radeon: expose backlight class device for legacy LVDS encoder

Allows e.g. power management daemons to control the backlight level. Inspired
by the corresponding code in radeonfb.

[mjg@redhat.com: updated to add backlight type and make the connector the parent device]
Signed-off-by: Michel Dänzer <michel@daenzer.net>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Acked-by: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/gpu/drm/radeon/Kconfig b/drivers/gpu/drm/radeon/Kconfig
index 1c02d23..9746fee 100644 (file)
--- a/drivers/gpu/drm/radeon/Kconfig
+++ b/drivers/gpu/drm/radeon/Kconfig
@@ -1,6 +1,7 @@
 config DRM_RADEON_KMS
        bool "Enable modesetting on radeon by default - NEW DRIVER"
        depends on DRM_RADEON
+       select BACKLIGHT_CLASS_DEVICE
        help
          Choose this option if you want kernel modesetting enabled by default.
 

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 3f3c9aa..28c7961 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -40,6 +40,10 @@ radeon_atombios_connected_scratch_regs(struct drm_connector *connector,
                                       struct drm_encoder *encoder,
                                       bool connected);
 
+extern void
+radeon_legacy_backlight_init(struct radeon_encoder *radeon_encoder,
+                            struct drm_connector *drm_connector);
+
 void radeon_connector_hotplug(struct drm_connector *connector)
 {
        struct drm_device *dev = connector->dev;
@@ -1526,6 +1530,17 @@ radeon_add_legacy_connector(struct drm_device *dev,
                connector->polled = DRM_CONNECTOR_POLL_HPD;
        connector->display_info.subpixel_order = subpixel_order;
        drm_sysfs_connector_add(connector);
+       if (connector_type == DRM_MODE_CONNECTOR_LVDS) {
+               struct drm_encoder *drm_encoder;
+
+               list_for_each_entry(drm_encoder, &dev->mode_config.encoder_list, head) {
+                       struct radeon_encoder *radeon_encoder;
+
+                       radeon_encoder = to_radeon_encoder(drm_encoder);
+                       if (radeon_encoder->encoder_id == ENCODER_OBJECT_ID_INTERNAL_LVDS)
+                               radeon_legacy_backlight_init(radeon_encoder, connector);
+               }
+       }
        return;
 
 failed:

diff --git a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
index 59f834b..5b54268 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
@@ -28,6 +28,10 @@
 #include "radeon_drm.h"
 #include "radeon.h"
 #include "atom.h"
+#include <linux/backlight.h>
+#ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/backlight.h>
+#endif
 
 static void radeon_legacy_encoder_disable(struct drm_encoder *encoder)
 {
@@ -39,7 +43,7 @@ static void radeon_legacy_encoder_disable(struct drm_encoder *encoder)
        radeon_encoder->active_device = 0;
 }
 
-static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
+static void radeon_legacy_lvds_update(struct drm_encoder *encoder, int mode)
 {
        struct drm_device *dev = encoder->dev;
        struct radeon_device *rdev = dev->dev_private;
@@ -47,15 +51,23 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
        uint32_t lvds_gen_cntl, lvds_pll_cntl, pixclks_cntl, disp_pwr_man;
        int panel_pwr_delay = 2000;
        bool is_mac = false;
+       uint8_t backlight_level;
        DRM_DEBUG_KMS("\n");
 
+       lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
+       backlight_level = (lvds_gen_cntl >> RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
        if (radeon_encoder->enc_priv) {
                if (rdev->is_atom_bios) {
                        struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
                        panel_pwr_delay = lvds->panel_pwr_delay;
+                       if (lvds->bl_dev)
+                               backlight_level = lvds->backlight_level;
                } else {
                        struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
                        panel_pwr_delay = lvds->panel_pwr_delay;
+                       if (lvds->bl_dev)
+                               backlight_level = lvds->backlight_level;
                }
        }
 
@@ -82,11 +94,13 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
                lvds_pll_cntl &= ~RADEON_LVDS_PLL_RESET;
                WREG32(RADEON_LVDS_PLL_CNTL, lvds_pll_cntl);
 
