usb: dwc3: allow forcing a maximum speed

this is mainly for testing. In order to be able
to test if we're enumerating correctly on all
speeds, let that be controlled by a module
parameter.

Signed-off-by: Felipe Balbi <balbi@ti.com>

3 files changed, 18 insertions, 1 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 717ebc9ff941..ca3b01f5fffa 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -59,6 +59,10 @@
 
 #include "debug.h"
 
+static char *maximum_speed = "super";
+module_param(maximum_speed, charp, 0);
+MODULE_PARM_DESC(maximum_speed, "Maximum supported speed.");
+
 /**
  * dwc3_core_soft_reset - Issues core soft reset and PHY reset
  * @dwc: pointer to our context structure
@@ -370,6 +374,17 @@ static int __devinit dwc3_probe(struct platform_device *pdev)
         dwc->dev        = &pdev->dev;
         dwc->irq        = irq;
 
+        if (!strncmp("super", maximum_speed, 5))
+                dwc->maximum_speed = DWC3_DCFG_SUPERSPEED;
+        else if (!strncmp("high", maximum_speed, 4))
+                dwc->maximum_speed = DWC3_DCFG_HIGHSPEED;
+        else if (!strncmp("full", maximum_speed, 4))
+                dwc->maximum_speed = DWC3_DCFG_FULLSPEED1;
+        else if (!strncmp("low", maximum_speed, 3))
+                dwc->maximum_speed = DWC3_DCFG_LOWSPEED;
+        else
+                dwc->maximum_speed = DWC3_DCFG_SUPERSPEED;
+
         pm_runtime_enable(&pdev->dev);
         pm_runtime_get_sync(&pdev->dev);
         pm_runtime_forbid(&pdev->dev);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 29a8e1679e12..b7d56c3a1fbb 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -555,6 +555,7 @@ struct dwc3_hwparams {
  * @regs: base address for our registers
  * @regs_size: address space size
  * @irq: IRQ number
+ * @maximum_speed: maximum speed requested (mainly for testing purposes)
  * @revision: revision register contents
  * @is_selfpowered: true when we are selfpowered
  * @three_stage_setup: set if we perform a three phase setup
@@ -595,6 +596,7 @@ struct dwc3 {
 
         int                     irq;
 
+        u32                     maximum_speed;
         u32                     revision;
 
 #define DWC3_REVISION_173A      0x5533173a
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 46ed15bca19f..807737aec00e 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1183,7 +1183,7 @@ static int dwc3_gadget_start(struct usb_gadget *g,
 
         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
         reg &= ~(DWC3_DCFG_SPEED_MASK);
-        reg |= DWC3_DCFG_SUPERSPEED;
+        reg |= dwc->maximum_speed;
         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
 
         dwc->start_config_issued = false;