usb: dwc3: add Tx de-emphasis quirk
This patch adds Tx de-emphasis quirk, and the Tx de-emphasis value is
configurable according to PIPE3 specification.
Value Description
0 -6dB de-emphasis
1 -3.5dB de-emphasis
2 No de-emphasis
3 Reserved
It can be configured on DT or platform data.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index aefb59d..c3dfb19 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -401,6 +401,9 @@
if (dwc->rx_detect_poll_quirk)
reg |= DWC3_GUSB3PIPECTL_RX_DETOPOLL;
+ if (dwc->tx_de_emphasis_quirk)
+ reg |= DWC3_GUSB3PIPECTL_TX_DEEPH(dwc->tx_de_emphasis);
+
dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
mdelay(100);
@@ -720,6 +723,7 @@
struct resource *res;
struct dwc3 *dwc;
u8 lpm_nyet_threshold;
+ u8 tx_de_emphasis;
int ret;
@@ -778,6 +782,9 @@
/* default to highest possible threshold */
lpm_nyet_threshold = 0xff;
+ /* default to -3.5dB de-emphasis */
+ tx_de_emphasis = 1;
+
if (node) {
dwc->maximum_speed = of_usb_get_maximum_speed(node);
dwc->has_lpm_erratum = of_property_read_bool(node,
@@ -805,6 +812,11 @@
"snps,lfps_filter_quirk");
dwc->rx_detect_poll_quirk = of_property_read_bool(node,
"snps,rx_detect_poll_quirk");
+
+ dwc->tx_de_emphasis_quirk = of_property_read_bool(node,
+ "snps,tx_de_emphasis_quirk");
+ of_property_read_u8(node, "snps,tx_de_emphasis",
+ &tx_de_emphasis);
} else if (pdata) {
dwc->maximum_speed = pdata->maximum_speed;
dwc->has_lpm_erratum = pdata->has_lpm_erratum;
@@ -822,6 +834,10 @@
dwc->del_phy_power_chg_quirk = pdata->del_phy_power_chg_quirk;
dwc->lfps_filter_quirk = pdata->lfps_filter_quirk;
dwc->rx_detect_poll_quirk = pdata->rx_detect_poll_quirk;
+
+ dwc->tx_de_emphasis_quirk = pdata->tx_de_emphasis_quirk;
+ if (pdata->tx_de_emphasis)
+ tx_de_emphasis = pdata->tx_de_emphasis;
}
/* default to superspeed if no maximum_speed passed */
@@ -829,6 +845,7 @@
dwc->maximum_speed = USB_SPEED_SUPER;
dwc->lpm_nyet_threshold = lpm_nyet_threshold;
+ dwc->tx_de_emphasis = tx_de_emphasis;
ret = dwc3_core_get_phy(dwc);
if (ret)