On Wed, Nov 02, 2016 at 03:47:12PM +0900, Yoshihiro Shimoda wrote: > This patch adds sysfs "role" for usb role swap. This parameter can be > read and write. If you use this file as the following, you can swap > the usb role. > > For example: > 1) Connect a usb cable using 2 Salvator-x boards > 2) On A-Device (ID pin is low), you input the following command: > # echo peripheral > /sys/devices/platform/soc/ee080200.usb-phy/role > 3) On B-Device (ID pin is high), you input the following command: > # echo host > /sys/devices/platform/soc/ee080200.usb-phy/role > > Then, the A-device acts as a peripheral and the B-device acts as a host. > Please note that A-Device must input the following command if you > want the board to act as a host again. (even if you disconnect the usb > cable, since id state may be the same, the A-Device keeps to act as > peripheral.) > # echo host > /sys/devices/platform/soc/ee080200.usb-phy/role > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > --- > This patch is based on the latest linux-phy.git / next branch. > (commit id = 7809cd2ce6abd4f431e4b14e6b1276a7cc842ac4) > > Since this patch is related to usb, I added email addresses of Greg, Felipe, > Peter and USB ML as CC. (This patch doesn't use USB OTG FSM though.) > > Changes from v2: > - Modify the sysfs file name to "role", and the argument is "host" or > "peripheral". Peter suggested this. Thank you! > > Changes from v1: > - rebase the latest next branch. > > .../ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 | 15 +++ > drivers/phy/phy-rcar-gen3-usb2.c | 118 ++++++++++++++++++++- > 2 files changed, 132 insertions(+), 1 deletion(-) > create mode 100644 Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > > diff --git a/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > new file mode 100644 > index 0000000..6212697 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > @@ -0,0 +1,15 @@ > +What: /sys/devices/platform/<phy-name>/role > +Date: October 2016 > +KernelVersion: 4.10 > +Contact: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > +Description: > + This file can be read and write. > + The file can show/change the phy mode for role swap of usb. > + > + Write the following strings to change the mode: > + "host" - switching mode from peripheral to host. > + "peripheral" - switching mode from host to peripheral. > + > + Read the file, then it shows the following strings: > + "host" - The mode is host now. > + "peripheral" - The mode is peripheral now. > diff --git a/drivers/phy/phy-rcar-gen3-usb2.c b/drivers/phy/phy-rcar-gen3-usb2.c > index 3d97ead..cfc9956 100644 > --- a/drivers/phy/phy-rcar-gen3-usb2.c > +++ b/drivers/phy/phy-rcar-gen3-usb2.c > @@ -70,6 +70,7 @@ > #define USB2_LINECTRL1_DP_RPD BIT(18) > #define USB2_LINECTRL1_DMRPD_EN BIT(17) > #define USB2_LINECTRL1_DM_RPD BIT(16) > +#define USB2_LINECTRL1_OPMODE_NODRV BIT(6) > > /* ADPCTRL */ > #define USB2_ADPCTRL_OTGSESSVLD BIT(20) > @@ -161,6 +162,43 @@ static void rcar_gen3_init_for_peri(struct rcar_gen3_chan *ch) > schedule_work(&ch->work); > } > > +static void rcar_gen3_init_for_b_host(struct rcar_gen3_chan *ch) > +{ > + void __iomem *usb2_base = ch->base; > + u32 val; > + > + val = readl(usb2_base + USB2_LINECTRL1); > + writel(val | USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1); > + > + rcar_gen3_set_linectrl(ch, 1, 1); > + rcar_gen3_set_host_mode(ch, 1); > + rcar_gen3_enable_vbus_ctrl(ch, 0); > + > + val = readl(usb2_base + USB2_LINECTRL1); > + writel(val & ~USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1); > +} > + > +static void rcar_gen3_init_for_a_peri(struct rcar_gen3_chan *ch) > +{ > + rcar_gen3_set_linectrl(ch, 0, 1); > + rcar_gen3_set_host_mode(ch, 0); > + rcar_gen3_enable_vbus_ctrl(ch, 1); > +} > + > +static void rcar_gen3_init_from_a_peri_to_a_host(struct rcar_gen3_chan *ch) > +{ > + void __iomem *usb2_base = ch->base; > + u32 val; > + > + val = readl(usb2_base + USB2_OBINTEN); > + writel(val & ~USB2_OBINT_BITS, usb2_base + USB2_OBINTEN); > + > + rcar_gen3_enable_vbus_ctrl(ch, 0); > + rcar_gen3_init_for_host(ch); > + > + writel(val | USB2_OBINT_BITS, usb2_base + USB2_OBINTEN); > +} > + > static bool rcar_gen3_check_id(struct rcar_gen3_chan *ch) > { > return !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_IDDIG); > @@ -174,6 +212,65 @@ static void rcar_gen3_device_recognition(struct rcar_gen3_chan *ch) > rcar_gen3_init_for_peri(ch); > } > > +static bool rcar_gen3_is_host(struct rcar_gen3_chan *ch) > +{ > + return !(readl(ch->base + USB2_COMMCTRL) & USB2_COMMCTRL_OTG_PERI); > +} > + > +static ssize_t role_store(struct device *dev, struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + struct rcar_gen3_chan *ch = dev_get_drvdata(dev); > + bool is_b_device, is_host, new_mode_is_host; > + > + if (!ch->has_otg || !ch->phy->init_count) > + return -EIO; > + > + /* > + * is_b_device: true is B-Device. false is A-Device. > + * If {new_mode_}is_host: true is Host mode. false is Peripheral mode. > + */ > + is_b_device = rcar_gen3_check_id(ch); > + is_host = rcar_gen3_is_host(ch); > + if (!strncmp(buf, "host", strlen("host"))) > + new_mode_is_host = true; > + else if (!strncmp(buf, "peripheral", strlen("peripheral"))) > + new_mode_is_host = false; > + else > + return -EINVAL; > + > + /* If current and new mode is the same, this returns the error */ > + if (is_host == new_mode_is_host) > + return -EINVAL; > + > + if (new_mode_is_host) { > + if (!is_b_device && !is_host) /* A-Peripheral */ > + rcar_gen3_init_from_a_peri_to_a_host(ch); > + if (is_b_device && !is_host) /* B-Peripheral */ > + rcar_gen3_init_for_b_host(ch); is_host must be false here > + } else { > + if (!is_b_device && is_host) /* A-Host */ > + rcar_gen3_init_for_a_peri(ch); > + if (is_b_device && is_host) /* B-Host */ > + rcar_gen3_init_for_peri(ch); is_host must be true here > + } > + > + return count; > +} > + How can you handle the case which ID pin is incorrect, eg, ID is 0, but it is peripheral mode at the initialization? -- Best Regards, Peter Chen