[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1422291516-24895-1-git-send-email-plaes@plaes.org>
Date: Mon, 26 Jan 2015 18:58:32 +0200
From: Priit Laes <plaes@...es.org>
To: unlisted-recipients:; (no To-header on input)
Cc: linux-sunxi@...glegroups.com, Priit Laes <plaes@...es.org>,
Maxime Ripard <maxime.ripard@...e-electrons.com>,
Hans de Goede <hdegoede@...hat.com>,
Dmitry Torokhov <dmitry.torokhov@...il.com>,
linux-api@...r.kernel.org (open list:ABI/API),
linux-arm-kernel@...ts.infradead.org (moderated list:ARM/Allwinner
A1X...), linux-kernel@...r.kernel.org (open list),
linux-input@...r.kernel.org (open list:SUN4I LOW RES ADC...)
Subject: [PATCH] arm: sunxi: input: RFC: Add sysfs voltage for sun4i-lradc driver
---
.../ABI/testing/sysfs-driver-input-sun4i-lradc | 4 ++
drivers/input/keyboard/sun4i-lradc-keys.c | 49 +++++++++++++++++-----
2 files changed, 43 insertions(+), 10 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-driver-input-sun4i-lradc
diff --git a/Documentation/ABI/testing/sysfs-driver-input-sun4i-lradc b/Documentation/ABI/testing/sysfs-driver-input-sun4i-lradc
new file mode 100644
index 0000000..e4e6448
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-input-sun4i-lradc
@@ -0,0 +1,4 @@
+What: /sys/class/input/input(x)/device/voltage
+Date: February 2015
+Contact: Priit Laes <plaes@...es.org>
+Description: ADC output voltage in microvolts or 0 if device is not opened.
diff --git a/drivers/input/keyboard/sun4i-lradc-keys.c b/drivers/input/keyboard/sun4i-lradc-keys.c
index cc8f7dd..c0ab8ec 100644
--- a/drivers/input/keyboard/sun4i-lradc-keys.c
+++ b/drivers/input/keyboard/sun4i-lradc-keys.c
@@ -79,10 +79,27 @@ struct sun4i_lradc_data {
u32 vref;
};
+static u32 sun4i_lradc_read_voltage(struct sun4i_lradc_data *lradc)
+{
+ u32 val = readl(lradc->base + LRADC_DATA0) & 0x3f;
+ return val * lradc->vref / 63;
+};
+
+static ssize_t
+sun4i_lradc_dev_voltage_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct sun4i_lradc_data *lradc = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", sun4i_lradc_read_voltage(lradc));
+}
+
+static const DEVICE_ATTR(voltage, S_IRUGO, sun4i_lradc_dev_voltage_show, NULL);
+
static irqreturn_t sun4i_lradc_irq(int irq, void *dev_id)
{
struct sun4i_lradc_data *lradc = dev_id;
- u32 i, ints, val, voltage, diff, keycode = 0, closest = 0xffffffff;
+ u32 i, ints, voltage, diff, keycode = 0, closest = 0xffffffff;
ints = readl(lradc->base + LRADC_INTS);
@@ -97,8 +114,7 @@ static irqreturn_t sun4i_lradc_irq(int irq, void *dev_id)
}
if ((ints & CHAN0_KEYDOWN_IRQ) && lradc->chan0_keycode == 0) {
- val = readl(lradc->base + LRADC_DATA0) & 0x3f;
- voltage = val * lradc->vref / 63;
+ voltage = sun4i_lradc_read_voltage(lradc);
for (i = 0; i < lradc->chan0_map_count; i++) {
diff = abs(lradc->chan0_map[i].voltage - voltage);
@@ -156,7 +172,7 @@ static void sun4i_lradc_close(struct input_dev *dev)
}
static int sun4i_lradc_load_dt_keymap(struct device *dev,
- struct sun4i_lradc_data *lradc)
+ struct sun4i_lradc_data *lradc)
{
struct device_node *np, *pp;
int i;
@@ -168,8 +184,8 @@ static int sun4i_lradc_load_dt_keymap(struct device *dev,
lradc->chan0_map_count = of_get_child_count(np);
if (lradc->chan0_map_count == 0) {
- dev_err(dev, "keymap is missing in device tree\n");
- return -EINVAL;
+ dev_info(dev, "keymap is missing in device tree\n");
+ return 0;
}
lradc->chan0_map = devm_kmalloc_array(dev, lradc->chan0_map_count,
@@ -185,19 +201,19 @@ static int sun4i_lradc_load_dt_keymap(struct device *dev,
error = of_property_read_u32(pp, "channel", &channel);
if (error || channel != 0) {
- dev_err(dev, "%s: Inval channel prop\n", pp->name);
+ dev_err(dev, "%s: Invalid 'channel' property\n", pp->name);
return -EINVAL;
}
error = of_property_read_u32(pp, "voltage", &map->voltage);
if (error) {
- dev_err(dev, "%s: Inval voltage prop\n", pp->name);
+ dev_err(dev, "%s: Invalid 'voltage' property\n", pp->name);
return -EINVAL;
}
error = of_property_read_u32(pp, "linux,code", &map->keycode);
if (error) {
- dev_err(dev, "%s: Inval linux,code prop\n", pp->name);
+ dev_err(dev, "%s: Invalid 'linux,code' property\n", pp->name);
return -EINVAL;
}
@@ -257,14 +273,26 @@ static int sun4i_lradc_probe(struct platform_device *pdev)
if (error)
return error;
- error = input_register_device(lradc->input);
+ error = device_create_file(dev, &dev_attr_voltage);
if (error)
return error;
+ error = input_register_device(lradc->input);
+ if (error) {
+ device_remove_file(&pdev->dev, &dev_attr_voltage);
+ return error;
+ }
+
platform_set_drvdata(pdev, lradc);
return 0;
}
+static int sun4i_lradc_remove(struct platform_device *pdev)
+{
+ device_remove_file(&pdev->dev, &dev_attr_voltage);
+ return 0;
+}
+
static const struct of_device_id sun4i_lradc_of_match[] = {
{ .compatible = "allwinner,sun4i-a10-lradc-keys", },
{ /* sentinel */ }
@@ -277,6 +305,7 @@ static struct platform_driver sun4i_lradc_driver = {
.of_match_table = of_match_ptr(sun4i_lradc_of_match),
},
.probe = sun4i_lradc_probe,
+ .remove = sun4i_lradc_remove,
};
module_platform_driver(sun4i_lradc_driver);
--
2.2.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists