Input: cyapa - switch to using managed resources

Use of managed resources simplifies error handling and device removal code.

Signed-off-by: Dudley Du <dudl@cypress.com>
[Dmitry: added open/close methods so cyapa_remove is no longer needed.]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 105 insertions, 79 deletions

diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
index 1d978c7289b4..c84a9ebeb2ff 100644
--- a/drivers/input/mouse/cyapa.c
+++ b/drivers/input/mouse/cyapa.c
@@ -577,10 +577,13 @@ static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
         power = ret & ~PWR_MODE_MASK;
         power |= power_mode & PWR_MODE_MASK;
         ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
-        if (ret < 0)
+        if (ret < 0) {
                 dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
                         power_mode, ret);
-        return ret;
+                return ret;
+        }
+
+        return 0;
 }
 
 static int cyapa_get_query_data(struct cyapa *cyapa)
@@ -753,16 +756,40 @@ static u8 cyapa_check_adapter_functionality(struct i2c_client *client)
         return ret;
 }
 
+static int cyapa_open(struct input_dev *input)
+{
+        struct cyapa *cyapa = input_get_drvdata(input);
+        struct i2c_client *client = cyapa->client;
+        int error;
+
+        error = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+        if (error) {
+                dev_err(&client->dev, "set active power failed: %d\n", error);
+                return error;
+        }
+
+        enable_irq(client->irq);
+        return 0;
+}
+
+static void cyapa_close(struct input_dev *input)
+{
+        struct cyapa *cyapa = input_get_drvdata(input);
+
+        disable_irq(cyapa->client->irq);
+        cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
+}
+
 static int cyapa_create_input_dev(struct cyapa *cyapa)
 {
         struct device *dev = &cyapa->client->dev;
-        int ret;
         struct input_dev *input;
+        int error;
 
         if (!cyapa->physical_size_x || !cyapa->physical_size_y)
                 return -EINVAL;
 
-        input = cyapa->input = input_allocate_device();
+        input = devm_input_allocate_device(dev);
         if (!input) {
                 dev_err(dev, "allocate memory for input device failed\n");
                 return -ENOMEM;
@@ -775,6 +802,9 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
         input->id.product = 0;  /* means any product in eventcomm. */
         input->dev.parent = &cyapa->client->dev;
 
+        input->open = cyapa_open;
+        input->close = cyapa_close;
+
         input_set_drvdata(input, cyapa);
 
         __set_bit(EV_ABS, input->evbit);
@@ -802,34 +832,24 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
                 __set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
 
         /* handle pointer emulation and unused slots in core */
-        ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
-                                  INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
-        if (ret) {
-                dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
-                goto err_free_device;
+        error = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
+                                    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
+        if (error) {
+                dev_err(dev, "failed to initialize MT slots: %d\n", error);
+                return error;
         }
 
-        /* Register the device in input subsystem */
-        ret = input_register_device(input);
-        if (ret) {
-                dev_err(dev, "input device register failed, %d\n", ret);
-                goto err_free_device;
-        }
+        cyapa->input = input;
         return 0;
-
-err_free_device:
-        input_free_device(input);
-        cyapa->input = NULL;
-        return ret;
 }
 
 static int cyapa_probe(struct i2c_client *client,
                        const struct i2c_device_id *dev_id)
 {
-        int ret;
-        u8 adapter_func;
-        struct cyapa *cyapa;
         struct device *dev = &client->dev;
+        struct cyapa *cyapa;
+        u8 adapter_func;
+        int error;
 
         adapter_func = cyapa_check_adapter_functionality(client);
         if (adapter_func == CYAPA_ADAPTER_FUNC_NONE) {
@@ -837,11 +857,9 @@ static int cyapa_probe(struct i2c_client *client,
                 return -EIO;
         }
 
-        cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
-        if (!cyapa) {
-                dev_err(dev, "allocate memory for cyapa failed\n");
+        cyapa = devm_kzalloc(dev, sizeof(struct cyapa), GFP_KERNEL);
+        if (!cyapa)
                 return -ENOMEM;
-        }
 
         cyapa->gen = CYAPA_GEN3;
         cyapa->client = client;
@@ -852,66 +870,61 @@ static int cyapa_probe(struct i2c_client *client,
         /* i2c isn't supported, use smbus */
         if (adapter_func == CYAPA_ADAPTER_FUNC_SMBUS)
                 cyapa->smbus = true;
+
         cyapa->state = CYAPA_STATE_NO_DEVICE;
-        ret = cyapa_check_is_operational(cyapa);
-        if (ret) {
-                dev_err(dev, "device not operational, %d\n", ret);
-                goto err_mem_free;
-        }
 