-               lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
-               lvds_gen_cntl |= (RADEON_LVDS_ON | RADEON_LVDS_EN | RADEON_LVDS_DIGON | RADEON_LVDS_BLON);
+               lvds_gen_cntl &= ~(RADEON_LVDS_DISPLAY_DIS |
+                                  RADEON_LVDS_BL_MOD_LEVEL_MASK);
+               lvds_gen_cntl |= (RADEON_LVDS_ON | RADEON_LVDS_EN |
+                                 RADEON_LVDS_DIGON | RADEON_LVDS_BLON |
+                                 (backlight_level << RADEON_LVDS_BL_MOD_LEVEL_SHIFT));
                if (is_mac)
                        lvds_gen_cntl |= RADEON_LVDS_BL_MOD_EN;
-               lvds_gen_cntl &= ~(RADEON_LVDS_DISPLAY_DIS);
                udelay(panel_pwr_delay * 1000);
                WREG32(RADEON_LVDS_GEN_CNTL, lvds_gen_cntl);
                break;
@@ -95,7 +109,6 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
        case DRM_MODE_DPMS_OFF:
                pixclks_cntl = RREG32_PLL(RADEON_PIXCLKS_CNTL);
                WREG32_PLL_P(RADEON_PIXCLKS_CNTL, 0, ~RADEON_PIXCLK_LVDS_ALWAYS_ONb);
-               lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
                lvds_gen_cntl |= RADEON_LVDS_DISPLAY_DIS;
                if (is_mac) {
                        lvds_gen_cntl &= ~RADEON_LVDS_BL_MOD_EN;
@@ -119,6 +132,25 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
 
 }
 
+static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
+{
+       struct radeon_device *rdev = encoder->dev->dev_private;
+       struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
+       DRM_DEBUG("\n");
+
+       if (radeon_encoder->enc_priv) {
+               if (rdev->is_atom_bios) {
+                       struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+                       lvds->dpms_mode = mode;
+               } else {
+                       struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+                       lvds->dpms_mode = mode;
+               }
+       }
+
+       radeon_legacy_lvds_update(encoder, mode);
+}
+
 static void radeon_legacy_lvds_prepare(struct drm_encoder *encoder)
 {
        struct radeon_device *rdev = encoder->dev->dev_private;
@@ -237,9 +269,222 @@ static const struct drm_encoder_helper_funcs radeon_legacy_lvds_helper_funcs = {
        .disable = radeon_legacy_encoder_disable,
 };
 
