[PATCHv4 2.6.34-rc4 5/7] mxc: Add generic USB HWinitialization for MX51

[Nguyen Dinh-R00091]

-----Original Message-----
From: Sascha Hauer [mailto:s.hauer at pengutronix.de] 
Sent: Saturday, April 17, 2010 9:07 PM
To: Nguyen Dinh-R00091
Cc: linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
linux at arm.linux.org.uk; valentin.longchamp at epfl.ch; daniel at caiaq.de;
grant.likely at secretlab.ca; bryan.wu at canonical.com;
amit.kucheria at canonical.com; Herring Robert-RA7055; Li Jun-R65092; Zhang
Lily-R58066
Subject: Re: [PATCHv4 2.6.34-rc4 5/7] mxc: Add generic USB
HWinitialization for MX51

On Fri, Apr 16, 2010 at 02:16:09PM -0500, Dinh.Nguyen at freescale.com
wrote:
> From: Dinh Nguyen <Dinh.Nguyen at freescale.com>
> 
> This patch adds USB HW initializiation code to /plat-mxc/ehci.c.
> 	-Stops and resets USB HW
> 	-Sets some specific PHY settings
> 	-Stop and restart the USB HW.
> Renames mxc_set_usbcontrol to mxc_initialize_usb_hw.
> 
> This patch applies to 2.6.34-rc4.
> 
> Signed-off-by: Dinh Nguyen <Dinh.Nguyen at freescale.com>
> ---
>  arch/arm/plat-mxc/ehci.c                  |  128
++++++++++++++++++++++++++++-
>  arch/arm/plat-mxc/include/mach/mxc_ehci.h |    2 +-
>  2 files changed, 127 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/plat-mxc/ehci.c b/arch/arm/plat-mxc/ehci.c index

> cb0b638..35ff1c1 100644
> --- a/arch/arm/plat-mxc/ehci.c
> +++ b/arch/arm/plat-mxc/ehci.c
> @@ -1,5 +1,6 @@
>  /*
>   * Copyright (c) 2009 Daniel Mack <daniel at caiaq.de>
> + * Copyright (C) 2010 Freescale Semiconductor, Inc.
>   *
>   * 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 @@ -18,6 +19,7 @@
>  
>  #include <linux/platform_device.h>
>  #include <linux/io.h>
> +#include <linux/delay.h>
>  
>  #include <mach/hardware.h>
>  #include <mach/mxc_ehci.h>
> @@ -50,9 +52,14 @@
>  #define MX35_H1_TLL_BIT		(1 << 5)
>  #define MX35_H1_USBTE_BIT	(1 << 4)
>  
> -int mxc_set_usbcontrol(int port, unsigned int flags)
> +int mxc_intialize_usb_hw(int port, unsigned int flags)
>  {
>  	unsigned int v;
> +	void __iomem *usb_base;
> +	u32 usbotg_base;
> +	u32 usbother_base;
> +	int timeout;
> +	int ret = 0;
>  #ifdef CONFIG_ARCH_MX3
>  	if (cpu_is_mx31()) {
>  		v = readl(MX31_IO_ADDRESS(MX31_OTG_BASE_ADDR + @@ -186,9
+193,126 
> @@ int mxc_set_usbcontrol(int port, unsigned int flags)
>  		return 0;
>  	}
>  #endif /* CONFIG_MACH_MX27 */
> +#ifdef CONFIG_ARCH_MX51
> +	if (cpu_is_mx51()) {
> +		usb_base = ioremap(MX51_OTG_BASE_ADDR, SZ_4K);
> +
> +		switch (port) {
> +		case 0:	/* OTG port */
> +			usbotg_base = (u32)usb_base + USBOTG_OFFSET;
> +			break;
> +		case 1:	/* Host 1 port */
> +			usbotg_base = (u32)usb_base + USBH1_OFFSET;
> +			break;
> +		default:
> +			printk(KERN_ERR"%s no such port %d\n", __func__,
port);
> +			ret = -ENOENT;
> +			goto error;
> +		}
> +		usbother_base = (u32)usb_base + USBOTHER_REGS_OFFSET;
> +
> +		/* Stop then Reset */
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v &= ~UCMD_RUN_STOP;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		timeout = 0x100000;
> +		while (--timeout && __raw_readl(usbotg_base +
USBCMD_OFFSET) & UCMD_RUN_STOP)
> +			cpu_relax();
> +		if (!timeout) {
> +			printk(KERN_ERR "%s could not stop usb
hardware\n", __func__);
> +			ret = -ETIMEDOUT;
> +			goto error;
> +		}
> +
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v |= UCMD_RESET;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		timeout = 0x100000;
> +		while (--timeout && __raw_readl(usbotg_base +
USBCMD_OFFSET) & UCMD_RESET)
> +			cpu_relax();
> +		if (!timeout) {
> +			printk(KERN_ERR "%s could not reset usb
hardware\n", __func__);
> +			ret = -ETIMEDOUT;
> +			goto error;
> +		}
> +
> +		switch (port) {
> +		case 0:	/*OTG port */
> +			v = __raw_readl(usbother_base +
USB_PHY_CTR_FUNC_OFFSET);
> +			v |= USB_UTMI_PHYCTRL_OC_DIS; /* OC is not used
*/
> +			__raw_writel(v, usbother_base +
USB_PHY_CTR_FUNC_OFFSET);
> +
> +			v = __raw_readl(usbother_base + USBCTRL_OFFSET);
> +			v &= ~(UCTRL_OPM | UCTRL_OWIE);/* OTG
wakeup/power mask disable */
> +			__raw_writel(v, usbother_base + USBCTRL_OFFSET);
> +
> +			/* Set the PHY clock to 19.2MHz */
> +			v = __raw_readl(usbother_base +
USB_PHY_CTR_FUNC2_OFFSET);
> +			v &= ~USB_UTMI_PHYCTRL2_PLLDIV_MASK;
> +			v |= 0x01;
> +			__raw_writel(v, usbother_base +
USB_PHY_CTR_FUNC2_OFFSET);
> +			break;

The sense of this funtion is to make the interface configuration,
especially the receiver type configurable with the flags parameter to
this function. This all looks very specific to your board, flags is
completely unused.

[Dinh] I think you're right Sascha, I think I can move this to the board
initialization. Do you agree Daniel?

Sascha


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