux/slab.h> > +#include <linux/interrupt.h> > +#include <linux/spinlock.h> > +#include <linux/platform_device.h> > +#include <linux/dma-mapping.h> > +#include <linux/ioport.h> > +#include <linux/io.h> > +#include <linux/of.h> > +#include <linux/of_platform.h> > +#include <linux/usb/usb_phy_gen_xceiv.h> > + > + > +#define BITS(n) (BIT(n) - 1) looks like unnecessary obfuscation. > +#define BITFIELD(x, s, n) (((x) & BITS(n)) << (s)) likewise. > +#define MASK 0xffffffff huh ? You probably want a better name here. > +#define PHY_REF_SSP_EN(x) BITFIELD(x, 29, 1) hmm, should be part of a PHY driver (drivers/phy/) > +static u64 kdwc3_dma_mask; > + > +struct kdwc3_phy_ctrl_regs { > + u32 phy_utmi; > + u32 phy_pipe; > + u32 phy_param_ctrl_1; > + u32 phy_param_ctrl_2; > + u32 phy_clock; > + u32 phy_pll; > +}; should be part of a PHY driver. Sorry, but I'll be very pedantic. > +struct kdwc3_irq_regs { > + u32 revision; > + u32 _rsvd0[3]; > + u32 sysconfig; > + u32 _rsvd1[1]; > + u32 irq_eoi; > + u32 _rsvd2[1]; > + struct { > + u32 raw_status; > + u32 status; > + u32 enable_set; > + u32 enable_clr; > + } irqs[16]; > +}; please use #define macros instead. > +struct dwc3_keystone { > + spinlock_t lock; > + struct device *dev; > + struct clk *clk; > + int irqn; > + > + struct kdwc3_phy_ctrl_regs __iomem *phy_ctrl; not part of this driver. > + struct kdwc3_irq_regs __iomem *usbss; > +}; > + > +static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) > +{ > + writel(1, &kdwc->usbss->irqs[kdwc->irqn].enable_set); I would like to have a define here, no magic constants. > +} > + > +static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) > +{ > + writel(0, &kdwc->usbss->irqs[kdwc->irqn].enable_set); > +} you want these two functions to be more generic, along the lines of: static void kdwc3_writel(void __iomem *base, u32 offset, u32 val) { writel(val, base + offset); } static u32 kdwc3_readl(void __iomem *base, u32 offset) { return readl(base + offset); } then you can add: static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) { u32 reg; reg = kdwc3_readl(kdwc->base, KEYSTONE_DWC3_IRQ); reg |= KEYSTONE_DWC3_IRQ_ENABLE; kdwc3_writel(kdwc->base, KEYSTONE_DWC3_IRQ, reg); } static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) { u32 reg; reg = kdwc3_readl(kdwc->base, KEYSTONE_DWC3_IRQ); reg &= ~KEYSTONE_DWC3_IRQ_ENABLE; kdwc3_writel(kdwc->base, KEYSTONE_DWC3_IRQ, reg); } this will be much more "future-safe". > +static int kdwc3_enable(struct dwc3_keystone *kdwc) > +{ > + int error; > + u32 val; > + > + kdwc->clk = devm_clk_get(kdwc->dev, "usb"); > + if (IS_ERR_OR_NULL(kdwc->clk)) { > + dev_err(kdwc->dev, "unable to get kdwc usb clock\n"); > + return -ENODEV; > + } > + > + val = readl(&kdwc->phy_ctrl->phy_clock); no PHY registers will ever be accessed from a glue layer ;-) This should all be part of a phy driver (drivers/phy/phy-keystone.c) and dwc3.ko will take care of the rest. > + writel(val | PHY_REF_SSP_EN(1), &kdwc->phy_ctrl->phy_clock); > + udelay(20); > + > + error = clk_prepare_enable(kdwc->clk); > + if (error < 0) { > + dev_dbg(kdwc->dev, "unable to enable usb clock, err %d\n", > + error); > + writel(val, &kdwc->phy_ctrl->phy_clock); > + return error; > + } > + > + /* soft reset usbss */ > + writel(1, &kdwc->usbss->sysconfig); shoul we access sysconfig registers from drivers ? How about using a reset driver ? (drivers/reset/). > + while (readl(&kdwc->usbss->sysconfig) & 1) > + ; infinite loop ? Never, please add a timeout. > + val = readl(&kdwc->usbss->revision); > + dev_info(kdwc->dev, "usbss revision %x\n", val); unnecessary