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 <jilin@nvidia.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Stephen Warren 2014-04-30 15:09:57 -06:00 committed by Marek Vasut
parent 2d34151f75
commit a4539a2aa7
2 changed files with 86 additions and 30 deletions

View file

@ -349,6 +349,8 @@ struct usb_ctlr {
/* USB3_IF_USB_PHY_VBUS_SENSORS_0 */ /* USB3_IF_USB_PHY_VBUS_SENSORS_0 */
#define VBUS_VLD_STS (1 << 26) #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 */ /* Setup USB on the board */
int usb_process_devicetree(const void *blob); int usb_process_devicetree(const void *blob);

View file

@ -69,6 +69,7 @@ struct fdt_usb {
unsigned enabled:1; /* 1 to enable, 0 to disable */ unsigned enabled:1; /* 1 to enable, 0 to disable */
unsigned has_legacy_mode:1; /* 1 if this port has legacy mode */ unsigned has_legacy_mode:1; /* 1 if this port has legacy mode */
unsigned initialized:1; /* has this port already been initialized? */ unsigned initialized:1; /* has this port already been initialized? */
enum usb_init_type init_type;
enum dr_mode dr_mode; /* dual role mode */ enum dr_mode dr_mode; /* dual role mode */
enum periph_id periph_id;/* peripheral id */ enum periph_id periph_id;/* peripheral id */
struct fdt_gpio_state vbus_gpio; /* GPIO for vbus enable */ 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); return PORTSC_PSPD(reg);
} }
/* Put the port into host mode */ /* Set up VBUS for host/device mode */
static void set_host_mode(struct fdt_usb *config) 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 * If we are an OTG port initializing in host mode,
* bail out in this case. * check if remote host is driving VBus and bail out in this case.
*/ */
if (config->dr_mode == DR_MODE_OTG && if (init == USB_INIT_HOST &&
(readl(&config->reg->phy_vbus_sensors) & VBUS_VLD_STS)) 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; 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)) { if (fdt_gpio_isvalid(&config->vbus_gpio)) {
int vbus_value;
fdtdec_setup_gpio(&config->vbus_gpio); fdtdec_setup_gpio(&config->vbus_gpio);
gpio_direction_output(config->vbus_gpio.gpio,
(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ? vbus_value = (init == USB_INIT_HOST) ^
0 : 1); !!(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW);
debug("set_host_mode: GPIO %d %s\n", config->vbus_gpio.gpio, gpio_direction_output(config->vbus_gpio.gpio, vbus_value);
(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ?
"low" : "high"); 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 */ /* 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; 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); clrbits_le32(&usbctlr->port_sc1, STS);
} }
#else #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, clrsetbits_le32(&usbctlr->usb_mode, USBMODE_CM_HC,
USBMODE_CM_HC); (init == USB_INIT_HOST) ? USBMODE_CM_HC : 0);
/* Select PHY interface after setting host mode */ /*
* 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, clrsetbits_le32(&usbctlr->hostpc1_devlc, PTS_MASK,
pts << PTS_SHIFT); pts << PTS_SHIFT);
clrbits_le32(&usbctlr->hostpc1_devlc, STS); 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 */ /* 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; int loop_count;
const unsigned *timing; const unsigned *timing;
struct usb_ctlr *usbctlr = config->reg; 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 */ /* Follow the crystal clock disable by >100ns delay */
udelay(1); 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 * To Use the A Session Valid for cable detection logic, VBUS_WAKEUP
* mux must be switched to actually use a_sess_vld threshold. * 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); clrbits_le32(&usbctlr->icusb_ctrl, IC_ENB1);
/* Select UTMI parallel interface */ /* Select UTMI parallel interface */
init_phy_mux(config, PTS_UTMI); init_phy_mux(config, PTS_UTMI, init);
/* Deassert power down state */ /* Deassert power down state */
clrbits_le32(&usbctlr->utmip_xcvr_cfg0, UTMIP_FORCE_PD_POWERDOWN | 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 #endif
/* set up the ULPI USB controller with the parameters provided */ /* 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; u32 val;
int loop_count; 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); ULPI_CLKOUT_PINMUX_BYP | ULPI_OUTPUT_PINMUX_BYP);
/* Select ULPI parallel interface */ /* Select ULPI parallel interface */
init_phy_mux(config, PTS_ULPI); init_phy_mux(config, PTS_ULPI, init);
/* enable ULPI transceiver */ /* enable ULPI transceiver */
setbits_le32(&usbctlr->susp_ctrl, ULPI_PHY_ENB); setbits_le32(&usbctlr->susp_ctrl, ULPI_PHY_ENB);
@ -618,7 +634,8 @@ static int init_ulpi_usb_controller(struct fdt_usb *config)
return 0; return 0;
} }
#else #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" printf("No code to set up ULPI controller, please enable"
"CONFIG_USB_ULPI and CONFIG_USB_ULPI_VIEWPORT"); "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]; 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 */ /* skip init, if the port is already initialized */
if (config->initialized) if (config->initialized && config->init_type == init)
goto success; 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); printf("tegrausb: Cannot init port %d\n", index);
return -1; 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); printf("tegrausb: Cannot init port %d\n", index);
return -1; return -1;
} }
set_host_mode(config); set_up_vbus(config, init);
config->initialized = 1; config->initialized = 1;
config->init_type = init;
success: success:
usbctlr = config->reg; usbctlr = config->reg;