[PATCH v2 3/3] USB: cns3xxx: Add EHCI and OHCI bus glue for cns3xxx SOCs

Anton Vorontsov cbouatmailru at gmail.com
Wed Nov 24 11:25:12 EST 2010


On Tue, Nov 23, 2010 at 12:32:45AM +0800, mkl0301 at gmail.com wrote:
> From: Mac Lin <mkl0301 at gmail.com>
> 
> The CNS3XXX SOC has include USB EHCI and OHCI compatible controllers. This
> patch adds the necessary glue logic to allow ehci-hcd and ohci-hcd drivers to
> work on CNS3XXX
> 
> The EHCI and OHCI controllers share a common clock control and reset bit,
> therefore additional check for the timming of enabling and disabling is
> required. The USB bit of PLL Power Down Control is also shared by OTG, 24MHz
> UART clock, Crypto clock, PCIe reference clock, and Clock Scale Generator.
> Therefore we only ensure it is enabled, while not disabling it.
> 
> Signed-off-by: Mac Lin <mkl0301 at gmail.com>

Thanks for the patch!

A few (mostly cosmetic) comments down below.

> ---
>  drivers/usb/Kconfig             |    2 +
>  drivers/usb/host/Kconfig        |   15 ++++
>  drivers/usb/host/ehci-cns3xxx.c |  176 +++++++++++++++++++++++++++++++++++++++
>  drivers/usb/host/ehci-hcd.c     |    5 +
>  drivers/usb/host/ohci-cns3xxx.c |  171 +++++++++++++++++++++++++++++++++++++
>  drivers/usb/host/ohci-hcd.c     |    5 +
>  6 files changed, 374 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/usb/host/ehci-cns3xxx.c
>  create mode 100644 drivers/usb/host/ohci-cns3xxx.c
> 
> diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
> index 67eb377..5a7c8f1 100644
> --- a/drivers/usb/Kconfig
> +++ b/drivers/usb/Kconfig
> @@ -41,6 +41,7 @@ config USB_ARCH_HAS_OHCI
>  	default y if MFD_TC6393XB
>  	default y if ARCH_W90X900
>  	default y if ARCH_DAVINCI_DA8XX
> +	default y if ARCH_CNS3XXX
>  	# PPC:
>  	default y if STB03xxx
>  	default y if PPC_MPC52xx
> @@ -66,6 +67,7 @@ config USB_ARCH_HAS_EHCI
>  	default y if ARCH_AT91SAM9G45
>  	default y if ARCH_MXC
>  	default y if ARCH_OMAP3
> +	default y if ARCH_CNS3XXX
>  	default PCI
>  
>  # ARM SA1111 chips have a non-PCI based "OHCI-compatible" USB host interface.
> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
> index 6f4f8e6..f8970d1 100644
> --- a/drivers/usb/host/Kconfig
> +++ b/drivers/usb/host/Kconfig
> @@ -147,6 +147,14 @@ config USB_W90X900_EHCI
>  	---help---
>  		Enables support for the W90X900 USB controller
>  
> +config USB_CNS3XXX_EHCI
> +	bool "Cavium CNS3XXX EHCI Module"
> +	depends on USB_EHCI_HCD && ARCH_CNS3XXX
> +	---help---
> +	  Enable support for the CNS3XXX SOC's on-chip EHCI controller.
> +	  It is needed for high-speed (480Mbit/sec) USB 2.0 device
> +	  support.
> +
>  config USB_OXU210HP_HCD
>  	tristate "OXU210HP HCD support"
>  	depends on USB
> @@ -286,6 +294,13 @@ config USB_OHCI_HCD_SSB
>  
>  	  If unsure, say N.
>  
> +config USB_CNS3XXX_OHCI
> +	bool "Cavium CNS3XXX OHCI Module"
> +	depends on USB_OHCI_HCD && ARCH_CNS3XXX
> +	---help---
> +	  Enable support for the CNS3XXX SOC's on-chip OHCI controller.
> +	  It is needed for low-speed USB 1.0 device support.
> +
>  config USB_OHCI_BIG_ENDIAN_DESC
>  	bool
>  	depends on USB_OHCI_HCD
> diff --git a/drivers/usb/host/ehci-cns3xxx.c b/drivers/usb/host/ehci-cns3xxx.c
> new file mode 100644
> index 0000000..87c0ee8
> --- /dev/null
> +++ b/drivers/usb/host/ehci-cns3xxx.c
> @@ -0,0 +1,176 @@
> +/*
> + * Copyright 2008 Cavium Networks
> + *
> + * This file is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License, Version 2, as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <asm/atomic.h>
> +#include <mach/cns3xxx.h>
> +#include <mach/pm.h>
> +
> +static int cns3xxx_ehci_init(struct usb_hcd *hcd)
> +{
> +	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
> +	int retval = 0;

