Re: [PATCH 04/15] drivers: thermal: tsens: Add debugfs support

From: Amit Kucheria
Date: Mon Aug 19 2019 - 03:58:37 EST


On Sat, Aug 17, 2019 at 9:37 AM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
>
> Quoting Amit Kucheria (2019-07-25 15:18:39)
> > Dump some basic version info and sensor details into debugfs
> >
>
> Maybe you can put some sample output in the commit text.

Will do.

> > Signed-off-by: Amit Kucheria <amit.kucheria@xxxxxxxxxx>
> > ---
> > drivers/thermal/qcom/tsens-common.c | 85 +++++++++++++++++++++++++++++
> > drivers/thermal/qcom/tsens.c | 2 +
> > drivers/thermal/qcom/tsens.h | 6 ++
> > 3 files changed, 93 insertions(+)
> >
> > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > index 7437bfe196e5..7ab2e740a1da 100644
> > --- a/drivers/thermal/qcom/tsens-common.c
> > +++ b/drivers/thermal/qcom/tsens-common.c
> > @@ -3,6 +3,7 @@
> > * Copyright (c) 2015, The Linux Foundation. All rights reserved.
> > */
> >
> > +#include <linux/debugfs.h>
> > #include <linux/err.h>
> > #include <linux/io.h>
> > #include <linux/nvmem-consumer.h>
> > @@ -139,6 +140,79 @@ int get_temp_common(struct tsens_sensor *s, int *temp)
> > return 0;
> > }
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +static int dbg_sensors_show(struct seq_file *s, void *data)
> > +{
> > + struct platform_device *pdev = s->private;
> > + struct tsens_priv *priv = platform_get_drvdata(pdev);
> > + int i;
> > +
> > + seq_printf(s, "max: %2d\nnum: %2d\n\n",
> > + priv->feat->max_sensors, priv->num_sensors);
> > +
> > + seq_puts(s, " id slope offset\n------------------------\n");
> > + for (i = 0; i < priv->num_sensors; i++) {
> > + seq_printf(s, "%8d%8d%8d\n", priv->sensor[i].hw_id,
>
> Does this not have spaces between the digits on purpose?

Nice catch. The 8-char width above hid the problem. Will add.

> > + priv->sensor[i].slope, priv->sensor[i].offset);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int dbg_version_show(struct seq_file *s, void *data)
> > +{
> > + struct platform_device *pdev = s->private;
> > + struct tsens_priv *priv = platform_get_drvdata(pdev);
> > + u32 maj_ver, min_ver, step_ver;
> > + int ret;
> > +
> > + if (tsens_ver(priv) > VER_0_1) {
> > + ret = regmap_field_read(priv->rf[VER_MAJOR], &maj_ver);
> > + if (ret)
> > + return ret;
> > + ret = regmap_field_read(priv->rf[VER_MINOR], &min_ver);
> > + if (ret)
> > + return ret;
> > + ret = regmap_field_read(priv->rf[VER_STEP], &step_ver);
> > + if (ret)
> > + return ret;
> > + seq_printf(s, "%d.%d.%d\n", maj_ver, min_ver, step_ver);
> > + } else {
> > + seq_puts(s, "0.1.0\n");
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +DEFINE_SHOW_ATTRIBUTE(dbg_version);
> > +DEFINE_SHOW_ATTRIBUTE(dbg_sensors);
> > +
> > +static void tsens_debug_init(struct platform_device *pdev)
> > +{
> > + struct tsens_priv *priv = platform_get_drvdata(pdev);
> > + struct dentry *root, *file;
> > +
> > + root = debugfs_lookup("tsens", NULL);
>
> Does this get created many times? Why doesn't tsens have a pointer to
> the root saved away somewhere globally?
>

I guess we could call the statement below to create the root dir and
save away the pointer. I was trying to avoid #ifdef CONFIG_DEBUG_FS in
init_common() and instead have all of it in a single function that
gets called once per instance of the tsens controller.

> > + if (!root)
> > + priv->debug_root = debugfs_create_dir("tsens", NULL);
> > + else
> > + priv->debug_root = root;
> > +
> > + file = debugfs_lookup("version", priv->debug_root);
> > + if (!file)
> > + debugfs_create_file("version", 0444, priv->debug_root,
> > + pdev, &dbg_version_fops);
> > +
> > + /* A directory for each instance of the TSENS IP */
> > + priv->debug = debugfs_create_dir(dev_name(&pdev->dev), priv->debug_root);
> > + debugfs_create_file("sensors", 0444, priv->debug, pdev, &dbg_sensors_fops);
> > +
> > + return;
> > +}