HID: picoLCD: split driver code

In order to make code maintenance easier, split the vairous
functions into individial files (this removes a bunch of #ifdefs).
Signed-off-by: NBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/hid/Kconfig

@@ -527,6 +527,14 @@ config HID_PICOLCD_LEDS
 	---help---
 	  Provide access to PicoLCD's GPO pins via leds class.
 
+config HID_PICOLCD_CIR
+	bool "CIR via RC class" if EXPERT
+	default !EXPERT
+	depends on HID_PICOLCD
+	depends on HID_PICOLCD=RC_CORE || RC_CORE=y
+	---help---
+	  Provide access to PicoLCD's CIR interface via remote control (LIRC).
+
 config HID_PRIMAX
 	tristate "Primax non-fully HID-compliant devices"
 	depends on USB_HID

drivers/hid/Makefile

@@ -69,6 +69,26 @@ obj-$(CONFIG_HID_PRODIKEYS)	+= hid-prodikeys.o
 obj-$(CONFIG_HID_PANTHERLORD)	+= hid-pl.o
 obj-$(CONFIG_HID_PETALYNX)	+= hid-petalynx.o
 obj-$(CONFIG_HID_PICOLCD)	+= hid-picolcd.o
+hid-picolcd-y			+= hid-picolcd_core.o
+ifdef CONFIG_HID_PICOLCD_FB
+hid-picolcd-y			+= hid-picolcd_fb.o
+endif
+ifdef CONFIG_HID_PICOLCD_BACKLIGHT
+hid-picolcd-y			+= hid-picolcd_backlight.o
+endif
+ifdef CONFIG_HID_PICOLCD_LCD
+hid-picolcd-y			+= hid-picolcd_lcd.o
+endif
+ifdef CONFIG_HID_PICOLCD_LEDS
+hid-picolcd-y			+= hid-picolcd_leds.o
+endif
+ifdef CONFIG_HID_PICOLCD_CIR
+hid-picolcd-y			+= hid-picolcd_cir.o
+endif
+ifdef CONFIG_DEBUG_FS
+hid-picolcd-y			+= hid-picolcd_debugfs.o
+endif
+
 obj-$(CONFIG_HID_PRIMAX)	+= hid-primax.o
 obj-$(CONFIG_HID_ROCCAT)	+= hid-roccat.o hid-roccat-common.o \
 	hid-roccat-arvo.o hid-roccat-isku.o hid-roccat-kone.o \

