From patchwork Sat Oct 22 20:46:21 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "H. Nikolaus Schaller" X-Patchwork-Id: 9390891 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2C6B7600CB for ; Sat, 22 Oct 2016 20:46:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1089528ED2 for ; Sat, 22 Oct 2016 20:46:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0495428ED7; Sat, 22 Oct 2016 20:46:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EDEE328ED2 for ; Sat, 22 Oct 2016 20:46:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756073AbcJVUql (ORCPT ); Sat, 22 Oct 2016 16:46:41 -0400 Received: from mo4-p00-ob.smtp.rzone.de ([81.169.146.160]:38738 "EHLO mo4-p00-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751816AbcJVUqj (ORCPT ); Sat, 22 Oct 2016 16:46:39 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1477169194; l=9163; s=domk; d=goldelico.com; h=To:References:Content-Transfer-Encoding:Cc:Date:In-Reply-To:From: Subject:Mime-Version:Content-Type; bh=P21sXhJeWV/z9Nm+0KCkHzItR2mujUAXCfpa5GkC5zg=; b=tCWSWbrwrhH21VKxNvZnFGJsWuyHwW2vwkz19YV+7+MkbbmWgzI9+Wt68M/DiYZ7Yv3 6XldUTEyileFeJMI/dYSwVsRd9X8MOHhea+dGr8beumEgof0CIABVFosZeBnkmqHjOIRz PqdLMKSh8MxzC+ZhEUfbDutjRRuxtE8RP2Q= X-RZG-AUTH: :JGIXVUS7cutRB/49FwqZ7WcZa0CjPwrtwsa7s0mYZj78qgN2BSA96A== X-RZG-CLASS-ID: mo00 Received: from [192.168.2.107] (p57AE0451.dip0.t-ipconnect.de [87.174.4.81]) by post.strato.de (RZmta 39.6 DYNA|AUTH) with ESMTPA id g06b12s9MKkMAEk; Sat, 22 Oct 2016 22:46:22 +0200 (CEST) Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: [PATCH v4 4/8] drivers:input:tsc2007: add iio interface to read external ADC input and temperature From: "H. Nikolaus Schaller" In-Reply-To: <07bb4d52-a439-f9a9-8593-ddde8e93e6ee@kernel.org> Date: Sat, 22 Oct 2016 22:46:21 +0200 Cc: Dmitry Torokhov , Rob Herring , Mark Rutland , =?windows-1252?Q?Beno=EEt_Cousson?= , Tony Lindgren , Russell King , Arnd Bergmann , Michael Welling , =?windows-1252?Q?Mika_Penttil=E4?= , Javier Martinez Canillas , Igor Grinberg , Sebastian Reichel , "Andrew F. Davis" , Mark Brown , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, letux-kernel@openphoenux.org, linux-iio@vger.kernel.org, kernel@pyra-handheld.com Message-Id: <7A0E332C-4930-4F1A-8320-F87F864B53AE@goldelico.com> References: <4d3c600bf0a6b75a74212a103bf31525505290a0.1476712675.git.hns@goldelico.com> <07bb4d52-a439-f9a9-8593-ddde8e93e6ee@kernel.org> To: Jonathan Cameron X-Mailer: Apple Mail (2.3124) Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi Jonathan, > Am 22.10.2016 um 20:33 schrieb Jonathan Cameron : > > On 17/10/16 14:57, H. Nikolaus Schaller wrote: >> The tsc2007 chip not only has a resistive touch screen controller but >> also an external AUX adc imput which can be used for an ambient >> light sensor, battery voltage monitoring or any general purpose. >> >> Additionally it can measure the chip temperature. >> >> This extension provides an iio interface for these adc channels. >> >> Since it is not wasting much resources and is very straightforward, >> we simply provide all other adc channels as optional iio interfaces >> as weel. This can be used for debugging or special applications. > well >> >> Signed-off-by: H. Nikolaus Schaller > This could be cleaner done perhaps by factoring out the IIO stuff into a separate > file and using a header with stubs to deal with the no available case. > > There will only be a handful of stubs and it'll give you a lot cleaner code > in here. > > If def fun in .c files is always harder to deal with than in a header > where stubs are really obvious. Yes, it became a lot of #ifdefs spread over the