[PATCH 09/13] platform/chrome: cros_ec_lpc: Add MKBP events support over ACPI

From: Enric Balletbo i Serra
Date: Fri Mar 17 2017 - 09:58:23 EST


From: Gwendal Grignou <gwendal@xxxxxxxxxxxx>

This patch installs a notify handler to process MKBP events for EC
firmware directing them over ACPI.

Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_lpc.c | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
index 89afad7..eeb187e 100644
--- a/drivers/platform/chrome/cros_ec_lpc.c
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -227,9 +227,20 @@ static int cros_ec_lpc_readmem(struct cros_ec_device *ec, unsigned int offset,
return cnt;
}

+static void cros_ec_lpc_acpi_notify(acpi_handle device, u32 value, void *data)
+{
+ struct cros_ec_device *ec_dev = data;
+
+ if (ec_dev->mkbp_event_supported && cros_ec_get_next_event(ec_dev) > 0)
+ blocking_notifier_call_chain(&ec_dev->event_notifier, 0,
+ ec_dev);
+}
+
static int cros_ec_lpc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
+ struct acpi_device *adev;
+ acpi_status status;
struct cros_ec_device *ec_dev;
u8 buf[2];
int ret;
@@ -277,12 +288,33 @@ static int cros_ec_lpc_probe(struct platform_device *pdev)
return ret;
}

+ /*
+ * Connect a notify handler to process MKBP messages if we have a
+ * companion ACPI device.
+ */
+ adev = ACPI_COMPANION(dev);
+ if (adev) {
+ status = acpi_install_notify_handler(adev->handle,
+ ACPI_ALL_NOTIFY,
+ cros_ec_lpc_acpi_notify,
+ ec_dev);
+ if (ACPI_FAILURE(status))
+ dev_warn(dev, "Failed to register notifier %08x\n",
+ status);
+ }
+
return 0;
}

static int cros_ec_lpc_remove(struct platform_device *pdev)
{
struct cros_ec_device *ec_dev;
+ struct acpi_device *adev;
+
+ adev = ACPI_COMPANION(&pdev->dev);
+ if (adev)
+ acpi_remove_notify_handler(adev->handle, ACPI_ALL_NOTIFY,
+ cros_ec_lpc_acpi_notify);

ec_dev = platform_get_drvdata(pdev);
cros_ec_remove(ec_dev);
--
2.9.3