drivers/hid/hid-picolcd.h

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#define PICOLCD_NAME "PicoLCD (graphic)"
+
+/* Report numbers */
+#define REPORT_ERROR_CODE      0x10 /* LCD: IN[16]  */
+#define   ERR_SUCCESS            0x00
+#define   ERR_PARAMETER_MISSING  0x01
+#define   ERR_DATA_MISSING       0x02
+#define   ERR_BLOCK_READ_ONLY    0x03
+#define   ERR_BLOCK_NOT_ERASABLE 0x04
+#define   ERR_BLOCK_TOO_BIG      0x05
+#define   ERR_SECTION_OVERFLOW   0x06
+#define   ERR_INVALID_CMD_LEN    0x07
+#define   ERR_INVALID_DATA_LEN   0x08
+#define REPORT_KEY_STATE       0x11 /* LCD: IN[2]   */
+#define REPORT_IR_DATA         0x21 /* LCD: IN[63]  */
+#define REPORT_EE_DATA         0x32 /* LCD: IN[63]  */
+#define REPORT_MEMORY          0x41 /* LCD: IN[63]  */
+#define REPORT_LED_STATE       0x81 /* LCD: OUT[1]  */
+#define REPORT_BRIGHTNESS      0x91 /* LCD: OUT[1]  */
+#define REPORT_CONTRAST        0x92 /* LCD: OUT[1]  */
+#define REPORT_RESET           0x93 /* LCD: OUT[2]  */
+#define REPORT_LCD_CMD         0x94 /* LCD: OUT[63] */
+#define REPORT_LCD_DATA        0x95 /* LCD: OUT[63] */
+#define REPORT_LCD_CMD_DATA    0x96 /* LCD: OUT[63] */
+#define	REPORT_EE_READ         0xa3 /* LCD: OUT[63] */
+#define REPORT_EE_WRITE        0xa4 /* LCD: OUT[63] */
+#define REPORT_ERASE_MEMORY    0xb2 /* LCD: OUT[2]  */
+#define REPORT_READ_MEMORY     0xb3 /* LCD: OUT[3]  */
+#define REPORT_WRITE_MEMORY    0xb4 /* LCD: OUT[63] */
+#define REPORT_SPLASH_RESTART  0xc1 /* LCD: OUT[1]  */
+#define REPORT_EXIT_KEYBOARD   0xef /* LCD: OUT[2]  */
+#define REPORT_VERSION         0xf1 /* LCD: IN[2],OUT[1]    Bootloader: IN[2],OUT[1]   */
+#define REPORT_BL_ERASE_MEMORY 0xf2 /*                      Bootloader: IN[36],OUT[4]  */
+#define REPORT_BL_READ_MEMORY  0xf3 /*                      Bootloader: IN[36],OUT[4]  */
+#define REPORT_BL_WRITE_MEMORY 0xf4 /*                      Bootloader: IN[36],OUT[36] */
+#define REPORT_DEVID           0xf5 /* LCD: IN[5], OUT[1]   Bootloader: IN[5],OUT[1]   */
+#define REPORT_SPLASH_SIZE     0xf6 /* LCD: IN[4], OUT[1]   */
+#define REPORT_HOOK_VERSION    0xf7 /* LCD: IN[2], OUT[1]   */
+#define REPORT_EXIT_FLASHER    0xff /*                      Bootloader: OUT[2]         */
+
+/* Description of in-progress IO operation, used for operations
+ * that trigger response from device */
+struct picolcd_pending {
+	struct hid_report *out_report;
+	struct hid_report *in_report;
+	struct completion ready;
+	int raw_size;
+	u8 raw_data[64];
+};
+
+
+#define PICOLCD_KEYS 17
+
+/* Per device data structure */
+struct picolcd_data {
+	struct hid_device *hdev;
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *debug_reset;
+	struct dentry *debug_eeprom;
+	struct dentry *debug_flash;
+	struct mutex mutex_flash;
+	int addr_sz;
+#endif
+	u8 version[2];
+	unsigned short opmode_delay;
+	/* input stuff */
+	u8 pressed_keys[2];
+	struct input_dev *input_keys;
+	struct input_dev *input_cir;
+	unsigned short keycode[PICOLCD_KEYS];
+
+#ifdef CONFIG_HID_PICOLCD_FB
+	/* Framebuffer stuff */
+	u8 fb_update_rate;
+	u8 fb_bpp;
+	u8 fb_force;
+	u8 *fb_vbitmap;		/* local copy of what was sent to PicoLCD */
+	u8 *fb_bitmap;		/* framebuffer */
+	struct fb_info *fb_info;
+	struct fb_deferred_io fb_defio;
+#endif /* CONFIG_HID_PICOLCD_FB */
+#ifdef CONFIG_HID_PICOLCD_LCD
+	struct lcd_device *lcd;
+	u8 lcd_contrast;
+#endif /* CONFIG_HID_PICOLCD_LCD */
+#ifdef CONFIG_HID_PICOLCD_BACKLIGHT
+	struct backlight_device *backlight;
+	u8 lcd_brightness;
+	u8 lcd_power;
+#endif /* CONFIG_HID_PICOLCD_BACKLIGHT */
+#ifdef CONFIG_HID_PICOLCD_LEDS
+	/* LED stuff */
+	u8 led_state;
+	struct led_classdev *led[8];
+#endif /* CONFIG_HID_PICOLCD_LEDS */
+
+	/* Housekeeping stuff */
+	spinlock_t lock;
+	struct mutex mutex;
+	struct picolcd_pending *pending;
+	int status;
+#define PICOLCD_BOOTLOADER 1
+#define PICOLCD_FAILED 2
+#define PICOLCD_READY_FB 4
+};
+
+
+/* Find a given report */
+#define picolcd_in_report(id, dev) picolcd_report(id, dev, HID_INPUT_REPORT)
+#define picolcd_out_report(id, dev) picolcd_report(id, dev, HID_OUTPUT_REPORT)
+
+struct hid_report *picolcd_report(int id, struct hid_device *hdev, int dir);
+
+#ifdef CONFIG_DEBUG_FS
+void picolcd_debug_out_report(struct picolcd_data *data,
+		struct hid_device *hdev, struct hid_report *report);
+#define usbhid_submit_report(a, b, c) \
+	do { \
+		picolcd_debug_out_report(hid_get_drvdata(a), a, b); \
+		usbhid_submit_report(a, b, c); \
