4.8-stable review patch. If anyone has any objections, please let me know.
------------------ From: Yoshihiro Shimoda <[email protected]> commit b76032396d7958f006bccf5fb2535beb5526837c upstream. Since the controller on R-Car Gen3 doesn't have any status registers to detect initialization (LPSTS.SUSPM = 1) and the initialization needs up to 45 usec, this patch adds wait after the initialization. Otherwise, writing other registers (e.g. INTENB0) will fail. Fixes: de18757e272d ("usb: renesas_usbhs: add R-Car Gen3 power control") Cc: <[email protected]> Signed-off-by: Yoshihiro Shimoda <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/usb/renesas_usbhs/rcar3.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/usb/renesas_usbhs/rcar3.c +++ b/drivers/usb/renesas_usbhs/rcar3.c @@ -9,6 +9,7 @@ * */ +#include <linux/delay.h> #include <linux/io.h> #include "common.h" #include "rcar3.h" @@ -35,10 +36,13 @@ static int usbhs_rcar3_power_ctrl(struct usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 | UGCTRL2_USB0SEL_OTG); - if (enable) + if (enable) { usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM); - else + /* The controller on R-Car Gen3 needs to wait up to 45 usec */ + udelay(45); + } else { usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0); + } return 0; }