-        ret = cyapa_create_input_dev(cyapa);
-        if (ret) {
-                dev_err(dev, "create input_dev instance failed, %d\n", ret);
-                goto err_mem_free;
+        error = cyapa_check_is_operational(cyapa);
+        if (error) {
+                dev_err(dev, "device not operational, %d\n", error);
+                return error;
         }
 
-        ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
-        if (ret) {
-                dev_err(dev, "set active power failed, %d\n", ret);
-                goto err_unregister_device;
+        /* Power down the device until we need it */
+        error = cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
+        if (error) {
+                dev_err(dev, "failed to quiesce the device: %d\n", error);
+                return error;
         }
 
-        cyapa->irq = client->irq;
-        ret = request_threaded_irq(cyapa->irq,
-                                   NULL,
-                                   cyapa_irq,
-                                   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
-                                   "cyapa",
-                                   cyapa);
-        if (ret) {
-                dev_err(dev, "IRQ request failed: %d\n, ", ret);
-                goto err_unregister_device;
+        error = cyapa_create_input_dev(cyapa);
+        if (error)
+                return error;
+
+        error = devm_request_threaded_irq(dev, client->irq,
+                                          NULL, cyapa_irq,
+                                          IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                                          "cyapa", cyapa);
+        if (error) {
+                dev_err(dev, "IRQ request failed: %d\n, ", error);
+                return error;
         }
 
-        return 0;
-
-err_unregister_device:
-        input_unregister_device(cyapa->input);
-err_mem_free:
-        kfree(cyapa);
+        /* Disable IRQ until the device is opened */
+        disable_irq(client->irq);
 
-        return ret;
-}
-
-static int cyapa_remove(struct i2c_client *client)
-{
-        struct cyapa *cyapa = i2c_get_clientdata(client);
-
-        free_irq(cyapa->irq, cyapa);
-        input_unregister_device(cyapa->input);
-        cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
-        kfree(cyapa);
+        /* Register the device in input subsystem */
+        error = input_register_device(cyapa->input);
+        if (error) {
+                dev_err(dev, "failed to register input device: %d\n", error);
+                return error;
+        }
 
         return 0;
 }
 
 static int __maybe_unused cyapa_suspend(struct device *dev)
 {
-        int ret;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct cyapa *cyapa = i2c_get_clientdata(client);
+        struct input_dev *input = cyapa->input;
         u8 power_mode;
-        struct cyapa *cyapa = dev_get_drvdata(dev);
+        int error;
+
+        error = mutex_lock_interruptible(&input->mutex);
+        if (error)
+                return error;
 
-        disable_irq(cyapa->irq);
+        disable_irq(client->irq);
 
         /*
          * Set trackpad device to idle mode if wakeup is allowed,
@@ -919,28 +932,42 @@ static int __maybe_unused cyapa_suspend(struct device *dev)
          */
         power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
                                             : PWR_MODE_OFF;
-        ret = cyapa_set_power_mode(cyapa, power_mode);
-        if (ret < 0)
-                dev_err(dev, "set power mode failed, %d\n", ret);
+        error = cyapa_set_power_mode(cyapa, power_mode);
+        if (error)
+                dev_err(dev, "resume: set power mode to %d failed: %d\n",
+                         power_mode, error);
 
         if (device_may_wakeup(dev))
                 cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
+
+        mutex_unlock(&input->mutex);
+
         return 0;
 }
 
 static int __maybe_unused cyapa_resume(struct device *dev)
 {
-        int ret;
-        struct cyapa *cyapa = dev_get_drvdata(dev);
+        struct i2c_client *client = to_i2c_client(dev);
+        struct cyapa *cyapa = i2c_get_clientdata(client);
+        struct input_dev *input = cyapa->input;
+        u8 power_mode;
+        int error;
+
+        mutex_lock(&input->mutex);
 
         if (device_may_wakeup(dev) && cyapa->irq_wake)
                 disable_irq_wake(cyapa->irq);
 
-        ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
-        if (ret)
-                dev_warn(dev, "resume active power failed, %d\n", ret);
+        power_mode = input->users ? PWR_MODE_FULL_ACTIVE : PWR_MODE_OFF;
+        error = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+        if (error)
+                dev_warn(dev, "resume: set power mode to %d failed: %d\n",
+                         power_mode, error);
 
         enable_irq(cyapa->irq);
+
+        mutex_unlock(&input->mutex);
+
         return 0;
 }
 
@@ -960,7 +987,6 @@ static struct i2c_driver cyapa_driver = {
         },
 
         .probe = cyapa_probe,
-        .remove = cyapa_remove,
         .id_table = cyapa_id_table,
 };