// SPDX-License-Identifier: GPL-2.0-only /* * drivers/i2c/busses/i2c-tegra-bpmp.c * * Copyright (c) 2016 NVIDIA Corporation. All rights reserved. * * Author: Shardar Shariff Md <[email protected]> */ #include <linux/err.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <soc/tegra/bpmp-abi.h> #include <soc/tegra/bpmp.h> /* * Serialized I2C message header size is 6 bytes and includes address, flags * and length */ #define SERIALI2C_HDR_SIZE … struct tegra_bpmp_i2c { … }; /* * Linux flags are translated to BPMP defined I2C flags that are used in BPMP * firmware I2C driver to avoid any issues in future if Linux I2C flags are * changed. */ static void tegra_bpmp_xlate_flags(u16 flags, u16 *out) { … } /* * The serialized I2C format is simply the following: * [addr little-endian][flags little-endian][len little-endian][data if write] * [addr little-endian][flags little-endian][len little-endian][data if write] * ... * * The flags are translated from Linux kernel representation to seriali2c * representation. Any undefined flag being set causes an error. * * The data is there only for writes. Reads have the data transferred in the * other direction, and thus data is not present. * * See deserialize_i2c documentation for the data format in the other direction. */ static void tegra_bpmp_serialize_i2c_msg(struct tegra_bpmp_i2c *i2c, struct mrq_i2c_request *request, struct i2c_msg *msgs, unsigned int num) { … } /* * The data in the BPMP -> CPU direction is composed of sequential blocks for * those messages that have I2C_M_RD. So, for example, if you have: * * - !I2C_M_RD, len == 5, data == a0 01 02 03 04 * - !I2C_M_RD, len == 1, data == a0 * - I2C_M_RD, len == 2, data == [uninitialized buffer 1] * - !I2C_M_RD, len == 1, data == a2 * - I2C_M_RD, len == 2, data == [uninitialized buffer 2] * * ...then the data in the BPMP -> CPU direction would be 4 bytes total, and * would contain 2 bytes that will go to uninitialized buffer 1, and 2 bytes * that will go to uninitialized buffer 2. */ static int tegra_bpmp_i2c_deserialize(struct tegra_bpmp_i2c *i2c, struct mrq_i2c_response *response, struct i2c_msg *msgs, unsigned int num) { … } static int tegra_bpmp_i2c_msg_len_check(struct i2c_msg *msgs, unsigned int num) { … } static int tegra_bpmp_i2c_msg_xfer(struct tegra_bpmp_i2c *i2c, struct mrq_i2c_request *request, struct mrq_i2c_response *response, bool atomic) { … } static int tegra_bpmp_i2c_xfer_common(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num, bool atomic) { … } static int tegra_bpmp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { … } static int tegra_bpmp_i2c_xfer_atomic(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { … } static u32 tegra_bpmp_i2c_func(struct i2c_adapter *adapter) { … } static const struct i2c_algorithm tegra_bpmp_i2c_algo = …; static int tegra_bpmp_i2c_probe(struct platform_device *pdev) { … } static void tegra_bpmp_i2c_remove(struct platform_device *pdev) { … } static const struct of_device_id tegra_bpmp_i2c_of_match[] = …; MODULE_DEVICE_TABLE(of, tegra_bpmp_i2c_of_match); static struct platform_driver tegra_bpmp_i2c_driver = …; module_platform_driver(…) …; MODULE_DESCRIPTION(…) …; MODULE_AUTHOR(…) …; MODULE_AUTHOR(…) …; MODULE_LICENSE(…) …;
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