śr., 23 paź 2019 o 11:22 Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx> napisał(a):
>
> On Wed, 2019-10-23 at 10:44 +0200, Bartosz Golaszewski wrote:
> > śr., 23 paź 2019 o 10:22 Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx> napisał(a):
> > >
> > > Although in the most platforms, the power of eeprom and i2c
> > > are alway on, some platforms disable the eeprom and i2c power
> > > in order to meet low power request.
> > > This patch add the pm_runtime ops to control power to support
> > > all platforms.
> > >
> > > Changes since v5:
> > > - remove has_supplies
> > >
> > > Changes since v4:
> > > - add system sleep PM ops
> > > - move regulator_bulk_disable before suspend()
> > > - fixes error handling
> > >
> > > Changes since v3:
> > > - remove redundant calling function
> > > - change SIMPLE_DEV_PM_OPS to SET_RUNTIME_PM_OPS
> > > - change supply name
> > >
> > > Changes since v2:
> > > - rebase onto v5.4-rc1
> > > - pm_runtime_disable and regulator_bulk_disable at
> > > err return in probe function
> > >
> > > Changes since v1:
> > > - remove redundant code
> > > - fixup coding style
> > >
> > > Signed-off-by: Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx>
> > > ---
> > > drivers/misc/eeprom/at24.c | 50 ++++++++++++++++++++++++++++++++++++++
> > > 1 file changed, 50 insertions(+)
> > >
> > > diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> > > index 2cccd82a3106..1332bba93d32 100644
> > > --- a/drivers/misc/eeprom/at24.c
> > > +++ b/drivers/misc/eeprom/at24.c
> > > @@ -22,6 +22,7 @@
> > > #include <linux/nvmem-provider.h>
> > > #include <linux/regmap.h>
> > > #include <linux/pm_runtime.h>
> > > +#include <linux/regulator/consumer.h>
> > > #include <linux/gpio/consumer.h>
> > >
> > > /* Address pointer is 16 bit. */
> > > @@ -67,6 +68,12 @@
> > > * which won't work on pure SMBus systems.
> > > */
> > >
> > > +static const char * const at24_supply_names[] = {
> > > + "vcc", "i2c",
> > > +};
> > > +
> > > +#define AT24_NUM_SUPPLIES ARRAY_SIZE(at24_supply_names)
> > > +
> > > struct at24_client {
> > > struct i2c_client *client;
> > > struct regmap *regmap;
> > > @@ -91,6 +98,7 @@ struct at24_data {
> > >
> > > struct gpio_desc *wp_gpio;
> > >
> > > + struct regulator_bulk_data supplies[AT24_NUM_SUPPLIES];
> > > /*
> > > * Some chips tie up multiple I2C addresses; dummy devices reserve
> > > * them for us, and we'll use them with SMBus calls.
> > > @@ -662,6 +670,11 @@ static int at24_probe(struct i2c_client *client)
> > > at24->client[0].client = client;
> > > at24->client[0].regmap = regmap;
> > >
> > > + regulator_bulk_set_supply_names(at24->supplies,
> > > + at24_supply_names, AT24_NUM_SUPPLIES);
> > > + devm_regulator_bulk_get(&at24->client[0].client->dev,
> > > + AT24_NUM_SUPPLIES, at24->supplies);
> >
> > You still need to check the return value here - this call can still
> > fail for many reasons.
>
> I think we can easily check if return value < 0, rigth?
>
Check the documentation for this function. I'd guess it's a negative errno, yes.
Bart
>
> > > +
> > > at24->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_HIGH);
> > > if (IS_ERR(at24->wp_gpio))
> > > return PTR_ERR(at24->wp_gpio);
> > > @@ -701,6 +714,12 @@ static int at24_probe(struct i2c_client *client)
> > >
> > > i2c_set_clientdata(client, at24);
> > >
> > > + err = regulator_bulk_enable(AT24_NUM_SUPPLIES, at24->supplies);
> > > + if (err) {
> > > + dev_err(dev, "Failed to enable power regulators\n");
> > > + return err;
> > > + }
> > > +
> > > /* enable runtime pm */
> > > pm_runtime_set_active(dev);
> > > pm_runtime_enable(dev);
> > > @@ -713,6 +732,8 @@ static int at24_probe(struct i2c_client *client)
> > > pm_runtime_idle(dev);
> > > if (err) {
> > > pm_runtime_disable(dev);
> > > + regulator_bulk_disable(AT24_NUM_SUPPLIES,
> > > + at24->supplies);
> > > return -ENODEV;
> > > }
> > >
> > > @@ -725,15 +746,44 @@ static int at24_probe(struct i2c_client *client)
> > >
> > > static int at24_remove(struct i2c_client *client)
> > > {
> > > + struct at24_data *at24 = i2c_get_clientdata(client);
> > > +
> > > pm_runtime_disable(&client->dev);
> > > + if (pm_runtime_status_suspended(&client->dev))
> > > + regulator_bulk_disable(AT24_NUM_SUPPLIES, at24->supplies);
> >
> > So you will now disable the regulators if they're already disabled in
> > at24_suspend() but not disable them if they're not. This is clearly
> > inverted.
> >
> > Bart
>
> oops... I miss inverted, sorry :(
>
> Bibby
>
> >
> > > pm_runtime_set_suspended(&client->dev);
> > >
> > > return 0;
> > > }
> > >
> > > +static int __maybe_unused at24_suspend(struct device *dev)
> > > +{
> > > + struct i2c_client *client = to_i2c_client(dev);
> > > + struct at24_data *at24 = i2c_get_clientdata(client);
> > > +
> > > + return regulator_bulk_disable(AT24_NUM_SUPPLIES,
> > > + at24->supplies);
> > > +}
> > > +
> > > +static int __maybe_unused at24_resume(struct device *dev)
> > > +{
> > > + struct i2c_client *client = to_i2c_client(dev);
> > > + struct at24_data *at24 = i2c_get_clientdata(client);
> > > +
> > > + return regulator_bulk_enable(AT24_NUM_SUPPLIES,
> > > + at24->supplies);
> > > +}
> > > +
> > > +static const struct dev_pm_ops at24_pm_ops = {
> > > + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> > > + pm_runtime_force_resume)
> > > + SET_RUNTIME_PM_OPS(at24_suspend, at24_resume, NULL)
> > > +};
> > > +
> > > static struct i2c_driver at24_driver = {
> > > .driver = {
> > > .name = "at24",
> > > + .pm = &at24_pm_ops,
> > > .of_match_table = at24_of_match,
> > > .acpi_match_table = ACPI_PTR(at24_acpi_ids),
> > > },
> > > --
> > > 2.18.0
> > >
>
>
