[PATCH v2 3/7] ACPI / LPSS: do delay for all LPSS devices when D3->D0

Andy Shevchenko
2015-11-26T15:19:27Z

The LPSS DMA device has no context to save, though it requires the same delay
like the rest of LPSS devices when power state is changed from D3 to D0.

Do delay for the DMA device as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/acpi/acpi_lpss.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index e840229..a155dec 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -574,6 +574,17 @@ static void acpi_lpss_restore_ctx(struct device *dev,
{
unsigned int i;

+ for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+ unsigned long offset = i * sizeof(u32);
+
+ __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
+ dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
+ pdata->prv_reg_ctx[i], offset);
+ }
+}
+
+static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
+{
/*
* The following delay is needed or the subsequent write operations may
* fail. The LPSS devices are actually PCI devices and the PCI spec
@@ -586,14 +597,6 @@ static void acpi_lpss_restore_ctx(struct device *dev,
delay = 0;

msleep(delay);
-
- for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
- unsigned long offset = i * sizeof(u32);
-
- __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
- dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
- pdata->prv_reg_ctx[i], offset);
- }
}

#ifdef CONFIG_PM_SLEEP
@@ -621,6 +624,8 @@ static int acpi_lpss_resume_early(struct device *dev)
if (ret)
return ret;

+ acpi_lpss_d3_to_d0_delay(pdata);
+
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_restore_ctx(dev, pdata);

@@ -652,6 +657,8 @@ static int acpi_lpss_runtime_resume(struct device *dev)
if (ret)
return ret;

+ acpi_lpss_d3_to_d0_delay(pdata);
+
if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
acpi_lpss_restore_ctx(dev, pdata);

--
2.6.2