usb: dwc3: omap: Add an API to write to dwc mailbox

Add an API in the omap glue layer to write to the mailbox register which
can be used by comparator driver(twl). To pass the detection of the attached
device (signified by VBUS, ID) to the dwc3 core, dwc3 core has to write
to the mailbox regiter.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index f85ae5e6129d..831b75fa4386 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -43,6 +43,7 @@
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/dwc3-omap.h>
+#include <linux/usb/dwc3-omap.h>
 #include <linux/pm_runtime.h>
 #include <linux/dma-mapping.h>
 #include <linux/ioport.h>
@@ -131,6 +132,8 @@ struct dwc3_omap {
         u32                     dma_status:1;
 };
 
+struct dwc3_omap                *_omap;
+
 static inline u32 dwc3_omap_readl(void __iomem *base, u32 offset)
 {
         return readl(base + offset);
@@ -141,6 +144,57 @@ static inline void dwc3_omap_writel(void __iomem *base, u32 offset, u32 value)
         writel(value, base + offset);
 }
 
+void dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
+{
+        u32                     val;
+        struct dwc3_omap        *omap = _omap;
+
+        switch (status) {
+        case OMAP_DWC3_ID_GROUND:
+                dev_dbg(omap->dev, "ID GND\n");
+
+                val = dwc3_omap_readl(omap->base, USBOTGSS_UTMI_OTG_STATUS);
+                val &= ~(USBOTGSS_UTMI_OTG_STATUS_IDDIG
+                                | USBOTGSS_UTMI_OTG_STATUS_VBUSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_SESSEND);
+                val |= USBOTGSS_UTMI_OTG_STATUS_SESSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_POWERPRESENT;
+                dwc3_omap_writel(omap->base, USBOTGSS_UTMI_OTG_STATUS, val);
+                break;
+
+        case OMAP_DWC3_VBUS_VALID:
+                dev_dbg(omap->dev, "VBUS Connect\n");
+
+                val = dwc3_omap_readl(omap->base, USBOTGSS_UTMI_OTG_STATUS);
+                val &= ~USBOTGSS_UTMI_OTG_STATUS_SESSEND;
+                val |= USBOTGSS_UTMI_OTG_STATUS_IDDIG
+                                | USBOTGSS_UTMI_OTG_STATUS_VBUSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_SESSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_POWERPRESENT;
+                dwc3_omap_writel(omap->base, USBOTGSS_UTMI_OTG_STATUS, val);
+                break;
+
+        case OMAP_DWC3_ID_FLOAT:
+        case OMAP_DWC3_VBUS_OFF:
+                dev_dbg(omap->dev, "VBUS Disconnect\n");
+
+                val = dwc3_omap_readl(omap->base, USBOTGSS_UTMI_OTG_STATUS);
+                val &= ~(USBOTGSS_UTMI_OTG_STATUS_SESSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_VBUSVALID
+                                | USBOTGSS_UTMI_OTG_STATUS_POWERPRESENT);
+                val |= USBOTGSS_UTMI_OTG_STATUS_SESSEND
+                                | USBOTGSS_UTMI_OTG_STATUS_IDDIG;
+                dwc3_omap_writel(omap->base, USBOTGSS_UTMI_OTG_STATUS, val);
+                break;
+
+        default:
+                dev_dbg(omap->dev, "ID float\n");
+        }
+
+        return;
+}
+EXPORT_SYMBOL_GPL(dwc3_omap_mailbox);
+
 static int dwc3_omap_register_phys(struct dwc3_omap *omap)
 {
         struct nop_usb_xceiv_platform_data pdata;
@@ -320,6 +374,12 @@ static int dwc3_omap_probe(struct platform_device *pdev)
         omap->irq       = irq;
         omap->base      = base;
 
+        /*
+         * REVISIT if we ever have two instances of the wrapper, we will be
+         * in big trouble
+         */
+        _omap   = omap;
+
         pm_runtime_enable(dev);
         ret = pm_runtime_get_sync(dev);
         if (ret < 0) {