No need for = 0 initializer;

> +
> +	/* EHCI and OHCI share the same clock and power,
> +	 * resetting twice would cause the 1st controller been reset.
> +	 * Therefore only do power up  at the first up device, and
> +	 * power down at the last down device.
> +	 */
> +	if (1 == atomic_inc_return(&usb_pwr_ref)) {

1 == thing() isn't readable. I'd suggest to change the order.
If you fear for 'thing() = 1' type of errors, don't worry, gcc
will warn. ;-)

> +		cns3xxx_pwr_power_up(1<<PM_PLL_HM_PD_CTRL_REG_OFFSET_PLL_USB);

Spaces around <<.

> +		cns3xxx_pwr_clk_en(1<<PM_CLK_GATE_REG_OFFSET_USB_HOST);
> +		cns3xxx_pwr_soft_rst(1<<PM_SOFT_RST_REG_OFFST_USB_HOST);
> +	}
> +
> +	ehci->caps = hcd->regs;
> +	ehci->regs = hcd->regs
> +		+ HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
> +	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
> +
> +	hcd->has_tt = 0;
> +	ehci_reset(ehci);
> +
> +	retval = ehci_init(hcd);
> +	if (retval)
> +		return retval;
> +
> +	ehci_port_power(ehci, 0);
> +
> +	return retval;
> +}
> +
> +static const struct hc_driver cns3xxx_ehci_hc_driver = {
> +	.description		= hcd_name,
> +	.product_desc		= "CNS3XXX EHCI Host Controller",
> +	.hcd_priv_size		= sizeof(struct ehci_hcd),
> +	.irq			= ehci_irq,
> +	.flags			= HCD_MEMORY | HCD_USB2,
> +	.reset			= cns3xxx_ehci_init,
> +	.start			= ehci_run,
> +	.stop			= ehci_stop,
> +	.shutdown		= ehci_shutdown,
> +	.urb_enqueue		= ehci_urb_enqueue,
> +	.urb_dequeue		= ehci_urb_dequeue,
> +	.endpoint_disable	= ehci_endpoint_disable,
> +	.endpoint_reset		= ehci_endpoint_reset,
> +	.get_frame_number	= ehci_get_frame,
> +	.hub_status_data	= ehci_hub_status_data,
> +	.hub_control		= ehci_hub_control,
> +#ifdef CONFIG_PM
> +	.bus_suspend		= ehci_bus_suspend,
> +	.bus_resume		= ehci_bus_resume,
> +#endif
> +	.relinquish_port	= ehci_relinquish_port,
> +	.port_handed_over	= ehci_port_handed_over,
> +
> +	.clear_tt_buffer_complete	= ehci_clear_tt_buffer_complete,
> +};
> +
> +static int cns3xxx_ehci_probe(struct platform_device *pdev)
> +{
> +	struct usb_hcd *hcd;
> +	const struct hc_driver *driver = &cns3xxx_ehci_hc_driver;
> +	struct resource *res;
> +	int irq;
> +	int retval;
> +
> +	if (usb_disabled())
> +		return -ENODEV;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev,

the pdev->dev is very repetitive. Please, introduce
'struct device *dev';

> +			"Found HC with no IRQ. Check %s setup!\n",
> +			dev_name(&pdev->dev));

No need for dev_name() thing here. dev_err and friends will print
device name anyway.

> +		return -ENODEV;
> +	}

Empty line here.

> +	irq = res->start;
> +
> +	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
> +	if (!hcd)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev,
> +			"Found HC with no register addr. Check %s setup!\n",
> +			dev_name(&pdev->dev));
> +		retval = -ENODEV;
> +		goto err1;
> +	}
> +	hcd->rsrc_start = res->start;
> +	hcd->rsrc_len = res->end - res->start + 1;
> +
> +#ifdef CNS3XXX_USB_BASE_VIRT
> +	hcd->regs = (void __iomem *) CNS3XXX_USB_BASE_VIRT;
> +#else
> +	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
> +				driver->description)) {
> +		dev_dbg(&pdev->dev, "controller already in use\n");
> +		retval = -EBUSY;
> +		goto err1;
> +	}
> +
> +	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
> +

No need for this empty line.

