On Tue, Jul 19, 2016 at 02:31:41AM +0000, Jun Li wrote: > Hi > > > -----Original Message----- > > From: Peter Chen [mailto:hzpeterchen@xxxxxxxxx] > > Sent: Tuesday, July 19, 2016 9:57 AM > > To: Jun Li <jun.li@xxxxxxx> > > Cc: Peter Chen <peter.chen@xxxxxxx>; robh+dt@xxxxxxxxxx; > > shawnguo@xxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > Subject: Re: [PATCH 4/4] usb: chipidea: imx: set over current polarity per > > dts setting > > > > 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@xxxxxxx> > > > --- > > > 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. > > I suppose old platforms (other than i.mx6&7) should set either > "over-current-polarity" or "disable-over-current" if want to use > "data->oc_polarity". > The user may use old dtb and the latest kernel, so the introduced DT property should not affect old dtb platforms. > Do you mean read the register value before set "data->oc_polarity" here? yes, if there is a dts property, read it from DT; else, read it from the register. 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 = readl(oc_polarity); Then, when you set register for oc polarity, you can depend on the flag. reg = readl(usbmisc->base + data->index * 4); value = data->oc_polarity ? MX6_BM_OVER_CUR_POLARITY : 0; writel(reg | value, usbmisc->base + data->index * 4); > Even with that, as I still can't ensure all i.mx platforms have the same > mapping: > 0 <--> active high. > 1 <--> active low. > How should I set "data->oc_polarity" accordingly? Just keep current register value unchanging if there is no dts property. Peter > Li Jun > > > > 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 > > > > > > > > > _______________________________________________ > > > linux-arm-kernel mailing list > > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > > > -- > > > > Best Regards, > > Peter Chen -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html