+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * I2C driver for PKUnity-v3 SoC
- * Code specific to PKUnity SoC and UniCore ISA
- *
- * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
- * Copyright (C) 2001-2010 Guan Xuetao
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-#include <linux/types.h>
-#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/clk.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-#include <mach/hardware.h>
-
-/*
- * Poll the i2c status register until the specified bit is set.
- * Returns 0 if timed out (100 msec).
- */
-static short poll_status(unsigned long bit)
-{
- int loop_cntr = 1000;
-
- if (bit & I2C_STATUS_TFNF) {
- do {
- udelay(10);
- } while (!(readl(I2C_STATUS) & bit) && (--loop_cntr > 0));
- } else {
- /* RXRDY handler */
- do {
- if (readl(I2C_TAR) == I2C_TAR_EEPROM)
- msleep(20);
- else
- udelay(10);
- } while (!(readl(I2C_RXFLR) & 0xf) && (--loop_cntr > 0));
- }
-
- return (loop_cntr > 0);
-}
-
-static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length)
-{
- int i2c_reg = *buf;
-
- /* Read data */
- while (length--) {
- if (!poll_status(I2C_STATUS_TFNF)) {
- dev_dbg(&adap->dev, "Tx FIFO Not Full timeout\n");
- return -ETIMEDOUT;
- }
-
- /* send addr */
- writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);
-
- /* get ready to next write */
- i2c_reg++;
-
- /* send read CMD */
- writel(I2C_DATACMD_READ, I2C_DATACMD);
-
- /* wait until the Rx FIFO have available */
- if (!poll_status(I2C_STATUS_RFNE)) {
- dev_dbg(&adap->dev, "RXRDY timeout\n");
- return -ETIMEDOUT;
- }
-
- /* read the data to buf */
- *buf = (readl(I2C_DATACMD) & I2C_DATACMD_DAT_MASK);
- buf++;
- }
-
- return 0;
-}
-
-static int xfer_write(struct i2c_adapter *adap, unsigned char *buf, int length)
-{
- int i2c_reg = *buf;
-
- /* Do nothing but storing the reg_num to a static variable */
- if (i2c_reg == -1) {
- printk(KERN_WARNING "Error i2c reg\n");
- return -ETIMEDOUT;
- }
-
- if (length == 1)
- return 0;
-
- buf++;
- length--;
- while (length--) {
- /* send addr */
- writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);
-
- /* send write CMD */
- writel(*buf | I2C_DATACMD_WRITE, I2C_DATACMD);
-
- /* wait until the Rx FIFO have available */
- msleep(20);
-
- /* read the data to buf */
- i2c_reg++;
- buf++;
- }
-
- return 0;
-}
-
-/*
- * Generic i2c master transfer entrypoint.
- *
- */
-static int puv3_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *pmsg,
- int num)
-{
- int i, ret;
- unsigned char swap;
-
- /* Disable i2c */
- writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
-
- /* Set the work mode and speed*/
- writel(I2C_CON_MASTER | I2C_CON_SPEED_STD | I2C_CON_SLAVEDISABLE, I2C_CON);
-
- writel(pmsg->addr, I2C_TAR);
-
- /* Enable i2c */
- writel(I2C_ENABLE_ENABLE, I2C_ENABLE);
-
- dev_dbg(&adap->dev, "puv3_i2c_xfer: processing %d messages:\n", num);
-
- for (i = 0; i < num; i++) {
- dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
- pmsg->flags & I2C_M_RD ? "read" : "writ",
- pmsg->len, pmsg->len > 1 ? "s" : "",
- pmsg->flags & I2C_M_RD ? "from" : "to", pmsg->addr);
-
- if (pmsg->len && pmsg->buf) { /* sanity check */
- if (pmsg->flags & I2C_M_RD)
- ret = xfer_read(adap, pmsg->buf, pmsg->len);
- else
- ret = xfer_write(adap, pmsg->buf, pmsg->len);
-
- if (ret)
- return ret;
-
- }
- dev_dbg(&adap->dev, "transfer complete\n");
- pmsg++; /* next message */
- }
-
- /* XXX: fixup be16_to_cpu in bq27x00_battery.c */
- if (pmsg->addr == I2C_TAR_PWIC) {
- swap = pmsg->buf[0];
- pmsg->buf[0] = pmsg->buf[1];
- pmsg->buf[1] = swap;
- }
-
- return i;
-}
-
-/*
- * Return list of supported functionality.
- */
-static u32 puv3_i2c_func(struct i2c_adapter *adapter)
-{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
-}
-
-static const struct i2c_algorithm puv3_i2c_algorithm = {
- .master_xfer = puv3_i2c_xfer,
- .functionality = puv3_i2c_func,
-};
-
-/*
- * Main initialization routine.
- */
-static int puv3_i2c_probe(struct platform_device *pdev)
-{
- struct i2c_adapter *adapter;
- struct resource *mem;
- int rc;
-
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!mem)
- return -ENODEV;
-
- if (!request_mem_region(mem->start, resource_size(mem), "puv3_i2c"))
- return -EBUSY;
-
- adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
- if (adapter == NULL) {
- dev_err(&pdev->dev, "can't allocate interface!\n");
- rc = -ENOMEM;
- goto fail_nomem;
- }
- snprintf(adapter->name, sizeof(adapter->name), "PUV3-I2C at 0x%08x",
- mem->start);
- adapter->algo = &puv3_i2c_algorithm;
- adapter->class = I2C_CLASS_HWMON;
- adapter->dev.parent = &pdev->dev;
-
- platform_set_drvdata(pdev, adapter);
-
- adapter->nr = pdev->id;
- rc = i2c_add_numbered_adapter(adapter);
- if (rc)
- goto fail_add_adapter;
-
- dev_info(&pdev->dev, "PKUnity v3 i2c bus adapter.\n");
- return 0;
-
-fail_add_adapter:
- kfree(adapter);
-fail_nomem:
- release_mem_region(mem->start, resource_size(mem));
-
- return rc;
-}
-
-static int puv3_i2c_remove(struct platform_device *pdev)
-{
- struct i2c_adapter *adapter = platform_get_drvdata(pdev);
- struct resource *mem;
-
- i2c_del_adapter(adapter);
-
- put_device(&pdev->dev);
-
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(mem->start, resource_size(mem));
-
- return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int puv3_i2c_suspend(struct device *dev)
-{
- int poll_count;
- /* Disable the IIC */
- writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
- for (poll_count = 0; poll_count < 50; poll_count++) {
- if (readl(I2C_ENSTATUS) & I2C_ENSTATUS_ENABLE)
- udelay(25);
- }
-
- return 0;
-}
-
-static SIMPLE_DEV_PM_OPS(puv3_i2c_pm, puv3_i2c_suspend, NULL);
-#define PUV3_I2C_PM (&puv3_i2c_pm)
-
-#else
-#define PUV3_I2C_PM NULL
-#endif
-
-static struct platform_driver puv3_i2c_driver = {
- .probe = puv3_i2c_probe,
- .remove = puv3_i2c_remove,
- .driver = {
- .name = "PKUnity-v3-I2C",
- .pm = PUV3_I2C_PM,
- }
-};
-
-module_platform_driver(puv3_i2c_driver);
-
-MODULE_DESCRIPTION("PKUnity v3 I2C driver");
-MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:puv3_i2c");
projects / mirror_ubuntu-hirsute-kernel.git / commitdiff