dev_info(). You're not even decoding the revision information. > + return 0; > +} > + > +static void kdwc3_disable(struct dwc3_keystone *kdwc) > +{ > + u32 val; > + > + clk_disable_unprepare(kdwc->clk); > + > + val = readl(&kdwc->phy_ctrl->phy_clock); > + val &= ~PHY_REF_SSP_EN(MASK); > + writel(val, &kdwc->phy_ctrl->phy_clock); should not be done here. > +} > + > +static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc) > +{ > + struct dwc3_keystone *kdwc = _kdwc; > + int irqn = kdwc->irqn; why ? the irq argument should already be the correct IRQ number, right ? > + spin_lock(&kdwc->lock); > + writel(1, &kdwc->usbss->irqs[irqn].enable_clr); > + writel(1, &kdwc->usbss->irqs[irqn].status); > + writel(1, &kdwc->usbss->irqs[irqn].enable_set); no magic constants... > + writel(BIT(irqn), &kdwc->usbss->irq_eoi); > + spin_unlock(&kdwc->lock); > + > + return IRQ_HANDLED; > +} > + > +static int kdwc3_probe(struct platform_device *pdev) > +{ > + struct device_node *node = pdev->dev.of_node; > + struct device *dev = &pdev->dev; > + struct dwc3_keystone *kdwc; > + struct resource *res; > + int error, irq; > + > + if (!node) { > + dev_err(dev, "device node not found\n"); > + return -EINVAL; > + } if this will only be used on DT-based boot, node *must* be true. If it's not, we're dealing with a pretty critical bug, in which case we want a Kernel Oops to happen so we catch that bug, please drop this check. > + > + kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL); > + if (!kdwc) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, kdwc); > + > + spin_lock_init(&kdwc->lock); > + kdwc->dev = dev; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) { > + dev_err(dev, "missing usbss resource\n"); > + return -EINVAL; > + } > + > + kdwc->usbss = devm_ioremap_resource(dev, res); > + if (IS_ERR(kdwc->usbss)) { > + dev_err(dev, "ioremap failed on usbss region\n"); no need to print anything, devm_ioremap_resource() already prints sensible messages. > + return PTR_ERR(kdwc->usbss); > + } > + > + dev_dbg(dev, "usbss control start=%08x size=%d mapped=%08x\n", > + (u32)(res->start), (int)resource_size(res), > + (u32)(kdwc->usbss)); this is really unnecessary, if you really want to have it, move it to dev_vdbg(). > + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + if (!res) { > + dev_err(dev, "missing usb phy resource\n"); > + return -EINVAL; > + } > + > + kdwc->phy_ctrl = devm_ioremap_resource(dev, res); > + if (IS_ERR(kdwc->phy_ctrl)) { > + dev_err(dev, "ioremap failed on usb phy region\n"); > + return PTR_ERR(kdwc->phy_ctrl); > + } second resource should be part of the PHY driver. This is even more important considering you're using DT, we don't want to allow broken DTS data to be accepted. > + dev_dbg(dev, "phy control start=%08x size=%d mapped=%08x\n", > + (u32)(res->start), (int)resource_size(res), > + (u32)(kdwc->phy_ctrl)); unnecessary. > + kdwc3_dma_mask = dma_get_mask(dev); > + dev->dma_mask = &kdwc3_dma_mask; > + > + error = kdwc3_enable(kdwc); I would drop this function and just add your clk_prepare() here, then move clk_enable()/clk_disable() to ->runtime_resume/->runtime_suspend() respectively. Then you could just call pm_runtime_get_sync() when you need to access your registers and pm_runtime_put() when you want to drop the clock reference. this will even make PM implementation a lot easier for you going forward. > + if (error) > + return error; > + > + irq = platform_get_irq(pdev, 0); > + if (irq < 0) { > + dev_err(&pdev->dev, "missing irq\n"); > + goto err_irq; > + } > + > + error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED, > + "keystone-dwc3", kdwc); dev_name(dev) ?? If