From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: Re: [PATCH v3 6/6] mfd: max77620: Provide system power-off functionality Date: Thu, 25 Apr 2019 13:22:41 +0200 Message-ID: <20190425112241.GA10218@ulmo> References: <20190424224900.8018-1-digetx@gmail.com> <20190424224900.8018-7-digetx@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="ZPt4rx8FFjLCG7dd" Return-path: Content-Disposition: inline In-Reply-To: <20190424224900.8018-7-digetx@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Dmitry Osipenko Cc: Lee Jones , Rob Herring , Mark Rutland , Liam Girdwood , Mark Brown , Laxman Dewangan , Mallikarjun Kasoju , Jonathan Hunter , devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org --ZPt4rx8FFjLCG7dd Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Apr 25, 2019 at 01:49:00AM +0300, Dmitry Osipenko wrote: > Provide system power-off functionality that allows to turn off machine > gracefully. >=20 > Signed-off-by: Dmitry Osipenko > --- > drivers/mfd/max77620.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) >=20 > diff --git a/drivers/mfd/max77620.c b/drivers/mfd/max77620.c > index 9b0009c29610..e56223bde568 100644 > --- a/drivers/mfd/max77620.c > +++ b/drivers/mfd/max77620.c > @@ -37,6 +37,8 @@ > #include > #include > =20 > +static struct max77620_chip *max77620_scratch; > + > static const struct resource gpio_resources[] =3D { > DEFINE_RES_IRQ(MAX77620_IRQ_TOP_GPIO), > }; > @@ -481,6 +483,15 @@ static int max77620_read_es_version(struct max77620_= chip *chip) > return ret; > } > =20 > +static void max77620_pm_power_off(void) > +{ > + struct max77620_chip *chip =3D max77620_scratch; > + > + regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG1, > + MAX77620_ONOFFCNFG1_SFT_RST, > + MAX77620_ONOFFCNFG1_SFT_RST); > +} I think this is only partially correct. See here for a driver that I had proposed a while back: https://github.com/thierryreding/linux/commit/d0eaa77b402f62bd236d76e3edeb= 3ccf296cbe81 Note that that driver is part of a larger series to move away from all the pm_power_off hackery. There was a fair bit of discussion back when I proposed the original power off driver for max77620: https://lkml.org/lkml/2017/1/12/470 I think I may have a more up-to-date local branch of the system-power branch from my github repository if you're interested in looking at some of that code. There wasn't a whole lot of feedback on the patches, but the feedback I did get was generally positive. However, since it didn't gain any traction I eventually abandoned that effort. It might be worth picking it up again, since, as far as I can tell, the situation around power off and restart hasn't changed in the meantime. Thierry > + > static int max77620_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > @@ -488,6 +499,7 @@ static int max77620_probe(struct i2c_client *client, > struct max77620_chip *chip; > const struct mfd_cell *mfd_cells; > int n_mfd_cells; > + bool pm_off; > int ret; > =20 > chip =3D devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); > @@ -554,6 +566,13 @@ static int max77620_probe(struct i2c_client *client, > return ret; > } > =20 > + pm_off =3D of_property_read_bool(client->dev.of_node, > + "maxim,system-power-controller"); > + if (pm_off && !pm_power_off) { > + max77620_scratch =3D chip; > + pm_power_off =3D max77620_pm_power_off; > + } > + > return 0; > } > =20 > --=20 > 2.21.0 >=20 --ZPt4rx8FFjLCG7dd Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAlzBmH4ACgkQ3SOs138+ s6FW4Q//WwGUmKeVX9G+JztP+onk6z3UHZYwUuKhumFVhdbzSPwmjvhzyU8cG44z +n+aremYlkCHa+wQbZHe55kBqke9GFOUOWswgfYZIwRYzyMxklrNYHLaCjKnDiRU 0tstURpNyaYhGSKAWez5jAxJgZOBNJsn6VRiu9nc6dj3DlqtXG5azGdDXArwyZhn 7C3suAH9ktZ2wfFM3fZ8sI30of24Bqx4qgf1mRrxhS1dJtipQUwMyVAsFehf54c8 YsyDMbL4b4H4UtcsM+gF6lfyRFfakcMz9D6bzj2jdMfxYYRf/tz94FnQb4x8oMXX O/FohlW3UyOCxjjXIrIibkC/z6C/0YI1zjwwesNsIg3qz1KaoUjbFvfyfNfk2Xzy zmtEhwiHxAqxxVlemzYbiqFMtbWA+7FSKMycC3peszvQ4GbDgg3Masd42D4YFBFE dIDG7qe6rVYCL7+lCYJVIgdO0DuaOkzqEmzZkSeO3iRFhO/24ZzUp6Y9fk3jcCn9 QxJb6L5pkWHRhJvqQEDM4tX6bj8XfYhhd0rY3AfOC4CRQiAz/5n/SRcCy+wYAHGE HfO89UuNhAz75Md+jQCXUzevDvJcLBn7z/I4QZ4Is4qKcVlSwrRfbSxWmsTwVjz7 IfWA+z3BgnkARPUJZGZ41XhYKa/jVLMudMuc2vI7bbGUsolJuGo= =2OHv -----END PGP SIGNATURE----- --ZPt4rx8FFjLCG7dd--