At very rare cases, the SoF will not send out after resume with
low speed connection. The workaround is do not power down
PWD.RXPWD1PT1 bit during the suspend.
Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
---
drivers/usb/phy/phy-mxs-usb.c | 47 ++++++++++++++++++++++++++++++++++++++++-
1 files changed, 46 insertions(+), 1 deletions(-)
diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
index 542b6ec..5ae4a57 100644
--- a/drivers/usb/phy/phy-mxs-usb.c
+++ b/drivers/usb/phy/phy-mxs-usb.c
@@ -69,6 +69,9 @@
#define ANADIG_USB2_LOOPBACK_SET 0x244
#define ANADIG_USB2_LOOPBACK_CLR 0x248
+#define ANADIG_USB1_MISC 0x1f0
+#define ANADIG_USB2_MISC 0x250
+
#define BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG BIT(12)
#define BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG_SL BIT(11)
@@ -80,6 +83,11 @@
#define BM_ANADIG_USB2_LOOPBACK_UTMI_DIG_TST1 BIT(2)
#define BM_ANADIG_USB2_LOOPBACK_TSTI_TX_EN BIT(5)
+#define BM_ANADIG_USB1_MISC_RX_VPIN_FS BIT(29)
+#define BM_ANADIG_USB1_MISC_RX_VMIN_FS BIT(28)
+#define BM_ANADIG_USB2_MISC_RX_VPIN_FS BIT(29)
+#define BM_ANADIG_USB2_MISC_RX_VMIN_FS BIT(28)
+
#define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
/* Do disconnection between PHY and controller without vbus */
@@ -296,12 +304,49 @@ static void mxs_phy_shutdown(struct usb_phy *phy)
clk_disable_unprepare(mxs_phy->clk);
}
+static bool mxs_phy_is_low_speed_connection(struct mxs_phy *mxs_phy)
+{
+ unsigned int line_state;
+ /* bit definition is the same for all controllers */
+ unsigned int dp_bit = BM_ANADIG_USB1_MISC_RX_VPIN_FS,
+ dm_bit = BM_ANADIG_USB1_MISC_RX_VMIN_FS;
+ unsigned int reg = ANADIG_USB1_MISC;
+
+ /* If the SoCs don't have anatop, quit */
+ if (!mxs_phy->regmap_anatop)
+ return false;
+
+ if (mxs_phy->port_id == 0)
+ reg = ANADIG_USB1_MISC;
+ else if (mxs_phy->port_id == 1)
+ reg = ANADIG_USB2_MISC;
+
+ regmap_read(mxs_phy->regmap_anatop, reg, &line_state);
+
+ if ((line_state & (dp_bit | dm_bit)) == dm_bit)
+ return true;
+ else
+ return false;
+}
+
static int mxs_phy_suspend(struct usb_phy *x, int suspend)
{
struct mxs_phy *mxs_phy = to_mxs_phy(x);
+ bool low_speed_connection, vbus_is_on;
+
+ low_speed_connection = mxs_phy_is_low_speed_connection(mxs_phy);
+ vbus_is_on = mxs_phy_get_vbus_status(mxs_phy);
if (suspend) {
- writel(0xffffffff, x->io_priv + HW_USBPHY_PWD);
+ /*
+ * FIXME: Do not power down RXPWD1PT1 bit for low speed
+ * connect. The low speed connection will have problem at
+ * very rare cases during usb suspend and resume process.
+ */
+ if (low_speed_connection & vbus_is_on)
+ writel(0xfffbffff, x->io_priv + HW_USBPHY_PWD);
+ else
+ writel(0xffffffff, x->io_priv + HW_USBPHY_PWD);
writel(BM_USBPHY_CTRL_CLKGATE,
x->io_priv + HW_USBPHY_CTRL_SET);
clk_disable_unprepare(mxs_phy->clk);
--
1.7.8
--
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