2 files changed, 58 insertions, 21 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-hid-picolcd b/Documentation/ABI/testing/sysfs-driver-hid-picolcd
index 14f52d70621..08579e7e1e8 100644
--- a/Documentation/ABI/testing/sysfs-driver-hid-picolcd
+++ b/Documentation/ABI/testing/sysfs-driver-hid-picolcd
@@ -8,12 +8,21 @@ Description:	Make it possible to switch the PicoLCD device between LCD
                 enclosed in brackets ('[' and ']')
 
                 Writing: causes operation mode switch. Permitted values are
-                the non-active mode names listed when read, optionally followed
-                by a delay value expressed in ms.
+                the non-active mode names listed when read.
 
                 Note: when switching mode the current PicoLCD HID device gets
-                disconnected and reconnects after above delay (default value
-                is 5 seconds though this default should not be relied on).
+                disconnected and reconnects after above delay (see attribute
+                operation_mode_delay for its value).
+
+
+What:           /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/operation_mode_delay
+Date:           April 2010
+Contact:        Bruno Prémont <bonbons@linux-vserver.org>
+Description:    Delay PicoLCD waits before restarting in new mode when
+                operation_mode has changed.
+
+                Reading/Writing: It is expressed in ms and permitted range is
+                0..30000ms.
 
 
 What:           /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/fb_update_rate
diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index 6f71c60bf65..aa6f2e18d4a 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -177,6 +177,7 @@ struct picolcd_data {
         int addr_sz;
 #endif
         u8 version[2];
+        unsigned short opmode_delay;
         /* input stuff */
         u8 pressed_keys[2];
         struct input_dev *input_keys;
@@ -1270,8 +1271,7 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
         struct picolcd_data *data = dev_get_drvdata(dev);
         struct hid_report *report = NULL;
         size_t cnt = count;
-        int timeout = 5000;
-        unsigned u;
+        int timeout = data->opmode_delay;
         unsigned long flags;
 
         if (cnt >= 3 && strncmp("lcd", buf, 3) == 0) {
@@ -1288,20 +1288,10 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
         if (!report)
                 return -EINVAL;
 
-        while (cnt > 0 && (*buf == ' ' || *buf == '\t')) {
-                buf++;
-                cnt--;
-        }
         while (cnt > 0 && (buf[cnt-1] == '\n' || buf[cnt-1] == '\r'))
                 cnt--;
-        if (cnt > 0) {
-                if (sscanf(buf, "%u", &u) != 1)
-                        return -EINVAL;
-                if (u > 30000)
-                        return -EINVAL;
-                else
-                        timeout = u;
-        }
+        if (cnt != 0)
+                return -EINVAL;
 
         spin_lock_irqsave(&data->lock, flags);
         hid_set_field(report->field[0], 0, timeout & 0xff);
@@ -1314,6 +1304,34 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
 static DEVICE_ATTR(operation_mode, 0644, picolcd_operation_mode_show,
                 picolcd_operation_mode_store);
 
+/*
+ * The "operation_mode_delay" sysfs attribute
+ */
+static ssize_t picolcd_operation_mode_delay_show(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        struct picolcd_data *data = dev_get_drvdata(dev);
+
+        return snprintf(buf, PAGE_SIZE, "%hu\n", data->opmode_delay);
+}
+
+static ssize_t picolcd_operation_mode_delay_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct picolcd_data *data = dev_get_drvdata(dev);
+        unsigned u;
+        if (sscanf(buf, "%u", &u) != 1)
+                return -EINVAL;
+        if (u > 30000)
+                return -EINVAL;
+        else
+                data->opmode_delay = u;
+        return count;
+}
+
+static DEVICE_ATTR(operation_mode_delay, 0644, picolcd_operation_mode_delay_show,
+                picolcd_operation_mode_delay_store);
+
 
 #ifdef CONFIG_DEBUG_FS
 /*
@@ -2409,6 +2427,7 @@ static int picolcd_probe(struct hid_device *hdev,
         spin_lock_init(&data->lock);
         mutex_init(&data->mutex);
         data->hdev = hdev;
+        data->opmode_delay = 5000;
         if (hdev->product == USB_DEVICE_ID_PICOLCD_BOOTLOADER)
                 data->status |= PICOLCD_BOOTLOADER;
         hid_set_drvdata(hdev, data);
@@ -2436,24 +2455,32 @@ static int picolcd_probe(struct hid_device *hdev,
                 goto err_cleanup_hid_hw;
         }
 
-        error = device_create_file(&hdev->dev, &dev_attr_operation_mode);
+        error = device_create_file(&hdev->dev, &dev_attr_operation_mode_delay);
         if (error) {
                 dev_err(&hdev->dev, "failed to create sysfs attributes\n");
                 goto err_cleanup_hid_ll;
         }
 
+        error = device_create_file(&hdev->dev, &dev_attr_operation_mode);
+        if (error) {
+                dev_err(&hdev->dev, "failed to create sysfs attributes\n");
+                goto err_cleanup_sysfs1;
+        }
+
         if (data->status & PICOLCD_BOOTLOADER)
                 error = picolcd_probe_bootloader(hdev, data);
         else
                 error = picolcd_probe_lcd(hdev, data);
         if (error)
-                goto err_cleanup_sysfs;
+                goto err_cleanup_sysfs2;
 
         dbg_hid(PICOLCD_NAME " activated and initialized\n");
         return 0;
 
-err_cleanup_sysfs:
+err_cleanup_sysfs2:
         device_remove_file(&hdev->dev, &dev_attr_operation_mode);
+err_cleanup_sysfs1:
+        device_remove_file(&hdev->dev, &dev_attr_operation_mode_delay);
 err_cleanup_hid_ll:
         hdev->ll_driver->close(hdev);
 err_cleanup_hid_hw:
@@ -2478,6 +2505,7 @@ static void picolcd_remove(struct hid_device *hdev)
 
         picolcd_exit_devfs(data);
         device_remove_file(&hdev->dev, &dev_attr_operation_mode);
+        device_remove_file(&hdev->dev, &dev_attr_operation_mode_delay);
         hdev->ll_driver->close(hdev);
         hid_hw_stop(hdev);
         hid_set_drvdata(hdev, NULL);