Input: wacom - add Intuos4 LED and OLED control

This commit enables control of the LEDs and OLED displays found on the
Wacom Intuos4 M, L, and XL. For this purpose, a new "wacom_led" attribute
group is added to the sysfs entry of the USB device.

This "wacom_led" group only shows up when the correct device (M, L, or XL)
is detected. The attributes are described in
 Documentation/ABI/testing/sysfs-wacom

Signed-off-by: Eduard Hasenleithner <eduard@hasenleithner.at>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

2 files changed, 277 insertions, 30 deletions

diff --git a/drivers/input/tablet/wacom.h b/drivers/input/tablet/wacom.h
index 23317bd09c82..00332d66bc4b 100644
--- a/drivers/input/tablet/wacom.h
+++ b/drivers/input/tablet/wacom.h
@@ -114,6 +114,12 @@ struct wacom {
         struct mutex lock;
         bool open;
         char phys[32];
+        struct wacom_led {
+                u8 select; /* status led selector (0..3, -1=none) */
+                u8 llv;    /* status led brightness no button */
+                u8 hlv;    /* status led brightness button pressed */
+                u8 img_lum;   /* OLED matrix display brightness */
+        } led;
 };
 
 extern const struct usb_device_id wacom_ids[];
diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c
index d27c9d91630b..0eccf57df5cd 100644
--- a/drivers/input/tablet/wacom_sys.c
+++ b/drivers/input/tablet/wacom_sys.c
@@ -48,27 +48,49 @@ struct hid_descriptor {
 /* defines to get/set USB message */
 #define USB_REQ_GET_REPORT      0x01
 #define USB_REQ_SET_REPORT      0x09
+
 #define WAC_HID_FEATURE_REPORT  0x03
 #define WAC_MSG_RETRIES         5
 
-static int usb_get_report(struct usb_interface *intf, unsigned char type,
-                                unsigned char id, void *buf, int size)
+#define WAC_CMD_LED_CONTROL     0x20
+#define WAC_CMD_ICON_START      0x21
+#define WAC_CMD_ICON_XFER       0x23
+#define WAC_CMD_RETRIES         10
+
+static int wacom_get_report(struct usb_interface *intf, u8 type, u8 id,
+                            void *buf, size_t size, unsigned int retries)
 {
-        return usb_control_msg(interface_to_usbdev(intf),
-                usb_rcvctrlpipe(interface_to_usbdev(intf), 0),
-                USB_REQ_GET_REPORT, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-                (type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
-                buf, size, 100);
+        struct usb_device *dev = interface_to_usbdev(intf);
+        int retval;
+
+        do {
+                retval = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
+                                USB_REQ_GET_REPORT,
+                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+                                (type << 8) + id,
+                                intf->altsetting[0].desc.bInterfaceNumber,
+                                buf, size, 100);
+        } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries);
+
+        return retval;
 }
 
-static int usb_set_report(struct usb_interface *intf, unsigned char type,
-                                unsigned char id, void *buf, int size)
+static int wacom_set_report(struct usb_interface *intf, u8 type, u8 id,
+                            void *buf, size_t size, unsigned int retries)
 {
-        return usb_control_msg(interface_to_usbdev(intf),
-                usb_sndctrlpipe(interface_to_usbdev(intf), 0),
-                USB_REQ_SET_REPORT, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-                (type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
-                buf, size, 1000);
+        struct usb_device *dev = interface_to_usbdev(intf);
+        int retval;
+
+        do {
+                retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
+                                USB_REQ_SET_REPORT,
+                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+                                (type << 8) + id,
+                                intf->altsetting[0].desc.bInterfaceNumber,
+                                buf, size, 1000);
+        } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries);
+
+        return retval;
 }
 
 static void wacom_sys_irq(struct urb *urb)
@@ -333,23 +355,23 @@ static int wacom_query_tablet_data(struct usb_interface *intf, struct wacom_feat
                         rep_data[2] = 0;
                         rep_data[3] = 0;
                         report_id = 3;
-                        error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
-                                report_id, rep_data, 4);
+                        error = wacom_set_report(intf, WAC_HID_FEATURE_REPORT,
+                                                 report_id, rep_data, 4, 1);
                         if (error >= 0)
-                                error = usb_get_report(intf,
-                                        WAC_HID_FEATURE_REPORT, report_id,
-                                        rep_data, 4);
+                                error = wacom_get_report(intf,
+                                                WAC_HID_FEATURE_REPORT,
+                                                report_id, rep_data, 4, 1);
                 } while ((error < 0 || rep_data[1] != 4) && limit++ < WAC_MSG_RETRIES);
         } else if (features->type != TABLETPC) {
                 do {
                         rep_data[0] = 2;
                         rep_data[1] = 2;
-                        error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
-                                report_id, rep_data, 2);
+                        error = wacom_set_report(intf, WAC_HID_FEATURE_REPORT,
+                                                 report_id, rep_data, 2, 1);
                         if (error >= 0)
-                                error = usb_get_report(intf,
-                                        WAC_HID_FEATURE_REPORT, report_id,
-                                        rep_data, 2);
+                                error = wacom_get_report(intf,
+                                                WAC_HID_FEATURE_REPORT,
+                                                report_id, rep_data, 2, 1);
                 } while ((error < 0 || rep_data[1] != 2) && limit++ < WAC_MSG_RETRIES);
         }
 
