[RFC PATCH 5/9] apple-gmux: Use GMSP acpi method for interrupt clear
From: Orlando Chamberlain
Date: Thu Feb 09 2023 - 23:51:25 EST
This is needed for interrupts to be cleared correctly on MMIO based
gmux's. It is untested if this helps/hinders other gmux types, but I
have seen the GMSP method in the acpi tables of a MacBook with an
indexed gmux.
If this turns out to break support for older gmux's, this can instead
be only done on MMIO gmux's.
There is also a "GMLV" acpi method, and the "GMSP" method can be called
with 1 as its argument, but the purposes of these aren't known and they
don't seem to be needed.
Signed-off-by: Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
---
drivers/platform/x86/apple-gmux.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index 760434a527c1..c605f036ea0b 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -494,8 +494,29 @@ static const struct apple_gmux_config apple_gmux_index = {
* MCP79, on all following generations it's GPIO pin 6 of the Intel PCH.
* The GPE merely signals that an interrupt occurred, the actual type of event
* is identified by reading a gmux register.
+ *
+ * On MMIO gmux's, we also need to call the acpi method GMSP to properly clear
+ * interrupts. TODO: Do other types need this? Does this break other types?
*/
+static int gmux_call_acpi_gmsp(struct apple_gmux_data *gmux_data, int arg)
+{
+ acpi_status status = AE_OK;
+ union acpi_object arg0 = { ACPI_TYPE_INTEGER };
+ struct acpi_object_list arg_list = { 1, &arg0 };
+
+ arg0.integer.value = arg;
+
+ status = acpi_evaluate_object(gmux_data->dhandle, "GMSP", &arg_list, NULL);
+ if (ACPI_FAILURE(status)) {
+ pr_err("GMSP call failed: %s\n",
+ acpi_format_exception(status));
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
{
gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
@@ -519,7 +540,10 @@ static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
/* to clear interrupts write back current status */
status = gmux_interrupt_get_status(gmux_data);
- gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
+ if (status) {
+ gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
+ gmux_call_acpi_gmsp(gmux_data, 0);
+ }
}
static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
--
2.39.1