i2c: ocores: rework clk code to handle NULL cookie

For, !HAVE_CLK the clk API returns a NULL cookie. Rework the
initialization code to handle that. If clk_get_rate() delivers 0, we use
the fallback mechanisms. The patch is pretty easy when ignoring white
space issues (git diff -b).

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 3fc76b6ffcaadeca54971822aab7ce133ce8dee6..abf5db7e441ebab65fc7c8ad99b5f9bca6218b15 100644 (file)
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -354,20 +354,24 @@ static int ocores_i2c_of_probe(struct platform_device *pdev,
                i2c->ip_clock_khz = clk_get_rate(i2c->clk) / 1000;
                if (clock_frequency_present)
                        i2c->bus_clock_khz = clock_frequency / 1000;
-       } else if (of_property_read_u32(np, "opencores,ip-clock-frequency",
-                                       &val)) {
-               if (!clock_frequency_present) {
-                       dev_err(&pdev->dev,
-                               "Missing required parameter 'opencores,ip-clock-frequency'\n");
-                       return -ENODEV;
+       }
+
+       if (i2c->ip_clock_khz == 0) {
+               if (of_property_read_u32(np, "opencores,ip-clock-frequency",
+                                               &val)) {
+                       if (!clock_frequency_present) {
+                               dev_err(&pdev->dev,
+                                       "Missing required parameter 'opencores,ip-clock-frequency'\n");
+                               return -ENODEV;
+                       }
+                       i2c->ip_clock_khz = clock_frequency / 1000;
+                       dev_warn(&pdev->dev,
+                                "Deprecated usage of the 'clock-frequency' property, please update to 'opencores,ip-clock-frequency'\n");
+               } else {
+                       i2c->ip_clock_khz = val / 1000;
+                       if (clock_frequency_present)
+                               i2c->bus_clock_khz = clock_frequency / 1000;
                }
-               i2c->ip_clock_khz = clock_frequency / 1000;
-               dev_warn(&pdev->dev,
-                        "Deprecated usage of the 'clock-frequency' property, please update to 'opencores,ip-clock-frequency'\n");
-       } else {
-               i2c->ip_clock_khz = val / 1000;
-               if (clock_frequency_present)
-                       i2c->bus_clock_khz = clock_frequency / 1000;
        }
 
        of_property_read_u32(pdev->dev.of_node, "reg-io-width",
@@ -518,6 +522,7 @@ static int ocores_i2c_resume(struct device *dev)
        struct ocores_i2c *i2c = dev_get_drvdata(dev);
 
        if (!IS_ERR(i2c->clk)) {
+               unsigned long rate;
                int ret = clk_prepare_enable(i2c->clk);
 
                if (ret) {
@@ -525,7 +530,9 @@ static int ocores_i2c_resume(struct device *dev)
                                "clk_prepare_enable failed: %d\n", ret);
                        return ret;
                }
-               i2c->ip_clock_khz = clk_get_rate(i2c->clk) / 1000;
+               rate = clk_get_rate(i2c->clk) / 1000;
+               if (rate)
+                       i2c->ip_clock_khz = rate;
        }
        return ocores_init(dev, i2c);
 }