usb: musb: dsps: add support for suspend and resume

The dsps platform needs to save save some registers at suspend time and
restore them after resume. This patch adds a struct for these registers,
and also lets the musb core know that the core registers need to be
saved as well.

We also have to explicitly de-assert the port reset upon resume on this
platform, but musb_port_reset() should not be called from glue layers.

Hence, introduce a flag in struct musb_hdrc_config for this.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
index 3f372447166755a2ccb1aaeac2eeb50787650e42..7cfa6e80ad6071b6d63168e31e074870e85105b2 100644 (file)
--- a/drivers/usb/musb/musb_dsps.c
+++ b/drivers/usb/musb/musb_dsps.c
@@ -113,6 +113,19 @@ struct dsps_musb_wrapper {
        u8              poll_seconds;
 };
 
+/*
+ * register shadow for suspend
+ */
+struct dsps_context {
+       u32 control;
+       u32 epintr;
+       u32 coreintr;
+       u32 phy_utmi;
+       u32 mode;
+       u32 tx_mode;
+       u32 rx_mode;
+};
+
 /**
  * DSPS glue structure.
  */
@@ -122,6 +135,8 @@ struct dsps_glue {
        const struct dsps_musb_wrapper *wrp; /* wrapper register offsets */
        struct timer_list timer;        /* otg_workaround timer */
        unsigned long last_timer;    /* last timer data for each instance */
+
+       struct dsps_context context;
 };
 
 static void dsps_musb_try_idle(struct musb *musb, unsigned long timeout)
@@ -559,6 +574,7 @@ static int dsps_create_musb_pdev(struct dsps_glue *glue,
 
        config->num_eps = get_int_prop(dn, "mentor,num-eps");
        config->ram_bits = get_int_prop(dn, "mentor,ram-bits");
+       config->host_port_deassert_reset_at_resume = 1;
        pdata.mode = get_musb_port_mode(dev);
        /* DT keeps this entry in mA, musb expects it as per USB spec */
        pdata.power = get_int_prop(dn, "mentor,power") / 2;
@@ -683,11 +699,52 @@ static const struct of_device_id musb_dsps_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, musb_dsps_of_match);
 
+#ifdef CONFIG_PM
+static int dsps_suspend(struct device *dev)
+{
+       struct dsps_glue *glue = dev_get_drvdata(dev);
+       const struct dsps_musb_wrapper *wrp = glue->wrp;
+       struct musb *musb = platform_get_drvdata(glue->musb);
+       void __iomem *mbase = musb->ctrl_base;
+
+       glue->context.control = dsps_readl(mbase, wrp->control);
+       glue->context.epintr = dsps_readl(mbase, wrp->epintr_set);
+       glue->context.coreintr = dsps_readl(mbase, wrp->coreintr_set);
+       glue->context.phy_utmi = dsps_readl(mbase, wrp->phy_utmi);
+       glue->context.mode = dsps_readl(mbase, wrp->mode);
+       glue->context.tx_mode = dsps_readl(mbase, wrp->tx_mode);
+       glue->context.rx_mode = dsps_readl(mbase, wrp->rx_mode);
+
+       return 0;
+}
+
+static int dsps_resume(struct device *dev)
+{
+       struct dsps_glue *glue = dev_get_drvdata(dev);
+       const struct dsps_musb_wrapper *wrp = glue->wrp;
+       struct musb *musb = platform_get_drvdata(glue->musb);
+       void __iomem *mbase = musb->ctrl_base;
+
+       dsps_writel(mbase, wrp->control, glue->context.control);
+       dsps_writel(mbase, wrp->epintr_set, glue->context.epintr);
+       dsps_writel(mbase, wrp->coreintr_set, glue->context.coreintr);
+       dsps_writel(mbase, wrp->phy_utmi, glue->context.phy_utmi);
+       dsps_writel(mbase, wrp->mode, glue->context.mode);
+       dsps_writel(mbase, wrp->tx_mode, glue->context.tx_mode);
+       dsps_writel(mbase, wrp->rx_mode, glue->context.rx_mode);
+
+       return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(dsps_pm_ops, dsps_suspend, dsps_resume);
+
 static struct platform_driver dsps_usbss_driver = {
        .probe          = dsps_probe,
        .remove         = dsps_remove,
        .driver         = {
                .name   = "musb-dsps",
+               .pm     = &dsps_pm_ops,
                .of_match_table = musb_dsps_of_match,
        },
 };

