From a4539a2aa7bde003d4318b1b2e21fd217cc2899f Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Wed, 30 Apr 2014 15:09:57 -0600 Subject: [PATCH] usb: tegra: support device mode A few changes are made to the Tegra EHCI driver so that it can set everything up for device-mode operation on the first USB controller. This can be used in conjunction with ci_udc.c to operate as a USB device. Detailed changes are: * Rename set_host_mode() to set_up_vbus() since that's really what it does. * Modify set_up_vbus() to know whether it's initializing in host or device mode, and: - Skip the external VBUS check in device mode, since external VBUS is expected in this case. - Disable VBUS output in device mode. * Modify init_phy_mux() to know whether it's initializing in host or device mode, and hence skip setting USBMODE_CM_HC (which enables host mode) in device mode. See the comments in that function for why this is safe w.r.t. the ordering requirements of PHY selection. * Modify init_utmi_usb_controller() to force "b session valid" in device mode, since the HW requires this. This is done in UTMI-specific code, since we only support device mode on the first USB controller, and that controller can only talk to a UTMI PHY. * Enhance ehci_hcd_init() to error-check the requested host-/device-mode vs. the dr_mode (dual-role mode) value present in device tree, and the HW configurations which support device mode. * Enhance ehci_hcd_init() not to skip HW initialization when switching between host and device mode on a controller. This requires remembering which mode the last initialization used. Cc: Jim Lin Cc: Stefan Agner Signed-off-by: Stephen Warren --- arch/arm/include/asm/arch-tegra/usb.h | 2 + drivers/usb/host/ehci-tegra.c | 114 +++++++++++++++++++------- 2 files changed, 86 insertions(+), 30 deletions(-) diff --git a/arch/arm/include/asm/arch-tegra/usb.h b/arch/arm/include/asm/arch-tegra/usb.h index ceb7bcd9cf..c817088fa5 100644 --- a/arch/arm/include/asm/arch-tegra/usb.h +++ b/arch/arm/include/asm/arch-tegra/usb.h @@ -349,6 +349,8 @@ struct usb_ctlr { /* USB3_IF_USB_PHY_VBUS_SENSORS_0 */ #define VBUS_VLD_STS (1 << 26) +#define VBUS_B_SESS_VLD_SW_VALUE (1 << 12) +#define VBUS_B_SESS_VLD_SW_EN (1 << 11) /* Setup USB on the board */ int usb_process_devicetree(const void *blob); diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c index 55a546e4d3..33e5ea9ebd 100644 --- a/drivers/usb/host/ehci-tegra.c +++ b/drivers/usb/host/ehci-tegra.c @@ -69,6 +69,7 @@ struct fdt_usb { unsigned enabled:1; /* 1 to enable, 0 to disable */ unsigned has_legacy_mode:1; /* 1 if this port has legacy mode */ unsigned initialized:1; /* has this port already been initialized? */ + enum usb_init_type init_type; enum dr_mode dr_mode; /* dual role mode */ enum periph_id periph_id;/* peripheral id */ struct fdt_gpio_state vbus_gpio; /* GPIO for vbus enable */ @@ -237,29 +238,31 @@ int ehci_get_port_speed(struct ehci_hcor *hcor, uint32_t reg) return PORTSC_PSPD(reg); } -/* Put the port into host mode */ -static void set_host_mode(struct fdt_usb *config) +/* Set up VBUS for host/device mode */ +static void set_up_vbus(struct fdt_usb *config, enum usb_init_type init) { /* - * If we are an OTG port, check if remote host is driving VBus and - * bail out in this case. + * If we are an OTG port initializing in host mode, + * check if remote host is driving VBus and bail out in this case. */ - if (config->dr_mode == DR_MODE_OTG && - (readl(&config->reg->phy_vbus_sensors) & VBUS_VLD_STS)) + if (init == USB_INIT_HOST && + config->dr_mode == DR_MODE_OTG && + (readl(&config->reg->phy_vbus_sensors) & VBUS_VLD_STS)) { + printf("tegrausb: VBUS input active; not enabling as host\n"); return; + } - /* - * If not driving, we set the GPIO to enable VBUS. We assume - * that the pinmux is set up correctly for this. - */ if (fdt_gpio_isvalid(&config->vbus_gpio)) { + int vbus_value; + fdtdec_setup_gpio(&config->vbus_gpio); - gpio_direction_output(config->vbus_gpio.gpio, - (config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ? - 0 : 1); - debug("set_host_mode: GPIO %d %s\n", config->vbus_gpio.gpio, - (config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ? - "low" : "high"); + + vbus_value = (init == USB_INIT_HOST) ^ + !!