[PATCH v3 4/6] hid: add lcd support to PicoLCD device

Bruno Prémont
2010-03-24T23:01:22Z

Add lcd support to PicoLCD device.

LCD support depends on lcd class and is only being
compiled if lcd class has been selected.

Changes since v2:
- Drop inline keyword on non-stub functions

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
---
drivers/hid/Kconfig | 2 +-
drivers/hid/hid-picolcd.c | 109 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 110 insertions(+), 1 deletions(-)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 588b9ac..399edc5 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -279,8 +279,8 @@ config HID_PICOLCD
- Switching between Firmware and Flash mode
- Framebuffer for monochrome 256x64 display
- Backlight control (needs CONFIG_BACKLIGHT_CLASS_DEVICE)
+ - Contrast control (needs CONFIG_LCD_CLASS_DEVICE)
Features that are not (yet) supported:
- - Contrast control
- IR
- General purpose outputs
- EEProm / Flash access
diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index 2417a9d..0cc0d71 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -27,6 +27,7 @@
#include <linux/fb.h>
#include <linux/vmalloc.h>
#include <linux/backlight.h>
+#include <linux/lcd.h>

#include <linux/seq_file.h>
#include <linux/debugfs.h>
@@ -184,6 +185,10 @@ struct picolcd_data {
struct fb_info *fb_info;
struct fb_deferred_io fb_defio;
#endif /* CONFIG_FB */
+#if defined(CONFIG_LCD_CLASS_DEVICE) || defined(CONFIG_LCD_CLASS_DEVICE_MODULE)
+ struct lcd_device *lcd;
+ u8 lcd_contrast;
+#endif
#if defined(CONFIG_BACKLIGHT_CLASS_DEVICE) || defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE)
struct backlight_device *backlight;
u8 lcd_brightness;
@@ -836,6 +841,99 @@ static void picolcd_suspend_backlight(struct picolcd_data *data)
}
#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */

+#if defined(CONFIG_LCD_CLASS_DEVICE) || defined(CONFIG_LCD_CLASS_DEVICE_MODULE)
+/*
+ * 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,
+};
+
+static 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;
+}
+
+static void picolcd_exit_lcd(struct picolcd_data *data)
+{
+ struct lcd_device *ldev = data->lcd;
+
+ data->lcd = NULL;
+ if (ldev)
+ lcd_device_unregister(ldev);
+}
+
+static inline int picolcd_resume_lcd(struct picolcd_data *data)
+{
+ if (!data->lcd)
+ return 0;
+ return picolcd_set_contrast(data->lcd, data->lcd_contrast);
+}
+#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_LCD_CLASS_DEVICE */
+
/*
* input class device
*/
@@ -971,6 +1069,7 @@ static int picolcd_reset(struct hid_device *hdev)
if (error)
return error;

+ picolcd_resume_lcd(data);
picolcd_resume_backlight(data);
#if defined(CONFIG_FB) || defined(CONFIG_FB_MODULE)
if (data->fb_info)
@@ -1589,6 +1688,9 @@ static int picolcd_reset_resume(struct hid_device *hdev)
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);
@@ -1696,6 +1798,11 @@ static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data)
if (error)
goto err;

+ /* Setup lcd class device */
+ error = picolcd_init_lcd(data, picolcd_out_report(REPORT_CONTRAST, hdev));
+ if (error)
+ goto err;
+
/* Setup backlight class device */
error = picolcd_init_backlight(data, picolcd_out_report(REPORT_BRIGHTNESS, hdev));
if (error)
@@ -1711,6 +1818,7 @@ static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data)
return 0;
err:
picolcd_exit_backlight(data);
+ picolcd_exit_lcd(data);
picolcd_exit_framebuffer(data);
picolcd_exit_cir(data);
picolcd_exit_keys(data);
@@ -1843,6 +1951,7 @@ static void picolcd_remove(struct hid_device *hdev)

/* Clean up the framebuffer */
picolcd_exit_backlight(data);
+ picolcd_exit_lcd(data);
picolcd_exit_framebuffer(data);
/* Cleanup input */
picolcd_exit_cir(data);
--
1.6.4.4