linux/drivers/mfd/ssbi.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2009-2013, The Linux Foundation. All rights reserved.
 * Copyright (c) 2010, Google Inc.
 *
 * Original authors: Code Aurora Forum
 *
 * Author: Dima Zavin <[email protected]>
 *  - Largely rewritten from original to not be an i2c driver.
 */

#define pr_fmt(fmt) …

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/ssbi.h>

/* SSBI 2.0 controller registers */
#define SSBI2_CMD …
#define SSBI2_RD …
#define SSBI2_STATUS …
#define SSBI2_MODE2 …

/* SSBI_CMD fields */
#define SSBI_CMD_RDWRN …

/* SSBI_STATUS fields */
#define SSBI_STATUS_RD_READY …
#define SSBI_STATUS_READY …
#define SSBI_STATUS_MCHN_BUSY …

/* SSBI_MODE2 fields */
#define SSBI_MODE2_REG_ADDR_15_8_SHFT …
#define SSBI_MODE2_REG_ADDR_15_8_MASK …

#define SET_SSBI_MODE2_REG_ADDR_15_8(MD, AD) …

/* SSBI PMIC Arbiter command registers */
#define SSBI_PA_CMD …
#define SSBI_PA_RD_STATUS …

/* SSBI_PA_CMD fields */
#define SSBI_PA_CMD_RDWRN …
#define SSBI_PA_CMD_ADDR_MASK …

/* SSBI_PA_RD_STATUS fields */
#define SSBI_PA_RD_STATUS_TRANS_DONE …
#define SSBI_PA_RD_STATUS_TRANS_DENIED …

#define SSBI_TIMEOUT_US …

enum ssbi_controller_type { … };

struct ssbi { … };

static inline u32 ssbi_readl(struct ssbi *ssbi, u32 reg)
{ … }

static inline void ssbi_writel(struct ssbi *ssbi, u32 val, u32 reg)
{ … }

/*
 * Via private exchange with one of the original authors, the hardware
 * should generally finish a transaction in about 5us.  The worst
 * case, is when using the arbiter and both other CPUs have just
 * started trying to use the SSBI bus will result in a time of about
 * 20us.  It should never take longer than this.
 *
 * As such, this wait merely spins, with a udelay.
 */
static int ssbi_wait_mask(struct ssbi *ssbi, u32 set_mask, u32 clr_mask)
{ … }

static int
ssbi_read_bytes(struct ssbi *ssbi, u16 addr, u8 *buf, int len)
{ … }

static int
ssbi_write_bytes(struct ssbi *ssbi, u16 addr, const u8 *buf, int len)
{ … }

/*
 * See ssbi_wait_mask for an explanation of the time and the
 * busywait.
 */
static inline int
ssbi_pa_transfer(struct ssbi *ssbi, u32 cmd, u8 *data)
{ … }

static int
ssbi_pa_read_bytes(struct ssbi *ssbi, u16 addr, u8 *buf, int len)
{ … }

static int
ssbi_pa_write_bytes(struct ssbi *ssbi, u16 addr, const u8 *buf, int len)
{ … }

int ssbi_read(struct device *dev, u16 addr, u8 *buf, int len)
{ … }
EXPORT_SYMBOL_GPL(…);

int ssbi_write(struct device *dev, u16 addr, const u8 *buf, int len)
{ … }
EXPORT_SYMBOL_GPL(…);

static int ssbi_probe(struct platform_device *pdev)
{ … }

static const struct of_device_id ssbi_match_table[] = …;
MODULE_DEVICE_TABLE(of, ssbi_match_table);

static struct platform_driver ssbi_driver = …;
module_platform_driver(…) …;

MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;
MODULE_VERSION(…) …;
MODULE_ALIAS(…) …;
MODULE_AUTHOR(…) …;