Add reset GPIO support to the generic i2c-hid-of driver
This is necessary to make the Wacom digitizer on the Lenovo Yoga Book 1
(yb1-x90f/l) work and this will also allow consolidating the 2 specialized
i2c-hid-of-elan.c and i2c-hid-of-goodix.c drivers into the generic
i2c-hid-of driver.
For now the new "post-reset-deassert-delay-ms" property is only used on
x86/ACPI (non devicetree) devs. IOW it is not used in actual devicetree
files and the same goes for the reset GPIO. The devicetree-bindings
maintainers have requested properties like these to not be added to
the devicetree-bindings, so the new property + GPIO are deliberately
not added to the existing devicetree-bindings.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/hid/i2c-hid/i2c-hid-of.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/hid/i2c-hid/i2c-hid-of.c b/drivers/hid/i2c-hid/i2c-hid-of.c
index 385f7460e03c..d0289afa57dc 100644
--- a/drivers/hid/i2c-hid/i2c-hid-of.c
+++ b/drivers/hid/i2c-hid/i2c-hid-of.c
@@ -21,6 +21,7 @@
#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/gpio/consumer.h>
#include <linux/hid.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
@@ -35,8 +36,10 @@ struct i2c_hid_of {
struct i2chid_ops ops;
struct i2c_client *client;
+ struct gpio_desc *reset_gpio;
struct regulator_bulk_data supplies[2];
int post_power_delay_ms;
+ int post_reset_delay_ms;
};
static int i2c_hid_of_power_up(struct i2chid_ops *ops)
@@ -55,6 +58,10 @@ static int i2c_hid_of_power_up(struct i2chid_ops *ops)
if (ihid_of->post_power_delay_ms)
msleep(ihid_of->post_power_delay_ms);
+ gpiod_set_value_cansleep(ihid_of->reset_gpio, 0);
+ if (ihid_of->post_reset_delay_ms)
+ msleep(ihid_of->post_reset_delay_ms);
+
return 0;
}
@@ -62,6 +69,7 @@ static void i2c_hid_of_power_down(struct i2chid_ops *ops)
{
struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
+ gpiod_set_value_cansleep(ihid_of->reset_gpio, 1);
regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies),
ihid_of->supplies);
}
@@ -96,6 +104,14 @@ static int i2c_hid_of_probe(struct i2c_client *client)
if (!device_property_read_u32(dev, "post-power-on-delay-ms", &val))
ihid_of->post_power_delay_ms = val;
+ if (!device_property_read_u32(dev, "post-reset-deassert-delay-ms", &val))
+ ihid_of->post_reset_delay_ms = val;
+
+ /* Start out with reset asserted */
+ ihid_of->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ihid_of->reset_gpio))
+ return PTR_ERR(ihid_of->reset_gpio);
+
ihid_of->supplies[0].supply = "vdd";
ihid_of->supplies[1].supply = "vddl";
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ihid_of->supplies),
--
2.39.1
