mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
i2c: xiic: Implement power management
Enable power management. This patch enables the clocks before transfer and disables after the transfer. It also adds the clock description. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
parent
33f5ccc343
commit
36ecbcab84
2 changed files with 84 additions and 7 deletions
|
@ -6,14 +6,17 @@ Required properties:
|
||||||
- interrupts : IIC controller unterrupt
|
- interrupts : IIC controller unterrupt
|
||||||
- #address-cells = <1>
|
- #address-cells = <1>
|
||||||
- #size-cells = <0>
|
- #size-cells = <0>
|
||||||
|
- clocks: Input clock specifier. Refer to common clock bindings.
|
||||||
|
|
||||||
Optional properties:
|
Optional properties:
|
||||||
- Child nodes conforming to i2c bus binding
|
- Child nodes conforming to i2c bus binding
|
||||||
|
- clock-names: Input clock name, should be 'pclk'.
|
||||||
|
|
||||||
Example:
|
Example:
|
||||||
|
|
||||||
axi_iic_0: i2c@40800000 {
|
axi_iic_0: i2c@40800000 {
|
||||||
compatible = "xlnx,xps-iic-2.00.a";
|
compatible = "xlnx,xps-iic-2.00.a";
|
||||||
|
clocks = <&clkc 15>;
|
||||||
interrupts = < 1 2 >;
|
interrupts = < 1 2 >;
|
||||||
reg = < 0x40800000 0x10000 >;
|
reg = < 0x40800000 0x10000 >;
|
||||||
|
|
||||||
|
|
|
@ -37,6 +37,8 @@
|
||||||
#include <linux/io.h>
|
#include <linux/io.h>
|
||||||
#include <linux/slab.h>
|
#include <linux/slab.h>
|
||||||
#include <linux/of.h>
|
#include <linux/of.h>
|
||||||
|
#include <linux/clk.h>
|
||||||
|
#include <linux/pm_runtime.h>
|
||||||
|
|
||||||
#define DRIVER_NAME "xiic-i2c"
|
#define DRIVER_NAME "xiic-i2c"
|
||||||
|
|
||||||
|
@ -66,6 +68,7 @@ enum xiic_endian {
|
||||||
* @endianness: big/little-endian byte order
|
* @endianness: big/little-endian byte order
|
||||||
*/
|
*/
|
||||||
struct xiic_i2c {
|
struct xiic_i2c {
|
||||||
|
struct device *dev;
|
||||||
void __iomem *base;
|
void __iomem *base;
|
||||||
wait_queue_head_t wait;
|
wait_queue_head_t wait;
|
||||||
struct i2c_adapter adap;
|
struct i2c_adapter adap;
|
||||||
|
@ -77,6 +80,7 @@ struct xiic_i2c {
|
||||||
struct i2c_msg *rx_msg;
|
struct i2c_msg *rx_msg;
|
||||||
int rx_pos;
|
int rx_pos;
|
||||||
enum xiic_endian endianness;
|
enum xiic_endian endianness;
|
||||||
|
struct clk *clk;
|
||||||
};
|
};
|
||||||
|
|
||||||
|
|
||||||
|
@ -164,6 +168,7 @@ struct xiic_i2c {
|
||||||
|
|
||||||
#define XIIC_RESET_MASK 0xAUL
|
#define XIIC_RESET_MASK 0xAUL
|
||||||
|
|
||||||
|
#define XIIC_PM_TIMEOUT 1000 /* ms */
|
||||||
/*
|
/*
|
||||||
* The following constant is used for the device global interrupt enable
|
* The following constant is used for the device global interrupt enable
|
||||||
* register, to enable all interrupts for the device, this is the only bit
|
* register, to enable all interrupts for the device, this is the only bit
|
||||||
|
@ -676,9 +681,13 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
|
||||||
dev_dbg(adap->dev.parent, "%s entry SR: 0x%x\n", __func__,
