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i2c: hix5hd2: add i2c controller driver

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I2C drivers for hix5hd2 soc series, including following chipset
Hi3716CV200, Hi3719CV100, Hi3718CV100, Hi3719MV100, Hi3718MV100.

Signed-off-by: Wei Yan <sledge.yanwei@huawei.com>
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
[wsa: folded dt docs into this patch]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Wei Yan 2014-10-07 09:04:12 +08:00 committed by Wolfram Sang
parent a4ce47f108
commit 15ef27756b
4 changed files with 592 additions and 0 deletions
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24
Documentation/devicetree/bindings/i2c/i2c-hix5hd2.txt Normal file
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@ -0,0 +1,24 @@
I2C for Hisilicon hix5hd2 chipset platform
Required properties:
- compatible: Must be "hisilicon,hix5hd2-i2c"
- reg: physical base address of the controller and length of memory mapped
region.
- interrupts: interrupt number to the cpu.
- #address-cells = <1>;
- #size-cells = <0>;
- clocks: phandles to input clocks.
Optional properties:
- clock-frequency: Desired I2C bus frequency in Hz, otherwise defaults to 100000
- Child nodes conforming to i2c bus binding
Examples:
I2C0@f8b10000 {
compatible = "hisilicon,hix5hd2-i2c";
reg = <0xf8b10000 0x1000>;
interrupts = <0 38 4>;
clocks = <&clock HIX5HD2_I2C0_RST>;
#address-cells = <1>;
#size-cells = <0>;
}

10
drivers/i2c/busses/Kconfig
View File

@ -77,6 +77,16 @@ config I2C_AMD8111
This driver can also be built as a module. If so, the module
will be called i2c-amd8111.
config I2C_HIX5HD2
tristate "Hix5hd2 high-speed I2C driver"
depends on ARCH_HIX5HD2
help
Say Y here to include support for high-speed I2C controller in the
Hisilicon based hix5hd2 SoCs.
This driver can also be built as a module. If so, the module
will be called i2c-hix5hd2.
config I2C_I801
tristate "Intel 82801 (ICH/PCH)"
depends on PCI

1
drivers/i2c/busses/Makefile
View File

@ -48,6 +48,7 @@ obj-$(CONFIG_I2C_EG20T) += i2c-eg20t.o
obj-$(CONFIG_I2C_EXYNOS5) += i2c-exynos5.o
obj-$(CONFIG_I2C_GPIO) += i2c-gpio.o
obj-$(CONFIG_I2C_HIGHLANDER) += i2c-highlander.o
obj-$(CONFIG_I2C_HIX5HD2) += i2c-hix5hd2.o
obj-$(CONFIG_I2C_IBM_IIC) += i2c-ibm_iic.o
obj-$(CONFIG_I2C_IMX) += i2c-imx.o
obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o

557
drivers/i2c/busses/i2c-hix5hd2.c Normal file
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@ -0,0 +1,557 @@
/*
* Copyright (c) 2014 Linaro Ltd.