+	} while (0)
+
+void picolcd_debug_raw_event(struct picolcd_data *data,
+		struct hid_device *hdev, struct hid_report *report,
+		u8 *raw_data, int size);
+
+void picolcd_init_devfs(struct picolcd_data *data,
+		struct hid_report *eeprom_r, struct hid_report *eeprom_w,
+		struct hid_report *flash_r, struct hid_report *flash_w,
+		struct hid_report *reset);
+
+void picolcd_exit_devfs(struct picolcd_data *data);
+#else
+static inline void picolcd_debug_raw_event(struct picolcd_data *data,
+		struct hid_device *hdev, struct hid_report *report,
+		u8 *raw_data, int size)
+{
+}
+static inline void picolcd_init_devfs(struct picolcd_data *data,
+		struct hid_report *eeprom_r, struct hid_report *eeprom_w,
+		struct hid_report *flash_r, struct hid_report *flash_w,
+		struct hid_report *reset)
+{
+}
+static inline void picolcd_exit_devfs(struct picolcd_data *data)
+{
+}
+static inline void picolcd_debug_raw_event(struct picolcd_data *data,
+		struct hid_device *hdev, struct hid_report *report,
+		u8 *raw_data, int size)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+
+#ifdef CONFIG_HID_PICOLCD_FB
+int picolcd_fb_reset(struct picolcd_data *data, int clear);
+
+int picolcd_init_framebuffer(struct picolcd_data *data);
+
+void picolcd_exit_framebuffer(struct picolcd_data *data);
+
+void picolcd_fb_unload(void);
+
+void picolcd_fb_refresh(struct picolcd_data *data);
+#define picolcd_fbinfo(d) ((d)->fb_info)
+#else
+static inline int picolcd_fb_reset(struct picolcd_data *data, int clear)
+{
+	return 0;
+}
+static inline int picolcd_init_framebuffer(struct picolcd_data *data)
+{
+	return 0;
+}
+static inline void picolcd_exit_framebuffer(struct picolcd_data *data)
+{
+}
+static inline void picolcd_fb_unload(void)
+{
+}
+static inline void picolcd_fb_refresh(struct picolcd_data *data)
+{
+}
+#define picolcd_fbinfo(d) NULL
+#endif /* CONFIG_HID_PICOLCD_FB */
+
+
+#ifdef CONFIG_HID_PICOLCD_BACKLIGHT
+int picolcd_init_backlight(struct picolcd_data *data,
+		struct hid_report *report);
+
+void picolcd_exit_backlight(struct picolcd_data *data);
+
+int picolcd_resume_backlight(struct picolcd_data *data);
+
+void picolcd_suspend_backlight(struct picolcd_data *data);
+#else
+static inline int picolcd_init_backlight(struct picolcd_data *data,
+		struct hid_report *report)
+{
+	return 0;
+}
+static inline void picolcd_exit_backlight(struct picolcd_data *data)
+{
+}
+static inline int picolcd_resume_backlight(struct picolcd_data *data)
+{
+	return 0;
+}
+static inline void picolcd_suspend_backlight(struct picolcd_data *data)
+{
+}
+
+#endif /* CONFIG_HID_PICOLCD_BACKLIGHT */
+
+
+#ifdef CONFIG_HID_PICOLCD_LCD
+int picolcd_init_lcd(struct picolcd_data *data,
+		struct hid_report *report);
+
+void picolcd_exit_lcd(struct picolcd_data *data);
+
+int picolcd_resume_lcd(struct picolcd_data *data);
+#else
+static inline int picolcd_init_lcd(struct picolcd_data *data,
+		struct hid_report *report)
+{
+	return 0;
+}
+static inline void picolcd_exit_lcd(struct picolcd_data *data)
+{
+}
+static inline int picolcd_resume_lcd(struct picolcd_data *data)
+{
+	return 0;
+}
+#endif /* CONFIG_HID_PICOLCD_LCD */
+
+
+#ifdef CONFIG_HID_PICOLCD_LEDS
+int picolcd_init_leds(struct picolcd_data *data,
+		struct hid_report *report);
+
+void picolcd_exit_leds(struct picolcd_data *data);
+
+void picolcd_leds_set(struct picolcd_data *data);
+#else
+static inline int picolcd_init_leds(struct picolcd_data *data,
+		struct hid_report *report)
+{
+	return 0;
+}
+static inline void picolcd_exit_leds(struct picolcd_data *data)
+{
+}
+static inline void picolcd_leds_set(struct picolcd_data *data)
+{
+}
+#endif /* CONFIG_HID_PICOLCD_LEDS */
+
+
+#ifdef CONFIG_HID_PICOLCD_CIR
+int picolcd_raw_cir(struct picolcd_data *data,
+		struct hid_report *report, u8 *raw_data, int size);
+
+int picolcd_init_cir(struct picolcd_data *data, struct hid_report *report);
+
+void picolcd_exit_cir(struct picolcd_data *data);
+#else
+static inline int picolcd_raw_cir(struct picolcd_data *data,
+		struct hid_report *report, u8 *raw_data, int size)
+{
+	return 1;
+}
+static inline int picolcd_init_cir(struct picolcd_data *data, struct hid_report *report)
+{
+	return 0;
+}
+static inline void picolcd_exit_cir(struct picolcd_data *data)
+{
+}
+#endif /* CONFIG_HID_PICOLCD_LIRC */
+
+int picolcd_reset(struct hid_device *hdev);
+struct picolcd_pending *picolcd_send_and_wait(struct hid_device *hdev,
+			int report_id, const u8 *raw_data, int size);