(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW); + gpio_direction_output(config->vbus_gpio.gpio, vbus_value); + + debug("set_up_vbus: GPIO %d %d\n", config->vbus_gpio.gpio, + vbus_value); } } @@ -294,7 +297,8 @@ static const unsigned *get_pll_timing(void) } /* select the PHY to use with a USB controller */ -static void init_phy_mux(struct fdt_usb *config, uint pts) +static void init_phy_mux(struct fdt_usb *config, uint pts, + enum usb_init_type init) { struct usb_ctlr *usbctlr = config->reg; @@ -309,10 +313,16 @@ static void init_phy_mux(struct fdt_usb *config, uint pts) clrbits_le32(&usbctlr->port_sc1, STS); } #else - /* Set to Host mode after Controller Reset was done */ + /* Set to Host mode (if applicable) after Controller Reset was done */ clrsetbits_le32(&usbctlr->usb_mode, USBMODE_CM_HC, - USBMODE_CM_HC); - /* Select PHY interface after setting host mode */ + (init == USB_INIT_HOST) ? USBMODE_CM_HC : 0); + /* + * Select PHY interface after setting host mode. + * For device mode, the ordering requirement is not an issue, since + * only the first USB controller supports device mode, and that USB + * controller can only talk to a UTMI PHY, so the PHY selection is + * already made at reset time, so this write is a no-op. + */ clrsetbits_le32(&usbctlr->hostpc1_devlc, PTS_MASK, pts << PTS_SHIFT); clrbits_le32(&usbctlr->hostpc1_devlc, STS); @@ -320,9 +330,10 @@ static void init_phy_mux(struct fdt_usb *config, uint pts) } /* set up the UTMI USB controller with the parameters provided */ -static int init_utmi_usb_controller(struct fdt_usb *config) +static int init_utmi_usb_controller(struct fdt_usb *config, + enum usb_init_type init) { - u32 val; + u32 b_sess_valid_mask, val; int loop_count; const unsigned *timing; struct usb_ctlr *usbctlr = config->reg; @@ -340,6 +351,10 @@ static int init_utmi_usb_controller(struct fdt_usb *config) /* Follow the crystal clock disable by >100ns delay */ udelay(1); + b_sess_valid_mask = (VBUS_B_SESS_VLD_SW_VALUE | VBUS_B_SESS_VLD_SW_EN); + clrsetbits_le32(&usbctlr->phy_vbus_sensors, b_sess_valid_mask, + (init == USB_INIT_DEVICE) ? b_sess_valid_mask : 0); + /* * To Use the A Session Valid for cable detection logic, VBUS_WAKEUP * mux must be switched to actually use a_sess_vld threshold. @@ -511,7 +526,7 @@ static int init_utmi_usb_controller(struct fdt_usb *config) clrbits_le32(&usbctlr->icusb_ctrl, IC_ENB1); /* Select UTMI parallel interface */ - init_phy_mux(config, PTS_UTMI); + init_phy_mux(config, PTS_UTMI, init); /* Deassert power down state */ clrbits_le32(&usbctlr->utmip_xcvr_cfg0, UTMIP_FORCE_PD_POWERDOWN | @@ -541,7 +556,8 @@ static int init_utmi_usb_controller(struct fdt_usb *config) #endif /* set up the ULPI USB controller with the parameters provided */ -static int init_ulpi_usb_controller(struct fdt_usb *config) +static int init_ulpi_usb_controller(struct fdt_usb *config, + enum usb_init_type init) { u32 val; int loop_count; @@ -569,7 +585,7 @@ static int init_ulpi_usb_controller(struct fdt_usb *config) ULPI_CLKOUT_PINMUX_BYP | ULPI_OUTPUT_PINMUX_BYP); /* Select ULPI parallel interface */ - init_phy_mux(config, PTS_ULPI); + init_phy_mux(config, PTS_ULPI, init); /* enable ULPI transceiver */ setbits_le32(&usbctlr->susp_ctrl, ULPI_PHY_ENB); @@ -618,7 +634,8 @@ static int init_ulpi_usb_controller(struct fdt_usb *config) return 0; } #else -static int init_ulpi_usb_controller(struct fdt_usb *config) +static int init_ulpi_usb_controller(struct fdt_usb *config, + enum usb_init_type init) { printf("No code to set up ULPI controller, please enable" "CONFIG_USB_ULPI and CONFIG_USB_ULPI_VIEWPORT"); @@ -771,23 +788,60 @@ int ehci_hcd_init(int index, enum usb_init_type init, config = &port[index]; + switch (init) { + case USB_INIT_HOST: + switch (config->dr_mode) { + case DR_MODE_HOST: + case DR_MODE_OTG: + break; + default: + printf("tegrausb: Invalid dr_mode %d for host mode\n", + config->dr_mode); + return -1; + } + break; + case USB_INIT_DEVICE: + if (config->periph_id != PERIPH_ID_USBD) { + printf("tegrausb: Device mode only supported on first USB controller\n"); + return -1; + } + if (!config->utmi) { + printf("tegrausb: Device mode only supported with UTMI PHY\n"); + return -1; + } + switch (config->dr_mode) { + case DR_MODE_DEVICE: + case DR_MODE_OTG: + break; + default: + printf("tegrausb: Invalid dr_mode %d for device mode\n", + config->dr_mode); + return -1; + } + break; + default: + printf("tegrausb: Unknown USB_INIT_* %d\n", init); + return -1; + } + /* skip init, if the port is already initialized */ - if (config->initialized) + if (config->initialized && config->init_type == init) goto success; - if (config->utmi && init_utmi_usb_controller(config)) { + if (config->utmi && init_utmi_usb_controller(config, init)) { printf("tegrausb: Cannot init port %d\n", index); return -1; } - if (config->ulpi && init_ulpi_usb_controller(config)) { + if (config->ulpi && init_ulpi_usb_controller(config, init)) { printf("tegrausb: Cannot init port %d\n", index); return -1; } - set_host_mode(config); + set_up_vbus(config, init); config->initialized = 1; + config->init_type = init; success: usbctlr = config->reg;