@@ -30,7 +30,6 @@
#define RMI4_PAGE_MASK 0xFF00
#define RMI_DEVICE_RESET_CMD 0x01
-#define DEFAULT_RESET_DELAY_MS 100
void rmi_free_function_list(struct rmi_device *rmi_dev)
{
@@ -16,6 +16,8 @@
#define SYNAPTICS_INPUT_DEVICE_NAME "Synaptics RMI4 Touch Sensor"
#define SYNAPTICS_VENDOR_ID 0x06cb
+#define DEFAULT_RESET_DELAY_MS 100
+
#define GROUP(_attrs) { \
.attrs = _attrs, \
}
@@ -4,6 +4,7 @@
* Copyright (c) 2011 Unixphere
*/
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/rmi.h>
#include <linux/of.h>
@@ -26,7 +27,9 @@
* @tx_buf_size: Size of the buffer
*
* @supplies: Array of voltage regulators
+ * @reset_gpio: Reference to the reset GPIO
* @startup_delay: Milliseconds to pause after powering up the regulators
+ * @reset_delay: Milliseconds to pause after resetting the device
*/
struct rmi_i2c_xport {
struct rmi_transport_dev xport;
@@ -39,7 +42,9 @@ struct rmi_i2c_xport {
size_t tx_buf_size;
struct regulator_bulk_data supplies[2];
+ struct gpio_desc *reset_gpio;
u32 startup_delay;
+ u32 reset_delay;
};
#define RMI_PAGE_SELECT_REGISTER 0xff
@@ -227,6 +232,15 @@ static int rmi_i2c_probe(struct i2c_client *client)
return -ENODEV;
}
+ rmi_i2c->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(rmi_i2c->reset_gpio)) {
+ error = PTR_ERR(rmi_i2c->reset_gpio);
+ dev_err(&client->dev, "failed to get reset GPIO: %d\n", error);
+ return error;
+ }
+ gpiod_set_consumer_name(rmi_i2c->reset_gpio, "rmi4 reset");
+
rmi_i2c->supplies[0].supply = "vdd";
rmi_i2c->supplies[1].supply = "vio";
error = devm_regulator_bulk_get(&client->dev,
@@ -251,6 +265,15 @@ static int rmi_i2c_probe(struct i2c_client *client)
msleep(rmi_i2c->startup_delay);
+ if (rmi_i2c->reset_gpio) {
+ of_property_read_u32(client->dev.of_node, "syna,reset-delay-ms",
+ &rmi_i2c->reset_delay);
+ gpiod_set_value_cansleep(rmi_i2c->reset_gpio, 1);
+ usleep_range(10000, 20000);
+ gpiod_set_value_cansleep(rmi_i2c->reset_gpio, 0);
+ msleep(rmi_i2c->reset_delay ?: DEFAULT_RESET_DELAY_MS);
+ }
+
rmi_i2c->client = client;
mutex_init(&rmi_i2c->page_mutex);
Implement reset GPIO handling logic for the rmi_i2c driver. This logic is required for some mobile devices to successfully initialize the touch controller. The timings for the assertion of the reset GPIO were derived from the GPLv2+ licensed synaptics-dsx-v2.1 vendor driver release and research I conducted into downstream device tree sources. Values of 10ms to 20ms are commonly found. Tested-On: Motorola Moto G5 Plus (XT1685 "potter") Signed-off-by: Felix Kaechele <felix@kaechele.ca> --- drivers/input/rmi4/rmi_driver.c | 1 - drivers/input/rmi4/rmi_driver.h | 2 ++ drivers/input/rmi4/rmi_i2c.c | 23 +++++++++++++++++++++++ 3 files changed, 25 insertions(+), 1 deletion(-)