drivers/hid/hid-picolcd_backlight.c

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include "usbhid/usbhid.h"
+#include <linux/usb.h>
+
+#include <linux/fb.h>
+#include <linux/backlight.h>
+
+#include "hid-picolcd.h"
+
+static int picolcd_get_brightness(struct backlight_device *bdev)
+{
+	struct picolcd_data *data = bl_get_data(bdev);
+	return data->lcd_brightness;
+}
+
+static int picolcd_set_brightness(struct backlight_device *bdev)
+{
+	struct picolcd_data *data = bl_get_data(bdev);
+	struct hid_report *report = picolcd_out_report(REPORT_BRIGHTNESS, data->hdev);
+	unsigned long flags;
+
+	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
+		return -ENODEV;
+
+	data->lcd_brightness = bdev->props.brightness & 0x0ff;
+	data->lcd_power      = bdev->props.power;
+	spin_lock_irqsave(&data->lock, flags);
+	hid_set_field(report->field[0], 0, data->lcd_power == FB_BLANK_UNBLANK ? data->lcd_brightness : 0);
+	usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
+	spin_unlock_irqrestore(&data->lock, flags);
+	return 0;
+}
+
+static int picolcd_check_bl_fb(struct backlight_device *bdev, struct fb_info *fb)
+{
+	return fb && fb == picolcd_fbinfo((struct picolcd_data *)bl_get_data(bdev));
+}
+
+static const struct backlight_ops picolcd_blops = {
+	.update_status  = picolcd_set_brightness,
+	.get_brightness = picolcd_get_brightness,
+	.check_fb       = picolcd_check_bl_fb,
+};
+
+int picolcd_init_backlight(struct picolcd_data *data, struct hid_report *report)
+{
+	struct device *dev = &data->hdev->dev;
+	struct backlight_device *bdev;
+	struct backlight_properties props;
+	if (!report)
+		return -ENODEV;
+	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
+			report->field[0]->report_size != 8) {
+		dev_err(dev, "unsupported BRIGHTNESS report");
+		return -EINVAL;
+	}
+
+	memset(&props, 0, sizeof(props));
+	props.type = BACKLIGHT_RAW;
+	props.max_brightness = 0xff;
+	bdev = backlight_device_register(dev_name(dev), dev, data,
+			&picolcd_blops, &props);
+	if (IS_ERR(bdev)) {
+		dev_err(dev, "failed to register backlight\n");
+		return PTR_ERR(bdev);
+	}
+	bdev->props.brightness     = 0xff;
+	data->lcd_brightness       = 0xff;
+	data->backlight            = bdev;
+	picolcd_set_brightness(bdev);
+	return 0;
+}
+
+void picolcd_exit_backlight(struct picolcd_data *data)
+{
+	struct backlight_device *bdev = data->backlight;
+
+	data->backlight = NULL;
+	if (bdev)
+		backlight_device_unregister(bdev);
+}
+
+int picolcd_resume_backlight(struct picolcd_data *data)
+{
+	if (!data->backlight)
+		return 0;
+	return picolcd_set_brightness(data->backlight);
+}
+
+#ifdef CONFIG_PM
+void picolcd_suspend_backlight(struct picolcd_data *data)
+{
+	int bl_power = data->lcd_power;
+	if (!data->backlight)
+		return;
+
+	data->backlight->props.power = FB_BLANK_POWERDOWN;
+	picolcd_set_brightness(data->backlight);
+	data->lcd_power = data->backlight->props.power = bl_power;
+}
+#endif /* CONFIG_PM */
+