|
dev_dbg(adap->dev.parent, "%s entry SR: 0x%x\n", __func__,
|
||||||
xiic_getreg8(i2c, XIIC_SR_REG_OFFSET));
|
xiic_getreg8(i2c, XIIC_SR_REG_OFFSET));
|
||||||
|
|
||||||
|
err = pm_runtime_get_sync(i2c->dev);
|
||||||
|
if (err < 0)
|
||||||
|
return err;
|
||||||
|
|
||||||
err = xiic_busy(i2c);
|
err = xiic_busy(i2c);
|
||||||
if (err)
|
if (err)
|
||||||
return err;
|
goto out;
|
||||||
|
|
||||||
i2c->tx_msg = msgs;
|
i2c->tx_msg = msgs;
|
||||||
i2c->nmsgs = num;
|
i2c->nmsgs = num;
|
||||||
|
@ -686,14 +695,20 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
|
||||||
xiic_start_xfer(i2c);
|
xiic_start_xfer(i2c);
|
||||||
|
|
||||||
if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
|
if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
|
||||||
(i2c->state == STATE_DONE), HZ))
|
(i2c->state == STATE_DONE), HZ)) {
|
||||||
return (i2c->state == STATE_DONE) ? num : -EIO;
|
err = (i2c->state == STATE_DONE) ? num : -EIO;
|
||||||
else {
|
goto out;
|
||||||
|
} else {
|
||||||
i2c->tx_msg = NULL;
|
i2c->tx_msg = NULL;
|
||||||
i2c->rx_msg = NULL;
|
i2c->rx_msg = NULL;
|
||||||
i2c->nmsgs = 0;
|
i2c->nmsgs = 0;
|
||||||
return -ETIMEDOUT;
|
err = -ETIMEDOUT;
|
||||||
|
goto out;
|
||||||
}
|
}
|
||||||
|
out:
|
||||||
|
pm_runtime_mark_last_busy(i2c->dev);
|
||||||
|
pm_runtime_put_autosuspend(i2c->dev);
|
||||||
|
return err;
|
||||||
}
|
}
|
||||||
|
|
||||||
static u32 xiic_func(struct i2c_adapter *adap)
|
static u32 xiic_func(struct i2c_adapter *adap)
|
||||||
|
@ -748,13 +763,28 @@ static int xiic_i2c_probe(struct platform_device *pdev)
|
||||||
mutex_init(&i2c->lock);
|
mutex_init(&i2c->lock);
|
||||||
init_waitqueue_head(&i2c->wait);
|
init_waitqueue_head(&i2c->wait);
|
||||||
|
|
||||||
|
i2c->clk = devm_clk_get(&pdev->dev, NULL);
|
||||||
|
if (IS_ERR(i2c->clk)) {
|
||||||
|
dev_err(&pdev->dev, "input clock not found.\n");
|
||||||
|
return PTR_ERR(i2c->clk);
|
||||||
|
}
|
||||||
|
ret = clk_prepare_enable(i2c->clk);
|
||||||
|
if (ret) {
|
||||||
|
dev_err(&pdev->dev, "Unable to enable clock.\n");
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
i2c->dev = &pdev->dev;
|
||||||
|
pm_runtime_enable(i2c->dev);
|
||||||
|
pm_runtime_set_autosuspend_delay(i2c->dev, XIIC_PM_TIMEOUT);
|
||||||
|
pm_runtime_use_autosuspend(i2c->dev);
|
||||||
|
pm_runtime_set_active(i2c->dev);
|
||||||
ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr,
|
ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr,
|
||||||
xiic_process, IRQF_ONESHOT,
|
xiic_process, IRQF_ONESHOT,
|
||||||
pdev->name, i2c);
|
pdev->name, i2c);
|
||||||
|
|
||||||
if (ret < 0) {
|
if (ret < 0) {
|
||||||
dev_err(&pdev->dev, "Cannot claim IRQ\n");
|
dev_err(&pdev->dev, "Cannot claim IRQ\n");
|
||||||
return ret;
|
goto err_clk_dis;
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
/*
|
||||||
|
@ -776,7 +806,7 @@ static int xiic_i2c_probe(struct platform_device *pdev)
|
||||||
if (ret) {
|
if (ret) {
|
||||||
dev_err(&pdev->dev, "Failed to add adapter\n");
|
