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path: root/drivers/i2c/busses/i2c-img-scb.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-img-scb.c')
-rw-r--r--drivers/i2c/busses/i2c-img-scb.c104
1 files changed, 81 insertions, 23 deletions
diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c
index eb1d91b986fd..f038858b6c54 100644
--- a/drivers/i2c/busses/i2c-img-scb.c
+++ b/drivers/i2c/busses/i2c-img-scb.c
@@ -82,6 +82,7 @@
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/timer.h>
@@ -280,6 +281,8 @@
#define ISR_COMPLETE(err) (ISR_COMPLETE_M | (ISR_STATUS_M & (err)))
#define ISR_FATAL(err) (ISR_COMPLETE(err) | ISR_FATAL_M)
+#define IMG_I2C_PM_TIMEOUT 1000 /* ms */
+
enum img_i2c_mode {
MODE_INACTIVE,
MODE_RAW,
@@ -408,6 +411,9 @@ struct img_i2c {
unsigned int raw_timeout;
};
+static int img_i2c_runtime_suspend(struct device *dev);
+static int img_i2c_runtime_resume(struct device *dev);
+
static void img_i2c_writel(struct img_i2c *i2c, u32 offset, u32 value)
{
writel(value, i2c->base + offset);
@@ -826,9 +832,9 @@ next_atomic_cmd:
* Timer function to check if something has gone wrong in automatic mode (so we
* don't have to handle so many interrupts just to catch an exception).
*/
-static void img_i2c_check_timer(unsigned long arg)
+static void img_i2c_check_timer(struct timer_list *t)
{
- struct img_i2c *i2c = (struct img_i2c *)arg;
+ struct img_i2c *i2c = from_timer(i2c, t, check_timer);
unsigned long flags;
unsigned int line_status;
@@ -1054,8 +1060,8 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
atomic = true;
}
- ret = clk_prepare_enable(i2c->scb_clk);
- if (ret)
+ ret = pm_runtime_get_sync(adap->dev.parent);
+ if (ret < 0)
return ret;
for (i = 0; i < num; i++) {
@@ -1131,7 +1137,8 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
break;
}
- clk_disable_unprepare(i2c->scb_clk);
+ pm_runtime_mark_last_busy(adap->dev.parent);
+ pm_runtime_put_autosuspend(adap->dev.parent);
return i2c->msg_status ? i2c->msg_status : num;
}
@@ -1149,12 +1156,13 @@ static const struct i2c_algorithm img_i2c_algo = {
static int img_i2c_init(struct img_i2c *i2c)
{
unsigned int clk_khz, bitrate_khz, clk_period, tckh, tckl, tsdh;
- unsigned int i, ret, data, prescale, inc, int_bitrate, filt;
+ unsigned int i, data, prescale, inc, int_bitrate, filt;
struct img_i2c_timings timing;
u32 rev;
+ int ret;
- ret = clk_prepare_enable(i2c->scb_clk);
- if (ret)
+ ret = pm_runtime_get_sync(i2c->adap.dev.parent);
+ if (ret < 0)
return ret;
rev = img_i2c_readl(i2c, SCB_CORE_REV_REG);
@@ -1163,7 +1171,8 @@ static int img_i2c_init(struct img_i2c *i2c)
"Unknown hardware revision (%d.%d.%d.%d)\n",
(rev >> 24) & 0xff, (rev >> 16) & 0xff,
(rev >> 8) & 0xff, rev & 0xff);
- clk_disable_unprepare(i2c->scb_clk);
+ pm_runtime_mark_last_busy(i2c->adap.dev.parent);
+ pm_runtime_put_autosuspend(i2c->adap.dev.parent);
return -EINVAL;
}
@@ -1314,7 +1323,8 @@ static int img_i2c_init(struct img_i2c *i2c)
/* Perform a synchronous sequence to reset the bus */
ret = img_i2c_reset_bus(i2c);
- clk_disable_unprepare(i2c->scb_clk);
+ pm_runtime_mark_last_busy(i2c->adap.dev.parent);
+ pm_runtime_put_autosuspend(i2c->adap.dev.parent);