source file. The easiest thing would be to require IIO to be enabled :) With your proposal to consider refactoring, I think the crucial part is the conditional allocation either through devm_iio_device_alloc() or devm_kzalloc(). This can be refactored into some conditional tsc2007_alloc(). I have tried some draft (not tested and not tidied up) to check if the direction is good. This reduces the number of #ifdef CONFIG_IIO from 7 to 2 without introducing new files or includes. There are also 2 other #ifdef CONFIG_OF so it doesn't seem to be very complex now in comparison. And the patch itself has only a handful of hunks (8). Moving tsc2007_alloc into a separate file tsc2007_iio.c would only move around one #ifdef CONFIG_OF from tsc2007.c but IMHO makes it more difficult to understand because it is not really iio specific and one has to switch between two source files. And I would have to touch the Makefile as well. What do you think? If generally ok, I can include that in [PATCH v5]. BR and thanks, Nikolaus --- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c index 5e3c4bf..691e79f 100644 --- a/drivers/input/touchscreen/tsc2007.c +++ b/drivers/input/touchscreen/tsc2007.c @@ -30,6 +30,7 @@ #include #include #include +#include #define TSC2007_MEASURE_TEMP0 (0x0 << 4) #define TSC2007_MEASURE_AUX (0x2 << 4) @@ -69,9 +70,13 @@ struct ts_event { struct tsc2007 { struct input_dev *input; +#ifdef CONFIG_IIO + struct iio_dev *indio; +#endif char phys[32]; struct i2c_client *client; + struct mutex mlock; u16 model; u16 x_plate_ohms; @@ -192,7 +197,10 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle) while (!ts->stopped && tsc2007_is_pen_down(ts)) { /* pen is down, continue with the measurement */ + + mutex_lock(&ts->mlock); tsc2007_read_values(ts, &tc); + mutex_unlock(&ts->mlock); rt = tsc2007_calculate_resistance(ts, &tc); @@ -319,6 +327,162 @@ static void tsc2007_close(struct input_dev *input_dev) tsc2007_stop(ts); } +#ifdef CONFIG_IIO + +#define TSC2007_CHAN_IIO(_chan, _name, _type, _chan_info) \ +{ \ + .datasheet_name = _name, \ + .type = _type, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(_chan_info), \ + .indexed = 1, \ + .channel = _chan, \ +} + +static const struct iio_chan_spec tsc2007_iio_channel[] = { + TSC2007_CHAN_IIO(0, "x", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(1, "y", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(2, "z1", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(3, "z2", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(4, "adc", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(5, "rt", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), /* Ohms? */ + TSC2007_CHAN_IIO(6, "pen", IIO_PRESSURE, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(7, "temp0", IIO_TEMP, IIO_CHAN_INFO_RAW), + TSC2007_CHAN_IIO(8, "temp1", IIO_TEMP, IIO_CHAN_INFO_RAW), +}; + +static int tsc2007_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, long mask) +{ + struct tsc2007 *tsc = iio_priv(indio_dev); + int adc_chan = chan->channel; + int ret = 0; + + if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel)) + return -EINVAL; + + if (mask != IIO_CHAN_INFO_RAW) + return -EINVAL; + + mutex_lock(&tsc->mlock); + + switch (chan->channel) { + case 0: + *val = tsc2007_xfer(tsc, READ_X); + break; + case 1: + *val = tsc2007_xfer(tsc, READ_Y); + break; + case 2: + *val = tsc2007_xfer(tsc, READ_Z1); + break; + case 3: + *val = tsc2007_xfer(tsc, READ_Z2); + break; + case 4: + *val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX)); + break; + case 5: { + struct ts_event tc; + + tc.x = tsc2007_xfer(tsc, READ_X); + tc.z1 = tsc2007_xfer(tsc, READ_Z1); + tc.z2 = tsc2007_xfer(tsc, READ_Z2); + *val = tsc2007_calculate_resistance(tsc, &tc); + break; + } + case 6: + *val = tsc2007_is_pen_down(tsc); + break; + case 7: + *val = tsc2007_xfer(tsc, + (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0)); + break; + case 8: + *val = tsc2007_xfer(tsc, + (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1)); + break; + } + + /* Prepare for next touch reading - power down ADC, enable PENIRQ */ + tsc2007_xfer(tsc, PWRDOWN); + + mutex_unlock(&tsc->mlock); + + ret = IIO_VAL_INT; + + return ret; +} + +static const struct iio_info tsc2007_iio_info = { + .read_raw = tsc2007_read_raw, + .driver_module = THIS_MODULE, +}; + +static int tsc2007_alloc(struct i2c_client *client, struct tsc2007 **ts, + struct input_dev **input_dev) +{ + int err; + struct iio_dev *indio_dev; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*ts)); + if (!indio_dev) { + dev_err(&client->dev, "iio_device_alloc failed\n"); + return -ENOMEM; + } + + *ts = iio_priv(indio_dev); + + *input_dev = devm_input_allocate_device(&client->dev); + if (!*input_dev) + return -ENOMEM; + + i2c_set_clientdata(client, *ts); + (*ts)->indio = indio_dev; + + indio_dev->name = "tsc2007"; + indio_dev->dev.parent = &client->dev; + indio_dev->info = &tsc2007_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = tsc2007_iio_channel; + indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel); + + err = iio_device_register(indio_dev); + if (err < 0) { + dev_err(&client->dev, "iio_device_register() failed: %d\n", + err); + return err; + } + + return 0; +} + +#define tsc2007_iio_device_unregister(ts) iio_device_unregister(ts->indio) + +#else /* CONFIG_IIO */ + +static int tsc2007_alloc(struct i2c_client *client, struct tsc2007 **ts, + struct input_dev **input_dev) +{ + int err; + + *ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL); + if (!*ts) + return -ENOMEM; + + *input_dev = devm_input_allocate_device(&client->dev); + if (!*input_dev) + return -ENOMEM; + + i2c_set_clientdata(client, *ts); + + return 0; +} + +#define tsc2007_iio_device_unregister(ts) /* not needed */ + +#endif /* CONFIG_IIO */ + #ifdef CONFIG_OF static int tsc2007_get_pendown_state_gpio(struct device *dev) { @@ -459,20 +623,15 @@ static int tsc2007_probe(struct i2c_client *client, I2C_FUNC_SMBUS_READ_WORD_DATA)) return -EIO; - ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL); - if (!ts) - return -ENOMEM; - - input_dev = devm_input_allocate_device(&client->dev); - if (!input_dev) - return -ENOMEM; - - i2c_set_clientdata(client, ts); + err = tsc2007_alloc(client, &ts, &input_dev); + if (err < 0) + return err; ts->client = client; ts->irq = client->irq; ts->input = input_dev; init_waitqueue_head(&ts->wait); + mutex_init(&ts->mlock); snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&client->dev)); @@ -543,6 +702,7 @@ static int tsc2007_probe(struct i2c_client *client, if (err < 0) { dev_err(&client->dev, "Failed to setup chip: %d\n", err); + tsc2007_iio_device_unregister(ts); return err; /* usually, chip does not respond */ } @@ -556,6 +716,14 @@ static int tsc2007_probe(struct i2c_client *client, return 0; } +static int tsc2007_remove(struct i2c_client *client) +{ + struct tsc2007 *ts = i2c_get_clientdata(client); + input_unregister_device(ts->input); + tsc2007_iio_device_unregister(ts); + return 0; +} + static const struct i2c_device_id tsc2007_idtable[] = { { "tsc2007", 0 }, { } @@ -578,6 +746,7 @@ static struct i2c_driver tsc2007_driver = { }, .id_table = tsc2007_idtable, .probe = tsc2007_probe, + .remove = tsc2007_remove, }; module_i2c_driver(tsc2007_driver);