From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E01DC433E0 for ; Wed, 20 May 2020 16:53:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 52B8420709 for ; Wed, 20 May 2020 16:53:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726837AbgETQxr (ORCPT ); Wed, 20 May 2020 12:53:47 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:39474 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726510AbgETQxr (ORCPT ); Wed, 20 May 2020 12:53:47 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 5E27A2A0632 Subject: Re: [PATCHv3 4/5] Input: EXC3000: Add support to query model and fw_version To: Sebastian Reichel , Dmitry Torokhov , Ahmet Inan , Martin Fuzzey Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com References: <20200520153936.46869-1-sebastian.reichel@collabora.com> <20200520153936.46869-5-sebastian.reichel@collabora.com> From: Enric Balletbo i Serra Message-ID: Date: Wed, 20 May 2020 18:53:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200520153936.46869-5-sebastian.reichel@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sebastian, On 20/5/20 17:39, Sebastian Reichel wrote: > Expose model and fw_version via sysfs. Also query the model > in probe to make sure, that the I2C communication with the > device works before successfully probing the driver. > > This is a bit complicated, since EETI devices do not have > a sync interface. Sending the commands and directly reading > does not work. Sending the command and waiting for some time > is also not an option, since there might be touch events in > the mean time. > > Last but not least we do not cache the results, since this > interface can be used to check the I2C communication is still > working as expected. > > Signed-off-by: Sebastian Reichel I went through the code and understood the reasoning to implement that way, if it helps: Reviewed-by: Enric Balletbo i Serra > --- > .../ABI/testing/sysfs-driver-input-exc3000 | 15 ++ > drivers/input/touchscreen/exc3000.c | 145 +++++++++++++++++- > 2 files changed, 159 insertions(+), 1 deletion(-) > create mode 100644 Documentation/ABI/testing/sysfs-driver-input-exc3000 > > diff --git a/Documentation/ABI/testing/sysfs-driver-input-exc3000 b/Documentation/ABI/testing/sysfs-driver-input-exc3000 > new file mode 100644 > index 000000000000..d79da4f869af > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-driver-input-exc3000 > @@ -0,0 +1,15 @@ > +What: /sys/class/input/inputX/fw_version > +Date: May 2020 > +Contact: linux-input@vger.kernel.org > +Description: Reports the firmware version provided by the touchscreen, for example "00_T6" on a EXC80H60 > + > + Access: Read > + Valid values: Represented as string > + > +What: /sys/class/input/inputX/model > +Date: May 2020 > +Contact: linux-input@vger.kernel.org > +Description: Reports the model identification provided by the touchscreen, for example "Orion_1320" on a EXC80H60 > + > + Access: Read > + Valid values: Represented as string > diff --git a/drivers/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c > index b497bd2ae41d..b5a3bbb63504 100644 > --- a/drivers/input/touchscreen/exc3000.c > +++ b/drivers/input/touchscreen/exc3000.c > @@ -25,6 +25,9 @@ > #define EXC3000_LEN_FRAME 66 > #define EXC3000_LEN_POINT 10 > > +#define EXC3000_LEN_MODEL_NAME 16 > +#define EXC3000_LEN_FW_VERSION 16 > + > #define EXC3000_MT1_EVENT 0x06 > #define EXC3000_MT2_EVENT 0x18 > > @@ -65,6 +68,11 @@ struct exc3000_data { > struct touchscreen_properties prop; > struct timer_list timer; > u8 buf[2 * EXC3000_LEN_FRAME]; > + struct completion wait_event; > + struct mutex query_lock; > + int query_result; > + char model[EXC3000_LEN_MODEL_NAME]; > + char fw_version[EXC3000_LEN_FW_VERSION]; > }; > > static void exc3000_report_slots(struct input_dev *input, > @@ -150,6 +158,28 @@ static int exc3000_read_data(struct exc3000_data *data, > return 0; > } > > +static int exc3000_query_interrupt(struct exc3000_data *data) > +{ > + u8 *buf = data->buf; > + int err; > + > + err = i2c_master_recv(data->client, buf, EXC3000_LEN_FRAME); > + if (err < 0) > + return err; > + > + if (buf[0] != 0x42) > + return -EPROTO; > + > + if (buf[4] == 'E') > + strlcpy(data->model, buf+5, sizeof(data->model)); > + else if (buf[4] == 'D') > + strlcpy(data->fw_version, buf+5, sizeof(data->fw_version)); > + else > + return -EPROTO; > + > + return 0; > +} > + > static irqreturn_t