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From:   Claudiu <claudiu.beznea@tuxon.dev>
To:     s.shtylyov@omp.ru, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, p.zabel@pengutronix.de,
        yoshihiro.shimoda.uh@renesas.com, geert+renesas@glider.be,
        wsa+renesas@sang-engineering.com, biju.das.jz@bp.renesas.com,
        prabhakar.mahadev-lad.rj@bp.renesas.com,
        sergei.shtylyov@cogentembedded.com,
        mitsuhiro.kimura.kc@renesas.com, masaru.nagai.vx@renesas.com
Cc:     netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Subject: [PATCH 07/13] net: ravb: Rely on PM domain to enable gptp_clk
Date:   Mon, 20 Nov 2023 10:46:00 +0200
Message-Id: <20231120084606.4083194-8-claudiu.beznea.uj@bp.renesas.com>
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From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

ravb_rzv2m_hw_info::gptp_ref_clk is enabled only for RZ/V2M. RZ/V2M
is an ARM64 based device which selects power domains by default and
CONFIG_PM. The RZ/V2M Ethernet DT node has proper power-domain binding
available in device tree from the commit that added the Ethernet node.
(4872ca1f92b0 ("arm64: dts: renesas: r9a09g011: Add ethernet nodes")).

Power domain support was available in rzg2l-cpg.c driver when the
Ethernet DT node has been enabled in RZ/V2M device tree.
(ef3c613ccd68 ("clk: renesas: Add CPG core wrapper for RZ/G2L SoC")).

Thus remove the explicit clock enable for gptp_clk (and treat it as the
other clocks are treated) as it is not needed and removing it doesn't
break the ABI according to the above explanations.

By removing the enable/disable operation from the driver we can add
runtime PM support (which operates on clocks) w/o the need to handle
the gptp_clk in Ethernet driver functions like ravb_runtime_nop().
PM domain does all that is needed.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---
 drivers/net/ethernet/renesas/ravb_main.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 0fc9810c5e78..836fdb4b3bfd 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2762,7 +2762,6 @@ static int ravb_probe(struct platform_device *pdev)
 			error = PTR_ERR(priv->gptp_clk);
 			goto out_disable_refclk;
 		}
-		clk_prepare_enable(priv->gptp_clk);
 	}
 
 	ndev->max_mtu = info->rx_max_buf_size - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
@@ -2786,7 +2785,7 @@ static int ravb_probe(struct platform_device *pdev)
 		/* Set GTI value */
 		error = ravb_set_gti(ndev);
 		if (error)
-			goto out_disable_gptp_clk;
+			goto out_disable_refclk;
 
 		/* Request GTI loading */
 		ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
@@ -2806,7 +2805,7 @@ static int ravb_probe(struct platform_device *pdev)
 			"Cannot allocate desc base address table (size %d bytes)\n",
 			priv->desc_bat_size);
 		error = -ENOMEM;
-		goto out_disable_gptp_clk;
+		goto out_disable_refclk;
 	}
 	for (q = RAVB_BE; q < DBAT_ENTRY_NUM; q++)
 		priv->desc_bat[q].die_dt = DT_EOS;
@@ -2869,8 +2868,6 @@ static int ravb_probe(struct platform_device *pdev)
 	/* Stop PTP Clock driver */
 	if (info->ccc_gac)
 		ravb_ptp_stop(ndev);
-out_disable_gptp_clk:
-	clk_disable_unprepare(priv->gptp_clk);
 out_disable_refclk:
 	clk_disable_unprepare(priv->refclk);
 out_release:
@@ -2893,7 +2890,6 @@ static void ravb_remove(struct platform_device *pdev)
 	if (info->ccc_gac)
 		ravb_ptp_stop(ndev);
 
-	clk_disable_unprepare(priv->gptp_clk);
 	clk_disable_unprepare(priv->refclk);
 
 	/* Set reset mode */
-- 
2.39.2