[U-Boot] [PATCH 1/3] usb: tegra: fix PHY selection code

Stephen Warren
2014-04-30T21:09:55Z

From: Stephen Warren <swarren@nvidia.com>

The TRM for Tegra30 and later all state that USBMODE_CM_HC must be set
before writing to hostpc1_devlc to select which PHY to use for a USB
controller. However, neither init_{utmi,ulpi}_usb_controller() do this
today, so the register writes they perform for PHY selection do not
work.

For the UTMI case, this was hacked around in commit 7e44d9320ed4 "ARM:
Tegra: USB: EHCI: Add support for Tegra30/Tegra114" by adding code to
ehci_hcd_init() which sets USBMODE_CM_HC and duplicates the PHY
selection register write. This code doesn't cover the ULPI case, so I
wouldn't be surprised if ULPI doesn't work with the current code, unless
the ordering requirement only ends up being an issue in HW for UTMI not
ULPI.

This patch fixes init_{utmi,ulpi}_usb_controller() to correctly set
USBMODE_CM_HC before selecting the PHY. Now that this works, we can
remove the duplicate UTMI-specific code in ehci_hcd_init(), thus
simplifying that function.

Cc: Jim Lin <jilin@nvidia.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
---
drivers/usb/host/ehci-tegra.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index 38db18e2c9ea..9a9a1277d160 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -496,6 +496,10 @@ static int init_utmi_usb_controller(struct fdt_usb *config)
clrbits_le32(&usbctlr->port_sc1, STS);
}
#else
+ /* Set to Host mode after Controller Reset was done */
+ clrsetbits_le32(&usbctlr->usb_mode, USBMODE_CM_HC,
+ USBMODE_CM_HC);
+ /* Select PHY interface after setting host mode */
clrsetbits_le32(&usbctlr->hostpc1_devlc, PTS_MASK,
PTS_UTMI << PTS_SHIFT);
clrbits_le32(&usbctlr->hostpc1_devlc, STS);
@@ -561,6 +565,10 @@ static int init_ulpi_usb_controller(struct fdt_usb *config)
clrsetbits_le32(&usbctlr->port_sc1, PTS_MASK,
PTS_ULPI << PTS_SHIFT);
#else
+ /* Set to Host mode after Controller Reset was done */
+ clrsetbits_le32(&usbctlr->usb_mode, USBMODE_CM_HC,
+ USBMODE_CM_HC);
+ /* Select PHY interface after setting host mode */
clrsetbits_le32(&usbctlr->hostpc1_devlc, PTS_MASK,
PTS_ULPI << PTS_SHIFT);
#endif
@@ -788,19 +796,6 @@ success:
*hccr = (struct ehci_hccr *)&usbctlr->cap_length;
*hcor = (struct ehci_hcor *)&usbctlr->usb_cmd;

- if (controller->has_hostpc) {
- /* Set to Host mode after Controller Reset was done */
- clrsetbits_le32(&usbctlr->usb_mode, USBMODE_CM_HC,
- USBMODE_CM_HC);
- /* Select UTMI parallel interface after setting host mode */
- if (config->utmi) {
- clrsetbits_le32((char *)&usbctlr->usb_cmd +
- HOSTPC1_DEVLC, PTS_MASK,
- PTS_UTMI << PTS_SHIFT);
- clrbits_le32((char *)&usbctlr->usb_cmd +
- HOSTPC1_DEVLC, STS);
- }
- }
return 0;
}

--
1.8.1.5