diff options
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 347 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_display_types.h | 5 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 285 | ||||
| -rw-r--r-- | include/drm/drm_dp_helper.h | 48 |
4 files changed, 427 insertions, 258 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 55b53df6ce34..24bbc710c825 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -3115,3 +3115,350 @@ int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc) return 0; } EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr); + +/** + * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel via AUX + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * @level: The brightness level to set + * + * Sets the brightness level of an eDP panel's backlight. Note that the panel's backlight must + * already have been enabled by the driver by calling drm_edp_backlight_enable(). + * + * Returns: %0 on success, negative error code on failure + */ +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level) +{ + int ret; + u8 buf[2] = { 0 }; + + if (bl->lsb_reg_used) { + buf[0] = (level & 0xff00) >> 8; + buf[1] = (level & 0x00ff); + } else { + buf[0] = level; + } + + ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + drm_err(aux->drm_dev, + "%s: Failed to write aux backlight level: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_set_level); + +static int +drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + bool enable) +{ + int ret; + u8 buf; + + /* The panel uses something other then DPCD for enabling its backlight */ + if (!bl->aux_enable) + return 0; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, &buf); + if (ret != 1) { + drm_err(aux->drm_dev, "%s: Failed to read eDP display control register: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + if (enable) + buf |= DP_EDP_BACKLIGHT_ENABLE; + else + buf &= ~DP_EDP_BACKLIGHT_ENABLE; + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf); + if (ret != 1) { + drm_err(aux->drm_dev, "%s: Failed to write eDP display control register: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + return 0; +} + +/** + * drm_edp_backlight_enable() - Enable an eDP panel's backlight using DPCD + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * @level: The initial backlight level to set via AUX, if there is one + * + * This function handles enabling DPCD backlight controls on a panel over DPCD, while additionally + * restoring any important backlight state such as the given backlight level, the brightness byte + * count, backlight frequency, etc. + * + * Note that certain panels, while supporting brightness level controls over DPCD, may not support + * having their backlights enabled via the standard %DP_EDP_DISPLAY_CONTROL_REGISTER. On such panels + * &drm_edp_backlight_info.aux_enable will be set to %false, this function will skip the step of + * programming the %DP_EDP_DISPLAY_CONTROL_REGISTER, and the driver must perform the required + * implementation specific step for enabling the backlight after calling this function. + * + * Returns: %0 on success, negative error code on failure. + */ +int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + const u16 level) +{ + int ret; + u8 dpcd_buf, new_dpcd_buf; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, + "%s: Failed to read backlight mode: %d\n", aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + new_dpcd_buf = dpcd_buf; + + if ((dpcd_buf & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) != DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { + new_dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK; + new_dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, bl->pwmgen_bit_count); + if (ret != 1) + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n", + aux->name, ret); + } + + if (bl->pwm_freq_pre_divider) { + ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_FREQ_SET, bl->pwm_freq_pre_divider); + if (ret != 1) + drm_dbg_kms(aux->drm_dev, + "%s: Failed to write aux backlight frequency: %d\n", + aux->name, ret); + else + new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; + } + + if (new_dpcd_buf != dpcd_buf) { + ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux backlight mode: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + } + + ret = drm_edp_backlight_set_level(aux, bl, level); + if (ret < 0) + return ret; + ret = drm_edp_backlight_set_enable(aux, bl, true); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_enable); + +/** + * drm_edp_backlight_disable() - Disable an eDP backlight using DPCD, if supported + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * + * This function handles disabling DPCD backlight controls on a panel over AUX. Note that some + * panels have backlights that are enabled/disabled by other means, despite having their brightness + * values controlled through DPCD. On such panels &drm_edp_backlight_info.aux_enable will be set to + * %false, this function will become a no-op (and we will skip updating + * %DP_EDP_DISPLAY_CONTROL_REGISTER), and the driver must take care to perform it's own + * implementation