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 81caf9f4eb1a0119de8b6a68996e5537638b6099..822413899260fd72e6ccb59865abd682b05cd2e3 100644 (file)
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -2464,7 +2464,12 @@ static int musb_bus_suspend(struct usb_hcd *hcd)
 
 static int musb_bus_resume(struct usb_hcd *hcd)
 {
-       /* resuming child port does the work */
+       struct musb *musb = hcd_to_musb(hcd);
+
+       if (musb->config &&
+           musb->config->host_port_deassert_reset_at_resume)
+               musb_port_reset(musb, false);
+
        return 0;
 }
 

diff --git a/drivers/usb/musb/musb_host.h b/drivers/usb/musb/musb_host.h
index e660af90272d701c0d04f3533eb885a4d1464884..7436c24af0ffb6e1c5e932a2780f2e962ebd0288 100644 (file)
--- a/drivers/usb/musb/musb_host.h
+++ b/drivers/usb/musb/musb_host.h
@@ -93,6 +93,7 @@ extern void musb_root_disconnect(struct musb *musb);
 extern void musb_host_resume_root_hub(struct musb *musb);
 extern void musb_host_poke_root_hub(struct musb *musb);
 extern void musb_port_suspend(struct musb *musb, bool do_suspend);
+extern void musb_port_reset(struct musb *musb, bool do_reset);
 #else
 static inline struct musb *hcd_to_musb(struct usb_hcd *hcd)
 {
@@ -123,6 +124,7 @@ static inline void musb_host_resume_root_hub(struct musb *musb)     {}
 static inline void musb_host_poll_rh_status(struct musb *musb) {}
 static inline void musb_host_poke_root_hub(struct musb *musb)  {}
 static inline void musb_port_suspend(struct musb *musb, bool do_suspend) {}
+static inline void musb_port_reset(struct musb *musb)          {}
 #endif
 
 struct usb_hcd;

diff --git a/drivers/usb/musb/musb_virthub.c b/drivers/usb/musb/musb_virthub.c
index e977441401edf6b1ad1f987f269e191f3a9b2105..24e46c0c84b5281c7689ac219ef12402ae032610 100644 (file)
--- a/drivers/usb/musb/musb_virthub.c
+++ b/drivers/usb/musb/musb_virthub.c
@@ -109,7 +109,7 @@ void musb_port_suspend(struct musb *musb, bool do_suspend)
        }
 }
 
-static void musb_port_reset(struct musb *musb, bool do_reset)
+void musb_port_reset(struct musb *musb, bool do_reset)
 {
        u8              power;
        void __iomem    *mbase = musb->mregs;

diff --git a/include/linux/usb/musb.h b/include/linux/usb/musb.h
index eb505250940af073cd1059f82c4e48d773df3acb..a4ee1b582183119557ccc2b59b3d188ad173d8e6 100644 (file)
--- a/include/linux/usb/musb.h
+++ b/include/linux/usb/musb.h
@@ -76,6 +76,9 @@ struct musb_hdrc_config {
        unsigned        dma:1 __deprecated; /* supports DMA */
        unsigned        vendor_req:1 __deprecated; /* vendor registers required */
 
+       /* need to explicitly de-assert the port reset after resume? */
+       unsigned        host_port_deassert_reset_at_resume:1;
+
        u8              num_eps;        /* number of endpoints _with_ ep0 */
        u8              dma_channels __deprecated; /* number of dma channels */
        u8              dyn_fifo_size;  /* dynamic size in bytes */