return ret;
}
@@ -1362,8 +1372,7 @@ static int img_i2c_probe(struct platform_device *pdev)
}
/* Set up the exception check timer */
- setup_timer(&i2c->check_timer, img_i2c_check_timer,
- (unsigned long)i2c);
+ timer_setup(&i2c->check_timer, img_i2c_check_timer, 0);
i2c->bitrate = timings[0].max_bitrate;
if (!of_property_read_u32(node, "clock-frequency", &val))
@@ -1384,22 +1393,30 @@ static int img_i2c_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, i2c);
- ret = clk_prepare_enable(i2c->sys_clk);
- if (ret)
- return ret;
+ pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_I2C_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ if (!pm_runtime_enabled(&pdev->dev)) {
+ ret = img_i2c_runtime_resume(&pdev->dev);
+ if (ret)
+ return ret;
+ }
ret = img_i2c_init(i2c);
if (ret)
- goto disable_clk;
+ goto rpm_disable;
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0)
- goto disable_clk;
+ goto rpm_disable;
return 0;
-disable_clk:
- clk_disable_unprepare(i2c->sys_clk);
+rpm_disable:
+ if (!pm_runtime_enabled(&pdev->dev))
+ img_i2c_runtime_suspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
return ret;
}
@@ -1408,19 +1425,55 @@ static int img_i2c_remove(struct platform_device *dev)
struct img_i2c *i2c = platform_get_drvdata(dev);
i2c_del_adapter(&i2c->adap);
+ pm_runtime_disable(&dev->dev);
+ if (!pm_runtime_status_suspended(&dev->dev))
+ img_i2c_runtime_suspend(&dev->dev);
+
+ return 0;
+}
+
+static int img_i2c_runtime_suspend(struct device *dev)
+{
+ struct img_i2c *i2c = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(i2c->scb_clk);
clk_disable_unprepare(i2c->sys_clk);
return 0;
}
+static int img_i2c_runtime_resume(struct device *dev)
+{
+ struct img_i2c *i2c = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(i2c->sys_clk);
+ if (ret) {
+ dev_err(dev, "Unable to enable sys clock\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(i2c->scb_clk);
+ if (ret) {
+ dev_err(dev, "Unable to enable scb clock\n");
+ clk_disable_unprepare(i2c->sys_clk);
+ return ret;
+ }
+
+ return 0;
+}
+
#ifdef CONFIG_PM_SLEEP
static int img_i2c_suspend(struct device *dev)
{
struct img_i2c *i2c = dev_get_drvdata(dev);
+ int ret;
- img_i2c_switch_mode(i2c, MODE_SUSPEND);
+ ret = pm_runtime_force_suspend(dev);
+ if (ret)
+ return ret;
- clk_disable_unprepare(i2c->sys_clk);
+ img_i2c_switch_mode(i2c, MODE_SUSPEND);
return 0;
}
@@ -1430,7 +1483,7 @@ static int img_i2c_resume(struct device *dev)
struct img_i2c *i2c = dev_get_drvdata(dev);
int ret;
- ret = clk_prepare_enable(i2c->sys_clk);
+ ret = pm_runtime_force_resume(dev);
if (ret)
return ret;
@@ -1440,7 +1493,12 @@ static int img_i2c_resume(struct device *dev)
}
#endif /* CONFIG_PM_SLEEP */
-static SIMPLE_DEV_PM_OPS(img_i2c_pm, img_i2c_suspend, img_i2c_resume);
+static const struct dev_pm_ops img_i2c_pm = {
+ SET_RUNTIME_PM_OPS(img_i2c_runtime_suspend,
+ img_i2c_runtime_resume,
+ NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(img_i2c_suspend, img_i2c_resume)
+};
static const struct of_device_id img_scb_i2c_match[] = {
{ .compatible = "img,scb-i2c" },
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