usb: cdns3: gadget.c: Set fast access bit

When the device port is in a low power state [U3/L2/Not Connected],
accesses to usb device registers may take a long time. This could lead to
potential core hang when the controller registers are accessed after the
port is disabled by setting DEVDS field. Setting the fast register access
bit ensures that the PHY clock is keeping up in active state.

Therefore, set fast access bit to ensure the accesses to device registers
are quick even in low power states.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Ravi Gunasekaran <r-gunasekaran@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
This commit is contained in:
Aswath Govindraju 2023-05-12 09:55:59 +05:30 committed by Praneeth Bajjuri
parent 9af8e6313a
commit f2434c3ea2
1 changed files with 4 additions and 0 deletions

View File

@ -2321,6 +2321,9 @@ static void cdns3_gadget_config(struct cdns3_device *priv_dev)
writel(USB_IEN_INIT, &regs->usb_ien);
writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
/* Set the Fast access bit */
writel(PUSB_PWR_FST_REG_ACCESS, &priv_dev->regs->usb_pwr);
cdns3_configure_dmult(priv_dev, NULL);
cdns3_gadget_pullup(&priv_dev->gadget, 1);
@ -2378,6 +2381,7 @@ static int cdns3_gadget_udc_stop(struct usb_gadget *gadget)
/* disable interrupt for device */
writel(0, &priv_dev->regs->usb_ien);
writel(0, &priv_dev->regs->usb_pwr);
writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
return ret;