diff options
| -rw-r--r-- | Documentation/devicetree/bindings/input/elants_i2c.txt | 3 | ||||
| -rw-r--r-- | drivers/input/touchscreen/elants_i2c.c | 184 |
2 files changed, 165 insertions, 22 deletions
diff --git a/Documentation/devicetree/bindings/input/elants_i2c.txt b/Documentation/devicetree/bindings/input/elants_i2c.txt index a765232..8a71038 100644 --- a/Documentation/devicetree/bindings/input/elants_i2c.txt +++ b/Documentation/devicetree/bindings/input/elants_i2c.txt @@ -13,6 +13,9 @@ Optional properties: - pinctrl-names: should be "default" (see pinctrl binding [1]). - pinctrl-0: a phandle pointing to the pin settings for the device (see pinctrl binding [1]). +- reset-gpios: reset gpio the chip is connected to. +- vcc33-supply: a phandle for the regulator supplying 3.3V power. +- vccio-supply: a phandle for the regulator supplying IO power. [0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt [1]: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c index 42e43f1..1912265 100644 --- a/drivers/input/touchscreen/elants_i2c.c +++ b/drivers/input/touchscreen/elants_i2c.c @@ -38,6 +38,8 @@ #include <linux/input/mt.h> #include <linux/acpi.h> #include <linux/of.h> +#include <linux/gpio/consumer.h> +#include <linux/regulator/consumer.h> #include <asm/unaligned.h> /* Device, Driver information */ @@ -102,6 +104,9 @@ /* calibration timeout definition */ #define ELAN_CALI_TIMEOUT_MSEC 10000 +#define ELAN_POWERON_DELAY_USEC 500 +#define ELAN_RESET_DELAY_MSEC 20 + enum elants_state { ELAN_STATE_NORMAL, ELAN_WAIT_QUEUE_HEADER, @@ -118,6 +123,10 @@ struct elants_data { struct i2c_client *client; struct input_dev *input; + struct regulator *vcc33; + struct regulator *vccio; + struct gpio_desc *reset_gpio; + u16 fw_version; u8 test_version; u8 solution_version; @@ -141,6 +150,7 @@ struct elants_data { u8 buf[MAX_PACKET_SIZE]; bool wake_irq_enabled; + bool keep_power_in_suspend; }; static int elants_i2c_send(struct i2c_client *client, @@ -1058,6 +1068,67 @@ static void elants_i2c_remove_sysfs_group(void *_data) sysfs_remove_group(&ts->client->dev.kobj, &elants_attribute_group); } +static int elants_i2c_power_on(struct elants_data *ts) +{ + int error; + + /* + * If we do not have reset gpio assume platform firmware + * controls regulators and does power them on for us. + */ + if (IS_ERR_OR_NULL(ts->reset_gpio)) + return 0; + + gpiod_set_value_cansleep(ts->reset_gpio, 1); + + error = regulator_enable(ts->vcc33); + if (error) { + dev_err(&ts->client->dev, + "failed to enable vcc33 regulator: %d\n", + error); + goto release_reset_gpio; + } + + error = regulator_enable(ts->vccio); + if (error) { + dev_err(&ts->client->dev, + "failed to enable vccio regulator: %d\n", + error); + regulator_disable(ts->vcc33); + goto release_reset_gpio; + } + + /* + * We need to wait a bit after powering on controller before + * we are allowed to release reset GPIO. + */ + udelay(ELAN_POWERON_DELAY_USEC); + +release_reset_gpio: + gpiod_set_value_cansleep(ts->reset_gpio, 0); + if (error) + return error; + + msleep(ELAN_RESET_DELAY_MSEC); + + return 0; +} + +static void elants_i2c_power_off(void *_data) +{ + struct elants_data *ts = _data; + + if (!IS_ERR_OR_NULL(ts->reset_gpio)) { + /* + * Activate reset gpio to prevent leakage through the + * pin once we shut off power to the controller. + */ + gpiod_set_value_cansleep(ts->reset_gpio, 1); + regulator_disable(ts->vccio); + regulator_disable(ts->vcc33); + } +} + static int elants_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -1072,13 +1143,6 @@ static int elants_i2c_probe(struct i2c_client *client, return -ENXIO; } - /* Make sure there is something at this address */ - if (i2c_smbus_xfer(client->adapter, client->addr, 0, - I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) { - dev_err(&client->dev, "nothing at this address\n"); - return -ENXIO; - } - ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL); if (!ts) return -ENOMEM; @@ -1089,6 +1153,70 @@ static int elants_i2c_probe(struct i2c_client *client, ts->client = client; i2c_set_clientdata(client, ts); + ts->vcc33 = devm_regulator_get(&client->dev, "vcc33"); + if (IS_ERR(ts->vcc33)) { + error = PTR_ERR(ts->vcc33); + if (error != -EPROBE_DEFER) + dev_err(&client->dev, + "Failed to get 'vcc33' regulator: %d\n", + error); + return error; + } + + ts->vccio = devm_regulator_get(&client->dev, "vccio"); + if (IS_ERR(ts->vccio)) { + error = PTR_ERR(ts->vccio); + if (error != -EPROBE_DEFER) + dev_err(&client->dev, + "Failed to get 'vccio' regulator: %d\n", + error); + return error; + } + + ts->reset_gpio = devm_gpiod_get(&client->dev, "reset"); + if (IS_ERR(ts->reset_gpio)) { + error = PTR_ERR(ts->reset_gpio); + + if (error == -EPROBE_DEFER) + return error; + + if (error != -ENOENT && error != -ENOSYS) { + dev_err(&client->dev, + "failed to get reset gpio: %d\n", + error); + return error; + } + + ts->keep_power_in_suspend = true; + } else { + error = gpiod_direction_output(ts->reset_gpio, 0); + if (error) { + dev_err(&client->dev, + "failed to configure reset gpio as output: %d\n", + error); + return error; + } + } + + error = elants_i2c_power_on(ts); + if (error) + return error; + + error = devm_add_action(&client->dev, elants_i2c_power_off, ts); + if (error) { + dev_err(&client->dev, + "failed to install power off action: %d\n", error); + elants_i2c_power_off(ts); + return error; + } + + /* Make sure there is something at this address */ + if (i2c_smbus_xfer(client->adapter, client->addr, 0, + I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) { + dev_err(&client->dev, "nothing at this address\n"); + return -ENXIO; + } + error = elants_i2c_initialize(ts); if (error) { dev_err(&client->dev, "failed to initialize: %d\n", error); @@ -1196,17 +1324,23 @@ static int __maybe_unused elants_i2c_suspend(struct device *dev) disable_irq(client->irq); - for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) { - error = elants_i2c_send(client, set_sleep_cmd, - sizeof(set_sleep_cmd)); - if (!error) - break; + if (device_may_wakeup(dev) || ts->keep_power_in_suspend) { + for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) { + error = elants_i2c_send(client, set_sleep_cmd, + sizeof(set_sleep_cmd)); + if (!error) + break; - dev_err(&client->dev, "suspend command failed: %d\n", error); - } + dev_err(&client->dev, + "suspend command failed: %d\n", error); + } - if (device_may_wakeup(dev)) - ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0); + if (device_may_wakeup(dev)) + ts->wake_irq_enabled = + (enable_irq_wake(client->irq) == 0); + } else { + elants_i2c_power_off(ts); + } return 0; } @@ -1222,13 +1356,19 @@ static int __maybe_unused elants_i2c_resume(struct device *dev) if (device_may_wakeup(dev) && ts->wake_irq_enabled) disable_irq_wake(client->irq); - for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) { - error = elants_i2c_send(client, set_active_cmd, - sizeof(set_active_cmd)); - if (!error) - break; + if (ts->keep_power_in_suspend) { + for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) { + error = elants_i2c_send(client, set_active_cmd, + sizeof(set_active_cmd)); + if (!error) + break; - dev_err(&client->dev, "resume command failed: %d\n", error); + dev_err(&client->dev, + "resume command failed: %d\n", error); + } + } else { + elants_i2c_power_on(ts); + elants_i2c_initialize(ts); } ts->state = ELAN_STATE_NORMAL; |