powerpc/85xx: Add lbc suspend support for PM

Power supply for LBC registers is off when system go to deep-sleep state.
We save the values of registers before suspend and restore to registers
after resume.

We removed the last two reservation arrays from struct fsl_lbc_regs for
allocating less memory and minimizing the memcpy size.

Signed-off-by: Jiang Yutang <b14898@freescale.com>
Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 36 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/fsl_lbc.c b/arch/powerpc/sysdev/fsl_lbc.c
index d5c3c90ee698..483126d7b3c0 100644
--- a/arch/powerpc/sysdev/fsl_lbc.c
+++ b/arch/powerpc/sysdev/fsl_lbc.c
@@ -332,6 +332,38 @@ err:
         return ret;
 }
 
+#ifdef CONFIG_SUSPEND
+
+/* save lbc registers */
+static int fsl_lbc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct fsl_lbc_ctrl *ctrl = dev_get_drvdata(&pdev->dev);
+        struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
+
+        ctrl->saved_regs = kmalloc(sizeof(struct fsl_lbc_regs), GFP_KERNEL);
+        if (!ctrl->saved_regs)
+                return -ENOMEM;
+
+        _memcpy_fromio(ctrl->saved_regs, lbc, sizeof(struct fsl_lbc_regs));
+        return 0;
+}
+
+/* restore lbc registers */
+static int fsl_lbc_resume(struct platform_device *pdev)
+{
+        struct fsl_lbc_ctrl *ctrl = dev_get_drvdata(&pdev->dev);
+        struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
+
+        if (ctrl->saved_regs) {
+                _memcpy_toio(lbc, ctrl->saved_regs,
+                                sizeof(struct fsl_lbc_regs));
+                kfree(ctrl->saved_regs);
+                ctrl->saved_regs = NULL;
+        }
+        return 0;
+}
+#endif /* CONFIG_SUSPEND */
+
 static const struct of_device_id fsl_lbc_match[] = {
         { .compatible = "fsl,elbc", },
         { .compatible = "fsl,pq3-localbus", },
@@ -346,6 +378,10 @@ static struct platform_driver fsl_lbc_ctrl_driver = {
                 .of_match_table = fsl_lbc_match,
         },
         .probe = fsl_lbc_ctrl_probe,
+#ifdef CONFIG_SUSPEND
+        .suspend     = fsl_lbc_suspend,
+        .resume      = fsl_lbc_resume,
+#endif
 };
 
 static int __init fsl_lbc_init(void)