drivers/hid/hid-picolcd_cir.c

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include <linux/hid-debug.h>
+#include <linux/input.h>
+#include "hid-ids.h"
+#include "usbhid/usbhid.h"
+#include <linux/usb.h>
+
+#include <linux/fb.h>
+#include <linux/vmalloc.h>
+#include <linux/backlight.h>
+#include <linux/lcd.h>
+
+#include <linux/leds.h>
+
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+
+#include <linux/completion.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+
+#include "hid-picolcd.h"
+
+
+int picolcd_raw_cir(struct picolcd_data *data,
+		struct hid_report *report, u8 *raw_data, int size)
+{
+	/* Need understanding of CIR data format to implement ... */
+	return 1;
+}
+
+/* initialize CIR input device */
+int picolcd_init_cir(struct picolcd_data *data, struct hid_report *report)
+{
+	/* support not implemented yet */
+	return 0;
+}
+
+void picolcd_exit_cir(struct picolcd_data *data)
+{
+}
+

drivers/hid/hid-picolcd_fb.c

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include "usbhid/usbhid.h"
+#include <linux/usb.h>
+
+#include <linux/fb.h>
+#include <linux/module.h>
+
+#include "hid-picolcd.h"
+
+/* Framebuffer
+ *
+ * The PicoLCD use a Topway LCD module of 256x64 pixel
+ * This display area is tiled over 4 controllers with 8 tiles
+ * each. Each tile has 8x64 pixel, each data byte representing
+ * a 1-bit wide vertical line of the tile.
+ *
+ * The display can be updated at a tile granularity.
+ *
+ *       Chip 1           Chip 2           Chip 3           Chip 4
+ * +----------------+----------------+----------------+----------------+
+ * |     Tile 1     |     Tile 1     |     Tile 1     |     Tile 1     |
+ * +----------------+----------------+----------------+----------------+
+ * |     Tile 2     |     Tile 2     |     Tile 2     |     Tile 2     |
+ * +----------------+----------------+----------------+----------------+
+ *                                  ...
+ * +----------------+----------------+----------------+----------------+
+ * |     Tile 8     |     Tile 8     |     Tile 8     |     Tile 8     |
+ * +----------------+----------------+----------------+----------------+
+ */
+#define PICOLCDFB_NAME "picolcdfb"
+#define PICOLCDFB_WIDTH (256)
+#define PICOLCDFB_HEIGHT (64)
+#define PICOLCDFB_SIZE (PICOLCDFB_WIDTH * PICOLCDFB_HEIGHT / 8)
+
+#define PICOLCDFB_UPDATE_RATE_LIMIT   10
+#define PICOLCDFB_UPDATE_RATE_DEFAULT  2
+
+/* Framebuffer visual structures */
+static const struct fb_fix_screeninfo picolcdfb_fix = {
+	.id          = PICOLCDFB_NAME,
+	.type        = FB_TYPE_PACKED_PIXELS,
+	.visual      = FB_VISUAL_MONO01,
+	.xpanstep    = 0,
+	.ypanstep    = 0,
+	.ywrapstep   = 0,
+	.line_length = PICOLCDFB_WIDTH / 8,
+	.accel       = FB_ACCEL_NONE,
+};
+
+static const struct fb_var_screeninfo picolcdfb_var = {
+	.xres           = PICOLCDFB_WIDTH,
+	.yres           = PICOLCDFB_HEIGHT,
+	.xres_virtual   = PICOLCDFB_WIDTH,
+	.yres_virtual   = PICOLCDFB_HEIGHT,
+	.width          = 103,
+	.height         = 26,
+	.bits_per_pixel = 1,
+	.grayscale      = 1,
+	.red            = {
+		.offset = 0,
+		.length = 1,
+		.msb_right = 0,
+	},
+	.green          = {
+		.offset = 0,
+		.length = 1,
+		.msb_right = 0,
+	},
+	.blue           = {
+		.offset = 0,
+		.length = 1,
+		.msb_right = 0,
+	},
+	.transp         = {
+		.offset = 0,
+		.length = 0,
+		.msb_right = 0,
+	},
+};
+
+/* Send a given tile to PicoLCD */
+static int picolcd_fb_send_tile(struct hid_device *hdev, int chip, int tile)
+{
+	struct picolcd_data *data = hid_get_drvdata(hdev);
+	struct hid_report *report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, hdev);
+	struct hid_report *report2 = picolcd_out_report(REPORT_LCD_DATA, hdev);
+	unsigned long flags;
+	u8 *tdata;
+	int i;
+
+	if (!report1 || report1->maxfield != 1 || !report2 || report2->maxfield != 1)
+		return -ENODEV;
+
+	spin_lock_irqsave(&data->lock, flags);
+	hid_set_field(report1->field[0],  0, chip << 2);
+	hid_set_field(report1->field[0],  1, 0x02);
+	hid_set_field(report1->field[0],  2, 0x00);
+	hid_set_field(report1->field[0],  3, 0x00);
+	hid_set_field(report1->field[0],  4, 0xb8 | tile);
+	hid_set_field(report1->field[0],  5, 0x00);
+	hid_set_field(report1->field[0],  6, 0x00);
+	hid_set_field(report1->field[0],  7, 0x40);
+	hid_set_field(report1->field[0],  8, 0x00);
+	hid_set_field(report1->field[0],  9, 0x00);
+	hid_set_field(report1->field[0], 10,   32);
+
+	hid_set_field(report2->field[0],  0, (chip << 2) | 0x01);
+	hid_set_field(report2->field[0],  1, 0x00);
+	hid_set_field(report2->field[0],  2, 0x00);
+	hid_set_field(report2->field[0],  3,   32);
+
+	tdata = data->fb_vbitmap + (tile * 4 + chip) * 64;
+	for (i = 0; i < 64; i++)
+		if (i < 32)
+			hid_set_field(report1->field[0], 11 + i, tdata[i]);
+		else
+			hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);
+
+	usbhid_submit_report(data->hdev, report1, USB_DIR_OUT);
+	usbhid_submit_report(data->hdev, report2, USB_DIR_OUT);
+	spin_unlock_irqrestore(&data->lock, flags);
+	return 0;
+}
+
+/* Translate a single tile*/
+static int picolcd_fb_update_tile(u8 *vbitmap, const u8 *bitmap, int bpp,
+		int chip, int tile)
+{
+	int i, b, changed = 0;
+	u8 tdata[64];
+	u8 *vdata = vbitmap + (tile * 4 + chip) * 64;
+
+	if (bpp == 1) {
+		for (b = 7; b >= 0; b--) {
+			const u8 *bdata = bitmap + tile * 256 + chip * 8 + b * 32;
+			for (i = 0; i < 64; i++) {
+				tdata[i] <<= 1;
+				tdata[i] |= (bdata[i/8] >> (i % 8)) & 0x01;
+			}
+		}
+	} else if (bpp == 8) {
+		for (b = 7; b >= 0; b--) {
+			const u8 *bdata = bitmap + (tile * 256 + chip * 8 + b * 32) * 8;
+			for (i = 0; i < 64; i++) {
+				tdata[i] <<= 1;
+				tdata[i] |= (bdata[i] & 0x80) ? 0x01 : 0x00;
+			}
+		}
+	} else {
+		/* Oops, we should never get here! */
+		WARN_ON(1);
+		return 0;
+	}
+
+	for (i = 0; i < 64; i++)
+		if (tdata[i] != vdata[i]) {
+			changed = 1;
+			vdata[i] = tdata[i];
+		}
+	return changed;
+}
+
+void picolcd_fb_refresh(struct picolcd_data *data)
+{
+	if (data->fb_info)
+		schedule_delayed_work(&data->fb_info->deferred_work, 0);
+}
+
+/* Reconfigure LCD display */
+int picolcd_fb_reset(struct picolcd_data *data, int clear)
+{
+	struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
+	int i, j;
+	unsigned long flags;