> +	if (hcd->regs == NULL) {
> +		dev_dbg(&pdev->dev, "error mapping memory\n");
> +		retval = -EFAULT;
> +		goto err2;
> +	}
> +#endif
> +
> +	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
> +	if (retval == 0)
> +		return retval;
> +
> +#ifndef CNS3XXX_USB_BASE_VIRT
> +	iounmap(hcd->regs);
> +err2:
> +	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
> +#endif
> +err1:
> +	usb_put_hcd(hcd);
> +
> +	return retval;
> +}
> +
> +static int cns3xxx_ehci_remove(struct platform_device *pdev)
> +{
> +	struct usb_hcd *hcd = platform_get_drvdata(pdev);
> +
> +	usb_remove_hcd(hcd);
> +#ifndef CNS3XXX_USB_BASE_VIRT
> +	iounmap(hcd->regs);
> +	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
> +#endif
> +
> +	/* EHCI and OHCI share the same clock and power,
> +	 * resetting twice would cause the 1st controller been reset.
> +	 * Therefore only do power up  at the first up device, and
> +	 * power down at the last down device.
> +	 */

Please use canonical multiline comments, i.e.

/*
 * Text here.
 */

> +	if (0 == atomic_dec_return(&usb_pwr_ref))

if (atomic_dec_return(&usb_pwr_ref) == 0)

> +		cns3xxx_pwr_clk_dis(1<<PM_CLK_GATE_REG_OFFSET_USB_HOST);

spaces around <<.
> +
> +	usb_put_hcd(hcd);
> +
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;
> +}
> +
> +MODULE_ALIAS("platform:cns3xxx-ehci");
> +
> +static struct platform_driver cns3xxx_ehci_driver = {
> +	.probe = cns3xxx_ehci_probe,
> +	.remove = cns3xxx_ehci_remove,
> +	.driver = {
> +		.name = "cns3xxx-ehci",
> +	},
> +};
> diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
> index 502a7e6..c5dd1c3 100644
> --- a/drivers/usb/host/ehci-hcd.c
> +++ b/drivers/usb/host/ehci-hcd.c
> @@ -1216,6 +1216,11 @@ MODULE_LICENSE ("GPL");
>  #define PLATFORM_DRIVER		ehci_octeon_driver
>  #endif
>  
> +#ifdef CONFIG_USB_CNS3XXX_EHCI
> +#include "ehci-cns3xxx.c"
> +#define PLATFORM_DRIVER     cns3xxx_ehci_driver
> +#endif
> +
>  #if !defined(PCI_DRIVER) && !defined(PLATFORM_DRIVER) && \
>      !defined(PS3_SYSTEM_BUS_DRIVER) && !defined(OF_PLATFORM_DRIVER) && \
>      !defined(XILINX_OF_PLATFORM_DRIVER)
> diff --git a/drivers/usb/host/ohci-cns3xxx.c b/drivers/usb/host/ohci-cns3xxx.c
> new file mode 100644
> index 0000000..7617b8c
> --- /dev/null
> +++ b/drivers/usb/host/ohci-cns3xxx.c
> @@ -0,0 +1,171 @@
> +/*
> + * Copyright 2008 Cavium Networks
> + *
> + * This file is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License, Version 2, as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <asm/atomic.h>
> +#include <mach/cns3xxx.h>
> +#include <mach/pm.h>
> +
> +static int __devinit
> +cns3xxx_ohci_start(struct usb_hcd *hcd)
> +{
> +	struct ohci_hcd		*ohci = hcd_to_ohci(hcd);
> +	int			ret;

Either you indent declarations or not in the single file
(I'd prefer not to), otherwise it's very inconsistent.

> +
> +	/* EHCI and OHCI share the same clock and power,
> +	 * resetting twice would cause the 1st controller been reset.
> +	 * Therefore only do power up  at the first up device, and
> +	 * power down at the last down device.
> +	 */
> +	if (1 == atomic_inc_return(&usb_pwr_ref)) {

unreadable order

> +		cns3xxx_pwr_power_up(1<<PM_PLL_HM_PD_CTRL_REG_OFFSET_PLL_USB);

