Re: [PATCH 4/4] usb: chipidea: imx: set over current polarity per dts setting

[Peter Chen <hzpeterchen-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

On Mon, Jul 18, 2016 at 07:15:47PM +0800, Li Jun wrote:
> With over-current-polarity property added, imx usb over current
> polarity can be configed to be low or high active, since the default
> setting value(0) is for active high, so keep this setting for those
> legacy platforms without this property specified.
> 
> Signed-off-by: Li Jun <jun.li-3arQi8VN3Tc@public.gmane.org>
> ---
>  drivers/usb/chipidea/ci_hdrc_imx.c |  9 +++++++++
>  drivers/usb/chipidea/ci_hdrc_imx.h |  1 +
>  drivers/usb/chipidea/usbmisc_imx.c | 30 +++++++++++++++++++++++++-----
>  3 files changed, 35 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c
> index dedc33e..61e712b 100644
> --- a/drivers/usb/chipidea/ci_hdrc_imx.c
> +++ b/drivers/usb/chipidea/ci_hdrc_imx.c
> @@ -140,6 +140,15 @@ static struct imx_usbmisc_data *usbmisc_get_init_data(struct device *dev)
>  	if (of_find_property(np, "disable-over-current", NULL))
>  		data->disable_oc = 1;
>  
> +	if (!of_property_read_u32(np, "over-current-polarity", &ret))
> +		data->oc_polarity = ret ? 1 : 0;
> +	else
> +		/*
> +		 * Keep the oc polarity setting of legacy
> +		 * platforms unchanged.
> +		 */
> +		data->oc_polarity = 1;

We may can't ensure that, since there are lots of i.mx platforms, eg
from imx27 to imx7.
   
If the user does not assign oc polarity at DT, we need to read it from
register.

Peter
> +
>  	if (of_find_property(np, "external-vbus-divider", NULL))
>  		data->evdo = 1;
>  
> diff --git a/drivers/usb/chipidea/ci_hdrc_imx.h b/drivers/usb/chipidea/ci_hdrc_imx.h
> index 635717e..409aa5ca8 100644
> --- a/drivers/usb/chipidea/ci_hdrc_imx.h
> +++ b/drivers/usb/chipidea/ci_hdrc_imx.h
> @@ -17,6 +17,7 @@ struct imx_usbmisc_data {
>  	int index;
>  
>  	unsigned int disable_oc:1; /* over current detect disabled */
> +	unsigned int oc_polarity:1; /* over current polarity if oc enabled */
>  	unsigned int evdo:1; /* set external vbus divider option */
>  };
>  
> diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
> index ab8b027..193dbe4 100644
> --- a/drivers/usb/chipidea/usbmisc_imx.c
> +++ b/drivers/usb/chipidea/usbmisc_imx.c
> @@ -56,6 +56,7 @@
>  
>  #define MX6_BM_NON_BURST_SETTING	BIT(1)
>  #define MX6_BM_OVER_CUR_DIS		BIT(7)
> +#define MX6_BM_OVER_CUR_POLARITY	BIT(8)
>  #define MX6_BM_WAKEUP_ENABLE		BIT(10)
>  #define MX6_BM_ID_WAKEUP		BIT(16)
>  #define MX6_BM_VBUS_WAKEUP		BIT(17)
> @@ -266,11 +267,18 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
>  
>  	spin_lock_irqsave(&usbmisc->lock, flags);
>  
> +	reg = readl(usbmisc->base + data->index * 4);
>  	if (data->disable_oc) {
> -		reg = readl(usbmisc->base + data->index * 4);
> -		writel(reg | MX6_BM_OVER_CUR_DIS,
> -			usbmisc->base + data->index * 4);
> +		reg |= MX6_BM_OVER_CUR_DIS;
> +	} else if (data->oc_polarity == 1) {
> +		/* High active */
> +		reg &= ~(MX6_BM_OVER_CUR_DIS | MX6_BM_OVER_CUR_POLARITY);
> +	} else {
> +		/* Low active */
> +		reg &= ~MX6_BM_OVER_CUR_DIS;
> +		reg |= MX6_BM_OVER_CUR_POLARITY;
>  	}
> +	writel(reg, usbmisc->base + data->index * 4);
>  
>  	/* SoC non-burst setting */
>  	reg = readl(usbmisc->base + data->index * 4);
> @@ -365,10 +373,18 @@ static int usbmisc_imx7d_init(struct imx_usbmisc_data *data)
>  		return -EINVAL;
>  
>  	spin_lock_irqsave(&usbmisc->lock, flags);
> +	reg = readl(usbmisc->base);
>  	if (data->disable_oc) {
> -		reg = readl(usbmisc->base);
> -		writel(reg | MX6_BM_OVER_CUR_DIS, usbmisc->base);
> +		reg |= MX6_BM_OVER_CUR_DIS;
> +	} else if (data->oc_polarity == 1) {
> +		/* High active */
> +		reg &= ~(MX6_BM_OVER_CUR_DIS | MX6_BM_OVER_CUR_POLARITY);
> +	} else {
> +		/* Low active */
> +		reg &= ~MX6_BM_OVER_CUR_DIS;
> +		reg |= MX6_BM_OVER_CUR_POLARITY;
>  	}
> +	writel(reg, usbmisc->base);
>  
>  	reg = readl(usbmisc->base + MX7D_USBNC_USB_CTRL2);
>  	reg &= ~MX7D_USB_VBUS_WAKEUP_SOURCE_MASK;
> @@ -492,6 +508,10 @@ static const struct of_device_id usbmisc_imx_dt_ids[] = {
>  		.compatible = "fsl,imx6ul-usbmisc",
>  		.data = &imx6sx_usbmisc_ops,
>  	},
> +	{
> +		.compatible = "fsl,imx7d-usbmisc",
> +		.data = &imx7d_usbmisc_ops,
> +	},
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, usbmisc_imx_dt_ids);
> -- 
> 1.9.1
> 
> 
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-- 

Best Regards,
Peter Chen
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