usb: dwc2: embed storage for reg backup in struct dwc2_hsotg

Register backup function can be called from atomic context. Instead
of using atomic memory pool, embed backup storage space in
struct dwc2_hsotg.

Also add a valid flag in each struct as NULL pointer can't be used as
the content validity check any more.

Acked-by: John Youn <johnyoun@synopsys.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c
index e5b546f1152ef0f8c527fb19d776372cb0877f69..c3cc1a78d1e2b3470402f7cae45e4f11aa02dc0a 100644 (file)
--- a/drivers/usb/dwc2/core.c
+++ b/drivers/usb/dwc2/core.c
@@ -72,17 +72,7 @@ static int dwc2_backup_host_registers(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s\n", __func__);
 
        /* Backup Host regs */
-       hr = hsotg->hr_backup;
-       if (!hr) {
-               hr = devm_kzalloc(hsotg->dev, sizeof(*hr), GFP_KERNEL);
-               if (!hr) {
-                       dev_err(hsotg->dev, "%s: can't allocate host regs\n",
-                                       __func__);
-                       return -ENOMEM;
-               }
-
-               hsotg->hr_backup = hr;
-       }
+       hr = &hsotg->hr_backup;
        hr->hcfg = readl(hsotg->regs + HCFG);
        hr->haintmsk = readl(hsotg->regs + HAINTMSK);
        for (i = 0; i < hsotg->core_params->host_channels; ++i)
@@ -90,6 +80,7 @@ static int dwc2_backup_host_registers(struct dwc2_hsotg *hsotg)
 
        hr->hprt0 = readl(hsotg->regs + HPRT0);
        hr->hfir = readl(hsotg->regs + HFIR);
+       hr->valid = true;
 
        return 0;
 }
@@ -109,12 +100,13 @@ static int dwc2_restore_host_registers(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s\n", __func__);
 
        /* Restore host regs */
-       hr = hsotg->hr_backup;
-       if (!hr) {
+       hr = &hsotg->hr_backup;
+       if (!hr->valid) {
                dev_err(hsotg->dev, "%s: no host registers to restore\n",
                                __func__);
                return -EINVAL;
        }
+       hr->valid = false;
 
        writel(hr->hcfg, hsotg->regs + HCFG);
        writel(hr->haintmsk, hsotg->regs + HAINTMSK);
@@ -152,17 +144,7 @@ static int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s\n", __func__);
 
        /* Backup dev regs */
-       dr = hsotg->dr_backup;
-       if (!dr) {
-               dr = devm_kzalloc(hsotg->dev, sizeof(*dr), GFP_KERNEL);
-               if (!dr) {
-                       dev_err(hsotg->dev, "%s: can't allocate device regs\n",
-                                       __func__);
-                       return -ENOMEM;
-               }
-
-               hsotg->dr_backup = dr;
-       }
+       dr = &hsotg->dr_backup;
 
        dr->dcfg = readl(hsotg->regs + DCFG);
        dr->dctl = readl(hsotg->regs + DCTL);
@@ -195,7 +177,7 @@ static int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg)
                dr->doeptsiz[i] = readl(hsotg->regs + DOEPTSIZ(i));
                dr->doepdma[i] = readl(hsotg->regs + DOEPDMA(i));
        }
-
+       dr->valid = true;
        return 0;
 }
 
@@ -215,12 +197,13 @@ static int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s\n", __func__);
 
        /* Restore dev regs */
-       dr = hsotg->dr_backup;
-       if (!dr) {
+       dr = &hsotg->dr_backup;
+       if (!dr->valid) {
                dev_err(hsotg->dev, "%s: no device registers to restore\n",
                                __func__);
                return -EINVAL;
        }
+       dr->valid = false;
 
        writel(dr->dcfg, hsotg->regs + DCFG);
        writel(dr->dctl, hsotg->regs + DCTL);
@@ -268,17 +251,7 @@ static int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg)
        int i;
 
        /* Backup global regs */
-       gr = hsotg->gr_backup;
-       if (!gr) {
-               gr = devm_kzalloc(hsotg->dev, sizeof(*gr), GFP_KERNEL);
-               if (!gr) {
-                       dev_err(hsotg->dev, "%s: can't allocate global regs\n",
-                                       __func__);
-                       return -ENOMEM;
-               }
-
-               hsotg->gr_backup = gr;
-       }
+       gr = &hsotg->gr_backup;
 
        gr->gotgctl = readl(hsotg->regs + GOTGCTL);
        gr->gintmsk = readl(hsotg->regs + GINTMSK);
@@ -291,6 +264,7 @@ static int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg)
        for (i = 0; i < MAX_EPS_CHANNELS; i++)
                gr->dtxfsiz[i] = readl(hsotg->regs + DPTXFSIZN(i));
 
+       gr->valid = true;
        return 0;
 }
 
@@ -309,12 +283,13 @@ static int dwc2_restore_global_registers(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s\n", __func__);
 
        /* Restore global regs */
-       gr = hsotg->gr_backup;
-       if (!gr) {
+       gr = &hsotg->gr_backup;
+       if (!gr->valid) {
                dev_err(hsotg->dev, "%s: no global registers to restore\n",
                                __func__);
                return -EINVAL;
        }
+       gr->valid = false;
 
        writel(0xffffffff, hsotg->regs + GINTSTS);
        writel(gr->gotgctl, hsotg->regs + GOTGCTL);

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 53b8de03f1028c9982e0a403fad2d487ca09bd45..0ed87620941b5606b83f7e628439266ca7831e18 100644 (file)
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -492,6 +492,7 @@ struct dwc2_gregs_backup {
        u32 gdfifocfg;
        u32 dtxfsiz[MAX_EPS_CHANNELS];
        u32 gpwrdn;
+       bool valid;
 };
 
 /**
@@ -521,6 +522,7 @@ struct dwc2_dregs_backup {
        u32 doepctl[MAX_EPS_CHANNELS];
        u32 doeptsiz[MAX_EPS_CHANNELS];
        u32 doepdma[MAX_EPS_CHANNELS];
+       bool valid;
 };
 
 /**
@@ -538,6 +540,7 @@ struct dwc2_hregs_backup {
        u32 hcintmsk[MAX_EPS_CHANNELS];
        u32 hprt0;
        u32 hfir;
+       bool valid;
 };
 
 /**
@@ -705,9 +708,9 @@ struct dwc2_hsotg {
        struct work_struct wf_otg;
        struct timer_list wkp_timer;
        enum dwc2_lx_state lx_state;
-       struct dwc2_gregs_backup *gr_backup;
-       struct dwc2_dregs_backup *dr_backup;
-       struct dwc2_hregs_backup *hr_backup;
+       struct dwc2_gregs_backup gr_backup;
+       struct dwc2_dregs_backup dr_backup;
+       struct dwc2_hregs_backup hr_backup;
 
        struct dentry *debug_root;
        struct debugfs_regset32 *regset;