On Wed, 10 Nov 2021 21:01:39 +0800
Xiang W [off-list ref] wrote:

? 2021-11-10???? 12:42 +0300?Nikita Shubin???

quoted

From: Nikita Shubin <redacted>

Helper library to keep track of registered I2C adapters,
identified by dts offset, basic send/read functions and
adapter configuration (enable, set dividers, etc...).

Tested-by: Heinrich Schuchardt <redacted>
Reviewed-by: Alexandre Ghiti <redacted>
Tested-by: Alexandre Ghiti <redacted>
Signed-off-by: Nikita Shubin <redacted>  

The i2c bus does not define register-related operations, these
interfaces should be renamed smbus

You are right, it was in first series of patches and i dropped it as
there is no non-smbus version currently. 

So let's resend. I hope this change is trivial enough so i can keep the
tags.

Regards,
Xiang W

quoted

---
v3->v4:
- fixed typo in include/sbi_utils/i2c/i2c.h
- fixed inaccurate configure remove, leaked into patch 0004
---
?include/sbi_utils/i2c/i2c.h | 85
+++++++++++++++++++++++++++++++++++++
?lib/utils/i2c/i2c.c???????? | 75 ++++++++++++++++++++++++++++++++
?lib/utils/i2c/objects.mk??? | 10 +++++
?3 files changed, 170 insertions(+)
?create mode 100644 include/sbi_utils/i2c/i2c.h
?create mode 100644 lib/utils/i2c/i2c.c
?create mode 100644 lib/utils/i2c/objects.mk

diff --git a/include/sbi_utils/i2c/i2c.h

b/include/sbi_utils/i2c/i2c.h
new file mode 100644
index 0000000..79aeeb5

--- /dev/null
+++ b/include/sbi_utils/i2c/i2c.h

@@ -0,0 +1,85 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2021 YADRO
+ *
+ * Authors:
+ *?? Nikita Shubin <n.shubin@yadro.com>
+ */
+
+#ifndef __I2C_H__
+#define __I2C_H__
+
+#include <sbi/sbi_types.h>
+#include <sbi/sbi_list.h>
+
+/** Representation of a I2C adapter */
+struct i2c_adapter {
+???????/** Pointer to I2C driver owning this I2C adapter */
+???????void *driver;
+
+???????/** Unique ID of the I2C adapter assigned by the driver */
+???????int id;
+
+???????/**
+??????? * Send buffer to given address, register
+??????? *
+??????? * @return 0 on success and negative error code on failure
+??????? */
+???????int (*write)(struct i2c_adapter *ia, uint8_t addr, uint8_t

reg,
+?????????????????? uint8_t *buffer, int len);
+
+???????/**
+??????? * Read buffer from given address, register
+??????? *
+??????? * @return 0 on success and negative error code on failure
+??????? */
+???????int (*read)(struct i2c_adapter *ia, uint8_t addr, uint8_t
reg,
+?????????????????? uint8_t *buffer, int len);
+
+???????/** List */
+???????struct sbi_dlist node;
+};
+
+static inline struct i2c_adapter *to_i2c_adapter(struct sbi_dlist
*node)
+{
+???????return container_of(node, struct i2c_adapter, node);
+}
+
+/** Find a registered I2C adapter */
+struct i2c_adapter *i2c_adapter_find(int id);
+
+/** Register I2C adapter */
+int i2c_adapter_add(struct i2c_adapter *ia);
+
+/** Un-register I2C adapter */
+void i2c_adapter_remove(struct i2c_adapter *ia);
+
+/** Send to device on I2C adapter bus */
+int i2c_adapter_write(struct i2c_adapter *ia, uint8_t addr, uint8_t
reg,
+???????????????????? uint8_t *buffer, int len);
+
+/** Read from device on I2C adapter bus */
+int i2c_adapter_read(struct i2c_adapter *ia, uint8_t addr, uint8_t
reg,
+??????????????????? uint8_t *buffer, int len);
+
+static inline int i2c_adapter_reg_write(struct i2c_adapter *ia,
uint8_t addr,
+??????????????????????????????? uint8_t reg, uint8_t val)
+{
+???????return i2c_adapter_write(ia, addr, reg, &val, 1);
+}
+
+static inline int i2c_adapter_reg_read(struct i2c_adapter *ia,
uint8_t addr,
+????????????????????????????????????? uint8_t reg, uint8_t *val)
+{
+???????uint8_t buf;
+???????int ret = i2c_adapter_read(ia, addr, reg, &buf, 1);
+
+???????if (ret)
+???????????????return ret;
+
+???????*val = buf;
+???????return 0;
+}
+
+#endif

diff --git a/lib/utils/i2c/i2c.c b/lib/utils/i2c/i2c.c
new file mode 100644
index 0000000..1f5072c
--- /dev/null
+++ b/lib/utils/i2c/i2c.c

@@ -0,0 +1,75 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2021 YADRO
+ *
+ * Authors:
+ *?? Nikita Shubin <n.shubin@yadro.com>
+ *
+ * derivate: lib/utils/gpio/gpio.c
+ * Authors:
+ *?? Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <sbi/sbi_error.h>
+#include <sbi_utils/i2c/i2c.h>
+
+static SBI_LIST_HEAD(i2c_adapters_list);
+
+struct i2c_adapter *i2c_adapter_find(int id)
+{
+???????struct sbi_dlist *pos;
+
+???????sbi_list_for_each(pos, &(i2c_adapters_list)) {
+???????????????struct i2c_adapter *adap = to_i2c_adapter(pos);
+
+???????????????if (adap->id == id)
+???????????????????????return adap;
+???????}
+
+???????return NULL;
+}
+
+int i2c_adapter_add(struct i2c_adapter *ia)
+{
+???????if (!ia)
+???????????????return SBI_EINVAL;
+
+???????if (i2c_adapter_find(ia->id))
+???????????????return SBI_EALREADY;
+
+???????sbi_list_add(&(ia->node), &(i2c_adapters_list));
+
+???????return 0;
+}
+
+void i2c_adapter_remove(struct i2c_adapter *ia)
+{
+???????if (!ia)
+???????????????return;
+
+???????sbi_list_del(&(ia->node));
+}
+
+int i2c_adapter_write(struct i2c_adapter *ia, uint8_t addr, uint8_t

reg,
+??????????????????? uint8_t *buffer, int len)
+{
+???????if (!ia)
+???????????????return SBI_EINVAL;
+???????if (!ia->write)
+???????????????return SBI_ENOSYS;
+
+???????return ia->write(ia, addr, reg, buffer, len);
+}
+
+
+int i2c_adapter_read(struct i2c_adapter *ia, uint8_t addr, uint8_t
reg,
+??????????????????? uint8_t *buffer, int len)
+{
+???????if (!ia)
+???????????????return SBI_EINVAL;
+???????if (!ia->read)
+???????????????return SBI_ENOSYS;
+
+???????return ia->read(ia, addr, reg, buffer, len);
+}

diff --git a/lib/utils/i2c/objects.mk b/lib/utils/i2c/objects.mk
new file mode 100644
index 0000000..16a70da
--- /dev/null
+++ b/lib/utils/i2c/objects.mk

@@ -0,0 +1,10 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2021 YADRO
+#
+# Authors:
+#?? Nikita Shubin <n.shubin@yadro.com>
+#
+
+libsbiutils-objs-y += i2c/i2c.o

-- 
2.31.1