dev_err(&pdev->dev, "Failed to add adapter\n");
|
||||||
xiic_deinit(i2c);
|
xiic_deinit(i2c);
|
||||||
return ret;
|
goto err_clk_dis;
|
||||||
}
|
}
|
||||||
|
|
||||||
if (pdata) {
|
if (pdata) {
|
||||||
|
@ -786,16 +816,30 @@ static int xiic_i2c_probe(struct platform_device *pdev)
|
||||||
}
|
}
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
|
|
||||||
|
err_clk_dis:
|
||||||
|
pm_runtime_set_suspended(&pdev->dev);
|
||||||
|
pm_runtime_disable(&pdev->dev);
|
||||||
|
clk_disable_unprepare(i2c->clk);
|
||||||
|
return ret;
|
||||||
}
|
}
|
||||||
|
|
||||||
static int xiic_i2c_remove(struct platform_device *pdev)
|
static int xiic_i2c_remove(struct platform_device *pdev)
|
||||||
{
|
{
|
||||||
struct xiic_i2c *i2c = platform_get_drvdata(pdev);
|
struct xiic_i2c *i2c = platform_get_drvdata(pdev);
|
||||||
|
int ret;
|
||||||
|
|
||||||
/* remove adapter & data */
|
/* remove adapter & data */
|
||||||
i2c_del_adapter(&i2c->adap);
|
i2c_del_adapter(&i2c->adap);
|
||||||
|
|
||||||
|
ret = clk_prepare_enable(i2c->clk);
|
||||||
|
if (ret) {
|
||||||
|
dev_err(&pdev->dev, "Unable to enable clock.\n");
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
xiic_deinit(i2c);
|
xiic_deinit(i2c);
|
||||||
|
clk_disable_unprepare(i2c->clk);
|
||||||
|
pm_runtime_disable(&pdev->dev);
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
@ -808,12 +852,42 @@ static const struct of_device_id xiic_of_match[] = {
|
||||||
MODULE_DEVICE_TABLE(of, xiic_of_match);
|
MODULE_DEVICE_TABLE(of, xiic_of_match);
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
static int __maybe_unused cdns_i2c_runtime_suspend(struct device *dev)
|
||||||
|
{
|
||||||
|
struct platform_device *pdev = to_platform_device(dev);
|
||||||
|
struct xiic_i2c *i2c = platform_get_drvdata(pdev);
|
||||||
|
|
||||||
|
clk_disable(i2c->clk);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int __maybe_unused cdns_i2c_runtime_resume(struct device *dev)
|
||||||
|
{
|
||||||
|
struct platform_device *pdev = to_platform_device(dev);
|
||||||
|
struct xiic_i2c *i2c = platform_get_drvdata(pdev);
|
||||||
|
int ret;
|
||||||
|
|
||||||
|
ret = clk_enable(i2c->clk);
|
||||||
|
if (ret) {
|
||||||
|
dev_err(dev, "Cannot enable clock.\n");
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static const struct dev_pm_ops xiic_dev_pm_ops = {
|
||||||
|
SET_RUNTIME_PM_OPS(cdns_i2c_runtime_suspend,
|
||||||
|
cdns_i2c_runtime_resume, NULL)
|
||||||
|
};
|
||||||
static struct platform_driver xiic_i2c_driver = {
|
static struct platform_driver xiic_i2c_driver = {
|
||||||
.probe = xiic_i2c_probe,
|
.probe = xiic_i2c_probe,
|
||||||
.remove = xiic_i2c_remove,
|
.remove = xiic_i2c_remove,
|
||||||
.driver = {
|
.driver = {
|
||||||
.name = DRIVER_NAME,
|
.name = DRIVER_NAME,
|
||||||
.of_match_table = of_match_ptr(xiic_of_match),
|
.of_match_table = of_match_ptr(xiic_of_match),
|
||||||
|
.pm = &xiic_dev_pm_ops,
|
||||||
},
|
},
|
||||||
};
|
};
|
||||||
|
|
||||||
|
|
Loading…
Reference in a new issue