summaryrefslogtreecommitdiffstats
path: root/drivers/net/phy/linkmode.c
diff options
context:
space:
mode:
authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/net/phy/linkmode.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/net/phy/linkmode.c')
-rw-r--r--drivers/net/phy/linkmode.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/drivers/net/phy/linkmode.c b/drivers/net/phy/linkmode.c
new file mode 100644
index 000000000..f60560fe3
--- /dev/null
+++ b/drivers/net/phy/linkmode.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <linux/linkmode.h>
+
+/**
+ * linkmode_resolve_pause - resolve the allowable pause modes
+ * @local_adv: local advertisement in ethtool format
+ * @partner_adv: partner advertisement in ethtool format
+ * @tx_pause: pointer to bool to indicate whether transmit pause should be
+ * enabled.
+ * @rx_pause: pointer to bool to indicate whether receive pause should be
+ * enabled.
+ *
+ * Flow control is resolved according to our and the link partners
+ * advertisements using the following drawn from the 802.3 specs:
+ * Local device Link partner
+ * Pause AsymDir Pause AsymDir Result
+ * 0 X 0 X Disabled
+ * 0 1 1 0 Disabled
+ * 0 1 1 1 TX
+ * 1 0 0 X Disabled
+ * 1 X 1 X TX+RX
+ * 1 1 0 1 RX
+ */
+void linkmode_resolve_pause(const unsigned long *local_adv,
+ const unsigned long *partner_adv,
+ bool *tx_pause, bool *rx_pause)
+{
+ __ETHTOOL_DECLARE_LINK_MODE_MASK(m);
+
+ linkmode_and(m, local_adv, partner_adv);
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, m)) {
+ *tx_pause = true;
+ *rx_pause = true;
+ } else if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, m)) {
+ *tx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+ partner_adv);
+ *rx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+ local_adv);
+ } else {
+ *tx_pause = false;
+ *rx_pause = false;
+ }
+}
+EXPORT_SYMBOL_GPL(linkmode_resolve_pause);
+
+/**
+ * linkmode_set_pause - set the pause mode advertisement
+ * @advertisement: advertisement in ethtool format
+ * @tx: boolean from ethtool struct ethtool_pauseparam tx_pause member
+ * @rx: boolean from ethtool struct ethtool_pauseparam rx_pause member
+ *
+ * Configure the advertised Pause and Asym_Pause bits according to the
+ * capabilities of provided in @tx and @rx.
+ *
+ * We convert as follows:
+ * tx rx Pause AsymDir
+ * 0 0 0 0
+ * 0 1 1 1
+ * 1 0 0 1
+ * 1 1 1 0
+ *
+ * Note: this translation from ethtool tx/rx notation to the advertisement
+ * is actually very problematical. Here are some examples:
+ *
+ * For tx=0 rx=1, meaning transmit is unsupported, receive is supported:
+ *
+ * Local device Link partner
+ * Pause AsymDir Pause AsymDir Result
+ * 1 1 1 0 TX + RX - but we have no TX support.
+ * 1 1 0 1 Only this gives RX only
+ *
+ * For tx=1 rx=1, meaning we have the capability to transmit and receive
+ * pause frames:
+ *
+ * Local device Link partner
+ * Pause AsymDir Pause AsymDir Result
+ * 1 0 0 1 Disabled - but since we do support tx and rx,
+ * this should resolve to RX only.
+ *
+ * Hence, asking for:
+ * rx=1 tx=0 gives Pause+AsymDir advertisement, but we may end up
+ * resolving to tx+rx pause or only rx pause depending on
+ * the partners advertisement.
+ * rx=0 tx=1 gives AsymDir only, which will only give tx pause if
+ * the partners advertisement allows it.
+ * rx=1 tx=1 gives Pause only, which will only allow tx+rx pause
+ * if the other end also advertises Pause.
+ */
+void linkmode_set_pause(unsigned long *advertisement, bool tx, bool rx)
+{
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT, advertisement, rx);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, advertisement,
+ rx ^ tx);
+}
+EXPORT_SYMBOL_GPL(linkmode_set_pause);