From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
To: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: linux-i2c <linux-i2c@vger.kernel.org>,
Wolfram Sang <wsa@the-dreams.de>,
"Rafael J. Wysocki" <rafael@kernel.org>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Rajmohan Mani <rajmohan.mani@intel.com>,
Tomasz Figa <tfiga@chromium.org>,
Bingbu Cao <bingbu.cao@intel.com>,
Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>,
Hyungwoo Yang <hyungwoo.yang@intel.com>,
linux-media <linux-media@vger.kernel.org>
Subject: Re: [PATCH v8 6/6] at24: Support probing while off
Date: Wed, 9 Sep 2020 11:35:45 +0200 [thread overview]
Message-ID: <CAMpxmJX40=iYYxL9Uvs1Pjj9c3NvZBGJ9Mh9-87T0c==FKEXRw@mail.gmail.com> (raw)
In-Reply-To: <20200903081550.6012-7-sakari.ailus@linux.intel.com>
On Thu, Sep 3, 2020 at 10:15 AM Sakari Ailus
<sakari.ailus@linux.intel.com> wrote:
>
> In certain use cases (where the chip is part of a camera module, and the
> camera module is wired together with a camera privacy LED), powering on
> the device during probe is undesirable. Add support for the at24 to
> execute probe while being powered off. For this to happen, a hint in form
> of a device property is required from the firmware.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
> drivers/misc/eeprom/at24.c | 43 +++++++++++++++++++++++---------------
> 1 file changed, 26 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 8f5de5f10bbea..2d24e33788d7d 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -595,6 +595,7 @@ static int at24_probe(struct i2c_client *client)
> bool i2c_fn_i2c, i2c_fn_block;
> unsigned int i, num_addresses;
> struct at24_data *at24;
> + bool low_power;
> struct regmap *regmap;
> bool writable;
> u8 test_byte;
> @@ -733,25 +734,30 @@ static int at24_probe(struct i2c_client *client)
>
> i2c_set_clientdata(client, at24);
>
> - err = regulator_enable(at24->vcc_reg);
> - if (err) {
> - dev_err(dev, "Failed to enable vcc regulator\n");
> - return err;
> - }
> + low_power = acpi_dev_state_low_power(&client->dev);
> + if (!low_power) {
> + err = regulator_enable(at24->vcc_reg);
> + if (err) {
> + dev_err(dev, "Failed to enable vcc regulator\n");
> + return err;
> + }
>
> - /* enable runtime pm */
> - pm_runtime_set_active(dev);
> + pm_runtime_set_active(dev);
> + }
> pm_runtime_enable(dev);
>
> /*
> - * Perform a one-byte test read to verify that the
> - * chip is functional.
> + * Perform a one-byte test read to verify that the chip is functional,
> + * unless powering on the device is to be avoided during probe (i.e.
> + * it's powered off right now).
> */
> - err = at24_read(at24, 0, &test_byte, 1);
> - if (err) {
> - pm_runtime_disable(dev);
> - regulator_disable(at24->vcc_reg);
> - return -ENODEV;
> + if (!low_power) {
> + err = at24_read(at24, 0, &test_byte, 1);
> + if (err) {
> + pm_runtime_disable(dev);
> + regulator_disable(at24->vcc_reg);
> + return -ENODEV;
> + }
> }
>
> pm_runtime_idle(dev);
> @@ -771,9 +777,11 @@ 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_disable(at24->vcc_reg);
> - pm_runtime_set_suspended(&client->dev);
> + if (!acpi_dev_state_low_power(&client->dev)) {
> + if (!pm_runtime_status_suspended(&client->dev))
> + regulator_disable(at24->vcc_reg);
> + pm_runtime_set_suspended(&client->dev);
> + }
>
> return 0;
> }
> @@ -810,6 +818,7 @@ static struct i2c_driver at24_driver = {
> .probe_new = at24_probe,
> .remove = at24_remove,
> .id_table = at24_ids,
> + .flags = I2C_DRV_FL_ALLOW_LOW_POWER_PROBE,
> };
>
> static int __init at24_init(void)
> --
> 2.20.1
>
This currently conflicts with the fix I queued for at24 for v5.9.
