On Mon, Jan 06, 2014 at 10:10:42AM +0800, Peter Chen wrote: > According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB > register error issue", All USB register write operations must > use the ARM SWP instruction. So, we implement special hw_write > and hw_test_and_clear for imx28. > > Discussion for it at below: > http://marc.info/?l=linux-usb&m=137996395529294&w=2 > > Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> > Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> > Tested-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> > --- > drivers/usb/chipidea/ci.h | 26 ++++++++++++++++++++++++-- > drivers/usb/chipidea/core.c | 2 ++ > drivers/usb/chipidea/host.c | 1 + > include/linux/usb/chipidea.h | 1 + > 4 files changed, 28 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h > index a71dc1c..e5506ce 100644 > --- a/drivers/usb/chipidea/ci.h > +++ b/drivers/usb/chipidea/ci.h > @@ -164,6 +164,7 @@ struct hw_bank { > * @id_event: indicates there is an id event, and handled at ci_otg_work > * @b_sess_valid_event: indicates there is a vbus event, and handled > * at ci_otg_work > + * @imx28_write_fix: Freescale imx28 needs swp instruction for writing > */ > struct ci_hdrc { > struct device *dev; > @@ -202,6 +203,7 @@ struct ci_hdrc { > struct dentry *debugfs; > bool id_event; > bool b_sess_valid_event; > + bool imx28_write_fix; > }; > > static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci) > @@ -250,6 +252,26 @@ static inline u32 hw_read(struct ci_hdrc *ci, enum ci_hw_regs reg, u32 mask) > return ioread32(ci->hw_bank.regmap[reg]) & mask; > } > > +#ifdef CONFIG_SOC_IMX28 > +static inline void imx28_ci_writel(u32 val, volatile void __iomem *addr) > +{ > + __asm__ ("swp %0, %0, [%1]" : : "r"(val), "r"(addr)); > +} > +#else > +static inline void imx28_ci_writel(u32 val, volatile void __iomem *addr) > +{ > +} > +#endif > + > +static inline void __hw_write(struct ci_hdrc *ci, u32 val, > + void __iomem *addr) > +{ > + if (IS_ENABLED(CONFIG_SOC_IMX28) && ci->imx28_write_fix) > + imx28_ci_writel(val, addr); Same here, this IS_ENABLED() isn't needed, right? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
