On Mon, 02 Mar 2015, Eric Anholt wrote: > This gets USB working on the Raspberry Pi without relying on U-Boot to > send the power message for us. Without it, you would get warnings > about fifo sizes and "dwc2_core_reset() HANG! Soft Reset > GRSTCTL=80000001" leading to a failed probe. > > Signed-off-by: Eric Anholt <eric@xxxxxxxxxx> > Cc: John Youn <johnyoun@xxxxxxxxxxxx> > --- > drivers/mailbox/bcm2835-mailbox-power.c | 5 +++++ > drivers/usb/dwc2/platform.c | 20 ++++++++++++++++++++ > 2 files changed, 25 insertions(+) > > diff --git a/drivers/mailbox/bcm2835-mailbox-power.c b/drivers/mailbox/bcm2835-mailbox-power.c > index f09c855..d0faca2 100644 > --- a/drivers/mailbox/bcm2835-mailbox-power.c > +++ b/drivers/mailbox/bcm2835-mailbox-power.c > @@ -31,6 +31,9 @@ struct bcm_mbox_power { > uint32_t response; > }; > > +bool bcm2835_mbox_power_initialized; > +EXPORT_SYMBOL_GPL(bcm2835_mbox_power_initialized); This is pretty ugly. What is it used for? Is there any way you can use an API for it instead? > struct bcm_mbox_power *mbox_power; > > static void response_callback(struct mbox_client *cl, void *mssg) > @@ -92,6 +95,7 @@ static int bcm2835_mbox_power_probe(struct platform_device *pdev) > bcm_mbox_set_power(BCM_POWER_USB); > bcm2835_mbox_power_initialized = true; > } > + bcm2835_mbox_power_initialized = true; > > return ret; > } > @@ -99,6 +103,7 @@ static int bcm2835_mbox_power_probe(struct platform_device *pdev) > static int bcm2835_mbox_power_remove(struct platform_device *pdev) > { > bcm_mbox_set_power(0); > + bcm2835_mbox_power_initialized = false; > > mbox_free_channel(mbox_power->chan); > > diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c > index ae095f0..2a4a3a6 100644 > --- a/drivers/usb/dwc2/platform.c > +++ b/drivers/usb/dwc2/platform.c > @@ -136,6 +136,20 @@ static const struct of_device_id dwc2_of_match_table[] = { > }; > MODULE_DEVICE_TABLE(of, dwc2_of_match_table); > > +extern bool bcm2835_mbox_power_initialized; Ughhh, *shudder*. > +bool bcm2835_usb_power_enabled(void) > +{ > +#ifdef CONFIG_BCM2835_MBOX Please don't put #ifdeffery in *.c files. If you have to match on CONFIG_* options, please do so using inlines in a header file somewhere. > + return bcm2835_mbox_power_initialized; > +#else > + /* Assume that somebody else has enabled the power for us > + * (like U-Boot). > + */ > + return true; > +#endif > +} > + > /** > * dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg > * driver > @@ -175,6 +189,12 @@ static int dwc2_driver_probe(struct platform_device *dev) > defparams.dma_desc_enable = 0; > } > > + /* Make sure the platform driver for enabling the power has > + * initialized before we do. > + */ This multi-line comment is unconventional. See: Documentation/CodingStyle > + if (params == ¶ms_bcm2835 && !bcm2835_usb_power_enabled()) > + return -EPROBE_DEFER; Why don't you cut out the middle man and get rid of all of these awful exports? include/linux/platform/bcm2835.h #ifdef CONFIG_BCM2835_MBOX static inline bool bcm2835_is_usb_powered() { return bcm2835_mbox_is_usb_powered(); } #else static inline bool bcm2835_is_usb_powered() { /* * If BCM2835 isn't using its Mailbox(es), the * bootloader is charged with powering up USB. */ return true; } #endif > hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL); > if (!hsotg) > return -ENOMEM; -- 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