* [PATCH v13 1/2] dt-binding: i2c: add bus-supply property
2020-04-21 5:18 [PATCH v13 0/2] add power control in i2c Bibby Hsieh
@ 2020-04-21 5:18 ` Bibby Hsieh
2020-04-22 20:14 ` Rob Herring
2020-04-21 5:18 ` [PATCH v13 2/2] i2c: core: support bus regulator controlling in adapter Bibby Hsieh
1 sibling, 1 reply; 5+ messages in thread
From: Bibby Hsieh @ 2020-04-21 5:18 UTC (permalink / raw)
To: Wolfram Sang, Bartosz Golaszewski, linux-i2c
Cc: tfiga, drinkcat, srv_heupstream, robh+dt, mark.rutland,
devicetree, Rafael J . Wysocki, Bibby Hsieh
In some platforms, they disable the power-supply of SCL/SDA due
to power consumption reduction. This patch add bus-supply property.
Signed-off-by: Bibby Hsieh <bibby.hsieh@mediatek.com>
---
Documentation/devicetree/bindings/i2c/i2c.txt | 3 +++
1 file changed, 3 insertions(+)
diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt
index 9a53df4243c6..e6b5aafc5dc9 100644
--- a/Documentation/devicetree/bindings/i2c/i2c.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c.txt
@@ -98,6 +98,9 @@ wants to support one of the below features, it should adapt the bindings below.
Names of map programmable addresses.
It can contain any map needing another address than default one.
+- bus-supply
+ phandle to the regulator that provides power to SCL/SDA.
+
Binding may contain optional "interrupts" property, describing interrupts
used by the device. I2C core will assign "irq" interrupt (or the very first
interrupt if not using interrupt names) as primary interrupt for the slave.
--
2.18.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v13 2/2] i2c: core: support bus regulator controlling in adapter
2020-04-21 5:18 [PATCH v13 0/2] add power control in i2c Bibby Hsieh
2020-04-21 5:18 ` [PATCH v13 1/2] dt-binding: i2c: add bus-supply property Bibby Hsieh
@ 2020-04-21 5:18 ` Bibby Hsieh
2020-04-21 15:24 ` Tomasz Figa
1 sibling, 1 reply; 5+ messages in thread
From: Bibby Hsieh @ 2020-04-21 5:18 UTC (permalink / raw)
To: Wolfram Sang, Bartosz Golaszewski, linux-i2c
Cc: tfiga, drinkcat, srv_heupstream, robh+dt, mark.rutland,
devicetree, Rafael J . Wysocki, Bibby Hsieh
Although in the most platforms, the bus power of i2c
are alway on, some platforms disable the i2c bus power
in order to meet low power request.
We get and enable bulk regulator in i2c adapter device.
Signed-off-by: Bibby Hsieh <bibby.hsieh@mediatek.com>
---
drivers/i2c/i2c-core-base.c | 82 +++++++++++++++++++++++++++++++++++++
include/linux/i2c.h | 2 +
2 files changed, 84 insertions(+)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 5cc0b0ec5570..b3d15d6d449d 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -313,6 +313,7 @@ static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client)
static int i2c_device_probe(struct device *dev)
{
struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
struct i2c_driver *driver;
int status;
@@ -378,6 +379,12 @@ static int i2c_device_probe(struct device *dev)
dev_dbg(dev, "probe\n");
+ status = regulator_enable(adap->bus_regulator);
+ if (status < 0) {
+ dev_err(&adap->dev, "Failed to enable power regulator\n");
+ goto err_clear_wakeup_irq;
+ }
+
status = of_clk_set_defaults(dev->of_node, false);
if (status < 0)
goto err_clear_wakeup_irq;
@@ -414,6 +421,7 @@ static int i2c_device_probe(struct device *dev)
static int i2c_device_remove(struct device *dev)
{
struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
struct i2c_driver *driver;
int status = 0;
@@ -427,6 +435,8 @@ static int i2c_device_remove(struct device *dev)
}
dev_pm_domain_detach(&client->dev, true);
+ if (!pm_runtime_status_suspended(&client->dev))
+ regulator_disable(adap->bus_regulator);
dev_pm_clear_wake_irq(&client->dev);
device_init_wakeup(&client->dev, false);
@@ -438,6 +448,72 @@ static int i2c_device_remove(struct device *dev)
return status;
}
+#ifdef CONFIG_PM_SLEEP
+static int i2c_resume_early(struct device *dev)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
+ int err;
+
+ if (pm_runtime_status_suspended(&client->dev)) {
+ err = regulator_enable(adap->bus_regulator);
+ if (err)
+ return err;
+ }
+
+ return pm_generic_resume_early(&client->dev);
+}
+
+static int i2c_suspend_late(struct device *dev)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
+ int err;
+
+ err = pm_generic_suspend_late(&client->dev);
+ if (err)
+ return err;
+
+ if (!pm_runtime_status_suspended(&client->dev))
+ return regulator_disable(adap->bus_regulator);
+
+ return err;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int i2c_runtime_resume(struct device *dev)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
+ int err;
+
+ err = regulator_enable(adap->bus_regulator);
+ if (err)
+ return err;
+
+ return pm_generic_runtime_resume(&client->dev);
+}
+
+static int i2c_runtime_suspend(struct device *dev)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_adapter *adap = client->adapter;
+ int err;
+
+ err = pm_generic_runtime_suspend(&client->dev);
+ if (err)
+ return err;
+
+ return regulator_disable(adap->bus_regulator);
+}
+#endif
+
+static const struct dev_pm_ops i2c_device_pm = {
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(i2c_suspend_late, i2c_resume_early)
+ SET_RUNTIME_PM_OPS(i2c_runtime_suspend, i2c_runtime_resume, NULL)
+};
+
static void i2c_device_shutdown(struct device *dev)
{
struct i2c_client *client = i2c_verify_client(dev);
@@ -495,6 +571,7 @@ struct bus_type i2c_bus_type = {
.probe = i2c_device_probe,
.remove = i2c_device_remove,
.shutdown = i2c_device_shutdown,
+ .pm = &i2c_device_pm,
};
EXPORT_SYMBOL_GPL(i2c_bus_type);
@@ -1333,6 +1410,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
if (res)
goto out_reg;
+ adap->bus_regulator = devm_regulator_get(&adap->dev, "bus");
+ if (IS_ERR(adap->bus_regulator)) {
+ res = PTR_ERR(adap->bus_regulator);
+ goto out_reg;
+ }
dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name);
pm_runtime_no_callbacks(&adap->dev);
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 456fc17ecb1c..bc83af0d38d1 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -15,6 +15,7 @@
#include <linux/device.h> /* for struct device */
#include <linux/sched.h> /* for completion */
#include <linux/mutex.h>
+#include <linux/regulator/consumer.h>
#include <linux/rtmutex.h>
#include <linux/irqdomain.h> /* for Host Notify IRQ */
#include <linux/of.h> /* for struct device_node */
@@ -721,6 +722,7 @@ struct i2c_adapter {
const struct i2c_adapter_quirks *quirks;
struct irq_domain *host_notify_domain;
+ struct regulator *bus_regulator;
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
--
2.18.0
^ permalink raw reply related [flat|nested] 5+ messages in thread