On Fri, Nov 22, 2013 at 10:53:55AM +0100, Marc Kleine-Budde wrote: > From: Peter Chen <peter.chen@xxxxxxxxxxxxx> > > 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> > --- > 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 1c94fc5..f2855be 100644 > --- a/drivers/usb/chipidea/ci.h > +++ b/drivers/usb/chipidea/ci.h > @@ -173,6 +173,8 @@ struct ci_hdrc { > struct dentry *debugfs; > bool id_event; > bool b_sess_valid_event; > + /* imx28 needs swp instruction for writing */ > + bool imx28_write_fix; > }; Please remove the comment, and add it to the kernel doc style comment above. Peter > > static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci) > @@ -253,6 +255,26 @@ 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, void __iomem *addr) > +{ > + __asm__ ("swp %0, %0, [%1]" : : "r"(val), "r"(addr)); > +} > +#else > +static inline void imx28_ci_writel(u32 val, 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); > + else > + iowrite32(val, addr); > +} > + > /** > * hw_write: writes to a hw register > * @reg: register index > @@ -266,7 +288,7 @@ static inline void hw_write(struct ci_hdrc *ci, enum ci_hw_regs reg, > data = (ioread32(ci->hw_bank.regmap[reg]) & ~mask) > | (data & mask); > > - iowrite32(data, ci->hw_bank.regmap[reg]); > + __hw_write(ci, data, ci->hw_bank.regmap[reg]); > } > > /** > @@ -281,7 +303,7 @@ static inline u32 hw_test_and_clear(struct ci_hdrc *ci, enum ci_hw_regs reg, > { > u32 val = ioread32(ci->hw_bank.regmap[reg]) & mask; > > - iowrite32(val, ci->hw_bank.regmap[reg]); > + __hw_write(ci, val, ci->hw_bank.regmap[reg]); > return val; > } > > diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c > index 98f45f1..40e1ed1 100644 > --- a/drivers/usb/chipidea/core.c > +++ b/drivers/usb/chipidea/core.c > @@ -531,6 +531,8 @@ static int ci_hdrc_probe(struct platform_device *pdev) > > ci->dev = dev; > ci->platdata = dev->platform_data; > + ci->imx28_write_fix = !!(ci->platdata->flags & > + CI_HDRC_IMX28_WRITE_FIX); > > ret = hw_device_init(ci, base); > if (ret < 0) { > diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c > index 59e6020..06fd042 100644 > --- a/drivers/usb/chipidea/host.c > +++ b/drivers/usb/chipidea/host.c > @@ -65,6 +65,7 @@ static int host_start(struct ci_hdrc *ci) > ehci->caps = ci->hw_bank.cap; > ehci->has_hostpc = ci->hw_bank.lpm; > ehci->has_tdi_phy_lpm = ci->hw_bank.lpm; > + ehci->imx28_write_fix = ci->imx28_write_fix; > > if (ci->platdata->reg_vbus) { > ret = regulator_enable(ci->platdata->reg_vbus); > diff --git a/include/linux/usb/chipidea.h b/include/linux/usb/chipidea.h > index 7d39967..708bd11 100644 > --- a/include/linux/usb/chipidea.h > +++ b/include/linux/usb/chipidea.h > @@ -24,6 +24,7 @@ struct ci_hdrc_platform_data { > * but otg is not supported (no register otgsc). > */ > #define CI_HDRC_DUAL_ROLE_NOT_OTG BIT(4) > +#define CI_HDRC_IMX28_WRITE_FIX BIT(5) > enum usb_dr_mode dr_mode; > #define CI_HDRC_CONTROLLER_RESET_EVENT 0 > #define CI_HDRC_CONTROLLER_STOPPED_EVENT 1 > -- > 1.8.4.2 > > -- Best Regards, Peter Chen -- 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
