usb: dwc3: make HIRD threshold configurable

HIRD threshold should be configurable by different platforms.

From DesignWare databook:
When HIRD_Threshold[4] is set to 1b1 and HIRD value is greater than or
equal to the value in HIRD_Threshold[3:0], dwc3 asserts output signals
utmi_l1_suspend_n to put PHY into Deep Low-Power mode in L1.

When HIRD_Threshold[4] is set to 1b0 or the HIRD value is less than
HIRD_Threshold[3:0], dwc3 asserts output signals utmi_sleep_n on L1.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

4 files changed, 27 insertions, 5 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 3ea55f214439..8ae42b8db02b 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -730,6 +730,7 @@ static int dwc3_probe(struct platform_device *pdev)
         struct dwc3             *dwc;
         u8                      lpm_nyet_threshold;
         u8                      tx_de_emphasis;
+        u8                      hird_threshold;
 
         int                     ret;
 
@@ -791,12 +792,22 @@ static int dwc3_probe(struct platform_device *pdev)
         /* default to -3.5dB de-emphasis */
         tx_de_emphasis = 1;
 
+        /*
+         * default to assert utmi_sleep_n and use maximum allowed HIRD
+         * threshold value of 0b1100
+         */
+        hird_threshold = 12;
+
         if (node) {
                 dwc->maximum_speed = of_usb_get_maximum_speed(node);
                 dwc->has_lpm_erratum = of_property_read_bool(node,
                                 "snps,has-lpm-erratum");
                 of_property_read_u8(node, "snps,lpm-nyet-threshold",
                                 &lpm_nyet_threshold);
+                dwc->is_utmi_l1_suspend = of_property_read_bool(node,
+                                "snps,is-utmi-l1-suspend");
+                of_property_read_u8(node, "snps,hird-threshold",
+                                &hird_threshold);
 
                 dwc->needs_fifo_resize = of_property_read_bool(node,
                                 "tx-fifo-resize");
@@ -832,6 +843,9 @@ static int dwc3_probe(struct platform_device *pdev)
                 dwc->has_lpm_erratum = pdata->has_lpm_erratum;
                 if (pdata->lpm_nyet_threshold)
                         lpm_nyet_threshold = pdata->lpm_nyet_threshold;
+                dwc->is_utmi_l1_suspend = pdata->is_utmi_l1_suspend;
+                if (pdata->hird_threshold)
+                        hird_threshold = pdata->hird_threshold;
 
                 dwc->needs_fifo_resize = pdata->tx_fifo_resize;
                 dwc->dr_mode = pdata->dr_mode;
@@ -859,6 +873,9 @@ static int dwc3_probe(struct platform_device *pdev)
         dwc->lpm_nyet_threshold = lpm_nyet_threshold;
         dwc->tx_de_emphasis = tx_de_emphasis;
 
+        dwc->hird_threshold = hird_threshold
+                | (dwc->is_utmi_l1_suspend << 4);
+
         ret = dwc3_core_get_phy(dwc);
         if (ret)
                 return ret;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index cf86d3022b52..4bb9aa696ede 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -675,12 +675,16 @@ struct dwc3_scratchpad_array {
  * @test_mode: true when we're entering a USB test mode
  * @test_mode_nr: test feature selector
  * @lpm_nyet_threshold: LPM NYET response threshold
+ * @hird_threshold: HIRD threshold
  * @delayed_status: true when gadget driver asks for delayed status
  * @ep0_bounced: true when we used bounce buffer
  * @ep0_expect_in: true when we expect a DATA IN transfer
  * @has_hibernation: true when dwc3 was configured with Hibernation
  * @has_lpm_erratum: true when core was configured with LPM Erratum. Note that
  *                      there's now way for software to detect this in runtime.
+ * @is_utmi_l1_suspend: the core asserts output signal
+ *      0       - utmi_sleep_n
+ *      1       - utmi_l1_suspend_n
  * @is_selfpowered: true when we are selfpowered
  * @is_fpga: true when we are using the FPGA board
  * @needs_fifo_resize: not all users might want fifo resizing, flag it
@@ -797,12 +801,14 @@ struct dwc3 {
         u8                      test_mode;
         u8                      test_mode_nr;
         u8                      lpm_nyet_threshold;
+        u8                      hird_threshold;
 
         unsigned                delayed_status:1;
         unsigned                ep0_bounced:1;
         unsigned                ep0_expect_in:1;
         unsigned                has_hibernation:1;
         unsigned                has_lpm_erratum:1;
+        unsigned                is_utmi_l1_suspend:1;
         unsigned                is_selfpowered:1;
         unsigned                is_fpga:1;
         unsigned                needs_fifo_resize:1;
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 88a065f61150..398c12f5efe3 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2295,11 +2295,7 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
                 reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
 
-                /*
-                 * TODO: This should be configurable. For now using
-                 * maximum allowed HIRD threshold value of 0b1100
-                 */
-                reg |= DWC3_DCTL_HIRD_THRES(12);
+                reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
 
                 /*
                  * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h
index 245300be057a..a3a3b6d5668c 100644
--- a/drivers/usb/dwc3/platform_data.h
+++ b/drivers/usb/dwc3/platform_data.h
@@ -25,6 +25,9 @@ struct dwc3_platform_data {
         enum usb_dr_mode dr_mode;
         bool tx_fifo_resize;
 
+        unsigned is_utmi_l1_suspend:1;
+        u8 hird_threshold;
+
         u8 lpm_nyet_threshold;
 
         unsigned disable_scramble_quirk:1;