* Copyright (c) 2014 Hisilicon Limited.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Now only support 7 bit address.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
/* Register Map */
#define HIX5I2C_CTRL 0x00
#define HIX5I2C_COM 0x04
#define HIX5I2C_ICR 0x08
#define HIX5I2C_SR 0x0c
#define HIX5I2C_SCL_H 0x10
#define HIX5I2C_SCL_L 0x14
#define HIX5I2C_TXR 0x18
#define HIX5I2C_RXR 0x1c
/* I2C_CTRL_REG */
#define I2C_ENABLE BIT(8)
#define I2C_UNMASK_TOTAL BIT(7)
#define I2C_UNMASK_START BIT(6)
#define I2C_UNMASK_END BIT(5)
#define I2C_UNMASK_SEND BIT(4)
#define I2C_UNMASK_RECEIVE BIT(3)
#define I2C_UNMASK_ACK BIT(2)
#define I2C_UNMASK_ARBITRATE BIT(1)
#define I2C_UNMASK_OVER BIT(0)
#define I2C_UNMASK_ALL (I2C_UNMASK_ACK | I2C_UNMASK_OVER)
/* I2C_COM_REG */
#define I2C_NO_ACK BIT(4)
#define I2C_START BIT(3)
#define I2C_READ BIT(2)
#define I2C_WRITE BIT(1)
#define I2C_STOP BIT(0)
/* I2C_ICR_REG */
#define I2C_CLEAR_START BIT(6)
#define I2C_CLEAR_END BIT(5)
#define I2C_CLEAR_SEND BIT(4)
#define I2C_CLEAR_RECEIVE BIT(3)
#define I2C_CLEAR_ACK BIT(2)
#define I2C_CLEAR_ARBITRATE BIT(1)
#define I2C_CLEAR_OVER BIT(0)
#define I2C_CLEAR_ALL (I2C_CLEAR_START | I2C_CLEAR_END | \
I2C_CLEAR_SEND | I2C_CLEAR_RECEIVE | \
I2C_CLEAR_ACK | I2C_CLEAR_ARBITRATE | \
I2C_CLEAR_OVER)
/* I2C_SR_REG */
#define I2C_BUSY BIT(7)
#define I2C_START_INTR BIT(6)
#define I2C_END_INTR BIT(5)
#define I2C_SEND_INTR BIT(4)
#define I2C_RECEIVE_INTR BIT(3)
#define I2C_ACK_INTR BIT(2)
#define I2C_ARBITRATE_INTR BIT(1)
#define I2C_OVER_INTR BIT(0)
#define HIX5I2C_MAX_FREQ 400000 /* 400k */
#define HIX5I2C_READ_OPERATION 0x01
enum hix5hd2_i2c_state {
HIX5I2C_STAT_RW_ERR = -1,
HIX5I2C_STAT_INIT,
HIX5I2C_STAT_RW,
HIX5I2C_STAT_SND_STOP,
HIX5I2C_STAT_RW_SUCCESS,
};
struct hix5hd2_i2c_priv {
struct i2c_adapter adap;
struct i2c_msg *msg;
struct completion msg_complete;
unsigned int msg_idx;
unsigned int msg_len;
int stop;
void __iomem *regs;
struct clk *clk;
struct device *dev;
spinlock_t lock; /* IRQ synchronization */
int err;
unsigned int freq;
enum hix5hd2_i2c_state state;
};
static u32 hix5hd2_i2c_clr_pend_irq(struct hix5hd2_i2c_priv *priv)
{
u32 val = readl_relaxed(priv->regs + HIX5I2C_SR);
writel_relaxed(val, priv->regs + HIX5I2C_ICR);
return val;
}
static void hix5hd2_i2c_clr_all_irq(struct hix5hd2_i2c_priv *priv)
{
writel_relaxed(I2C_CLEAR_ALL, priv->regs + HIX5I2C_ICR);
}
static void hix5hd2_i2c_disable_irq(struct hix5hd2_i2c_priv *priv)
{
writel_relaxed(0, priv->regs + HIX5I2C_CTRL);
}
static void hix5hd2_i2c_enable_irq(struct hix5hd2_i2c_priv *priv)
{
writel_relaxed(I2C_ENABLE | I2C_UNMASK_TOTAL | I2C_UNMASK_ALL,
priv->regs + HIX5I2C_CTRL);
}
static void hix5hd2_i2c_drv_setrate(struct hix5hd2_i2c_priv *priv)
{
u32 rate, val;
u32 scl, sysclock;
/* close all i2c interrupt */
val = readl_relaxed(priv->regs + HIX5I2C_CTRL);
writel_relaxed(val & (~I2C_UNMASK_TOTAL), priv->regs + HIX5I2C_CTRL);
rate = priv->freq;
sysclock = clk_get_rate(priv->clk);
scl = (sysclock / (rate * 2)) / 2 - 1;
writel_relaxed(scl, priv->regs + HIX5I2C_SCL_H);