+	static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };
+
+	if (!report || report->maxfield != 1)
+		return -ENODEV;
+
+	spin_lock_irqsave(&data->lock, flags);
+	for (i = 0; i < 4; i++) {
+		for (j = 0; j < report->field[0]->maxusage; j++)
+			if (j == 0)
+				hid_set_field(report->field[0], j, i << 2);
+			else if (j < sizeof(mapcmd))
+				hid_set_field(report->field[0], j, mapcmd[j]);
+			else
+				hid_set_field(report->field[0], j, 0);
+		usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
+	}
+
+	data->status |= PICOLCD_READY_FB;
+	spin_unlock_irqrestore(&data->lock, flags);
+
+	if (data->fb_bitmap) {
+		if (clear) {
+			memset(data->fb_vbitmap, 0, PICOLCDFB_SIZE);
+			memset(data->fb_bitmap, 0, PICOLCDFB_SIZE*data->fb_bpp);
+		}
+		data->fb_force = 1;
+	}
+
+	/* schedule first output of framebuffer */
+	picolcd_fb_refresh(data);
+
+	return 0;
+}
+
+/* Update fb_vbitmap from the screen_base and send changed tiles to device */
+static void picolcd_fb_update(struct picolcd_data *data)
+{
+	int chip, tile, n;
+	unsigned long flags;
+
+	if (!data)
+		return;
+
+	spin_lock_irqsave(&data->lock, flags);
+	if (!(data->status & PICOLCD_READY_FB)) {
+		spin_unlock_irqrestore(&data->lock, flags);
+		picolcd_fb_reset(data, 0);
+	} else {
+		spin_unlock_irqrestore(&data->lock, flags);
+	}
+
+	/*
+	 * Translate the framebuffer into the format needed by the PicoLCD.
+	 * See display layout above.
+	 * Do this one tile after the other and push those tiles that changed.
+	 *
+	 * Wait for our IO to complete as otherwise we might flood the queue!
+	 */
+	n = 0;
+	for (chip = 0; chip < 4; chip++)
+		for (tile = 0; tile < 8; tile++)
+			if (picolcd_fb_update_tile(data->fb_vbitmap,
+					data->fb_bitmap, data->fb_bpp, chip, tile) ||
+				data->fb_force) {
+				n += 2;
+				if (!data->fb_info->par)
+					return; /* device lost! */
+				if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
+					usbhid_wait_io(data->hdev);
+					n = 0;
+				}
+				picolcd_fb_send_tile(data->hdev, chip, tile);
+			}
+	data->fb_force = false;
+	if (n)
+		usbhid_wait_io(data->hdev);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_fillrect(struct fb_info *info,
+		const struct fb_fillrect *rect)
+{
+	if (!info->par)
+		return;
+	sys_fillrect(info, rect);
+
+	schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_copyarea(struct fb_info *info,
+		const struct fb_copyarea *area)
+{
+	if (!info->par)
+		return;
+	sys_copyarea(info, area);
+
+	schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_imageblit(struct fb_info *info, const struct fb_image *image)
+{
+	if (!info->par)
+		return;
+	sys_imageblit(info, image);
+
+	schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/*
+ * this is the slow path from userspace. they can seek and write to
+ * the fb. it's inefficient to do anything less than a full screen draw
+ */
+static ssize_t picolcd_fb_write(struct fb_info *info, const char __user *buf,
+		size_t count, loff_t *ppos)
+{
+	ssize_t ret;
+	if (!info->par)
+		return -ENODEV;
+	ret = fb_sys_write(info, buf, count, ppos);
+	if (ret >= 0)
+		schedule_delayed_work(&info->deferred_work, 0);
+	return ret;
+}
+
+static int picolcd_fb_blank(int blank, struct fb_info *info)
+{
+	if (!info->par)
+		return -ENODEV;
+	/* We let fb notification do this for us via lcd/backlight device */
+	return 0;
+}
+
+static void picolcd_fb_destroy(struct fb_info *info)
+{
+	struct picolcd_data *data = info->par;
+	u32 *ref_cnt = info->pseudo_palette;
+	int may_release;
+
+	info->par = NULL;
+	if (data)
+		data->fb_info = NULL;
+	fb_deferred_io_cleanup(info);
+
+	ref_cnt--;
+	mutex_lock(&info->lock);
+	(*ref_cnt)--;
+	may_release = !*ref_cnt;
+	mutex_unlock(&info->lock);
+	if (may_release) {
+		vfree((u8 *)info->fix.smem_start);
+		framebuffer_release(info);
+	}
+}
+
+static int picolcd_fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+	__u32 bpp      = var->bits_per_pixel;
+	__u32 activate = var->activate;
+
+	/* only allow 1/8 bit depth (8-bit is grayscale) */
+	*var = picolcdfb_var;
+	var->activate = activate;
+	if (bpp >= 8) {
+		var->bits_per_pixel = 8;
+		var->red.length     = 8;
+		var->green.length   = 8;
+		var->blue.length    = 8;
+	} else {
+		var->bits_per_pixel = 1;
+		var->red.length     = 1;
+		var->green.length   = 1;
+		var->blue.length    = 1;
+	}
+	return 0;
+}
+
+static int picolcd_set_par(struct fb_info *info)
+{
+	struct picolcd_data *data = info->par;
+	u8 *tmp_fb, *o_fb;
+	if (!data)
+		return -ENODEV;
+	if (info->var.bits_per_pixel == data->fb_bpp)
+		return 0;
+	/* switch between 1/8 bit depths */
+	if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
+		return -EINVAL;
+
+	o_fb   = data->fb_bitmap;
+	tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
+	if (!tmp_fb)
+		return -ENOMEM;
+
+	/* translate FB content to new bits-per-pixel */
+	if (info->var.bits_per_pixel == 1) {
+		int i, b;
+		for (i = 0; i < PICOLCDFB_SIZE; i++) {
+			u8 p = 0;
+			for (b = 0; b < 8; b++) {
+				p <<= 1;
+				p |= o_fb[i*8+b] ? 0x01 : 0x00;
+			}
+			tmp_fb[i] = p;
+		}
+		memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
+		info->fix.visual = FB_VISUAL_MONO01;
+		info->fix.line_length = PICOLCDFB_WIDTH / 8;
+	} else {
+		int i;
+		memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
+		for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
+			o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
+		info->fix.visual = FB_VISUAL_DIRECTCOLOR;
+		info->fix.line_length = PICOLCDFB_WIDTH;
+	}
+
+	kfree(tmp_fb);
+	data->fb_bpp      = info->var.bits_per_pixel;
+	return 0;
+}
+
+/* Do refcounting on our FB and cleanup per worker if FB is
+ * closed after unplug of our device
+ * (fb_release holds info->lock and still touches info after
+ *  we return so we can't release it immediately.
+ */
+struct picolcd_fb_cleanup_item {
+	struct fb_info *info;
+	struct picolcd_fb_cleanup_item *next;
+};
+static struct picolcd_fb_cleanup_item *fb_pending;
+static DEFINE_SPINLOCK(fb_pending_lock);
+
+static void picolcd_fb_do_cleanup(struct work_struct *data)
+{
+	struct picolcd_fb_cleanup_item *item;
+	unsigned long flags;
+
+	do {
+		spin_lock_irqsave(&fb_pending_lock, flags);
+		item = fb_pending;
+		fb_pending = item ? item->next : NULL;
