firmware: tegra: bpmp: Implement suspend/resume support

When returning from a system sleep state, the BPMP driver needs to
reinitialize the IVC channels used to communicate with the BPMP to
restore proper functionality.

Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/firmware/tegra/bpmp.c b/drivers/firmware/tegra/bpmp.c
index 14a456a..a3d5b51 100644 (file)
--- a/drivers/firmware/tegra/bpmp.c
+++ b/drivers/firmware/tegra/bpmp.c
@@ -18,6 +18,7 @@
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
 #include <linux/semaphore.h>
 #include <linux/sched/clock.h>
 
@@ -843,6 +844,23 @@ free_tx:
        return err;
 }
 
+static int __maybe_unused tegra_bpmp_resume(struct device *dev)
+{
+       struct tegra_bpmp *bpmp = dev_get_drvdata(dev);
+       unsigned int i;
+
+       /* reset message channels */
+       tegra_bpmp_channel_reset(bpmp->tx_channel);
+       tegra_bpmp_channel_reset(bpmp->rx_channel);
+
+       for (i = 0; i < bpmp->threaded.count; i++)
+               tegra_bpmp_channel_reset(&bpmp->threaded_channels[i]);
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(tegra_bpmp_pm_ops, NULL, tegra_bpmp_resume);
+
 static const struct tegra_bpmp_soc tegra186_soc = {
        .channels = {
                .cpu_tx = {
@@ -871,6 +889,7 @@ static struct platform_driver tegra_bpmp_driver = {
        .driver = {
                .name = "tegra-bpmp",
                .of_match_table = tegra_bpmp_match,
+               .pm = &tegra_bpmp_pm_ops,
        },
        .probe = tegra_bpmp_probe,
 };