specific step for disabling the backlight. + * + * Returns: %0 on success or no-op, negative error code on failure. + */ +int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl) +{ + int ret; + + ret = drm_edp_backlight_set_enable(aux, bl, false); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_disable); + +static inline int +drm_edp_backlight_probe_max(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]) +{ + int fxp, fxp_min, fxp_max, fxp_actual, f = 1; + int ret; + u8 pn, pn_min, pn_max; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT, &pn); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap: %d\n", + aux->name, ret); + return -ENODEV; + } + + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + bl->max = (1 << pn) - 1; + if (!driver_pwm_freq_hz) + return 0; + + /* + * Set PWM Frequency divider to match desired frequency provided by the driver. + * The PWM Frequency is calculated as 27Mhz / (F x P). + * - Where F = PWM Frequency Pre-Divider value programmed by field 7:0 of the + * EDP_BACKLIGHT_FREQ_SET register (DPCD Address 00728h) + * - Where P = 2^Pn, where Pn is the value programmed by field 4:0 of the + * EDP_PWMGEN_BIT_COUNT register (DPCD Address 00724h) + */ + + /* Find desired value of (F x P) + * Note that, if F x P is out of supported range, the maximum value or minimum value will + * applied automatically. So no need to check that. + */ + fxp = DIV_ROUND_CLOSEST(1000 * DP_EDP_BACKLIGHT_FREQ_BASE_KHZ, driver_pwm_freq_hz); + + /* Use highest possible value of Pn for more granularity of brightness adjustment while + * satifying the conditions below. + * - Pn is in the range of Pn_min and Pn_max + * - F is in the range of 1 and 255 + * - FxP is within 25% of desired value. + * Note: 25% is arbitrary value and may need some tweak. + */ + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &pn_min); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap min: %d\n", + aux->name, ret); + return 0; + } + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX, &pn_max); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap max: %d\n", + aux->name, ret); + return 0; + } + pn_min &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + pn_max &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + + /* Ensure frequency is within 25% of desired value */ + fxp_min = DIV_ROUND_CLOSEST(fxp * 3, 4); + fxp_max = DIV_ROUND_CLOSEST(fxp * 5, 4); + if (fxp_min < (1 << pn_min) || (255 << pn_max) < fxp_max) { + drm_dbg_kms(aux->drm_dev, + "%s: Driver defined backlight frequency (%d) out of range\n", + aux->name, driver_pwm_freq_hz); + return 0; + } + + for (pn = pn_max; pn >= pn_min; pn--) { + f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); + fxp_actual = f << pn; + if (fxp_min <= fxp_actual && fxp_actual <= fxp_max) + break; + } + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, pn); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n", + aux->name, ret); + return 0; + } + bl->pwmgen_bit_count = pn; + bl->max = (1 << pn) - 1; + + if (edp_dpcd[2] & DP_EDP_BACKLIGHT_FREQ_AUX_SET_CAP) { + bl->pwm_freq_pre_divider = f; + drm_dbg_kms(aux->drm_dev, "%s: Using backlight frequency from driver (%dHz)\n", + aux->name, driver_pwm_freq_hz); + } + + return 0; +} + +static inline int +drm_edp_backlight_probe_level(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u8 *current_mode) +{ + int ret; + u8 buf[2]; + u8 mode_reg; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &mode_reg); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read backlight mode: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + *current_mode = (mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK); + if (*current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { + int size = 1 + bl->lsb_reg_used; + + ret = drm_dp_dpcd_read(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf, size); + if (ret != size) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read backlight level: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + if (bl->lsb_reg_used) + return (buf[0] << 8) | buf[1]; + else + return buf[0]; + } + + /* + * If we're not in DPCD control mode yet, the programmed brightness value is meaningless and + * the driver should assume max brightness + */ + return bl->max; +} + +/** + * drm_edp_backlight_init() - Probe a display panel's TCON using the standard VESA eDP backlight + * interface. + * @aux: The DP aux device to use for probing + * @bl: The &drm_edp_backlight_info struct to fill out with information on the backlight + * @driver_pwm_freq_hz: Optional PWM frequency from the driver in hz + * @edp_dpcd: A cached copy of the eDP DPCD + * @current_level: Where to store the probed brightness level + * @current_mode: Where to store the currently set backlight control mode + * + * Initializes a &drm_edp_backlight_info struct by probing @aux for it's backlight capabilities, + * along with also probing the current and maximum supported brightness levels. + * + * If @driver_pwm_freq_hz is non-zero, this will be used as the backlight frequency. Otherwise, the + * default frequency from the panel is used. + * + * Returns: %0 on success, negative error code on failure. + */ +int +drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE], + u16 *current_level, u8 *current_mode) +{ + int ret; + + if (edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) + bl->aux_enable = true; + if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) + bl->lsb_reg_used = true; + + ret = drm_edp_backlight_probe_max(aux, bl, driver_pwm_freq_hz, edp_dpcd); + if (ret < 0) + return ret; + + ret = drm_edp_backlight_probe_level(aux, bl, current_mode); + if (ret < 0) + return ret; + *current_level = ret; + + drm_dbg_kms(aux->drm_dev, + "%s: Found backlight level=%d/%d pwm_freq_pre_divider=%d mode=%x\n", + aux->name, *current_level, bl->max, bl->pwm_freq_pre_divider, *current_mode); + drm_dbg_kms(aux->drm_dev, + "%s: Backlight caps: pwmgen_bit_count=%d lsb_reg_used=%d aux_enable=%d\n", + aux->name, bl->pwmgen_bit_count, bl->lsb_reg_used, bl->aux_enable); + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_init); diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index d4a57bce71b1..8696b39da2fe 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -310,10 +310,7 @@ struct intel_panel { /* DPCD backlight */ union { struct { - u8 pwmgen_bit_count; - u8 pwm_freq_pre_divider; - bool lsb_reg_used; - bool aux_enable; + struct drm_edp_backlight_info info; } vesa; struct { bool sdr_uses_aux; diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 95f2df631052..6ac568617ef3 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -270,114 +270,19 @@ intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pi } /* VESA backlight callbacks */ -static bool intel_dp_aux_vesa_backlight_dpcd_mode(struct intel_connector *connector) -{ - struct intel_dp *intel_dp = intel_attached_dp(connector); - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - int ret; - u8 mode_reg; - - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &mode_reg); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read backlight mode: %d\n", ret); - return false; - } - - return (mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) == - DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; -} - -/* - * Read the current backlight value from DPCD register(s) based - * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported - */ static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, enum pipe unused) { - struct intel_dp *intel_dp = intel_attached_dp(connector); - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - int ret; - u8 read_val[2] = { 0x0 }; - u16 level = 0; - - /* - * If we're not in DPCD control mode yet, the programmed brightness - * value is meaningless and we should assume max brightness - */ - if (!intel_dp_aux_vesa_backlight_dpcd_mode(connector)) - return connector->panel.backlight.max; - - ret = drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, &read_val, - sizeof(read_val)); - if (ret != sizeof(read_val)) { - drm_dbg_kms(&i915->drm, "Failed to read brightness level: %d\n", ret); - return 0; - } - - if (connector->panel.backlight.edp.vesa.lsb_reg_used) - level = (read_val[0] << 8 | read_val[1]); - else - level = read_val[0]; - - return level; + return connector->panel.backlight.level; } -/* - * Sends the current backlight level over the aux channel, checking if its using - * 8-bit or 16 bit value (MSB and LSB) - */ static void -intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, - u32 level) +intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, u32 level) { struct intel_connector *connector = to_intel_connector(conn_state->connector); - struct intel_dp *intel_dp = intel_attached_dp(connector); - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - int ret; - u8 vals[2] = { 0x0 }; - - /* Write the MSB and/or LSB */ - if (connector->panel.backlight.edp.vesa.lsb_reg_used) { - vals[0] = (level & 0xFF00) >> 8; - vals[1] = (level & 0xFF); - } else { - vals[0] = level; - } - - ret = drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, vals, - sizeof(vals)); - if (ret != sizeof(vals)) { - drm_dbg_kms(&i915->drm, "Failed to write aux backlight level: %d\n", ret); - return; - } -} - -static void set_vesa_backlight_enable(struct intel_connector *connector, bool enable) -{ - struct intel_dp *intel_dp = intel_attached_dp(connector); - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - int ret; - u8 reg_val = 0; - - /* Early return when display use other mechanism to enable backlight. */ - if (!connector->panel.backlight.edp.vesa.aux_enable) - return; - - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, ®_val); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read eDP display control register: %d\n", ret); - return; - } - - if (enable) - reg_val |= DP_EDP_BACKLIGHT_ENABLE; - else - reg_val &= ~(DP_EDP_BACKLIGHT_ENABLE); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); - ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, reg_val); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to %s aux backlight: %d\n", - enabledisable(enable), ret); - } + drm_edp_backlight_set_level(&intel_dp->aux, &panel->backlight.edp.vesa.info, level); } static void @@ -385,170 +290,46 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, const struct drm_connector_state *conn_state, u32 level) { struct intel_connector *connector = to_intel_connector(conn_state->connector); - struct intel_dp *intel_dp = intel_attached_dp(connector); - struct drm_i915_private *i915 = dp_to_i915(intel_dp); struct intel_panel *panel = &connector->panel; - int ret; - u8 dpcd_buf, new_dpcd_buf; - u8 pwmgen_bit_count = panel->backlight.edp.vesa.pwmgen_bit_count; - - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read backlight mode: %d\n", ret); - return; - } - - new_dpcd_buf = dpcd_buf; - - if ((dpcd_buf & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) != DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { - new_dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK; - new_dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; - - ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, pwmgen_bit_count); - if (ret != 1) - drm_dbg_kms(&i915->drm, "Failed to write aux pwmgen bit count: %d\n", ret); - } - - if (panel->backlight.edp.vesa.pwm_freq_pre_divider) { - ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_BACKLIGHT_FREQ_SET, - panel->backlight.edp.vesa.pwm_freq_pre_divider); - if (ret == 1) - new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; - else - drm_dbg_kms(&i915->drm, "Failed to write aux backlight frequency: %d\n", - ret); - } - - if (new_dpcd_buf != dpcd_buf) { - ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, - new_dpcd_buf); - if (ret != 1) - drm_dbg_kms(&i915->drm, "Failed to write aux backlight mode: %d\n", ret); - } + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); - intel_dp_aux_vesa_set_backlight(conn_state, level); - set_vesa_backlight_enable(connector, true); + drm_edp_backlight_enable(&intel_dp->aux, &panel->backlight.edp.vesa.info, level); } static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level) { - set_vesa_backlight_enable(to_intel_connector(old_conn_state->connector), false); -} - -/* - * Compute PWM frequency divider value based off the frequency provided to us by the vbt. - * The PWM Frequency is calculated as 27Mhz / (F x P). - * - Where F = PWM Frequency Pre-Divider value programmed by field 7:0 of the - * EDP_BACKLIGHT_FREQ_SET register (DPCD Address 00728h) - * - Where P = 2^Pn, where Pn is the value programmed by field 4:0 of the - * EDP_PWMGEN_BIT_COUNT register (DPCD Address 00724h) - */ -static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connector) -{ - struct drm_i915_private *i915 = to_i915(connector->base.dev); - struct intel_dp *intel_dp = intel_attached_dp(connector); + struct intel_connector *connector = to_intel_connector(old_conn_state->connector); struct intel_panel *panel = &connector->panel; - u32 max_backlight = 0; - int ret, freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; - u8 pn, pn_min, pn_max; - - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap: %d\n", ret); - return 0; - } - - pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - max_backlight = (1 << pn) - 1; - - /* Find desired value of (F x P) - * Note that, if F x P is out of supported range, the maximum value or - * minimum value will applied automatically. So no need to check that. - */ - freq = i915->vbt.backlight.pwm_freq_hz; - drm_dbg_kms(&i915->drm, "VBT defined backlight frequency %u Hz\n", - freq); - if (!freq) { - drm_dbg_kms(&i915->drm, - "Use panel default backlight frequency\n"); - return max_backlight; - } - - fxp = DIV_ROUND_CLOSEST(KHz(DP_EDP_BACKLIGHT_FREQ_BASE_KHZ), freq); - - /* Use highest possible value of Pn for more granularity of brightness - * adjustment while satifying the conditions below. - * - Pn is in the range of Pn_min and Pn_max - * - F is in the range of 1 and 255 - * - FxP is within 25% of desired value. - * Note: 25% is arbitrary value and may need some tweak. - */ - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &pn_min); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap min: %d\n", ret); - return max_backlight; - } - ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX, &pn_max); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap max: %d\n", ret); - return max_backlight; - } - pn_min &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - pn_max &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - - /* Ensure frequency is within 25% of desired value */ - fxp_min = DIV_ROUND_CLOSEST(fxp * 3, 4); - fxp_max = DIV_ROUND_CLOSEST(fxp * 5, 4); - - if (fxp_min < (1 << pn_min) || (255 << pn_max) < fxp_max) { - drm_dbg_kms(&i915->drm, - "VBT defined backlight frequency out of range\n"); - return max_backlight; - } - - for (pn = pn_max; pn >= pn_min; pn--) { - f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); - fxp_actual = f << pn; - if (fxp_min <= fxp_actual && fxp_actual <= fxp_max) - break; - } - - drm_dbg_kms(&i915->drm, "Using eDP pwmgen bit count of %d\n", pn); - ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, pn); - if (ret != 1) { - drm_dbg_kms(&i915->drm, "Failed to write aux pwmgen bit count: %d\n", ret); - return max_backlight; - } - - panel->backlight.edp.vesa.pwmgen_bit_count = pn; - if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_FREQ_AUX_SET_CAP) - panel->backlight.edp.vesa.pwm_freq_pre_divider = f; - - max_backlight = (1 << pn) - 1; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); - return max_backlight; + drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info); } -static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, - enum pipe pipe) +static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, enum pipe pipe) { struct intel_dp *intel_dp = intel_attached_dp(connector); struct intel_panel *panel = &connector->panel; + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + u16 current_level; + u8 current_mode; + int ret; - if (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) - panel->backlight.edp.vesa.aux_enable = true; - if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) - panel->backlight.edp.vesa.lsb_reg_used = true; - - panel->backlight.max = intel_dp_aux_vesa_calc_max_backlight(connector); - if (!panel->backlight.max) - return -ENODEV; + ret = drm_edp_backlight_init(&intel_dp->aux, &panel->backlight.edp.vesa.info, + i915->vbt.backlight.pwm_freq_hz, intel_dp->edp_dpcd, + ¤t_level, ¤t_mode); + if (ret < 0) + return ret; + panel->backlight.max = panel->backlight.edp.vesa.info.max; panel->backlight.min = 0; - panel->backlight.level = intel_dp_aux_vesa_get_backlight(connector, pipe); - panel->backlight.enabled = intel_dp_aux_vesa_backlight_dpcd_mode(connector) && - panel->backlight.level != 0; + if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { + panel->backlight.level = current_level; + panel->backlight.enabled = panel->backlight.level != 0; + } else { + panel->backlight.level = panel->backlight.max; + panel->backlight.enabled = false; + } return 0; } @@ -559,16 +340,12 @@ intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector) struct intel_dp *intel_dp = intel_attached_dp(connector); struct drm_i915_private *i915 = dp_to_i915(intel_dp); - /* Check the eDP Display control capabilities registers to determine if - * the panel can support backlight control over the aux channel. - * - * TODO: We currently only support AUX only backlight configurations, not backlights which + /* TODO: We currently only support AUX only backlight configurations, not backlights which * require a mix of PWM and AUX controls to work. In the mean time, these machines typically * work just fine using normal PWM controls anyway. */ - if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP && - (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) && - (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)) { + if ((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) && + drm_edp_backlight_supported(intel_dp->edp_dpcd)) { drm_dbg_kms(&i915->drm, "AUX Backlight Control Supported!\n"); return true; } diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 06681bf46d81..0bd6396648b4 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1801,6 +1801,24 @@ drm_dp_sink_can_do_video_without_timing_msa(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) DP_MSA_TIMING_PAR_IGNORED; } +/** + * drm_edp_backlight_supported() - Check an eDP DPCD for VESA backlight support + * @edp_dpcd: The DPCD to check + * + * Note that currently this function will return %false for panels which support various DPCD + * backlight features but which require the brightness be set through PWM, and don't support setting + * the brightness level via the DPCD. This is a TODO. + * + * Returns: %True if @edp_dpcd indicates that VESA backlight controls are supported, %false + * otherwise + */ +static inline bool +drm_edp_backlight_supported(const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]) +{ + return (edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP) && + (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP); +} + /* * DisplayPort AUX channel */ @@ -2107,6 +2125,36 @@ drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk) return desc->quirks & BIT(quirk); } +/** + * struct drm_edp_backlight_info - Probed eDP backlight info struct + * @pwmgen_bit_count: The pwmgen bit count + * @pwm_freq_pre_divider: The PWM frequency pre-divider value being used for this backlight, if any + * @max: The maximum backlight level that may be set + * @lsb_reg_used: Do we also write values to the DP_EDP_BACKLIGHT_BRIGHTNESS_LSB register? + * @aux_enable: Does the panel support the AUX enable cap? + * + * This structure contains various data about an eDP backlight, which can be populated by using + * drm_edp_backlight_init(). + */ +struct drm_edp_backlight_info { + u8 pwmgen_bit_count; + u8 pwm_freq_pre_divider; + u16 max; + + bool lsb_reg_used : 1; + bool aux_enable : 1; +}; + +int +drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE], + u16 *current_level, u8 *current_mode); +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level); +int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level); +int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl); + #ifdef CONFIG_DRM_DP_CEC void drm_dp_cec_irq(struct drm_dp_aux *aux); void drm_dp_cec_register_connector(struct drm_dp_aux *aux, |