Hi
On 11/8/24 9:33 AM, Shyam Sundar S K wrote:
As of now, the I3C subsystem only has ARM-specific initialization, and
there is no corresponding ACPI plumbing present. To address this, ACPI
support needs to be added to both the I3C core and DW driver.
Add support to get the ACPI handle from the _HID probed and parse the apci
object to retrieve the slave information from BIOS.
Based on the acpi object information propogated via BIOS, build the i3c
board information so that the same information can be used across the
driver to handle the slave requests.
Co-developed-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
Signed-off-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
---
Cc: linux-acpi@xxxxxxxxxxxxxxx
drivers/i3c/internals.h | 3 ++
drivers/i3c/master.c | 84 ++++++++++++++++++++++++++++++
drivers/i3c/master/dw-i3c-master.c | 7 +++
include/linux/i3c/master.h | 1 +
4 files changed, 95 insertions(+)
diff --git a/drivers/i3c/internals.h b/drivers/i3c/internals.h
index 433f6088b7ce..178bc0ebe6b6 100644
--- a/drivers/i3c/internals.h
+++ b/drivers/i3c/internals.h
@@ -10,6 +10,9 @@
#include <linux/i3c/master.h>
+#define I3C_GET_PID 0x08
+#define I3C_GET_ADDR 0x7F
+
void i3c_bus_normaluse_lock(struct i3c_bus *bus);
void i3c_bus_normaluse_unlock(struct i3c_bus *bus);
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 6f3eb710a75d..0ceef2aa9161 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -2251,6 +2251,84 @@ static int of_i3c_master_add_dev(struct i3c_master_controller *master,
return ret;
}
+#if IS_ENABLED(CONFIG_ACPI)
+static int i3c_acpi_configure_master(struct i3c_master_controller *master)
+{
+ struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
+ enum i3c_addr_slot_status addrstatus;
+ struct i3c_dev_boardinfo *boardinfo;
+ struct device *dev = &master->dev;
+ struct fwnode_handle *fwnode;
+ struct acpi_device *adev;
+ u32 slv_addr, num_dev;
+ acpi_status status;
+ u64 val;
+
+ status = acpi_evaluate_object_typed(master->ahandle, "_DSD", NULL, &buf, ACPI_TYPE_PACKAGE);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&master->dev, "Error reading _DSD:%s\n", acpi_format_exception(status));
+ return -ENODEV;
+ }
+
+ num_dev = device_get_child_node_count(dev);
+ if (!num_dev) {
+ dev_err(&master->dev, "Error: no child node present\n");
+ return -EINVAL;
+ }
+
I didn't notice earlier these cause host controller registration to fail
and thus regression on platforms where DSDT doesn't have these optional
information for the host controller.