you happen to have multiple instances of a dwc3 core, it'll give it better names. > + if (error) { > + dev_err(dev, "failed to request IRQ #%d --> %d\n", > + irq, error); > + goto err_irq; > + } > + > + kdwc->irqn = 0; wait, what ? Can you describe how this part works ? Why do you even need this if it's alway zero ? > + kdwc3_enable_irqs(kdwc); > + > + error = of_platform_populate(node, NULL, NULL, dev); > + if (error) { > + dev_err(&pdev->dev, "failed to create dwc3 core\n"); > + goto err_core; > + } > + > + return 0; > + > +err_core: > + kdwc3_disable_irqs(kdwc); > +err_irq: > + kdwc3_disable(kdwc); > + > + return error; > +} > + > +static int kdwc3_remove(struct platform_device *pdev) > +{ > + struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); > + > + if (kdwc) { kdwc will never be true, you can drop this check. > + kdwc3_disable_irqs(kdwc); > + kdwc3_disable(kdwc); > + platform_set_drvdata(pdev, NULL); > + } > + return 0; > +} > + > +static const struct of_device_id kdwc3_of_match[] = { > + { .compatible = "ti,keystone-dwc3", }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, kdwc3_of_match); > + > +static struct platform_driver kdwc3_driver = { > + .probe = kdwc3_probe, > + .remove = kdwc3_remove, > + .driver = { > + .name = "keystone-dwc3", > + .owner = THIS_MODULE, > + .of_match_table = kdwc3_of_match, > + }, > +}; > + > +module_platform_driver(kdwc3_driver); > + > +MODULE_ALIAS("platform:keystone-dwc3"); > +MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer"); > -- > 1.7.9.5 >
On Monday 25 November 2013 03:39 PM, Felipe Balbi wrote: > Hi, > [...] > >> + kdwc3_dma_mask = dma_get_mask(dev); >> + dev->dma_mask = &kdwc3_dma_mask; >> + >> + error = kdwc3_enable(kdwc); > > I would drop this function and just add your clk_prepare() here, then > move clk_enable()/clk_disable() to ->runtime_resume/->runtime_suspend() > respectively. Then you could just call pm_runtime_get_sync() when you > need to access your registers and pm_runtime_put() when you want to drop > the clock reference. > > this will even make PM implementation a lot easier for you going > forward. > Just to make the PM runtime part clear, there are few issues with PM core clock layer [1], hence drivers is using clock layer. Its trivial to update the driver though once the issue is sorted out. Meanwhile driver development continue to be with clock calls. Regards, Santosh [1] https://groups.google.com/forum/#!msg/linux.kernel/w5gFxFsIK-c/jYcnRET_EdAJ
On Mon, Nov 25, 2013 at 07:49:01PM -0500, Santosh Shilimkar wrote: > On Monday 25 November 2013 03:39 PM, Felipe Balbi wrote: > > Hi, > > > > [...] > > > > >> + kdwc3_dma_mask = dma_get_mask(dev); > >> + dev->dma_mask = &kdwc3_dma_mask; > >> + > >> + error = kdwc3_enable(kdwc); > > > > I would drop this function and just add your clk_prepare() here, then > > move clk_enable()/clk_disable() to ->runtime_resume/->runtime_suspend() > > respectively. Then you could just call pm_runtime_get_sync() when you > > need to access your registers and pm_runtime_put() when you want to drop > > the clock reference. > > > > this will even make PM implementation a lot easier for you going > > forward. > > > Just to make the PM runtime part clear, there are few issues with PM > core clock layer [1], hence drivers is using clock layer. Its trivial > to update the driver though once the issue is sorted out. > > Meanwhile driver development continue to be with clock calls. I don't mind having those clock calls, just suggested a different placement for them.