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+
+#define MAX_RADEON_LEVEL 0xFF
+
+struct radeon_backlight_privdata {
+       struct radeon_encoder *encoder;
+       uint8_t negative;
+};
+
+static uint8_t radeon_legacy_lvds_level(struct backlight_device *bd)
+{
+       struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+       uint8_t level;
+
+       /* Convert brightness to hardware level */
+       if (bd->props.brightness < 0)
+               level = 0;
+       else if (bd->props.brightness > MAX_RADEON_LEVEL)
+               level = MAX_RADEON_LEVEL;
+       else
+               level = bd->props.brightness;
+
+       if (pdata->negative)
+               level = MAX_RADEON_LEVEL - level;
+
+       return level;
+}
+
+static int radeon_legacy_backlight_update_status(struct backlight_device *bd)
+{
+       struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+       struct radeon_encoder *radeon_encoder = pdata->encoder;
+       struct drm_device *dev = radeon_encoder->base.dev;
+       struct radeon_device *rdev = dev->dev_private;
+       int dpms_mode = DRM_MODE_DPMS_ON;
+
+       if (radeon_encoder->enc_priv) {
+               if (rdev->is_atom_bios) {
+                       struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+                       dpms_mode = lvds->dpms_mode;
+                       lvds->backlight_level = radeon_legacy_lvds_level(bd);
+               } else {
+                       struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+                       dpms_mode = lvds->dpms_mode;
+                       lvds->backlight_level = radeon_legacy_lvds_level(bd);
+               }
+       }
+
+       if (bd->props.brightness > 0)
+               radeon_legacy_lvds_update(&radeon_encoder->base, dpms_mode);
+       else
+               radeon_legacy_lvds_update(&radeon_encoder->base, DRM_MODE_DPMS_OFF);
+
+       return 0;
+}
+
+static int radeon_legacy_backlight_get_brightness(struct backlight_device *bd)
+{
+       struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+       struct radeon_encoder *radeon_encoder = pdata->encoder;
+       struct drm_device *dev = radeon_encoder->base.dev;
+       struct radeon_device *rdev = dev->dev_private;
+       uint8_t backlight_level;
+
+       backlight_level = (RREG32(RADEON_LVDS_GEN_CNTL) >>
+                          RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
+       return pdata->negative ? MAX_RADEON_LEVEL - backlight_level : backlight_level;
+}
+
+static const struct backlight_ops radeon_backlight_ops = {
+       .get_brightness = radeon_legacy_backlight_get_brightness,
+       .update_status  = radeon_legacy_backlight_update_status,
+};
+
+void radeon_legacy_backlight_init(struct radeon_encoder *radeon_encoder,
+                                 struct drm_connector *drm_connector)
+{
+       struct drm_device *dev = radeon_encoder->base.dev;
+       struct radeon_device *rdev = dev->dev_private;
+       struct backlight_device *bd;
+       struct backlight_properties props;
+       struct radeon_backlight_privdata *pdata;
+       uint8_t backlight_level;
+
+       if (!radeon_encoder->enc_priv)
+               return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+       if (!pmac_has_backlight_type("ati") &&
+           !pmac_has_backlight_type("mnca"))
+               return;
+#endif
+
+       pdata = kmalloc(sizeof(struct radeon_backlight_privdata), GFP_KERNEL);
+       if (!pdata) {
+               DRM_ERROR("Memory allocation failed\n");
+               goto error;
+       }
+
+       props.max_brightness = MAX_RADEON_LEVEL;
+       props.type = BACKLIGHT_RAW;
+       bd = backlight_device_register("radeon_bl", &drm_connector->kdev,
+                                      pdata, &radeon_backlight_ops, &props);
+       if (IS_ERR(bd)) {
+               DRM_ERROR("Backlight registration failed\n");
+               goto error;
+       }
+
+       pdata->encoder = radeon_encoder;
+
+       backlight_level = (RREG32(RADEON_LVDS_GEN_CNTL) >>
+                          RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
+       /* First, try to detect backlight level sense based on the assumption
+        * that firmware set it up at full brightness
+        */
+       if (backlight_level == 0)
+               pdata->negative = true;
+       else if (backlight_level == 0xff)
+               pdata->negative = false;
+       else {
+               /* XXX hack... maybe some day we can figure out in what direction
+                * backlight should work on a given panel?
+                */
+               pdata->negative = (rdev->family != CHIP_RV200 &&
+                                  rdev->family != CHIP_RV250 &&
+                                  rdev->family != CHIP_RV280 &&
+                                  rdev->family != CHIP_RV350);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+               pdata->negative = (pdata->negative ||
+                                  of_machine_is_compatible("PowerBook4,3") ||
+                                  of_machine_is_compatible("PowerBook6,3") ||
+                                  of_machine_is_compatible("PowerBook6,5"));
+#endif
+       }
+
+       if (rdev->is_atom_bios) {
+               struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+               lvds->bl_dev = bd;
+       } else {
+               struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+               lvds->bl_dev = bd;
+       }
+
+       bd->props.brightness = radeon_legacy_backlight_get_brightness(bd);
+       bd->props.power = FB_BLANK_UNBLANK;
+       backlight_update_status(bd);
+
+       DRM_INFO("radeon legacy LVDS backlight initialized\n");
+
+       return;
+
+error:
+       kfree(pdata);
+       return;
+}
+
+static void radeon_legacy_backlight_exit(struct radeon_encoder *radeon_encoder)
+{
+       struct drm_device *dev = radeon_encoder->base.dev;
+       struct radeon_device *rdev = dev->dev_private;
+       struct backlight_device *bd = NULL;
+
+       if (!radeon_encoder->enc_priv)
+               return;
+
+       if (rdev->is_atom_bios) {
+               struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+               bd = lvds->bl_dev;
+               lvds->bl_dev = NULL;
+       } else {
+               struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+               bd = lvds->bl_dev;
+               lvds->bl_dev = NULL;
+       }
+
+       if (bd) {
+               struct radeon_legacy_backlight_privdata *pdata;
+
+               pdata = bl_get_data(bd);
+               backlight_device_unregister(bd);
+               kfree(pdata);
+
+               DRM_INFO("radeon legacy LVDS backlight unloaded\n");
+       }
+}
+
+#else /* !CONFIG_BACKLIGHT_CLASS_DEVICE */
+
+void radeon_legacy_backlight_init(struct radeon_encoder *encoder)
+{
+}
+
+static void radeon_legacy_backlight_exit(struct radeon_encoder *encoder)
+{
+}
+
+#endif
+
+
+static void radeon_lvds_enc_destroy(struct drm_encoder *encoder)
+{
+       struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
+
+       if (radeon_encoder->enc_priv) {
+               radeon_legacy_backlight_exit(radeon_encoder);
+               kfree(radeon_encoder->enc_priv);
+       }
+       drm_encoder_cleanup(encoder);
+       kfree(radeon_encoder);
+}
 
 static const struct drm_encoder_funcs radeon_legacy_lvds_enc_funcs = {
-       .destroy = radeon_enc_destroy,
+       .destroy = radeon_lvds_enc_destroy,
 };
 
 static void radeon_legacy_primary_dac_dpms(struct drm_encoder *encoder, int mode)

diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index 5067d18..e458281 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -302,6 +302,9 @@ struct radeon_encoder_lvds {
        uint32_t lvds_gen_cntl;
        /* panel mode */
        struct drm_display_mode native_mode;
+       struct backlight_device *bl_dev;
+       int      dpms_mode;
+       uint8_t  backlight_level;
 };
 
 struct radeon_encoder_tv_dac {
@@ -355,6 +358,9 @@ struct radeon_encoder_atom_dig {
        uint32_t lcd_ss_id;
        /* panel mode */
        struct drm_display_mode native_mode;
+       struct backlight_device *bl_dev;
+       int dpms_mode;
+       uint8_t backlight_level;
 };
 
 struct radeon_encoder_atom_dac {