HID: add PM support to PicoLCD device

Add PM support in order to turn off backlight on suspend, restore
it on resume and especially restore complete state on reset-resume.

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 74 insertions, 5 deletions

diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index aa6f2e18d4a6..95253b310541 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -763,7 +763,7 @@ static inline int picolcd_init_framebuffer(struct picolcd_data *data)
 {
         return 0;
 }
-static void picolcd_exit_framebuffer(struct picolcd_data *data)
+static inline void picolcd_exit_framebuffer(struct picolcd_data *data)
 {
 }
 #define picolcd_fbinfo(d) NULL
@@ -852,6 +852,18 @@ static inline int picolcd_resume_backlight(struct picolcd_data *data)
         return picolcd_set_brightness(data->backlight);
 }
 
+#ifdef CONFIG_PM
+static 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 */
 #else
 static inline int picolcd_init_backlight(struct picolcd_data *data,
                 struct hid_report *report)
@@ -865,6 +877,9 @@ 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
@@ -1098,7 +1113,7 @@ static inline int picolcd_init_leds(struct picolcd_data *data,
 {
         return 0;
 }
-static void picolcd_exit_leds(struct picolcd_data *data)
+static inline void picolcd_exit_leds(struct picolcd_data *data)
 {
 }
 static inline int picolcd_leds_set(struct picolcd_data *data)
@@ -2214,9 +2229,18 @@ static void picolcd_exit_devfs(struct picolcd_data *data)
         mutex_destroy(&data->mutex_flash);
 }
 #else
-#define picolcd_debug_raw_event(data, hdev, report, raw_data, size)
-#define picolcd_init_devfs(data, eeprom_r, eeprom_w, flash_r, flash_w, reset)
-static 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)
+{
+}
+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)
 {
 }
 #endif /* CONFIG_DEBUG_FS */
@@ -2259,6 +2283,46 @@ static int picolcd_raw_event(struct hid_device *hdev,
         return 1;
 }
 
+#ifdef CONFIG_PM
+static int picolcd_suspend(struct hid_device *hdev, pm_message_t message)
+{
+        if (message.event & PM_EVENT_AUTO)
+                return 0;
+
+        picolcd_suspend_backlight(hid_get_drvdata(hdev));
+        dbg_hid(PICOLCD_NAME " device ready for suspend\n");
+        return 0;
+}
+
+static int picolcd_resume(struct hid_device *hdev)
+{
+        int ret;
+        ret = picolcd_resume_backlight(hid_get_drvdata(hdev));
+        if (ret)
+                dbg_hid(PICOLCD_NAME " restoring backlight failed: %d\n", ret);
+        return 0;
+}
+
+static int picolcd_reset_resume(struct hid_device *hdev)
+{
+        int ret;
+        ret = picolcd_reset(hdev);
+        if (ret)
+                dbg_hid(PICOLCD_NAME " resetting our device failed: %d\n", ret);
+        ret = picolcd_fb_reset(hid_get_drvdata(hdev), 0);
+        if (ret)
+                dbg_hid(PICOLCD_NAME " restoring framebuffer content failed: %d\n", ret);
+        ret = picolcd_resume_lcd(hid_get_drvdata(hdev));
+        if (ret)
+                dbg_hid(PICOLCD_NAME " restoring lcd failed: %d\n", ret);
+        ret = picolcd_resume_backlight(hid_get_drvdata(hdev));
+        if (ret)
+                dbg_hid(PICOLCD_NAME " restoring backlight failed: %d\n", ret);
+        picolcd_leds_set(hid_get_drvdata(hdev));
+        return 0;
+}
+#endif
+
 /* initialize keypad input device */
 static int picolcd_init_keys(struct picolcd_data *data,
                 struct hid_report *report)
@@ -2544,6 +2608,11 @@ static struct hid_driver picolcd_driver = {
         .probe =         picolcd_probe,
         .remove =        picolcd_remove,
         .raw_event =     picolcd_raw_event,
+#ifdef CONFIG_PM
+        .suspend =       picolcd_suspend,
+        .resume =        picolcd_resume,
+        .reset_resume =  picolcd_reset_resume,
+#endif
 };
 
 static int __init picolcd_init(void)