[PATCH v4 14/20] usb: dwc3: add Tx de-emphasis quirk
From: Huang Rui
Date: Thu Oct 30 2014 - 06:11:34 EST
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@xxxxxxx>
---
Documentation/devicetree/bindings/usb/dwc3.txt | 3 +++
drivers/usb/dwc3/core.c | 17 +++++++++++++++++
drivers/usb/dwc3/core.h | 11 +++++++++++
drivers/usb/dwc3/platform_data.h | 3 +++
4 files changed, 34 insertions(+)
diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
index 38bac28..a9e54ae 100644
--- a/Documentation/devicetree/bindings/usb/dwc3.txt
+++ b/Documentation/devicetree/bindings/usb/dwc3.txt
@@ -29,6 +29,9 @@ Optional properties:
- snps,lfps_filter_quirk: when set core will filter LFPS reception.
- snps,rx_detect_poll_quirk: when set core will disable a 400us delay to start
Polling LFPS after RX.Detect.
+ - snps,tx_de_emphasis_quirk: when set core will set Tx de-emphasis value.
+ - snps,tx_de_emphasis: the value driven to the PHY is controlled by the
+ LTSSM during USB3 Compliance mode.
This is usually a subnode to DWC3 glue to which it is connected.
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index e02c3b0..b55fa5b 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -401,6 +401,9 @@ static void dwc3_phy_setup(struct dwc3 *dwc)
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);
@@ -717,6 +720,7 @@ static int dwc3_probe(struct platform_device *pdev)
struct resource *res;
struct dwc3 *dwc;
u8 lpm_nyet_threshold;
+ u8 tx_de_emphasis;
int ret;
@@ -775,6 +779,9 @@ static int dwc3_probe(struct platform_device *pdev)
/* 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,
@@ -802,6 +809,11 @@ static int dwc3_probe(struct platform_device *pdev)
"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;
@@ -819,6 +831,10 @@ static int dwc3_probe(struct platform_device *pdev)
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 */
@@ -826,6 +842,7 @@ static int dwc3_probe(struct platform_device *pdev)
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)
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index eeef976..469ee13 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -185,6 +185,8 @@
#define DWC3_GUSB3PIPECTL_SUSPHY (1 << 17)
#define DWC3_GUSB3PIPECTL_LFPSFILT (1 << 9)
#define DWC3_GUSB3PIPECTL_RX_DETOPOLL (1 << 8)
+#define DWC3_GUSB3PIPECTL_TX_DEEPH_MASK DWC3_GUSB3PIPECTL_TX_DEEPH(3)
+#define DWC3_GUSB3PIPECTL_TX_DEEPH(n) ((n) << 1)
/* Global TX Fifo Size Register */
#define DWC3_GTXFIFOSIZ_TXFDEF(n) ((n) & 0xffff)
@@ -695,6 +697,12 @@ struct dwc3_scratchpad_array {
* @del_phy_power_chg_quirk: set if we enable delay phy power change quirk
* @lfps_filter_quirk: set if we enable LFPS filter quirk
* @rx_detect_poll_quirk: set if we enable rx_detect to polling LFPS quirk
+ * @tx_de_emphasis_quirk: set if we enable Tx de-emphasis quirk
+ * @tx_de_emphasis: Tx de-emphasis value
+ * 0 - -6dB de-emphasis
+ * 1 - -3.5dB de-emphasis
+ * 2 - No de-emphasis
+ * 3 - Reserved
*/
struct dwc3 {
struct usb_ctrlrequest *ctrl_req;
@@ -810,6 +818,9 @@ struct dwc3 {
unsigned del_phy_power_chg_quirk:1;
unsigned lfps_filter_quirk:1;
unsigned rx_detect_poll_quirk:1;
+
+ unsigned tx_de_emphasis_quirk:1;
+ unsigned tx_de_emphasis:2;
};
/* -------------------------------------------------------------------------- */
diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h
index 4a0f06b..e1ab900 100644
--- a/drivers/usb/dwc3/platform_data.h
+++ b/drivers/usb/dwc3/platform_data.h
@@ -36,4 +36,7 @@ struct dwc3_platform_data {
unsigned del_phy_power_chg_quirk:1;
unsigned lfps_filter_quirk:1;
unsigned rx_detect_poll_quirk:1;
+
+ unsigned tx_de_emphasis_quirk:1;
+ unsigned tx_de_emphasis:2;
};
--
1.9.1
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