On Tuesday 26 November 2013 12:16 PM, Felipe Balbi wrote: > On Mon, Nov 25, 2013 at 07:49:01PM -0500, Santosh Shilimkar wrote: >> On Monday 25 November 2013 03:39 PM, Felipe Balbi wrote: >>> Hi, >>> >> >> [...] >> >>> >>>> + kdwc3_dma_mask = dma_get_mask(dev); >>>> + dev->dma_mask = &kdwc3_dma_mask; >>>> + >>>> + error = kdwc3_enable(kdwc); >>> >>> I would drop this function and just add your clk_prepare() here, then >>> move clk_enable()/clk_disable() to ->runtime_resume/->runtime_suspend() >>> respectively. Then you could just call pm_runtime_get_sync() when you >>> need to access your registers and pm_runtime_put() when you want to drop >>> the clock reference. >>> >>> this will even make PM implementation a lot easier for you going >>> forward. >>> >> Just to make the PM runtime part clear, there are few issues with PM >> core clock layer [1], hence drivers is using clock layer. Its trivial >> to update the driver though once the issue is sorted out. >> >> Meanwhile driver development continue to be with clock calls. > > I don't mind having those clock calls, just suggested a different > placement for them. > I got that part. Just wanted to clear the runtime PM part. Regards, Santosh
On 11/26/2013 1:46 AM, WingMan Kwok wrote: > Add Keystone platform specific glue layer to support > USB3 Host mode. > > Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> > Cc: Felipe Balbi <balbi@ti.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: WingMan Kwok <w-kwok2@ti.com> > --- > drivers/usb/dwc3/Kconfig | 7 + > drivers/usb/dwc3/Makefile | 1 + > drivers/usb/dwc3/dwc3-keystone.c | 272 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 280 insertions(+) > create mode 100644 drivers/usb/dwc3/dwc3-keystone.c <snip> > + error = of_platform_populate(node, NULL, NULL, dev); > + if (error) { > + dev_err(&pdev->dev, "failed to create dwc3 core\n"); > + goto err_core; > + } > + > + return 0; > + > +err_core: > + kdwc3_disable_irqs(kdwc); > +err_irq: > + kdwc3_disable(kdwc); > + > + return error; > +} > + > +static int kdwc3_remove(struct platform_device *pdev) > +{ > + struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); > + > + if (kdwc) { > + kdwc3_disable_irqs(kdwc); > + kdwc3_disable(kdwc); > + platform_set_drvdata(pdev, NULL); > + } > + return 0; > +} > + You need to unregister the child nodes in remove. Also why can't the dwc3-omap driver be reused, Felipe?? I believe the TI wrapper for Keystone is similar to that of AM437x or OMAP5. > +static const struct of_device_id kdwc3_of_match[] = { > + { .compatible = "ti,keystone-dwc3", }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, kdwc3_of_match); > + > +static struct platform_driver kdwc3_driver = { > + .probe = kdwc3_probe, > + .remove = kdwc3_remove, > + .driver = { > + .name = "keystone-dwc3", > + .owner = THIS_MODULE, > + .of_match_table = kdwc3_of_match, > + }, > +}; > + > +module_platform_driver(kdwc3_driver); > + > +MODULE_ALIAS("platform:keystone-dwc3"); > +MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
Hi, On Wed, Nov 27, 2013 at 02:49:54PM +0530, George Cherian wrote: > >+ error = of_platform_populate(node, NULL, NULL, dev); > >+ if (error) { > >+ dev_err(&pdev->dev, "failed to create dwc3 core\n"); > >+ goto err_core; > >+ } > >+ > >+ return 0; > >+ > >+err_core: > >+ kdwc3_disable_irqs(kdwc); > >+err_irq: > >+ kdwc3_disable(kdwc); > >+ > >+ return error; > >+} > >+ > >+static int kdwc3_remove(struct platform_device *pdev) > >+{ > >+ struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); > >+ > >+ if (kdwc) { > >+ kdwc3_disable_irqs(kdwc); > >+ kdwc3_disable(kdwc); > >+ platform_set_drvdata(pdev, NULL); > >+ } > >+ return 0; > >+} > >+ > > You need to unregister the child nodes in remove. > Also why can't the dwc3-omap driver be reused, Felipe?? > I believe the TI wrapper for Keystone is similar to that of AM437x or > OMAP5. it is very similar indeed, if it can be easily re-use that glue, I'd rather not add another.