@@ -468,6 +490,220 @@ static void wacom_remove_shared_data(struct wacom_wac *wacom)
         }
 }
 
+static int wacom_led_control(struct wacom *wacom)
+{
+        unsigned char *buf;
+        int retval;
+
+        buf = kzalloc(9, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
+        buf[0] = WAC_CMD_LED_CONTROL;
+        buf[1] = wacom->led.select >= 0 ? wacom->led.select | 4 : 0;
+        buf[2] = wacom->led.llv;
+        buf[3] = wacom->led.hlv;
+        buf[4] = wacom->led.img_lum;
+
+        retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_LED_CONTROL,
+                                  buf, 9, WAC_CMD_RETRIES);
+        kfree(buf);
+
+        return retval;
+}
+
+static int wacom_led_putimage(struct wacom *wacom, int button_id, const void *img)
+{
+        unsigned char *buf;
+        int i, retval;
+
+        buf = kzalloc(259, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
+        /* Send 'start' command */
+        buf[0] = WAC_CMD_ICON_START;
+        buf[1] = 1;
+        retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_START,
+                                  buf, 2, WAC_CMD_RETRIES);
+        if (retval < 0)
+                goto out;
+
+        buf[0] = WAC_CMD_ICON_XFER;
+        buf[1] = button_id & 0x07;
+        for (i = 0; i < 4; i++) {
+                buf[2] = i;
+                memcpy(buf + 3, img + i * 256, 256);
+
+                retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_XFER,
+                                          buf, 259, WAC_CMD_RETRIES);
+                if (retval < 0)
+                        break;
+        }
+
+        /* Send 'stop' */
+        buf[0] = WAC_CMD_ICON_START;
+        buf[1] = 0;
+        wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_START,
+                         buf, 2, WAC_CMD_RETRIES);
+
+out:
+        kfree(buf);
+        return retval;
+}
+
+static ssize_t wacom_led_select_store(struct device *dev,
+                                      struct device_attribute *attr,
+                                      const char *buf, size_t count)
+{
+        struct wacom *wacom = dev_get_drvdata(dev);
+        unsigned int id;
+        int err;
+
+        err = kstrtouint(buf, 10, &id);
+        if (err)
+                return err;
+
+        mutex_lock(&wacom->lock);
+
+        wacom->led.select = id;
+        err = wacom_led_control(wacom);
+
+        mutex_unlock(&wacom->lock);
+
+        return err < 0 ? err : count;
+}
+
+static DEVICE_ATTR(status_led_select, S_IWUSR, NULL, wacom_led_select_store);
+
+static ssize_t wacom_luminance_store(struct wacom *wacom, u8 *dest,
+                                     const char *buf, size_t count)
+{
+        unsigned int value;
+        int err;
+
+        err = kstrtouint(buf, 10, &value);
+        if (err)
+                return err;
+
+        mutex_lock(&wacom->lock);
+
+        *dest = value & 0x7f;
+        err = wacom_led_control(wacom);
+
+        mutex_unlock(&wacom->lock);
+
+        return err < 0 ? err : count;
+}
+
+#define DEVICE_LUMINANCE_ATTR(name, field)                              \
+static ssize_t wacom_##name##_luminance_store(struct device *dev,       \
+        struct device_attribute *attr, const char *buf, size_t count)   \
+{                                                                       \
+        struct wacom *wacom = dev_get_drvdata(dev);                     \
+                                                                        \
+        return wacom_luminance_store(wacom, &wacom->led.field,          \
+                                     buf, count);                       \
+}                                                                       \
+static DEVICE_ATTR(name##_luminance, S_IWUSR,                           \
+                   NULL, wacom_##name##_luminance_store)
+
+DEVICE_LUMINANCE_ATTR(status0, llv);
+DEVICE_LUMINANCE_ATTR(status1, hlv);
+DEVICE_LUMINANCE_ATTR(buttons, img_lum);
+
+static ssize_t wacom_button_image_store(struct device *dev, int button_id,
+                                        const char *buf, size_t count)
+{
+        struct wacom *wacom = dev_get_drvdata(dev);
+        int err;
+
+        if (count != 1024)
+                return -EINVAL;
+
+        mutex_lock(&wacom->lock);
+
+        err = wacom_led_putimage(wacom, button_id, buf);
+
+        mutex_unlock(&wacom->lock);
+
+        return err < 0 ? err : count;
+}
+
+#define DEVICE_BTNIMG_ATTR(BUTTON_ID)                                   \
+static ssize_t wacom_btnimg##BUTTON_ID##_store(struct device *dev,      \
+        struct device_attribute *attr, const char *buf, size_t count)   \
+{                                                                       \
+        return wacom_button_image_store(dev, BUTTON_ID, buf, count);    \
+}                                                                       \
+static DEVICE_ATTR(button##BUTTON_ID##_rawimg, S_IWUSR,                 \
+                   NULL, wacom_btnimg##BUTTON_ID##_store)
+
+DEVICE_BTNIMG_ATTR(0);
+DEVICE_BTNIMG_ATTR(1);
+DEVICE_BTNIMG_ATTR(2);
+DEVICE_BTNIMG_ATTR(3);
+DEVICE_BTNIMG_ATTR(4);
+DEVICE_BTNIMG_ATTR(5);
+DEVICE_BTNIMG_ATTR(6);
+DEVICE_BTNIMG_ATTR(7);
+
+static struct attribute *wacom_led_attrs[] = {
+        &dev_attr_status0_luminance.attr,
+        &dev_attr_status1_luminance.attr,
+        &dev_attr_status_led_select.attr,
+        &dev_attr_buttons_luminance.attr,
+        &dev_attr_button0_rawimg.attr,
+        &dev_attr_button1_rawimg.attr,
+        &dev_attr_button2_rawimg.attr,
+        &dev_attr_button3_rawimg.attr,
+        &dev_attr_button4_rawimg.attr,
+        &dev_attr_button5_rawimg.attr,
+        &dev_attr_button6_rawimg.attr,
+        &dev_attr_button7_rawimg.attr,
+        NULL
+};
+
+static struct attribute_group wacom_led_attr_group = {
+        .name = "wacom_led",
+        .attrs = wacom_led_attrs,
+};
+
+static int wacom_initialize_leds(struct wacom *wacom)
+{
+        int error;
+
+        if (wacom->wacom_wac.features.type >= INTUOS4 &&
+            wacom->wacom_wac.features.type <= INTUOS4L) {
+
+                /* Initialize default values */
+                wacom->led.select = 0;
+                wacom->led.llv = 30;
+                wacom->led.hlv = 20;
+                wacom->led.img_lum = 10;
+                wacom_led_control(wacom);
+
+                error = sysfs_create_group(&wacom->intf->dev.kobj,
+                                           &wacom_led_attr_group);
+                if (error) {
+                        dev_err(&wacom->intf->dev,
+                                "cannot create sysfs group err: %d\n", error);
+                        return error;
+                }
+        }
+
+        return 0;
+}
+
+static void wacom_destroy_leds(struct wacom *wacom)
+{
+        if (wacom->wacom_wac.features.type >= INTUOS4 &&
+            wacom->wacom_wac.features.type <= INTUOS4L) {
+                sysfs_remove_group(&wacom->intf->dev.kobj,
+                                   &wacom_led_attr_group);
+        }
+}
+
 static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
         struct usb_device *dev = interface_to_usbdev(intf);
@@ -556,16 +792,21 @@ static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *i
         wacom->irq->transfer_dma = wacom->data_dma;
         wacom->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 
-        error = input_register_device(input_dev);
+        error = wacom_initialize_leds(wacom);
         if (error)
                 goto fail4;
 
