Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964814Ab3HHJ0h (ORCPT ); Thu, 8 Aug 2013 05:26:37 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:13373 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934118Ab3HHJ0f (ORCPT ); Thu, 8 Aug 2013 05:26:35 -0400 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Thu, 08 Aug 2013 02:26:34 -0700 Message-ID: <52036436.4090608@nvidia.com> Date: Thu, 8 Aug 2013 17:26:14 +0800 From: Wei Ni User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: Alexander Shiyan CC: "khali@linux-fr.org" , "linux@roeck-us.net" , "swarren@wwwdotorg.org" , "linux-kernel@vger.kernel.org" , "lm-sensors@lm-sensors.org" , Matthew Longnecker , "linux-tegra@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH v2 1/3] hwmon: (lm90) Add power control References: <1375944991-29182-1-git-send-email-wni@nvidia.com> <1375944991-29182-2-git-send-email-wni@nvidia.com> <1375946022.222322391@f304.i.mail.ru> In-Reply-To: <1375946022.222322391@f304.i.mail.ru> 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 Content-Length: 2609 Lines: 96 On 08/08/2013 03:13 PM, Alexander Shiyan wrote: >> The device lm90 can be controlled by the vdd rail. >> Adding the power control support to power on/off the vdd rail. >> And make sure that power is enabled before accessing the device. >> >> Signed-off-by: Wei Ni >> --- >> drivers/hwmon/lm90.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 49 insertions(+) >> >> diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c > [...] >> +static void lm90_power_control(struct i2c_client *client, bool is_enable) >> +{ >> + struct lm90_data *data = i2c_get_clientdata(client); >> + int ret; >> + >> + if (!data->lm90_reg) >> + return; >> + >> + mutex_lock(&data->update_lock); >> + >> + if (is_enable) >> + ret = regulator_enable(data->lm90_reg); >> + else >> + ret = regulator_disable(data->lm90_reg); >> + >> + if (ret < 0) >> + dev_err(&client->dev, >> + "Error in %s rail vdd, error %d\n", >> + (is_enable) ? "enabling" : "disabling", ret); >> + else >> + dev_info(&client->dev, "success in %s rail vdd\n", >> + (is_enable) ? "enabling" : "disabling"); > > dev_dbg() ? As Guenter said, I will remove these messages, and remove this function, the code will be more clean. > >> + >> + mutex_unlock(&data->update_lock); >> +} >> + >> static int lm90_probe(struct i2c_client *client, >> const struct i2c_device_id *id) >> { >> @@ -1406,6 +1434,20 @@ static int lm90_probe(struct i2c_client *client, >> i2c_set_clientdata(client, data); >> mutex_init(&data->update_lock); >> >> + data->lm90_reg = regulator_get(&client->dev, "vdd"); >> + if (IS_ERR_OR_NULL(data->lm90_reg)) { > > What about deferred probe? > if (PTR_ERR(data->lm90_reg) == -EPROBE_DEFER) > return -EPROBE_DEFER; Oh, yes, I should add it. > >> + if (PTR_ERR(data->lm90_reg) == -ENODEV) >> + dev_info(&client->dev, >> + "No regulator found for vdd. Assuming vdd is always powered."); > > On my opinion it is unnecessary message. > >> + else >> + dev_warn(&client->dev, >> + "Error [%ld] in getting the regulator handle for vdd.\n", >> + PTR_ERR(data->lm90_reg)); > > Ditto. I will remove these log messages. > >> + data->lm90_reg = NULL; > > You can just use !IS_ERR(data->lm90_reg) macro in the future, > rather than set this to NULL. Yes, it's better, I will do it. > > [...] > > --- > -- 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/