writel_relaxed(scl, priv->regs + HIX5I2C_SCL_L);
/* restore original interrupt*/
writel_relaxed(val, priv->regs + HIX5I2C_CTRL);
dev_dbg(priv->dev, "%s: sysclock=%d, rate=%d, scl=%d\n",
__func__, sysclock, rate, scl);
}
static void hix5hd2_i2c_init(struct hix5hd2_i2c_priv *priv)
{
hix5hd2_i2c_disable_irq(priv);
hix5hd2_i2c_drv_setrate(priv);
hix5hd2_i2c_clr_all_irq(priv);
hix5hd2_i2c_enable_irq(priv);
}
static void hix5hd2_i2c_reset(struct hix5hd2_i2c_priv *priv)
{
clk_disable_unprepare(priv->clk);
msleep(20);
clk_prepare_enable(priv->clk);
hix5hd2_i2c_init(priv);
}
static int hix5hd2_i2c_wait_bus_idle(struct hix5hd2_i2c_priv *priv)
{
unsigned long stop_time;
u32 int_status;
/* wait for 100 milli seconds for the bus to be idle */
stop_time = jiffies + msecs_to_jiffies(100);
do {
int_status = hix5hd2_i2c_clr_pend_irq(priv);
if (!(int_status & I2C_BUSY))
return 0;
usleep_range(50, 200);
} while (time_before(jiffies, stop_time));
return -EBUSY;
}
static void hix5hd2_rw_over(struct hix5hd2_i2c_priv *priv)
{
if (priv->state == HIX5I2C_STAT_SND_STOP)
dev_dbg(priv->dev, "%s: rw and send stop over\n", __func__);
else
dev_dbg(priv->dev, "%s: have not data to send\n", __func__);
priv->state = HIX5I2C_STAT_RW_SUCCESS;
priv->err = 0;
}
static void hix5hd2_rw_handle_stop(struct hix5hd2_i2c_priv *priv)
{
if (priv->stop) {
priv->state = HIX5I2C_STAT_SND_STOP;
writel_relaxed(I2C_STOP, priv->regs + HIX5I2C_COM);
} else {
hix5hd2_rw_over(priv);
}
}
static void hix5hd2_read_handle(struct hix5hd2_i2c_priv *priv)
{
if (priv->msg_len == 1) {
/* the last byte don't need send ACK */
writel_relaxed(I2C_READ | I2C_NO_ACK, priv->regs + HIX5I2C_COM);
} else if (priv->msg_len > 1) {
/* if i2c master receive data will send ACK */
writel_relaxed(I2C_READ, priv->regs + HIX5I2C_COM);
} else {
hix5hd2_rw_handle_stop(priv);
}
}
static void hix5hd2_write_handle(struct hix5hd2_i2c_priv *priv)
{
u8 data;
if (priv->msg_len > 0) {
data = priv->msg->buf[priv->msg_idx++];
writel_relaxed(data, priv->regs + HIX5I2C_TXR);
writel_relaxed(I2C_WRITE, priv->regs + HIX5I2C_COM);
} else {
hix5hd2_rw_handle_stop(priv);
}
}
static int hix5hd2_rw_preprocess(struct hix5hd2_i2c_priv *priv)
{
u8 data;
if (priv->state == HIX5I2C_STAT_INIT) {
priv->state = HIX5I2C_STAT_RW;
} else if (priv->state == HIX5I2C_STAT_RW) {
if (priv->msg->flags & I2C_M_RD) {
data = readl_relaxed(priv->regs + HIX5I2C_RXR);
priv->msg->buf[priv->msg_idx++] = data;
}
priv->msg_len--;
} else {
dev_dbg(priv->dev, "%s: error: priv->state = %d, msg_len = %d\n",
__func__, priv->state, priv->msg_len);
return -EAGAIN;
}
return 0;
}
static irqreturn_t hix5hd2_i2c_irq(int irqno, void *dev_id)
{
struct hix5hd2_i2c_priv *priv = dev_id;
u32 int_status;
int ret;
spin_lock(&priv->lock);
int_status = hix5hd2_i2c_clr_pend_irq(priv);
/* handle error */
if (int_status & I2C_ARBITRATE_INTR) {
/* bus error */
dev_dbg(priv->dev, "ARB bus loss\n");
priv->err = -EAGAIN;
priv->state = HIX5I2C_STAT_RW_ERR;
goto stop;
} else if (int_status & I2C_ACK_INTR) {
/* ack error */
dev_dbg(priv->dev, "No ACK from device\n");
priv->err = -ENXIO;
priv->state = HIX5I2C_STAT_RW_ERR;