exc3000_interrupt(int irq, void *dev_id) > { > struct exc3000_data *data = dev_id; > @@ -158,6 +188,12 @@ static irqreturn_t exc3000_interrupt(int irq, void *dev_id) > int slots, total_slots; > int error; > > + if (mutex_is_locked(&data->query_lock)) { > + data->query_result = exc3000_query_interrupt(data); > + complete(&data->wait_event); > + goto out; > + } > + > error = exc3000_read_data(data, buf, &total_slots); > if (error) { > /* Schedule a timer to release "stuck" contacts */ > @@ -185,11 +221,94 @@ static irqreturn_t exc3000_interrupt(int irq, void *dev_id) > return IRQ_HANDLED; > } > > +static ssize_t fw_version_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct exc3000_data *data = dev_get_drvdata(dev); > + static const u8 request[68] = { > + 0x67, 0x00, 0x42, 0x00, 0x03, 0x01, 'D', 0x00 > + }; > + struct i2c_client *client = data->client; > + int err; > + > + mutex_lock(&data->query_lock); > + > + data->query_result = -ETIMEDOUT; > + reinit_completion(&data->wait_event); > + > + err = i2c_master_send(client, request, sizeof(request)); > + if (err < 0) { > + mutex_unlock(&data->query_lock); > + return err; > + } > + > + wait_for_completion_interruptible_timeout(&data->wait_event, 1*HZ); > + mutex_unlock(&data->query_lock); > + > + if (data->query_result < 0) > + return data->query_result; > + > + return sprintf(buf, "%s\n", data->fw_version); > +} > +static DEVICE_ATTR_RO(fw_version); > + > +static ssize_t exc3000_get_model(struct exc3000_data *data) > +{ > + static const u8 request[68] = { > + 0x67, 0x00, 0x42, 0x00, 0x03, 0x01, 'E', 0x00 > + }; > + struct i2c_client *client = data->client; > + int err; > + > + mutex_lock(&data->query_lock); > + data->query_result = -ETIMEDOUT; > + reinit_completion(&data->wait_event); > + > + err = i2c_master_send(client, request, sizeof(request)); > + if (err < 0) { > + mutex_unlock(&data->query_lock); > + return err; > + } > + > + wait_for_completion_interruptible_timeout(&data->wait_event, 1 * HZ); > + mutex_unlock(&data->query_lock); > + > + return data->query_result; > +} > + > +static ssize_t model_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct exc3000_data *data = dev_get_drvdata(dev); > + int err = exc3000_get_model(data); > + > + if (err < 0) > + return err; > + > + return sprintf(buf, "%s\n", data->model); > +} > +static DEVICE_ATTR_RO(model); > + > +static struct attribute *sysfs_attrs[] = { > + &dev_attr_fw_version.attr, > + &dev_attr_model.attr, > + NULL > +}; > + > +static struct attribute_group exc3000_attribute_group = { > + .attrs = sysfs_attrs > +}; > + > +static const struct attribute_group *exc3000_attribute_groups[] = { > + &exc3000_attribute_group, > + NULL > +}; > + > static int exc3000_probe(struct i2c_client *client) > { > struct exc3000_data *data; > struct input_dev *input; > - int error, max_xy; > + int error, max_xy, retry; > > data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); > if (!data) > @@ -203,15 +322,19 @@ static int exc3000_probe(struct i2c_client *client) > data->info = &exc3000_info[eeti_dev_id]; > } > timer_setup(&data->timer, exc3000_timer, 0); > + init_completion(&data->wait_event); > + mutex_init(&data->query_lock); > > input = devm_input_allocate_device(&client->dev); > if (!input) > return -ENOMEM; > > data->input = input; > + input_set_drvdata(input, data); > > input->name = data->info->name; > input->id.bustype = BUS_I2C; > + input->dev.groups = exc3000_attribute_groups; > > max_xy = data->info->max_xy; > input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_xy, 0, 0); > @@ -234,6 +357,26 @@ static int exc3000_probe(struct i2c_client *client) > if (error) > return error; > > + /* > + * I²C does not have built-in recovery, so retry on failure. This ensures, > + * that the device probe will not fail for temporary issues on the bus. > + * This is not needed for the sysfs calls (userspace will receive the error > + * code and can start another query) and cannot be done for touch events > + * (but that only means loosing one or two touch events anyways). > + */ > + for (retry = 0; retry < 3; ++retry) { > + error = exc3000_get_model(data); > + if (!error) > + break; > + dev_warn(&client->dev, "Retry %d get EETI EXC3000 model: %d\n", > + retry + 1, error); > + } > + > + if (error) > + return error; > + > + dev_dbg(&client->dev, "TS Model: %s", data->model); > + > return 0; > } > >