Which tree is going to take this series?
Bartosz
next prev parent reply other threads:[~2020-09-09 9:36 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-03 8:15 [PATCH v8 0/6] Support running driver's probe for a device powered off Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 1/6] i2c: Allow an ACPI driver to manage the device's power state during probe Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 2/6] Documentation: ACPI: Document i2c-allow-low-power-probe _DSD property Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 3/6] ACPI: Add a convenience function to tell a device is in low power state Sakari Ailus
[not found] ` <0c2d4728-6e32-ef93-8961-381fe36cfdaa@linux.intel.com>
2020-09-11 13:01 ` Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 4/6] ov5670: Support probe whilst the device is in a " Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 5/6] media: i2c: imx319: Support probe while the device is off Sakari Ailus
2020-09-03 8:15 ` [PATCH v8 6/6] at24: Support probing while off Sakari Ailus
2020-09-09 9:35 ` Bartosz Golaszewski [this message]
2020-09-09 11:11 ` Wolfram Sang
2020-09-09 11:56 ` Bartosz Golaszewski
2020-09-09 12:16 ` Sakari Ailus
2020-09-11 12:11 ` Sakari Ailus
2020-10-06 11:20 ` Tomasz Figa
2020-10-06 11:23 ` Tomasz Figa
2020-09-11 12:49 ` [PATCH v8 0/6] Support running driver's probe for a device powered off Luca Ceresoli
2020-09-11 13:01 ` Sakari Ailus
2020-09-14 7:58 ` Luca Ceresoli
[not found] ` <20200914094727.GM26842@paasikivi.fi.intel.com>
2020-09-14 16:49 ` Luca Ceresoli
2020-09-23 11:08 ` Sakari Ailus
2020-09-23 15:37 ` Luca Ceresoli
2020-09-26 12:38 ` Tomasz Figa
2020-09-27 19:39 ` Wolfram Sang
2020-09-27 19:44 ` Tomasz Figa
2020-09-28 14:17 ` Rafael J. Wysocki
2020-09-28 16:49 ` Tomasz Figa
2020-09-28 20:49 ` Sakari Ailus
2020-09-26 12:46 ` Tomasz Figa
2021-01-28 23:27 ` [PATCH v9 1/7] ACPI: scan: Obtain device's desired enumeration power state Sakari Ailus
[not found] ` <CAJZ5v0hdG1W0D5E6GbrTDiAjMyC0mSgb3Z2WEBy3hhb4iJhDNw@mail.gmail.com>
2021-01-29 16:45 ` Sakari Ailus
2021-01-29 16:57 ` Rafael J. Wysocki
2021-01-29 21:22 ` Sakari Ailus
2021-02-01 11:44 ` Rafael J. Wysocki
2021-01-28 23:27 ` [PATCH v9 2/7] i2c: Allow an ACPI driver to manage the device's power state during probe Sakari Ailus
2021-01-28 23:27 ` [PATCH v9 3/7] Documentation: ACPI: Document _PRE object usage for enum power state Sakari Ailus
2021-01-28 23:27 ` [PATCH v9 4/7] ACPI: Add a convenience function to tell a device is in low " Sakari Ailus
2021-01-28 23:27 ` [PATCH v9 5/7] ov5670: Support probe whilst the device is in a " Sakari Ailus
2021-01-28 23:27 ` [PATCH v9 6/7] media: i2c: imx319: Support probe while the device is off Sakari Ailus
2021-01-29 2:58 ` Bingbu Cao
2021-01-28 23:27 ` [PATCH v9 7/7] at24: Support probing while off Sakari Ailus
[not found] ` <CAMpxmJVTPgvxOVdTkmt4VjUnGabNBKauKF_DKtnnkV6O0QYTWA@mail.gmail.com>
[not found] ` <20210129121955.GH32460@paasikivi.fi.intel.com>
2021-02-01 8:57 ` Bartosz Golaszewski
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