Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1561782

[PATCH v3 04/13] sata: ahci-da850: get the sata clock using a connection id

From Bartosz Golaszewski <bgolaszewski@baylibre.com>
Newsgroups linux.kernel
Subject [PATCH v3 04/13] sata: ahci-da850: get the sata clock using a connection id
Date 2017-01-18 14:30 +0100
Message-ID <t0Ytl-4D1-53@gated-at.bofh.it> (permalink)
References <t0Ytk-4D1-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


In preparation for using two clocks in the driver (the sysclk2-based
clock and the external REFCLK), check if we got a functional clock
after calling ahci_platform_get_resources(). If not, retry calling
clk_get() with con_id specified.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/ata/ahci_da850.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c
index 267a3d3..8cfdc86 100644
--- a/drivers/ata/ahci_da850.c
+++ b/drivers/ata/ahci_da850.c
@@ -71,12 +71,28 @@ static int ahci_da850_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	struct resource *res;
 	void __iomem *pwrdn_reg;
+	struct clk *clk;
 	int rc;
 
 	hpriv = ahci_platform_get_resources(pdev);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
+	/*
+	 * Internally ahci_platform_get_resources() calls clk_get(dev, NULL)
+	 * when trying to obtain the first clock. This SATA controller uses
+	 * two clocks for which we specify two connection ids. If we don't
+	 * have a clock at this point - call clk_get() again with
+	 * con_id = "sata".
+	 */
+	if (!hpriv->clks[0]) {
+		clk = clk_get(dev, "sata");
+		if (IS_ERR(clk))
+			return PTR_ERR(clk);
+
+		hpriv->clks[0] = clk;
+	}
+
 	rc = ahci_platform_enable_resources(hpriv);
 	if (rc)
 		return rc;
-- 
2.9.3

Back to linux.kernel | Previous | Next | Find similar | Unroll thread


Thread

[PATCH v3 04/13] sata: ahci-da850: get the sata clock using a connection id Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2017-01-18 14:30 +0100

csiph-web