+		spin_unlock_irqrestore(&fb_pending_lock, flags);
+
+		if (item) {
+			u8 *fb = (u8 *)item->info->fix.smem_start;
+			/* make sure we do not race against fb core when
+			 * releasing */
+			mutex_lock(&item->info->lock);
+			mutex_unlock(&item->info->lock);
+			framebuffer_release(item->info);
+			vfree(fb);
+		}
+	} while (item);
+}
+
+static DECLARE_WORK(picolcd_fb_cleanup, picolcd_fb_do_cleanup);
+
+static int picolcd_fb_open(struct fb_info *info, int u)
+{
+	u32 *ref_cnt = info->pseudo_palette;
+	ref_cnt--;
+
+	(*ref_cnt)++;
+	return 0;
+}
+
+static int picolcd_fb_release(struct fb_info *info, int u)
+{
+	u32 *ref_cnt = info->pseudo_palette;
+	ref_cnt--;
+
+	(*ref_cnt)++;
+	if (!*ref_cnt) {
+		unsigned long flags;
+		struct picolcd_fb_cleanup_item *item = (struct picolcd_fb_cleanup_item *)ref_cnt;
+		item--;
+		spin_lock_irqsave(&fb_pending_lock, flags);
+		item->next = fb_pending;
+		fb_pending = item;
+		spin_unlock_irqrestore(&fb_pending_lock, flags);
+		schedule_work(&picolcd_fb_cleanup);
+	}
+	return 0;
+}
+
+/* Note this can't be const because of struct fb_info definition */
+static struct fb_ops picolcdfb_ops = {
+	.owner        = THIS_MODULE,
+	.fb_destroy   = picolcd_fb_destroy,
+	.fb_open      = picolcd_fb_open,
+	.fb_release   = picolcd_fb_release,
+	.fb_read      = fb_sys_read,
+	.fb_write     = picolcd_fb_write,
+	.fb_blank     = picolcd_fb_blank,
+	.fb_fillrect  = picolcd_fb_fillrect,
+	.fb_copyarea  = picolcd_fb_copyarea,
+	.fb_imageblit = picolcd_fb_imageblit,
+	.fb_check_var = picolcd_fb_check_var,
+	.fb_set_par   = picolcd_set_par,
+};
+
+
+/* Callback from deferred IO workqueue */
+static void picolcd_fb_deferred_io(struct fb_info *info, struct list_head *pagelist)
+{
+	picolcd_fb_update(info->par);
+}
+
+static const struct fb_deferred_io picolcd_fb_defio = {
+	.delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
+	.deferred_io = picolcd_fb_deferred_io,
+};
+
+
+/*
+ * The "fb_update_rate" sysfs attribute
+ */
+static ssize_t picolcd_fb_update_rate_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct picolcd_data *data = dev_get_drvdata(dev);
+	unsigned i, fb_update_rate = data->fb_update_rate;
+	size_t ret = 0;
+
+	for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
+		if (ret >= PAGE_SIZE)
+			break;
+		else if (i == fb_update_rate)
+			ret += snprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
+		else
+			ret += snprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
+	if (ret > 0)
+		buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
+	return ret;
+}
+
+static ssize_t picolcd_fb_update_rate_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct picolcd_data *data = dev_get_drvdata(dev);
+	int i;
+	unsigned u;
+
+	if (count < 1 || count > 10)
+		return -EINVAL;
+
+	i = sscanf(buf, "%u", &u);
+	if (i != 1)
+		return -EINVAL;
+
+	if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
+		return -ERANGE;
+	else if (u == 0)
+		u = PICOLCDFB_UPDATE_RATE_DEFAULT;
+
+	data->fb_update_rate = u;
+	data->fb_defio.delay = HZ / data->fb_update_rate;
+	return count;
+}
+
+static DEVICE_ATTR(fb_update_rate, 0666, picolcd_fb_update_rate_show,
+		picolcd_fb_update_rate_store);
+
+/* initialize Framebuffer device */
+int picolcd_init_framebuffer(struct picolcd_data *data)
+{
+	struct device *dev = &data->hdev->dev;
+	struct fb_info *info = NULL;
+	int i, error = -ENOMEM;
+	u8 *fb_vbitmap = NULL;
+	u8 *fb_bitmap  = NULL;
+	u32 *palette;
+
+	fb_bitmap = vmalloc(PICOLCDFB_SIZE*8);
+	if (fb_bitmap == NULL) {
+		dev_err(dev, "can't get a free page for framebuffer\n");
+		goto err_nomem;
+	}
+
+	fb_vbitmap = kmalloc(PICOLCDFB_SIZE, GFP_KERNEL);
+	if (fb_vbitmap == NULL) {
+		dev_err(dev, "can't alloc vbitmap image buffer\n");
+		goto err_nomem;
+	}
+
+	data->fb_update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
+	data->fb_defio = picolcd_fb_defio;
+	/* The extra memory is:
+	 * - struct picolcd_fb_cleanup_item
+	 * - u32 for ref_count
+	 * - 256*u32 for pseudo_palette
+	 */
+	info = framebuffer_alloc(257 * sizeof(u32) + sizeof(struct picolcd_fb_cleanup_item), dev);
+	if (info == NULL) {
+		dev_err(dev, "failed to allocate a framebuffer\n");
+		goto err_nomem;
+	}
+
+	palette  = info->par + sizeof(struct picolcd_fb_cleanup_item);
+	*palette = 1;
+	palette++;
+	for (i = 0; i < 256; i++)
+		palette[i] = i > 0 && i < 16 ? 0xff : 0;
+	info->pseudo_palette = palette;
+	info->fbdefio = &data->fb_defio;
+	info->screen_base = (char __force __iomem *)fb_bitmap;
+	info->fbops = &picolcdfb_ops;
+	info->var = picolcdfb_var;
+	info->fix = picolcdfb_fix;
+	info->fix.smem_len   = PICOLCDFB_SIZE*8;
+	info->fix.smem_start = (unsigned long)fb_bitmap;
+	info->par = data;
+	info->flags = FBINFO_FLAG_DEFAULT;
+
+	data->fb_vbitmap = fb_vbitmap;
+	data->fb_bitmap  = fb_bitmap;
+	data->fb_bpp     = picolcdfb_var.bits_per_pixel;
+	error = picolcd_fb_reset(data, 1);
+	if (error) {
+		dev_err(dev, "failed to configure display\n");
+		goto err_cleanup;
+	}
+	error = device_create_file(dev, &dev_attr_fb_update_rate);
+	if (error) {
+		dev_err(dev, "failed to create sysfs attributes\n");
+		goto err_cleanup;
+	}
+	fb_deferred_io_init(info);
+	data->fb_info    = info;
+	error = register_framebuffer(info);
+	if (error) {
+		dev_err(dev, "failed to register framebuffer\n");
+		goto err_sysfs;
+	}
+	/* schedule first output of framebuffer */
+	data->fb_force = 1;
+	schedule_delayed_work(&info->deferred_work, 0);
+	return 0;
+
+err_sysfs:
+	fb_deferred_io_cleanup(info);
+	device_remove_file(dev, &dev_attr_fb_update_rate);
+err_cleanup:
+	data->fb_vbitmap = NULL;
+	data->fb_bitmap  = NULL;
+	data->fb_bpp     = 0;
+	data->fb_info    = NULL;
+
+err_nomem:
+	framebuffer_release(info);
+	vfree(fb_bitmap);
+	kfree(fb_vbitmap);
+	return error;
+}
+
+void picolcd_exit_framebuffer(struct picolcd_data *data)
+{
+	struct fb_info *info = data->fb_info;
+	u8 *fb_vbitmap = data->fb_vbitmap;
+
+	if (!info)
+		return;
+
+	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
+	unregister_framebuffer(info);
+	data->fb_vbitmap = NULL;
+	data->fb_bitmap  = NULL;
+	data->fb_bpp     = 0;
+	data->fb_info    = NULL;
+	kfree(fb_vbitmap);
+}
+
+void picolcd_fb_unload()
+{
+	flush_work_sync(&picolcd_fb_cleanup);
+	WARN_ON(fb_pending);
+}

