Hi Dmitry,
-----Original Message-----
From: Dmitry Torokhov [mailto:dmitry.torok...@gmail.com]
Sent: Wednesday, March 27, 2019 12:34 PM
To: KT Liao
Cc: linux-kernel@vger.kernel.org; linux-in...@vger.kernel.org;
ulrik.debie...@e2big.org; roger.whitta...@suse.com
Subject: Re: [PATCH] Input: elan_i2c - Add i2c_reset in sysfs for ELAN
touchpad recovery
Hi KT,
On Sat, Feb 02, 2019 at 03:54:56PM +0800, KT Liao wrote:
> Roger from SUSE reported the touchpad on Lenovo yoga2 crush sometimes.
> He found that rmmod/modprobe elan_i2c will recover the issue.
> He add the workaround on SUSE and solve the problem.
> Recently, the workaround fails in kernel 4.20 becasue IRQ mismatch.
> genirq: Flags mismatch irq 0. 00002002 (ELAN0600:00) vs. 00015a00
> (timer) I can't reproduce the issue in SUSE with the same kernel.
> And it's a 5 years old laptop, ELAN can't find the module for testing.
> Instead of IRQ debugging IRQ, I tried another approach.
> I added i2c_reset in sysfs to avoid IRQ requesting in probe.
How will users discover this flag? I do not think this is the best approach.
Can we detect that the touchpad firmware crashed from the kernel and reset
automatically?
Agree your better idea.
I will modify the driver for Roger's testing.
Will upstream after his testing.
Thanks.
>
> Signed-off-by: KT Liao <kt.l...@emc.com.tw>
> Acked-by: Roger Whittaker <roger.whitta...@suse.com>
> ---
> drivers/input/mouse/elan_i2c_core.c | 25 +++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff --git a/drivers/input/mouse/elan_i2c_core.c
> b/drivers/input/mouse/elan_i2c_core.c
> index 2690a4b..388b1f0 100644
> --- a/drivers/input/mouse/elan_i2c_core.c
> +++ b/drivers/input/mouse/elan_i2c_core.c
> @@ -670,6 +670,29 @@ static ssize_t calibrate_store(struct device *dev,
> return retval ?: count;
> }
>
> +static ssize_t i2c_reset_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count) {
> + struct i2c_client *client = to_i2c_client(dev);
> + struct elan_tp_data *data = i2c_get_clientdata(client);
> + int retval;
> +
> + retval = mutex_lock_interruptible(&data->sysfs_mutex);
> + if (retval)
> + return retval;
> +
> + disable_irq(client->irq);
> +
> + retval = elan_initialize(data);
> + if (retval)
> + dev_err(dev, "failed to re-initialize touchpad: %d\n",
retval);
> +
> + enable_irq(client->irq);
> + mutex_unlock(&data->sysfs_mutex);
> + return retval ?: count;
> +}
> +
> static ssize_t elan_sysfs_read_mode(struct device *dev,
> struct device_attribute *attr,
> char *buf)
> @@ -702,6 +725,7 @@ static DEVICE_ATTR(mode, S_IRUGO,
> elan_sysfs_read_mode, NULL); static DEVICE_ATTR(update_fw, S_IWUSR,
> NULL, elan_sysfs_update_fw);
>
> static DEVICE_ATTR_WO(calibrate);
> +static DEVICE_ATTR_WO(i2c_reset);
>
> static struct attribute *elan_sysfs_entries[] = {
> &dev_attr_product_id.attr,
> @@ -710,6 +734,7 @@ static struct attribute *elan_sysfs_entries[] = {
> &dev_attr_iap_version.attr,
> &dev_attr_fw_checksum.attr,
> &dev_attr_calibrate.attr,
> + &dev_attr_i2c_reset.attr,
> &dev_attr_mode.attr,
> &dev_attr_update_fw.attr,
> NULL,
> --
> 2.7.4
>
--
Dmitry
