Since EHCI/OHCI controllers on R-Car Gen3 SoCs are possible to be getting stuck very rarely after a full/low usb device was disconnected. To detect/recover from such a situation, the controllers require a special way which poll the EHCI PORTSC register and changes the OHCI functional state. So, this patch adds a polling timer into the ehci-platform driver, and if the ehci driver detects the issue by the EHCI PORTSC register, the ehci driver removes a companion device (= the OHCI controller) to change the OHCI functional state to USB Reset once. And then, the ehci driver adds the companion device again.
Showing the changes to include/linux (1 of 2 files). Show all
Unified · Split
| @@ -151,7 +151,7 @@ struct ehci_regs { · 150 unmodified lines | |||
| 151 | #define PORT_OWNER (1<<13) /* true: companion hc owns this port */ | 151 | #define PORT_OWNER (1<<13) /* true: companion hc owns this port */ |
| 152 | #define PORT_POWER (1<<12) /* true: has power (see PPC) */ | 152 | #define PORT_POWER (1<<12) /* true: has power (see PPC) */ |
| 153 | #define PORT_USB11(x) (((x)&(3<<10)) == (1<<10)) /* USB 1.1 device */ | 153 | #define PORT_USB11(x) (((x)&(3<<10)) == (1<<10)) /* USB 1.1 device */ |
| 154 | /* 11:10 for detecting lowspeed devices (reset vs release ownership) */ | 154 | #define PORT_LS_MASK (3<<10) /* Link status (SE0, K or J */ |
| 155 | /* 9 reserved */ | 155 | /* 9 reserved */ |
| 156 | #define PORT_LPM (1<<9) /* LPM transaction */ | 156 | #define PORT_LPM (1<<9) /* LPM transaction */ |
| 157 | #define PORT_RESET (1<<8) /* reset port */ | 157 | #define PORT_RESET (1<<8) /* reset port */ |