Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965983AbaLKXc4 (ORCPT ); Thu, 11 Dec 2014 18:32:56 -0500 Received: from mail-qa0-f47.google.com ([209.85.216.47]:60948 "EHLO mail-qa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964971AbaLKXcy (ORCPT ); Thu, 11 Dec 2014 18:32:54 -0500 Message-ID: <548A29A4.7060908@hurleysoftware.com> Date: Thu, 11 Dec 2014 18:32:52 -0500 From: Peter Hurley User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: NeilBrown , Grant Likely , Greg Kroah-Hartman , Mark Rutland , Jiri Slaby CC: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] TTY: add slave driver to power-on device via a regulator. References: <20141211214801.4127.93914.stgit@notabene.brown> <20141211215944.4127.4186.stgit@notabene.brown> In-Reply-To: <20141211215944.4127.4186.stgit@notabene.brown> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/11/2014 04:59 PM, NeilBrown wrote: > The regulator is identified in devicetree as 'vdd-supply' > > Signed-off-by: NeilBrown tty_* is only for tty core functions/data. Regards, Peter Hurley > --- > .../devicetree/bindings/serial/slave-reg.txt | 18 ++++ > drivers/tty/Kconfig | 2 > drivers/tty/Makefile | 1 > drivers/tty/slaves/Kconfig | 12 ++ > drivers/tty/slaves/Makefile | 2 > drivers/tty/slaves/tty-reg.c | 102 ++++++++++++++++++++ > 6 files changed, 137 insertions(+) > create mode 100644 Documentation/devicetree/bindings/serial/slave-reg.txt > create mode 100644 drivers/tty/slaves/Kconfig > create mode 100644 drivers/tty/slaves/Makefile > create mode 100644 drivers/tty/slaves/tty-reg.c > > diff --git a/Documentation/devicetree/bindings/serial/slave-reg.txt b/Documentation/devicetree/bindings/serial/slave-reg.txt > new file mode 100644 > index 000000000000..7896bce8dfe4 > --- /dev/null > +++ b/Documentation/devicetree/bindings/serial/slave-reg.txt > @@ -0,0 +1,18 @@ > +Regulator powered UART-attached device > + > +Required properties: > +- compatible: "tty,regulator" > +- vdd-supply: regulator to power the device > + > + > +This is listed as a child node of a UART. When the > +UART is opened, the device is powered. > + > +Example: > + > +&uart1 { > + bluetooth { > + compatible = "tty,regulator"; > + vdd-supply = <&vaux4>; > + }; > +}; > diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig > index b24aa010f68c..ea3383c71701 100644 > --- a/drivers/tty/Kconfig > +++ b/drivers/tty/Kconfig > @@ -419,4 +419,6 @@ config DA_CONSOLE > help > This enables a console on a Dash channel. > > +source drivers/tty/slaves/Kconfig > + > endif # TTY > diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile > index 58ad1c05b7f8..45957d671e33 100644 > --- a/drivers/tty/Makefile > +++ b/drivers/tty/Makefile > @@ -13,6 +13,7 @@ obj-$(CONFIG_R3964) += n_r3964.o > obj-y += vt/ > obj-$(CONFIG_HVC_DRIVER) += hvc/ > obj-y += serial/ > +obj-$(CONFIG_TTY_SLAVE) += slaves/ > > # tty drivers > obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o > diff --git a/drivers/tty/slaves/Kconfig b/drivers/tty/slaves/Kconfig > new file mode 100644 > index 000000000000..2dd1acf80f8c > --- /dev/null > +++ b/drivers/tty/slaves/Kconfig > @@ -0,0 +1,12 @@ > +menuconfig TTY_SLAVE > + bool "TTY slave devices" > + help > + Devices which attach via a uart, but need extra > + driver support for power management etc. > + > +if TTY_SLAVE > + > +config TTY_SLAVE_REGULATOR > + tristate "TTY slave device powered by regulator" > + > +endif > diff --git a/drivers/tty/slaves/Makefile b/drivers/tty/slaves/Makefile > new file mode 100644 > index 000000000000..e636bf49f1cc > --- /dev/null > +++ b/drivers/tty/slaves/Makefile > @@ -0,0 +1,2 @@ > + > +obj-$(CONFIG_TTY_SLAVE_REGULATOR) += tty-reg.o > diff --git a/drivers/tty/slaves/tty-reg.c b/drivers/tty/slaves/tty-reg.c > new file mode 100644 > index 000000000000..613f8b10967c > --- /dev/null > +++ b/drivers/tty/slaves/tty-reg.c > @@ -0,0 +1,102 @@ > +/* > + * tty-reg: > + * Support for any device which needs a regulator turned on > + * when a tty is opened. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct tty_reg_data { > + struct regulator *reg; > + bool reg_enabled; > +}; > + > +static int tty_reg_runtime_resume(struct device *slave) > +{ > + struct tty_reg_data *data = dev_get_drvdata(slave); > + if (!data->reg_enabled && > + regulator_enable(data->reg) == 0) { > + dev_dbg(slave, "power on\n"); > + data->reg_enabled = true; > + } > + return 0; > +} > + > +static int tty_reg_runtime_suspend(struct device *slave) > +{ > + struct tty_reg_data *data = dev_get_drvdata(slave); > + > + if (data->reg_enabled && > + regulator_disable(data->reg) == 0) { > + dev_dbg(slave, "power off\n"); > + data->reg_enabled = false; > + } > + return 0; > +} > + > +static int tty_reg_probe(struct platform_device *pdev) > +{ > + struct tty_reg_data *data; > + struct regulator *reg; > + int err; > + > + err = -ENODEV; > + if (pdev->dev.parent == NULL) > + goto out; > + reg = devm_regulator_get(&pdev->dev, "vdd"); > + err = PTR_ERR(reg); > + if (IS_ERR(reg)) > + goto out; > + > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); > + err = -ENOMEM; > + if (!data) > + goto out; > + data->reg = reg; > + data->reg_enabled = false; > + pm_runtime_enable(&pdev->dev); > + platform_set_drvdata(pdev, data); > + err = 0; > +out: > + return err; > +} > + > +static struct of_device_id tty_reg_dt_ids[] = { > + { .compatible = "tty,regulator", }, > + {} > +}; > + > +static const struct dev_pm_ops tty_reg_pm_ops = { > + SET_RUNTIME_PM_OPS(tty_reg_runtime_suspend, > + tty_reg_runtime_resume, NULL) > +}; > + > +static struct platform_driver tty_reg_driver = { > + .driver.name = "tty-regulator", > + .driver.owner = THIS_MODULE, > + .driver.of_match_table = tty_reg_dt_ids, > + .driver.pm = &tty_reg_pm_ops, > + .probe = tty_reg_probe, > +}; > + > +static int __init tty_reg_init(void) > +{ > + return platform_driver_register(&tty_reg_driver); > +} > +module_init(tty_reg_init); > + > +static void __exit tty_reg_exit(void) > +{ > + platform_driver_unregister(&tty_reg_driver); > +} > +module_exit(tty_reg_exit); > + > +MODULE_AUTHOR("NeilBrown "); > +MODULE_DESCRIPTION("Serial port device which requires a regulator when open."); > +MODULE_LICENSE("GPL v2"); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/