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* [PATCH] mmc: sdhci-of-arasan: Add support to request the "gate" clock
@ 2023-02-23 14:14 Swati Agarwal
  2023-02-27  8:16 ` Michal Simek
                   ` (3 more replies)
  0 siblings, 4 replies; 7+ messages in thread
From: Swati Agarwal @ 2023-02-23 14:14 UTC (permalink / raw)
  To: adrian.hunter, michal.simek, ulf.hansson
  Cc: linux-mmc, linux-arm-kernel, linux-kernel, git

Add support to read the optional "gate" clock property and request the
clock which will be used to ungate the DLL clock.

For Xilinx platforms which has DLL module, dll clock must be
ungated/enabled when SD controller operates at higher frequencies like 50
MHz, 100 MHz and 200 MHz. This will be done by explicitly requesting gate
clock from the driver.

Signed-off-by: Swati Agarwal <swati.agarwal@amd.com>
---
 drivers/mmc/host/sdhci-of-arasan.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 4eebbf801b41..1fd7528c14fc 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -1870,6 +1870,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 	int ret;
 	struct device_node *node;
 	struct clk *clk_xin;
+	struct clk *clk_dll;
 	struct sdhci_host *host;
 	struct sdhci_pltfm_host *pltfm_host;
 	struct device *dev = &pdev->dev;
@@ -1943,6 +1944,12 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 		goto clk_dis_ahb;
 	}
 
+	clk_dll = devm_clk_get_optional_enabled(dev, "gate");
+	if (IS_ERR(clk_dll)) {
+		ret = dev_err_probe(dev, PTR_ERR(clk_dll), "failed to get dll clk\n");
+		goto clk_disable_all;
+	}
+
 	if (of_property_read_bool(np, "xlnx,fails-without-test-cd"))
 		sdhci_arasan->quirks |= SDHCI_ARASAN_QUIRK_FORCE_CDTEST;
 
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2023-03-09 15:05 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-02-23 14:14 [PATCH] mmc: sdhci-of-arasan: Add support to request the "gate" clock Swati Agarwal
2023-02-27  8:16 ` Michal Simek
2023-02-27 14:56 ` Ulf Hansson
2023-02-27 15:09   ` Michal Simek
2023-02-27 15:31     ` Ulf Hansson
2023-03-02 11:09 ` Adrian Hunter
2023-03-09 15:02 ` Ulf Hansson

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