phy: cadence-torrent: add suspend and resume support

Add suspend and resume support.

The already_configured flag is cleared during the suspend stage to force
the PHY initialization during the resume stage.

Co-developed-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
Link: https://lore.kernel.org/r/20240412-j7200-phy-s2r-v1-8-f15815833974@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: thom24

drivers/phy/cadence/phy-cadence-torrent.c

@@ -3095,6 +3095,62 @@ static struct cdns_torrent_vals sgmii_qsgmii_xcvr_diag_ln_vals = {
 	.num_regs = ARRAY_SIZE(sgmii_qsgmii_xcvr_diag_ln_regs),
 };
 
+static int cdns_torrent_phy_suspend_noirq(struct device *dev)
+{
+	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
+	int i;
+
+	reset_control_assert(cdns_phy->phy_rst);
+	reset_control_assert(cdns_phy->apb_rst);
+	for (i = 0; i < cdns_phy->nsubnodes; i++)
+		reset_control_assert(cdns_phy->phys[i].lnk_rst);
+
+	if (cdns_phy->already_configured)
+		cdns_phy->already_configured = 0;
+	else {
+		clk_disable_unprepare(cdns_phy->clk1);
+		clk_disable_unprepare(cdns_phy->clk);
+	}
+
+	return 0;
+}
+
+static int cdns_torrent_phy_resume_noirq(struct device *dev)
+{
+	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
+	int node = cdns_phy->nsubnodes;
+	int ret, i;
+
+	ret = cdns_torrent_clk(cdns_phy);
+	if (ret)
+		return ret;
+
+	/* Enable APB */
+	reset_control_deassert(cdns_phy->apb_rst);
+
+	if (cdns_phy->nsubnodes > 1) {
+		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
+		if (ret)
+			goto put_lnk_rst;
+	}
+
+	return 0;
+
+put_lnk_rst:
+	for (i = 0; i < node; i++)
+		reset_control_assert(cdns_phy->phys[i].lnk_rst);
+	reset_control_assert(cdns_phy->apb_rst);
+
+	clk_disable_unprepare(cdns_phy->clk1);
+	clk_disable_unprepare(cdns_phy->clk);
+
+	return ret;
+}
+
+static DEFINE_NOIRQ_DEV_PM_OPS(cdns_torrent_phy_pm_ops,
+			       cdns_torrent_phy_suspend_noirq,
+			       cdns_torrent_phy_resume_noirq);
+
 /* USB and DP link configuration */
 static struct cdns_reg_pairs usb_dp_link_cmn_regs[] = {
 	{0x0002, PHY_PLL_CFG},
@@ -5332,6 +5388,7 @@ static struct platform_driver cdns_torrent_phy_driver = {
 	.driver = {
 		.name	= "cdns-torrent-phy",
 		.of_match_table	= cdns_torrent_phy_of_match,
+		.pm	= pm_sleep_ptr(&cdns_torrent_phy_pm_ops),
 	}
 };
 module_platform_driver(cdns_torrent_phy_driver);