summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/sysdev/fsl_pmc.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/sysdev/fsl_pmc.c')
-rw-r--r--arch/powerpc/sysdev/fsl_pmc.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/fsl_pmc.c b/arch/powerpc/sysdev/fsl_pmc.c
new file mode 100644
index 0000000000..9f6dd11c13
--- /dev/null
+++ b/arch/powerpc/sysdev/fsl_pmc.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Suspend/resume support
+ *
+ * Copyright 2009 MontaVista Software, Inc.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/suspend.h>
+#include <linux/delay.h>
+#include <linux/mod_devicetable.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+struct pmc_regs {
+ __be32 devdisr;
+ __be32 devdisr2;
+ __be32 :32;
+ __be32 :32;
+ __be32 pmcsr;
+#define PMCSR_SLP (1 << 17)
+};
+
+static struct device *pmc_dev;
+static struct pmc_regs __iomem *pmc_regs;
+
+static int pmc_suspend_enter(suspend_state_t state)
+{
+ int ret;
+
+ setbits32(&pmc_regs->pmcsr, PMCSR_SLP);
+ /* At this point, the CPU is asleep. */
+
+ /* Upon resume, wait for SLP bit to be clear. */
+ ret = spin_event_timeout((in_be32(&pmc_regs->pmcsr) & PMCSR_SLP) == 0,
+ 10000, 10) ? 0 : -ETIMEDOUT;
+ if (ret)
+ dev_err(pmc_dev, "tired waiting for SLP bit to clear\n");
+ return ret;
+}
+
+static int pmc_suspend_valid(suspend_state_t state)
+{
+ if (state != PM_SUSPEND_STANDBY)
+ return 0;
+ return 1;
+}
+
+static const struct platform_suspend_ops pmc_suspend_ops = {
+ .valid = pmc_suspend_valid,
+ .enter = pmc_suspend_enter,
+};
+
+static int pmc_probe(struct platform_device *ofdev)
+{
+ pmc_regs = of_iomap(ofdev->dev.of_node, 0);
+ if (!pmc_regs)
+ return -ENOMEM;
+
+ pmc_dev = &ofdev->dev;
+ suspend_set_ops(&pmc_suspend_ops);
+ return 0;
+}
+
+static const struct of_device_id pmc_ids[] = {
+ { .compatible = "fsl,mpc8548-pmc", },
+ { .compatible = "fsl,mpc8641d-pmc", },
+ { },
+};
+
+static struct platform_driver pmc_driver = {
+ .driver = {
+ .name = "fsl-pmc",
+ .of_match_table = pmc_ids,
+ },
+ .probe = pmc_probe,
+};
+
+builtin_platform_driver(pmc_driver);