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path: root/drivers/gpu/drm/drm_dp_helper.c
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Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
-rw-r--r--drivers/gpu/drm/drm_dp_helper.c177
1 files changed, 36 insertions, 141 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index ffc68d305afe..2c7870aef469 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -120,33 +120,49 @@ u8 drm_dp_get_adjust_request_pre_emphasis(const u8 link_status[DP_LINK_STATUS_SI
}
EXPORT_SYMBOL(drm_dp_get_adjust_request_pre_emphasis);
-void drm_dp_link_train_clock_recovery_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) {
- int rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
- DP_TRAINING_AUX_RD_MASK;
+u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_LINK_STATUS_SIZE],
+ unsigned int lane)
+{
+ unsigned int offset = DP_ADJUST_REQUEST_POST_CURSOR2;
+ u8 value = dp_link_status(link_status, offset);
+
+ return (value >> (lane << 1)) & 0x3;
+}
+EXPORT_SYMBOL(drm_dp_get_adjust_request_post_cursor);
+
+void drm_dp_link_train_clock_recovery_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
+{
+ unsigned long rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
+ DP_TRAINING_AUX_RD_MASK;
if (rd_interval > 4)
- DRM_DEBUG_KMS("AUX interval %d, out of range (max 4)\n",
+ DRM_DEBUG_KMS("AUX interval %lu, out of range (max 4)\n",
rd_interval);
if (rd_interval == 0 || dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14)
- udelay(100);
+ rd_interval = 100;
else
- mdelay(rd_interval * 4);
+ rd_interval *= 4 * USEC_PER_MSEC;
+
+ usleep_range(rd_interval, rd_interval * 2);
}
EXPORT_SYMBOL(drm_dp_link_train_clock_recovery_delay);
-void drm_dp_link_train_channel_eq_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) {
- int rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
- DP_TRAINING_AUX_RD_MASK;
+void drm_dp_link_train_channel_eq_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
+{
+ unsigned long rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
+ DP_TRAINING_AUX_RD_MASK;
if (rd_interval > 4)
- DRM_DEBUG_KMS("AUX interval %d, out of range (max 4)\n",
+ DRM_DEBUG_KMS("AUX interval %lu, out of range (max 4)\n",
rd_interval);
if (rd_interval == 0)
- udelay(400);
+ rd_interval = 400;
else
- mdelay(rd_interval * 4);
+ rd_interval *= 4 * USEC_PER_MSEC;
+
+ usleep_range(rd_interval, rd_interval * 2);
}
EXPORT_SYMBOL(drm_dp_link_train_channel_eq_delay);
@@ -220,7 +236,6 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
}
ret = aux->transfer(aux, &msg);
-
if (ret >= 0) {
native_reply = msg.reply & DP_AUX_NATIVE_REPLY_MASK;
if (native_reply == DP_AUX_NATIVE_REPLY_ACK) {
@@ -337,134 +352,6 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
EXPORT_SYMBOL(drm_dp_dpcd_read_link_status);
/**
- * drm_dp_link_probe() - probe a DisplayPort link for capabilities
- * @aux: DisplayPort AUX channel
- * @link: pointer to structure in which to return link capabilities
- *
- * The structure filled in by this function can usually be passed directly
- * into drm_dp_link_power_up() and drm_dp_link_configure() to power up and
- * configure the link based on the link's capabilities.
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 values[3];
- int err;
-
- memset(link, 0, sizeof(*link));
-
- err = drm_dp_dpcd_read(aux, DP_DPCD_REV, values, sizeof(values));
- if (err < 0)
- return err;
-
- link->revision = values[0];
- link->rate = drm_dp_bw_code_to_link_rate(values[1]);
- link->num_lanes = values[2] & DP_MAX_LANE_COUNT_MASK;
-
- if (values[2] & DP_ENHANCED_FRAME_CAP)
- link->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
-
- return 0;
-}
-EXPORT_SYMBOL(drm_dp_link_probe);
-
-/**
- * drm_dp_link_power_up() - power up a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 value;
- int err;
-
- /* DP_SET_POWER register is only available on DPCD v1.1 and later */
- if (link->revision < 0x11)
- return 0;
-
- err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
- if (err < 0)
- return err;
-
- value &= ~DP_SET_POWER_MASK;
- value |= DP_SET_POWER_D0;
-
- err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
- if (err < 0)
- return err;
-
- /*
- * According to the DP 1.1 specification, a "Sink Device must exit the
- * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
- * Control Field" (register 0x600).
- */
- usleep_range(1000, 2000);
-
- return 0;
-}
-EXPORT_SYMBOL(drm_dp_link_power_up);
-
-/**
- * drm_dp_link_power_down() - power down a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 value;
- int err;
-
- /* DP_SET_POWER register is only available on DPCD v1.1 and later */
- if (link->revision < 0x11)
- return 0;
-
- err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
- if (err < 0)
- return err;
-
- value &= ~DP_SET_POWER_MASK;
- value |= DP_SET_POWER_D3;
-
- err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
- if (err < 0)
- return err;
-
- return 0;
-}
-EXPORT_SYMBOL(drm_dp_link_power_down);
-
-/**
- * drm_dp_link_configure() - configure a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 values[2];
- int err;
-
- values[0] = drm_dp_link_rate_to_bw_code(link->rate);
- values[1] = link->num_lanes;
-
- if (link->capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
- values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
-
- err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
- if (err < 0)
- return err;
-
- return 0;
-}
-EXPORT_SYMBOL(drm_dp_link_configure);
-
-/**
* drm_dp_downstream_max_clock() - extract branch device max
* pixel rate for legacy VGA
* converter or max TMDS clock
@@ -1109,6 +996,14 @@ EXPORT_SYMBOL(drm_dp_aux_init);
* @aux: DisplayPort AUX channel
*
* Automatically calls drm_dp_aux_init() if this hasn't been done yet.
+ * This should only be called when the underlying &struct drm_connector is
+ * initialiazed already. Therefore the best place to call this is from
+ * &drm_connector_funcs.late_register. Not that drivers which don't follow this
+ * will Oops when CONFIG_DRM_DP_AUX_CHARDEV is enabled.
+ *
+ * Drivers which need to use the aux channel before that point (e.g. at driver
+ * load time, before drm_dev_register() has been called) need to call
+ * drm_dp_aux_init().
*
* Returns 0 on success or a negative error code on failure.
*/
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.