spaces

> +		cns3xxx_pwr_clk_en(1<<PM_CLK_GATE_REG_OFFSET_USB_HOST);
> +		cns3xxx_pwr_soft_rst(1<<PM_SOFT_RST_REG_OFFST_USB_HOST);
> +	}
> +
> +	ret = ohci_init(ohci);
> +	if (ret < 0)
> +		return ret;
> +
> +	ohci->num_ports = 1;
> +
> +	ret = ohci_run(ohci);
> +	if (ret < 0) {
> +		err("can't start %s", hcd->self.bus_name);
> +		ohci_stop(hcd);
> +		return ret;
> +	}
> +	return 0;
> +}
> +
> +static const struct hc_driver cns3xxx_ohci_hc_driver = {
> +	.description		= hcd_name,
> +	.product_desc		= "CNS3XXX OHCI Host controller",
> +	.hcd_priv_size		= sizeof(struct ohci_hcd),
> +	.irq			= ohci_irq,
> +	.flags			= HCD_USB11 | HCD_MEMORY,
> +	.start			= cns3xxx_ohci_start,
> +	.stop			= ohci_stop,
> +	.shutdown		= ohci_shutdown,
> +	.urb_enqueue		= ohci_urb_enqueue,
> +	.urb_dequeue		= ohci_urb_dequeue,
> +	.endpoint_disable	= ohci_endpoint_disable,
> +	.get_frame_number	= ohci_get_frame,
> +	.hub_status_data	= ohci_hub_status_data,
> +	.hub_control		= ohci_hub_control,
> +#ifdef CONFIG_PM
> +	.bus_suspend		= ohci_bus_suspend,
> +	.bus_resume		= ohci_bus_resume,
> +#endif
> +	.start_port_reset	= ohci_start_port_reset,
> +};
> +
> +static int cns3xxx_ohci_probe(struct platform_device *pdev)
> +{
> +	struct usb_hcd *hcd = NULL;

No need for = NULL initializer.

> +	const struct hc_driver *driver = &cns3xxx_ohci_hc_driver;
> +	struct resource *res;
> +	int irq;
> +	int retval;
> +
> +	if (usb_disabled())
> +		return -ENODEV;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev,
> +			"Found HC with no IRQ. Check %s setup!\n",
> +			dev_name(&pdev->dev));
> +		return -ENODEV;
> +	}
> +	irq = res->start;
> +
> +	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
> +	if (!hcd)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev,

pdev->dev is repetitive

> +			"Found HC with no register addr. Check %s setup!\n",
> +			dev_name(&pdev->dev));

no need for dev_name

> +		retval = -ENODEV;
> +		goto err1;
> +	}
> +	hcd->rsrc_start = res->start;
> +	hcd->rsrc_len = res->end - res->start + 1;
> +
> +#ifdef CNS3XXX_USB_OHCI_BASE_VIRT
> +	hcd->regs = (void __iomem *) CNS3XXX_USB_OHCI_BASE_VIRT;
> +#else
> +	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
> +			driver->description)) {
> +		dev_dbg(&pdev->dev, "controller already in use\n");
> +		retval = -EBUSY;
> +		goto err1;
> +	}
> +
> +	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
> +

I'd not place this empty line here.

> +	if (hcd->regs == NULL) {

I'd write it as if (!hcd->regs), which is more natural.

> +		dev_dbg(&pdev->dev, "error mapping memory\n");
> +		retval = -EFAULT;
> +		goto err2;
> +	}
> +#endif
> +
> +	ohci_hcd_init(hcd_to_ohci(hcd));
> +
> +	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
> +	if (retval == 0)
> +		return retval;
> +
> +#ifndef CNS3XXX_USB_OHCI_BASE_VIRT
> +	iounmap(hcd->regs);
> +err2:
> +	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
> +#endif
> +err1:
> +	usb_put_hcd(hcd);
> +	return retval;
> +}
> +
> +static int cns3xxx_ohci_remove(struct platform_device *pdev)
> +{
> +	struct usb_hcd *hcd = platform_get_drvdata(pdev);
> +
> +	usb_remove_hcd(hcd);
> +#ifndef CNS3XXX_USB_OHCI_BASE_VIRT
> +	iounmap(hcd->regs);
> +	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
> +#endif
> +
> +	/* EHCI and OHCI share the same clock and power,
> +	 * resetting twice would cause the 1st controller been reset.
> +	 * Therefore only do power up  at the first up device, and
> +	 * power down at the last down device.
> +	 */
> +	if (0 == atomic_dec_return(&usb_pwr_ref))

order

> +		cns3xxx_pwr_clk_dis(1<<PM_CLK_GATE_REG_OFFSET_USB_HOST);
> +
> +	usb_put_hcd(hcd);

Thanks,

-- 
Anton Vorontsov
Email: cbouatmailru at gmail.com



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