Messages in this thread | | | Date | Thu, 23 Jul 2020 11:51:23 -0700 | From | Matthias Kaehlcke <> | Subject | Re: [PATCH v10 1/2] usb: dwc3: qcom: Add interconnect support in dwc3 driver |
| |
Hi Sandeep,
On Thu, Jul 23, 2020 at 11:57:36PM +0530, Sandeep Maheswaram wrote: > Add interconnect support in dwc3-qcom driver to vote for bus > bandwidth. > > This requires for two different paths - from USB to > DDR. The other is from APPS to USB. > > Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org> > Signed-off-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org> > --- > drivers/usb/dwc3/dwc3-qcom.c | 127 ++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 125 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c > index e1e78e9..712efb7 100644 > --- a/drivers/usb/dwc3/dwc3-qcom.c > +++ b/drivers/usb/dwc3/dwc3-qcom.c > @@ -13,6 +13,7 @@ > #include <linux/module.h> > #include <linux/kernel.h> > #include <linux/extcon.h> > +#include <linux/interconnect.h> > #include <linux/of_platform.h> > #include <linux/platform_device.h> > #include <linux/phy/phy.h> > @@ -43,6 +44,14 @@ > #define SDM845_QSCRATCH_SIZE 0x400 > #define SDM845_DWC3_CORE_SIZE 0xcd00 > > +/* Interconnect path bandwidths in MBps */ > +#define USB_MEMORY_AVG_HS_BW MBps_to_icc(240) > +#define USB_MEMORY_PEAK_HS_BW MBps_to_icc(700) > +#define USB_MEMORY_AVG_SS_BW MBps_to_icc(1000) > +#define USB_MEMORY_PEAK_SS_BW MBps_to_icc(2500) > +#define APPS_USB_AVG_BW 0 > +#define APPS_USB_PEAK_BW MBps_to_icc(40) > + > struct dwc3_acpi_pdata { > u32 qscratch_base_offset; > u32 qscratch_base_size; > @@ -76,6 +85,8 @@ struct dwc3_qcom { > enum usb_dr_mode mode; > bool is_suspended; > bool pm_suspended; > + struct icc_path *icc_path_ddr; > + struct icc_path *icc_path_apps; > }; > > static inline void dwc3_qcom_setbits(void __iomem *base, u32 offset, u32 val) > @@ -190,6 +201,103 @@ static int dwc3_qcom_register_extcon(struct dwc3_qcom *qcom) > return 0; > } > > +static int dwc3_qcom_interconnect_enable(struct dwc3_qcom *qcom) > +{ > + int ret; > + > + ret = icc_enable(qcom->icc_path_ddr); > + if (ret) > + return ret; > + > + ret = icc_enable(qcom->icc_path_apps); > + if (ret) > + return icc_disable(qcom->icc_path_ddr);
You are returning the result of icc_disable(), but it should be the previous error. Just do
icc_disable(qcom->icc_path_ddr);
and use the below statement for returning (if not it should be 'return 0').
> + > + return ret; > +} > + > +static int dwc3_qcom_interconnect_disable(struct dwc3_qcom *qcom) > +{ > + int ret; > + > + ret = icc_disable(qcom->icc_path_ddr); > + if (ret) > + return ret; > + > + ret = icc_disable(qcom->icc_path_apps); > + if (ret) > + goto err_reenable_memory_path;
Please make the error handling in _enable() and _disable() symmetrical, either call icc_enable/disable() directly or use a goto in both functions (IMO the goto is not needed in this case, it makes the code more complex rather than simplifying it).
> + > + return 0; > + > + /* Re-enable things in the event of an error */ > +err_reenable_memory_path: > + dwc3_qcom_interconnect_enable(qcom);
Why this function which disables both paths and not just icc_enable(qcom->icc_path_ddr), analogous to dwc3_qcom_interconnect_enable()?
> + > + return ret; > +} > + > +/** > + * dwc3_qcom_interconnect_init() - Get interconnect path handles > + * and set bandwidhth. > + * @qcom: Pointer to the concerned usb core. > + * > + */ > +static int dwc3_qcom_interconnect_init(struct dwc3_qcom *qcom) > +{ > + struct device *dev = qcom->dev; > + int ret; > + > + qcom->icc_path_ddr = of_icc_get(dev, "usb-ddr"); > + if (IS_ERR(qcom->icc_path_ddr)) { > + dev_err(dev, "failed to get usb-ddr path: %ld\n", > + PTR_ERR(qcom->icc_path_ddr)); > + return PTR_ERR(qcom->icc_path_ddr); > + } > + > + qcom->icc_path_apps = of_icc_get(dev, "apps-usb"); > + if (IS_ERR(qcom->icc_path_apps)) { > + dev_err(dev, "failed to get apps-usb path: %ld\n", > + PTR_ERR(qcom->icc_path_apps)); > + return PTR_ERR(qcom->icc_path_apps); > + } > + > + if (usb_get_maximum_speed(&qcom->dwc3->dev) >= USB_SPEED_SUPER || > + usb_get_maximum_speed(&qcom->dwc3->dev) == USB_SPEED_UNKNOWN) > + ret = icc_set_bw(qcom->icc_path_ddr, > + USB_MEMORY_AVG_SS_BW, USB_MEMORY_PEAK_SS_BW); > + else > + ret = icc_set_bw(qcom->icc_path_ddr, > + USB_MEMORY_AVG_HS_BW, USB_MEMORY_PEAK_HS_BW); > + > + if (ret) { > + dev_err(dev, "failed to set bandwidth for usb-ddr path: %d\n", ret); > + return ret; > + } > + > + ret = icc_set_bw(qcom->icc_path_apps, > + APPS_USB_AVG_BW, APPS_USB_PEAK_BW); > +
nit: remove empty line, the call and the if block belong together.
> + if (ret) { > + dev_err(dev, "failed to set bandwidth for apps-usb path: %d\n", ret); > + return ret; > + }
| |