On Wednesday 27 November 2013 12:41 PM, Felipe Balbi wrote: > Hi, > > On Wed, Nov 27, 2013 at 02:49:54PM +0530, George Cherian wrote: >>> + error = of_platform_populate(node, NULL, NULL, dev); >>> + if (error) { >>> + dev_err(&pdev->dev, "failed to create dwc3 core\n"); >>> + goto err_core; >>> + } >>> + >>> + return 0; >>> + >>> +err_core: >>> + kdwc3_disable_irqs(kdwc); >>> +err_irq: >>> + kdwc3_disable(kdwc); >>> + >>> + return error; >>> +} >>> + >>> +static int kdwc3_remove(struct platform_device *pdev) >>> +{ >>> + struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); >>> + >>> + if (kdwc) { >>> + kdwc3_disable_irqs(kdwc); >>> + kdwc3_disable(kdwc); >>> + platform_set_drvdata(pdev, NULL); >>> + } >>> + return 0; >>> +} >>> + >> >> You need to unregister the child nodes in remove. >> Also why can't the dwc3-omap driver be reused, Felipe?? >> I believe the TI wrapper for Keystone is similar to that of AM437x or >> OMAP5. > > it is very similar indeed, if it can be easily re-use that glue, I'd > rather not add another. > Initial idea was actually to use same driver but the integration IP is quite different on Keystone vs OMAP which lead to have a separate glue layer. They look similar but there are differences in terms of phys, interrupts, register space. And also non OTG support, runtime PM vs clock etc for now. After all the glue is really a very small code describes the integration details thanks to nice abstracted dwc3 core layer. So as discussed over irc, keeping the separate glue is preferred but do let us know if you think otherwise. Regards, Santosh
On Wed, Nov 27, 2013 at 01:32:04PM -0500, Santosh Shilimkar wrote: > On Wednesday 27 November 2013 12:41 PM, Felipe Balbi wrote: > > Hi, > > > > On Wed, Nov 27, 2013 at 02:49:54PM +0530, George Cherian wrote: > >>> + error = of_platform_populate(node, NULL, NULL, dev); > >>> + if (error) { > >>> + dev_err(&pdev->dev, "failed to create dwc3 core\n"); > >>> + goto err_core; > >>> + } > >>> + > >>> + return 0; > >>> + > >>> +err_core: > >>> + kdwc3_disable_irqs(kdwc); > >>> +err_irq: > >>> + kdwc3_disable(kdwc); > >>> + > >>> + return error; > >>> +} > >>> + > >>> +static int kdwc3_remove(struct platform_device *pdev) > >>> +{ > >>> + struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); > >>> + > >>> + if (kdwc) { > >>> + kdwc3_disable_irqs(kdwc); > >>> + kdwc3_disable(kdwc); > >>> + platform_set_drvdata(pdev, NULL); > >>> + } > >>> + return 0; > >>> +} > >>> + > >> > >> You need to unregister the child nodes in remove. > >> Also why can't the dwc3-omap driver be reused, Felipe?? > >> I believe the TI wrapper for Keystone is similar to that of AM437x or > >> OMAP5. > > > > it is very similar indeed, if it can be easily re-use that glue, I'd > > rather not add another. > > > Initial idea was actually to use same driver but the integration IP > is quite different on Keystone vs OMAP which lead to have a separate > glue layer. They look similar but there are differences in terms of phys, > interrupts, register space. And also non OTG support, runtime PM > vs clock etc for now. All of those can be easily taken care of: a) PHY -> different phy driver b) non-OTG -> there's a register on dwc3 which we can use c) runtime vs clock -> we can add optional clock support on dwc3-omap.c what *really* prevents us from using the same, is register layout and the fact that on OMAP, nobody wants drivers accessing SYS* registers (a mistake IMO). That would be a lot more difficult to make generic. BTW, OMAP isn't OTG either, it doesn't support the OTG specification even though it can act in both roles. Same applies for keystone, if I'm reading my docs correctly. > After all the glue is really a very small code describes the integration > details thanks to nice abstracted dwc3 core layer. So as discussed > over irc, keeping the separate glue is preferred but do let us know > if you think otherwise. yeah, let's keep it separate. Keystone is, in general, an entire new SoC architecture anyway.
