sata: ahci-da850: get the sata clock using a connection id

In preparation for using two clocks in the driver (the sysclk2-based
clock and the external REFCLK), check if we got the 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>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c
index 267a3d3..e397bab 100644 (file)
--- 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 functional clock. This SATA controller
+        * uses two clocks for which we specify two connection ids. If we don't
+        * have the functional clock at this point - call clk_get() again with
+        * con_id = "fck".
+        */
+       if (!hpriv->clks[0]) {
+               clk = clk_get(dev, "fck");
+               if (IS_ERR(clk))
+                       return PTR_ERR(clk);
+
+               hpriv->clks[0] = clk;
+       }
+
        rc = ahci_platform_enable_resources(hpriv);
        if (rc)
                return rc;