goto stop;
}
if (int_status & I2C_OVER_INTR) {
if (priv->msg_len > 0) {
ret = hix5hd2_rw_preprocess(priv);
if (ret) {
priv->err = ret;
priv->state = HIX5I2C_STAT_RW_ERR;
goto stop;
}
if (priv->msg->flags & I2C_M_RD)
hix5hd2_read_handle(priv);
else
hix5hd2_write_handle(priv);
} else {
hix5hd2_rw_over(priv);
}
}
stop:
if ((priv->state == HIX5I2C_STAT_RW_SUCCESS &&
priv->msg->len == priv->msg_idx) ||
(priv->state == HIX5I2C_STAT_RW_ERR)) {
hix5hd2_i2c_disable_irq(priv);
hix5hd2_i2c_clr_pend_irq(priv);
complete(&priv->msg_complete);
}
spin_unlock(&priv->lock);
return IRQ_HANDLED;
}
static void hix5hd2_i2c_message_start(struct hix5hd2_i2c_priv *priv, int stop)
{
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
hix5hd2_i2c_clr_all_irq(priv);
hix5hd2_i2c_enable_irq(priv);
if (priv->msg->flags & I2C_M_RD)
writel_relaxed((priv->msg->addr << 1) | HIX5I2C_READ_OPERATION,
priv->regs + HIX5I2C_TXR);
else
writel_relaxed(priv->msg->addr << 1,
priv->regs + HIX5I2C_TXR);
writel_relaxed(I2C_WRITE | I2C_START, priv->regs + HIX5I2C_COM);
spin_unlock_irqrestore(&priv->lock, flags);
}
static int hix5hd2_i2c_xfer_msg(struct hix5hd2_i2c_priv *priv,
struct i2c_msg *msgs, int stop)
{
unsigned long timeout;
int ret;
priv->msg = msgs;
priv->msg_idx = 0;
priv->msg_len = priv->msg->len;
priv->stop = stop;
priv->err = 0;
priv->state = HIX5I2C_STAT_INIT;
reinit_completion(&priv->msg_complete);
hix5hd2_i2c_message_start(priv, stop);
timeout = wait_for_completion_timeout(&priv->msg_complete,
priv->adap.timeout);
if (timeout == 0) {
priv->state = HIX5I2C_STAT_RW_ERR;
priv->err = -ETIMEDOUT;
dev_warn(priv->dev, "%s timeout=%d\n",
msgs->flags & I2C_M_RD ? "rx" : "tx",
priv->adap.timeout);
}
ret = priv->state;
/*
* If this is the last message to be transfered (stop == 1)
* Then check if the bus can be brought back to idle.
*/
if (priv->state == HIX5I2C_STAT_RW_SUCCESS && stop)
ret = hix5hd2_i2c_wait_bus_idle(priv);
if (ret < 0)
hix5hd2_i2c_reset(priv);
return priv->err;
}
static int hix5hd2_i2c_xfer(struct i2c_adapter *adap,
struct i2c_msg *msgs, int num)
{
struct hix5hd2_i2c_priv *priv = i2c_get_adapdata(adap);
int i, ret, stop;
pm_runtime_get_sync(priv->dev);
for (i = 0; i < num; i++, msgs++) {
stop = (i == num - 1);
ret = hix5hd2_i2c_xfer_msg(priv, msgs, stop);
if (ret < 0)
goto out;
}
if (i == num) {
ret = num;
} else {
/* Only one message, cannot access the device */
if (i == 1)
ret = -EREMOTEIO;
else
ret = i;
dev_warn(priv->dev, "xfer message failed\n");
}
out:
pm_runtime_mark_last_busy(priv->dev);
pm_runtime_put_autosuspend(priv->dev);
return ret;
}
static u32 hix5hd2_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
}
static const struct i2c_algorithm hix5hd2_i2c_algorithm = {
.master_xfer = hix5hd2_i2c_xfer,
.functionality = hix5hd2_i2c_func,
};
static int hix5hd2_i2c_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct hix5hd2_i2c_priv *priv;
struct resource *mem;
unsigned int freq;
int irq, ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
if (of_property_read_u32(np, "clock-frequency", &freq)) {
/* use 100k as default value */