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig index 70fc430..e2c730f 100644 --- a/drivers/usb/dwc3/Kconfig +++ b/drivers/usb/dwc3/Kconfig @@ -70,6 +70,13 @@ config USB_DWC3_PCI One such PCIe-based platform is Synopsys' PCIe HAPS model of this IP. +config USB_DWC3_KEYSTONE + tristate "Texas Instruments Keystone2 Platforms" + default USB_DWC3 + help + Support of USB2/3 functionality in TI Keystone2 platforms. + Say 'Y' or 'M' here 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 dd17601..10ac3e7 100644 --- a/drivers/usb/dwc3/Makefile +++ b/drivers/usb/dwc3/Makefile @@ -32,3 +32,4 @@ endif 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 diff --git a/drivers/usb/dwc3/dwc3-keystone.c b/drivers/usb/dwc3/dwc3-keystone.c new file mode 100644 index 0000000..a4c9cbc --- /dev/null +++ b/drivers/usb/dwc3/dwc3-keystone.c @@ -0,0 +1,272 @@ +/** + * dwc3-keystone.c - Keystone Specific Glue layer + * + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com + * + * Authors: WingMan Kwok <w-kwok2@ti.com> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 of + * the License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/usb/usb_phy_gen_xceiv.h> + + +#define BITS(n) (BIT(n) - 1) +#define BITFIELD(x, s, n) (((x) & BITS(n)) << (s)) +#define MASK 0xffffffff +#define PHY_REF_SSP_EN(x) BITFIELD(x, 29, 1) + +static u64 kdwc3_dma_mask; + +struct kdwc3_phy_ctrl_regs { + u32 phy_utmi; + u32 phy_pipe; + u32 phy_param_ctrl_1; + u32 phy_param_ctrl_2; + u32 phy_clock; + u32 phy_pll; +}; + +struct kdwc3_irq_regs { + u32 revision; + u32 _rsvd0[3]; + u32 sysconfig; + u32 _rsvd1[1]; + u32 irq_eoi; + u32 _rsvd2[1]; + struct { + u32 raw_status; + u32 status; + u32 enable_set; + u32 enable_clr; + } irqs[16]; +}; + +struct dwc3_keystone { + spinlock_t lock; + struct device *dev; + struct clk *clk; + int irqn; + + struct kdwc3_phy_ctrl_regs __iomem *phy_ctrl; + struct kdwc3_irq_regs __iomem *usbss; +}; + +static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) +{ + writel(1, &kdwc->usbss->irqs[kdwc->irqn].enable_set); +} + +static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) +{ + writel(0, &kdwc->usbss->irqs[kdwc->irqn].enable_set); +} + +static int kdwc3_enable(struct dwc3_keystone *kdwc) +{ + int error; + u32 val; + + kdwc->clk = devm_clk_get(kdwc->dev, "usb"); + if (IS_ERR_OR_NULL(kdwc->clk)) { + dev_err(kdwc->dev, "unable to get kdwc usb clock\n"); + return -ENODEV; + } + + val = readl(&kdwc->phy_ctrl->phy_clock); + writel(val | PHY_REF_SSP_EN(1), &kdwc->phy_ctrl->phy_clock); + udelay(20); + + error = clk_prepare_enable(kdwc->clk); + if (error < 0) { + dev_dbg(kdwc->dev, "unable to enable usb clock, err %d\n", + error); + writel(val, &kdwc->phy_ctrl->phy_clock); + return error; + } + + /* soft reset usbss */ + writel(1, &kdwc->usbss->sysconfig); + while (readl(&kdwc->usbss->sysconfig) & 1) + ; + + val = readl(&kdwc->usbss->revision); + dev_info(kdwc->dev, "usbss revision %x\n", val); + + return 0; +} + +static void kdwc3_disable(struct dwc3_keystone *kdwc) +{ + u32 val; + + clk_disable_unprepare(kdwc->clk); + + val = readl(&kdwc->phy_ctrl->phy_clock); + val &= ~PHY_REF_SSP_EN(MASK); + writel(val, &kdwc->phy_ctrl->phy_clock); +} + +static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc) +{ + struct dwc3_keystone *kdwc = _kdwc; + int irqn = kdwc->irqn; + + spin_lock(&kdwc->lock); + writel(1, &kdwc->usbss->irqs[irqn].enable_clr); + writel(1, &kdwc->usbss->irqs[irqn].status); + writel(1, &kdwc->usbss->irqs[irqn].enable_set); + writel(BIT(irqn), &kdwc->usbss->irq_eoi); + spin_unlock(&kdwc->lock); + + return IRQ_HANDLED; +} + +static int kdwc3_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct device *dev = &pdev->dev; + struct dwc3_keystone *kdwc; + struct resource *res; + int error, irq; + + if (!node) { + dev_err(dev, "device node not found\n"); + return -EINVAL; + } + + kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL); + if (!kdwc) + return -ENOMEM; + + platform_set_drvdata(pdev, kdwc); + + spin_lock_init(&kdwc->lock); + kdwc->dev = dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "missing usbss resource\n"); + return -EINVAL; + } + + kdwc->usbss = devm_ioremap_resource(dev, res); + if (IS_ERR(kdwc->usbss)) { + dev_err(dev, "ioremap failed on usbss region\n"); + return PTR_ERR(kdwc->usbss); + } + + dev_dbg(dev, "usbss control start=%08x size=%d mapped=%08x\n", + (u32)(res->start), (int)resource_size(res), + (u32)(kdwc->usbss)); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res) { + dev_err(dev, "missing usb phy resource\n"); + return -EINVAL; + } + + kdwc->phy_ctrl = devm_ioremap_resource(dev, res); + if (IS_ERR(kdwc->phy_ctrl)) { + dev_err(dev, "ioremap failed on usb phy region\n"); + return PTR_ERR(kdwc->phy_ctrl); + } + + dev_dbg(dev, "phy control start=%08x size=%d mapped=%08x\n", + (u32)(res->start), (int)resource_size(res), + (u32)(kdwc->phy_ctrl)); + + kdwc3_dma_mask = dma_get_mask(dev); + dev->dma_mask = &kdwc3_dma_mask; + + error = kdwc3_enable(kdwc); + if (error) + return error; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "missing irq\n"); + goto err_irq; + } + + error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED, + "keystone-dwc3", kdwc); + if (error) { + dev_err(dev, "failed to request IRQ #%d --> %d\n", + irq, error); + goto err_irq; + } + + kdwc->irqn = 0; + + kdwc3_enable_irqs(kdwc); + + error = of_platform_populate(node, NULL, NULL, dev); + if (error) { + dev_err(&pdev->dev, "failed to create dwc3 core\n"); + goto err_core; + } + + return 0; + +err_core: + kdwc3_disable_irqs(kdwc); +err_irq: + kdwc3_disable(kdwc); + + return error; +} + +static int kdwc3_remove(struct platform_device *pdev) +{ + struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); + + if (kdwc) { + kdwc3_disable_irqs(kdwc); + kdwc3_disable(kdwc); + platform_set_drvdata(pdev, NULL); + } + return 0; +} + +static const struct of_device_id kdwc3_of_match[] = { + { .compatible = "ti,keystone-dwc3", }, + {}, +}; +MODULE_DEVICE_TABLE(of, kdwc3_of_match); + +static struct platform_driver kdwc3_driver = { + .probe = kdwc3_probe, + .remove = kdwc3_remove, + .driver = { + .name = "keystone-dwc3", + .owner = THIS_MODULE, + .of_match_table = kdwc3_of_match, + }, +}; + +module_platform_driver(kdwc3_driver); + +MODULE_ALIAS("platform:keystone-dwc3"); +MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
Add Keystone platform specific glue layer to support USB3 Host mode. Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: WingMan Kwok <w-kwok2@ti.com> --- drivers/usb/dwc3/Kconfig | 7 + drivers/usb/dwc3/Makefile | 1 + drivers/usb/dwc3/dwc3-keystone.c | 272 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 280 insertions(+) create mode 100644 drivers/usb/dwc3/dwc3-keystone.c