+        error = input_register_device(input_dev);
+        if (error)
+                goto fail5;
+
         /* Note that if query fails it is not a hard failure */
         wacom_query_tablet_data(intf, features);
 
         usb_set_intfdata(intf, wacom);
         return 0;
 
+ fail5: wacom_destroy_leds(wacom);
  fail4: wacom_remove_shared_data(wacom_wac);
  fail3: usb_free_urb(wacom->irq);
  fail2: usb_free_coherent(dev, WACOM_PKGLEN_MAX, wacom_wac->data, wacom->data_dma);
@@ -582,6 +823,7 @@ static void wacom_disconnect(struct usb_interface *intf)
 
         usb_kill_urb(wacom->irq);
         input_unregister_device(wacom->wacom_wac.input);
+        wacom_destroy_leds(wacom);
         usb_free_urb(wacom->irq);
         usb_free_coherent(interface_to_usbdev(intf), WACOM_PKGLEN_MAX,
                         wacom->wacom_wac.data, wacom->data_dma);
@@ -604,17 +846,16 @@ static int wacom_resume(struct usb_interface *intf)
 {
         struct wacom *wacom = usb_get_intfdata(intf);
         struct wacom_features *features = &wacom->wacom_wac.features;
-        int rv;
+        int rv = 0;
 
         mutex_lock(&wacom->lock);
 
         /* switch to wacom mode first */
         wacom_query_tablet_data(intf, features);
+        wacom_led_control(wacom);
 
-        if (wacom->open)
-                rv = usb_submit_urb(wacom->irq, GFP_NOIO);
-        else
-                rv = 0;
+        if (wacom->open && usb_submit_urb(wacom->irq, GFP_NOIO) < 0)
+                rv = -EIO;
 
         mutex_unlock(&wacom->lock);