From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Thomas=20Niederpr=C3=BCm?= Date: Tue, 24 Mar 2015 21:23:57 +0000 Subject: [PATCHv5 10/11] fbdev: ssd1307fb: add backlight controls for setting the contrast Message-Id: <1427232238-21099-11-git-send-email-niederp@physik.uni-kl.de> List-Id: References: <1423261694-5939-1-git-send-email-niederp@physik.uni-kl.de> <1427232238-21099-1-git-send-email-niederp@physik.uni-kl.de> In-Reply-To: <1427232238-21099-1-git-send-email-niederp@physik.uni-kl.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, maxime.ripard@free-electrons.com, kernel@pengutronix.de, shawn.guo@linaro.org, robh+dt@kernel.org Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Thomas=20Niederpr=C3=BCm?= The backlight class is used to create userspace handles for setting the OLED contrast. Signed-off-by: Thomas Niederpr=C3=BCm Acked-by: Maxime Ripard --- drivers/video/fbdev/Kconfig | 1 + drivers/video/fbdev/ssd1307fb.c | 58 +++++++++++++++++++++++++++++++++++++= ++++ 2 files changed, 59 insertions(+) diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig index b3dd417..da70bae 100644 --- a/drivers/video/fbdev/Kconfig +++ b/drivers/video/fbdev/Kconfig @@ -2478,6 +2478,7 @@ config FB_SSD1307 select FB_SYS_IMAGEBLIT select FB_DEFERRED_IO select PWM + select FB_BACKLIGHT help This driver implements support for the Solomon SSD1307 OLED controller over I2C. diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307f= b.c index d5aec5c..061cc95 100644 --- a/drivers/video/fbdev/ssd1307fb.c +++ b/drivers/video/fbdev/ssd1307fb.c @@ -7,6 +7,7 @@ */ =20 #include +#include #include #include #include @@ -38,6 +39,8 @@ #define SSD1307FB_SET_COM_PINS_CONFIG 0xda #define SSD1307FB_SET_VCOMH 0xdb =20 +#define MAX_CONTRAST 255 + #define REFRESHRATE 1 =20 static u_int refreshrate =3D REFRESHRATE; @@ -428,6 +431,43 @@ static int ssd1307fb_init(struct ssd1307fb_par *par) return 0; } =20 +static int ssd1307fb_update_bl(struct backlight_device *bdev) +{ + struct ssd1307fb_par *par =3D bl_get_data(bdev); + int ret; + int brightness =3D bdev->props.brightness; + + par->contrast =3D brightness; + + ret =3D ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST); + if (ret < 0) + return ret; + ret =3D ssd1307fb_write_cmd(par->client, par->contrast); + if (ret < 0) + return ret; + return 0; +} + +static int ssd1307fb_get_brightness(struct backlight_device *bdev) +{ + struct ssd1307fb_par *par =3D bl_get_data(bdev); + + return par->contrast; +} + +static int ssd1307fb_check_fb(struct backlight_device *bdev, + struct fb_info *info) +{ + return (info->bl_dev =3D bdev); +} + +static const struct backlight_ops ssd1307fb_bl_ops =3D { + .options =3D BL_CORE_SUSPENDRESUME, + .update_status =3D ssd1307fb_update_bl, + .get_brightness =3D ssd1307fb_get_brightness, + .check_fb =3D ssd1307fb_check_fb, +}; + static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo =3D { .default_vcomh =3D 0x34, .default_dclk_div =3D 0, @@ -472,6 +512,8 @@ MODULE_DEVICE_TABLE(of, ssd1307fb_of_match); static int ssd1307fb_probe(struct i2c_client *client, const struct i2c_device_id *id) { + struct backlight_device *bl; + char bl_name[12]; struct fb_info *info; struct device_node *node =3D client->dev.of_node; struct fb_deferred_io *ssd1307fb_defio; @@ -607,10 +649,24 @@ static int ssd1307fb_probe(struct i2c_client *client, goto panel_init_error; } =20 + snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node); + bl =3D backlight_device_register(bl_name, &client->dev, par, + &ssd1307fb_bl_ops, NULL); + bl->props.brightness =3D contrast; + bl->props.max_brightness =3D MAX_CONTRAST; + info->bl_dev =3D bl; + + if (IS_ERR(bl)) { + dev_err(&client->dev, "unable to register backlight device: %ld\n", + PTR_ERR(bl)); + goto bl_init_error; + } dev_info(&client->dev, "fb%d: %s framebuffer device registered, using %d = bytes of video memory\n", info->node, info->fix.id, vmem_size); =20 return 0; =20 +bl_init_error: + unregister_framebuffer(info); panel_init_error: if (par->device_info->need_pwm) { pwm_disable(par->pwm); @@ -630,6 +686,8 @@ static int ssd1307fb_remove(struct i2c_client *client) =20 ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF); =20 + backlight_device_unregister(info->bl_dev); + unregister_framebuffer(info); if (par->device_info->need_pwm) { pwm_disable(par->pwm); --=20 2.3.0