OF helper routine scans the SLIMbus DeviceTree, allocates resources,
and creates slim_devices according to the hierarchy.
Signed-off-by: Sagar Dharia <sdharia@xxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/slimbus/bus.txt | 55 ++++++++++++++++++++++
drivers/slimbus/slim-core.c | 57 +++++++++++++++++++++++
2 files changed, 112 insertions(+)
create mode 100644 Documentation/devicetree/bindings/slimbus/bus.txt
diff --git a/Documentation/devicetree/bindings/slimbus/bus.txt b/Documentation/devicetree/bindings/slimbus/bus.txt
new file mode 100644
index 0000000..c5bb54a
--- /dev/null
+++ b/Documentation/devicetree/bindings/slimbus/bus.txt
@@ -0,0 +1,55 @@
+SLIM(Serial Low Power Interchip Media Bus) bus
+
+SLIMbus is a 2-wire bus, and is used to communicate with peripheral
+components like audio-codec.
+
+Controller is a normal device using binding for whatever bus it is
+on (e.g. platform bus).
+Required property for SLIMbus controller node:
+- compatible - name of SLIMbus controller following generic names
+ recommended practice.
+- #address-cells - should be 4 (number of cells required to define
+ 4 fields of the enumeration address for the SLIMbus
+ slave device)
+- #size-cells - should be 0
+
+No other properties are required in the SLIMbus controller bus node.
+
+Child nodes:
+Every SLIMbus controller node can contain zero or more child nodes
+representing slave devices on the bus. Every SLIMbus slave device is
+uniquely determined by the enumeration address containing 4 fields:
+Manufacturer ID, Product code, Device index, and Instance value for
+the device.
+If child node is not present and it is instantiated after device
+discovery (slave device reporting itself present),
+its name will be in this format: "217:60:1:0"
+
+However, the device may need additional non-standard way to power it
+up so that it can start functioning. In that case, child node will
+need to be present as slave of the slimbus-controller device.
+The compatible property will be necessary so that corresponding
+driver can probe and execute the required procedure to make it
+functional.
+
+Required property for SLIMbus child node if it is present:
+- reg - enumeration address fields of the device
+
+- compatible - name of SLIMbus child node using practice typically
+ followed by discoverable buses:
+ "<manufacturer>,<product-model>", "slim"
+
+SLIMbus example for Qualcomm's slimbus manager component:
+
+ slim@28080000 {
+ compatible = "qcom,slim-msm";
+ reg = <0x28080000 0x2000>,
+ interrupts = <0 33 0>;
+ clocks = <&lcc SLIMBUS_SRC>, <&lcc AUDIO_SLIMBUS_CLK>;
+ clock-names = "iface_clk", "core_clk";
+
+ codec@0217.0060.01.00 {
+ compatible = "qcom,wcdv1", "slim";
+ reg = <0x217 0x60 0x1 0x0>;
+ };
+ };
diff --git a/drivers/slimbus/slim-core.c b/drivers/slimbus/slim-core.c
index 6024f74..6aaa08f 100644
--- a/drivers/slimbus/slim-core.c
+++ b/drivers/slimbus/slim-core.c
@@ -18,6 +18,7 @@
#include <linux/idr.h>
#include <linux/pm_runtime.h>
#include <linux/slimbus.h>
+#include <linux/of.h>
static DEFINE_MUTEX(slim_lock);
static DEFINE_IDR(ctrl_idr);
@@ -265,6 +266,61 @@ static LIST_HEAD(board_list);
static LIST_HEAD(slim_ctrl_list);
static DEFINE_MUTEX(board_lock);
+#if IS_ENABLED(CONFIG_OF)
+/* OF helpers for SLIMbus */
+static void of_register_slim_devices(struct slim_controller *ctrl)
+{
+ struct device_node *node;
+
+ if (!ctrl->dev.of_node)
+ return;
+
+ for_each_child_of_node(ctrl->dev.of_node, node) {
+ int ret;
+ u32 ea[4];
+ struct slim_device *slim;
+ char *name;
+
+ ret = of_property_read_u32_array(node, "reg", ea, 4);
+ if (ret) {
+ dev_err(&ctrl->dev, "of_slim: E-addr err:%d\n", ret);
+ continue;
+ }
+ name = kcalloc(SLIMBUS_NAME_SIZE, sizeof(char), GFP_KERNEL);
+ if (!name)
+ return;
+
+ slim = kzalloc(sizeof(struct slim_device), GFP_KERNEL);
+ if (!slim) {
+ kfree(name);
+ return;
+ }
+ slim->dev.of_node = of_node_get(node);
+
+ slim->e_addr.manf_id = (u16)ea[0];
+ slim->e_addr.prod_code = (u16)ea[1];
+ slim->e_addr.dev_index = (u8)ea[2];
+ slim->e_addr.instance = (u8)ea[3];
+
+ ret = of_modalias_node(node, name, SLIMBUS_NAME_SIZE);
+ if (ret < 0) {
+ /* use device address for name, if not specified */
+ snprintf(name, SLIMBUS_NAME_SIZE, "%x:%x:%x:%x",
+ slim->e_addr.manf_id, slim->e_addr.prod_code,
+ slim->e_addr.dev_index, slim->e_addr.instance);
+ }
+ slim->name = name;
+
+ ret = slim_add_device(ctrl, slim);
+ if (ret)
+ dev_err(&ctrl->dev, "of_slim device register err:%d\n",
+ ret);
+ }
+}
+#else
+static void of_register_slim_devices(struct slim_controller *ctrl) { }
+#endif
+
/* If controller is not present, only add to boards list */
static void slim_match_ctrl_to_boardinfo(struct slim_controller *ctrl,
struct slim_boardinfo *bi)
@@ -314,6 +370,7 @@ static void slim_ctrl_add_boarddevs(struct slim_controller *ctrl)
{
struct sbi_boardinfo *bi;
+ of_register_slim_devices(ctrl);
mutex_lock(&board_lock);
list_add_tail(&ctrl->list, &slim_ctrl_list);
list_for_each_entry(bi, &board_list, list)
--
1.8.2.1
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