priv->freq = 100000;
} else {
if (freq > HIX5I2C_MAX_FREQ) {
priv->freq = HIX5I2C_MAX_FREQ;
dev_warn(priv->dev, "use max freq %d instead\n",
HIX5I2C_MAX_FREQ);
} else {
priv->freq = freq;
}
}
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(priv->regs))
return PTR_ERR(priv->regs);
irq = platform_get_irq(pdev, 0);
if (irq <= 0) {
dev_err(&pdev->dev, "cannot find HS-I2C IRQ\n");
return irq;
}
priv->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(priv->clk)) {
dev_err(&pdev->dev, "cannot get clock\n");
return PTR_ERR(priv->clk);
}
clk_prepare_enable(priv->clk);
strlcpy(priv->adap.name, "hix5hd2-i2c", sizeof(priv->adap.name));
priv->dev = &pdev->dev;
priv->adap.owner = THIS_MODULE;
priv->adap.algo = &hix5hd2_i2c_algorithm;
priv->adap.retries = 3;
priv->adap.dev.of_node = np;
priv->adap.algo_data = priv;
priv->adap.dev.parent = &pdev->dev;
i2c_set_adapdata(&priv->adap, priv);
platform_set_drvdata(pdev, priv);
spin_lock_init(&priv->lock);
init_completion(&priv->msg_complete);
hix5hd2_i2c_init(priv);
ret = devm_request_irq(&pdev->dev, irq, hix5hd2_i2c_irq,
IRQF_NO_SUSPEND | IRQF_ONESHOT,
dev_name(&pdev->dev), priv);
if (ret != 0) {
dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", irq);
goto err_clk;
}
pm_suspend_ignore_children(&pdev->dev, true);
pm_runtime_set_autosuspend_delay(priv->dev, MSEC_PER_SEC);
pm_runtime_use_autosuspend(priv->dev);
pm_runtime_set_active(priv->dev);
pm_runtime_enable(priv->dev);
ret = i2c_add_adapter(&priv->adap);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add bus to i2c core\n");
goto err_runtime;
}
return ret;
err_runtime:
pm_runtime_disable(priv->dev);
pm_runtime_set_suspended(priv->dev);
err_clk:
clk_disable_unprepare(priv->clk);
return ret;
}
static int hix5hd2_i2c_remove(struct platform_device *pdev)
{
struct hix5hd2_i2c_priv *priv = platform_get_drvdata(pdev);
i2c_del_adapter(&priv->adap);
pm_runtime_disable(priv->dev);
pm_runtime_set_suspended(priv->dev);
return 0;
}
#ifdef CONFIG_PM
static int hix5hd2_i2c_runtime_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct hix5hd2_i2c_priv *priv = platform_get_drvdata(pdev);
clk_disable_unprepare(priv->clk);
return 0;
}
static int hix5hd2_i2c_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct hix5hd2_i2c_priv *priv = platform_get_drvdata(pdev);
clk_prepare_enable(priv->clk);
hix5hd2_i2c_init(priv);
return 0;
}
#endif
static const struct dev_pm_ops hix5hd2_i2c_pm_ops = {
SET_PM_RUNTIME_PM_OPS(hix5hd2_i2c_runtime_suspend,
hix5hd2_i2c_runtime_resume,
NULL)
};
static const struct of_device_id hix5hd2_i2c_match[] = {
{ .compatible = "hisilicon,hix5hd2-i2c" },
{},
};
MODULE_DEVICE_TABLE(of, hix5hd2_i2c_match);
static struct platform_driver hix5hd2_i2c_driver = {
.probe = hix5hd2_i2c_probe,
.remove = hix5hd2_i2c_remove,
.driver = {
.name = "hix5hd2-i2c",
.pm = &hix5hd2_i2c_pm_ops,
.of_match_table = hix5hd2_i2c_match,
},
};
module_platform_driver(hix5hd2_i2c_driver);
MODULE_DESCRIPTION("Hix5hd2 I2C Bus driver");
MODULE_AUTHOR("Wei Yan <sledge.yanwei@huawei.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:i2c-hix5hd2");