drivers/hid/hid-picolcd_lcd.c

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include "usbhid/usbhid.h"
+#include <linux/usb.h>
+
+#include <linux/fb.h>
+#include <linux/lcd.h>
+
+#include "hid-picolcd.h"
+
+/*
+ * lcd class device
+ */
+static int picolcd_get_contrast(struct lcd_device *ldev)
+{
+	struct picolcd_data *data = lcd_get_data(ldev);
+	return data->lcd_contrast;
+}
+
+static int picolcd_set_contrast(struct lcd_device *ldev, int contrast)
+{
+	struct picolcd_data *data = lcd_get_data(ldev);
+	struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev);
+	unsigned long flags;
+
+	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
+		return -ENODEV;
+
+	data->lcd_contrast = contrast & 0x0ff;
+	spin_lock_irqsave(&data->lock, flags);
+	hid_set_field(report->field[0], 0, data->lcd_contrast);
+	usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
+	spin_unlock_irqrestore(&data->lock, flags);
+	return 0;
+}
+
+static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb)
+{
+	return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev));
+}
+
+static struct lcd_ops picolcd_lcdops = {
+	.get_contrast   = picolcd_get_contrast,
+	.set_contrast   = picolcd_set_contrast,
+	.check_fb       = picolcd_check_lcd_fb,
+};
+
+int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report)
+{
+	struct device *dev = &data->hdev->dev;
+	struct lcd_device *ldev;
+
+	if (!report)
+		return -ENODEV;
+	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
+			report->field[0]->report_size != 8) {
+		dev_err(dev, "unsupported CONTRAST report");
+		return -EINVAL;
+	}
+
+	ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops);
+	if (IS_ERR(ldev)) {
+		dev_err(dev, "failed to register LCD\n");
+		return PTR_ERR(ldev);
+	}
+	ldev->props.max_contrast = 0x0ff;
+	data->lcd_contrast = 0xe5;
+	data->lcd = ldev;
+	picolcd_set_contrast(ldev, 0xe5);
+	return 0;
+}
+
+void picolcd_exit_lcd(struct picolcd_data *data)
+{
+	struct lcd_device *ldev = data->lcd;
+
+	data->lcd = NULL;
+	if (ldev)
+		lcd_device_unregister(ldev);
+}
+
+int picolcd_resume_lcd(struct picolcd_data *data)
+{
+	if (!data->lcd)
+		return 0;
+	return picolcd_set_contrast(data->lcd, data->lcd_contrast);
+}
+

drivers/hid/hid-picolcd_leds.c

+/***************************************************************************
+ *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
+ *                                                                         *
+ *   Based on Logitech G13 driver (v0.4)                                   *
+ *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
+ *                                                                         *
+ *   This program is free software: you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation, version 2 of the License.               *
+ *                                                                         *
+ *   This driver is distributed in the hope that it will be useful, but    *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include <linux/hid-debug.h>
+#include <linux/input.h>
+#include "hid-ids.h"
+#include "usbhid/usbhid.h"
+#include <linux/usb.h>
+
+#include <linux/fb.h>
+#include <linux/vmalloc.h>
+#include <linux/backlight.h>
+#include <linux/lcd.h>
+
+#include <linux/leds.h>
+
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+
+#include <linux/completion.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+
+#include "hid-picolcd.h"
+
+
+void picolcd_leds_set(struct picolcd_data *data)
+{
+	struct hid_report *report;
+	unsigned long flags;
+
+	if (!data->led[0])
+		return;
+	report = picolcd_out_report(REPORT_LED_STATE, data->hdev);
+	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
+		return;
+
+	spin_lock_irqsave(&data->lock, flags);
+	hid_set_field(report->field[0], 0, data->led_state);
+	usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
+	spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static void picolcd_led_set_brightness(struct led_classdev *led_cdev,
+			enum led_brightness value)
+{
+	struct device *dev;
+	struct hid_device *hdev;
+	struct picolcd_data *data;
+	int i, state = 0;
+
+	dev  = led_cdev->dev->parent;
+	hdev = container_of(dev, struct hid_device, dev);
+	data = hid_get_drvdata(hdev);
+	for (i = 0; i < 8; i++) {
+		if (led_cdev != data->led[i])
+			continue;
+		state = (data->led_state >> i) & 1;
+		if (value == LED_OFF && state) {
+			data->led_state &= ~(1 << i);
+			picolcd_leds_set(data);
+		} else if (value != LED_OFF && !state) {
+			data->led_state |= 1 << i;
+			picolcd_leds_set(data);
+		}
+		break;
+	}
+}
+
+static enum led_brightness picolcd_led_get_brightness(struct led_classdev *led_cdev)
+{
+	struct device *dev;
+	struct hid_device *hdev;
+	struct picolcd_data *data;
+	int i, value = 0;
+
+	dev  = led_cdev->dev->parent;
+	hdev = container_of(dev, struct hid_device, dev);
+	data = hid_get_drvdata(hdev);
+	for (i = 0; i < 8; i++)
+		if (led_cdev == data->led[i]) {
+			value = (data->led_state >> i) & 1;
+			break;
+		}
+	return value ? LED_FULL : LED_OFF;
+}
+
+int picolcd_init_leds(struct picolcd_data *data, struct hid_report *report)
+{
+	struct device *dev = &data->hdev->dev;
+	struct led_classdev *led;
+	size_t name_sz = strlen(dev_name(dev)) + 8;
+	char *name;
+	int i, ret = 0;
+
+	if (!report)
+		return -ENODEV;
+	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
+			report->field[0]->report_size != 8) {
+		dev_err(dev, "unsupported LED_STATE report");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < 8; i++) {
+		led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
+		if (!led) {
+			dev_err(dev, "can't allocate memory for LED %d\n", i);
+			ret = -ENOMEM;
+			goto err;
+		}
+		name = (void *)(&led[1]);
+		snprintf(name, name_sz, "%s::GPO%d", dev_name(dev), i);
+		led->name = name;
+		led->brightness = 0;
+		led->max_brightness = 1;
+		led->brightness_get = picolcd_led_get_brightness;
+		led->brightness_set = picolcd_led_set_brightness;
+
+		data->led[i] = led;
+		ret = led_classdev_register(dev, data->led[i]);
+		if (ret) {
+			data->led[i] = NULL;
+			kfree(led);
+			dev_err(dev, "can't register LED %d\n", i);
+			goto err;
+		}
+	}
+	return 0;
+err:
+	for (i = 0; i < 8; i++)
+		if (data->led[i]) {
+			led = data->led[i];
+			data->led[i] = NULL;
+			led_classdev_unregister(led);
+			kfree(led);
+		}
+	return ret;
+}
+
+void picolcd_exit_leds(struct picolcd_data *data)
+{
+	struct led_classdev *led;
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		led = data->led[i];
+		data->led[i] = NULL;
+		if (!led)
+			continue;
+		led_classdev_unregister(led);
+		kfree(led);
+	}
+}
+
+