Add i2cOpenSession, i2csessionSendAuto

nx/include/switch.h

@@ -51,6 +51,7 @@ extern "C" {
 #include "switch/services/hwopus.h"
 #include "switch/services/csrng.h"
 #include "switch/services/lbl.h"
+#include "switch/services/i2c.h"
 #include "switch/services/bpc.h"
 #include "switch/services/pcv.h"
 #include "switch/services/psm.h"

nx/include/switch/services/i2c.h

@@ -0,0 +1,32 @@
+/**
+ * @file i2c.h
+ * @brief I2C service IPC wrapper.
+ * @author SciresM
+ * @copyright libnx Authors
+ */
+#pragma once
+#include "../types.h"
+#include "sm.h"
+
+typedef enum {
+    I2cDevice_AudioCodec = 4,
+} I2cDevice;
+
+typedef struct {
+    Service s;
+} I2cSession;
+
+typedef enum {
+    I2cTransactionOption_Start = (1 << 0),
+    I2cTransactionOption_Stop = (1 << 1),
+
+    I2cTransactionOption_All = I2cTransactionOption_Start | I2cTransactionOption_Stop,
+} I2cTransactionOption;
+
+Result i2cInitialize(void);
+void i2cExit(void);
+
+Result i2cOpenSession(I2cSession *out, I2cDevice dev);
+
+Result i2csessionSendAuto(I2cSession *s, void *buf, size_t size, I2cTransactionOption option);
+void i2csessionClose(I2cSession *s);

nx/source/services/i2c.c

@@ -0,0 +1,112 @@
+#include "types.h"
+#include "result.h"
+#include "arm/atomics.h"
+#include "kernel/ipc.h"
+#include "kernel/detect.h"
+#include "services/i2c.h"
+#include "services/sm.h"
+
+static Service g_i2cSrv;
+static size_t g_i2cSrvPtrBufSize;
+static u64 g_refCnt;
+
+Result i2cInitialize(void) {
+    Result rc = 0;
+    
+    atomicIncrement64(&g_refCnt);
+
+    if (serviceIsActive(&g_i2cSrv))
+        return 0;
+
+    rc = smGetService(&g_i2cSrv, "i2c");
+    
+    if (R_SUCCEEDED(rc)) rc = ipcQueryPointerBufferSize(g_i2cSrv.handle, &g_i2cSrvPtrBufSize);
+
+    if (R_FAILED(rc)) i2cExit();
+
+    return rc;
+}
+
+void i2cExit(void) {
+    if (atomicDecrement64(&g_refCnt) == 0) {
+        g_i2cSrvPtrBufSize = 0;
+        serviceClose(&g_i2cSrv);
+    }
+}
+
+Result i2cOpenSession(I2cSession *out, I2cDevice dev) {
+    IpcCommand c;
+    ipcInitialize(&c);
+
+    struct {
+        u64 magic;
+        u64 cmd_id;
+        u32 device;
+    } *raw;
+
+    raw = serviceIpcPrepareHeader(&g_i2cSrv, &c, sizeof(*raw));
+
+    raw->magic = SFCI_MAGIC;
+    raw->cmd_id = 1;
+    raw->device = dev;
+
+    Result rc = serviceIpcDispatch(&g_i2cSrv);
+
+    if (R_SUCCEEDED(rc)) {
+        IpcParsedCommand r;
+        struct {
+            u64 magic;
+            u64 result;
+        } *resp;
+
+        serviceIpcParse(&g_i2cSrv, &r, sizeof(*resp));
+        resp = r.Raw;
+
+        rc = resp->result;
+
+        if (R_SUCCEEDED(rc)) {
+            serviceCreateSubservice(&out->s, &g_i2cSrv, &r, 0);
+        }
+    }
+
+    return rc;
+}
+
+Result i2csessionSendAuto(I2cSession *s, void *buf, size_t size, I2cTransactionOption option) {
+    IpcCommand c;
+    ipcInitialize(&c);
+    ipcAddSendSmart(&c, g_i2cSrvPtrBufSize, buf, size, 0);
+
+    struct {
+        u64 magic;
+        u64 cmd_id;
+        u32 option;
+    } *raw;
+
+    raw = serviceIpcPrepareHeader(&s->s, &c, sizeof(*raw));
+
+    raw->magic = SFCI_MAGIC;
+    raw->cmd_id = 10;
+    raw->option = option;
+
+    Result rc = serviceIpcDispatch(&s->s);
+
+    if (R_SUCCEEDED(rc)) {
+        IpcParsedCommand r;
+        struct {
+            u64 magic;
+            u64 result;
+        } *resp;
+
+        serviceIpcParse(&s->s, &r, sizeof(*resp));
+        resp = r.Raw;
+
+        rc = resp->result;
+    }
+
+    return rc;
+}
+
+void i2csessionClose(I2cSession *s) {
+    serviceClose(&s->s);
+}