media: ov7670: make "xclk" clock optional

commit 786fa584eda86d6598db3b87c61dc81f68808d11 upstream.

When the "xclk" clock was added, it was made mandatory. This broke the
driver on an OLPC plaform which doesn't know such clock. Make it
optional.

Tested on a OLPC XO-1 laptop.

Fixes: 0a024d634cee ("[media] ov7670: get xclk")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
index 3474ef832c1ef1c3bb247e5c6c8ddb2f51250c70..480edeebac60a2da51bfd6abf87e2237dc98cfad 100644 (file)
--- a/drivers/media/i2c/ov7670.c
+++ b/drivers/media/i2c/ov7670.c
@@ -1810,17 +1810,24 @@ static int ov7670_probe(struct i2c_client *client,
                        info->pclk_hb_disable = true;
        }
 
-       info->clk = devm_clk_get(&client->dev, "xclk");
-       if (IS_ERR(info->clk))
-               return PTR_ERR(info->clk);
-       ret = clk_prepare_enable(info->clk);
-       if (ret)
-               return ret;
+       info->clk = devm_clk_get(&client->dev, "xclk"); /* optional */
+       if (IS_ERR(info->clk)) {
+               ret = PTR_ERR(info->clk);
+               if (ret == -ENOENT)
+                       info->clk = NULL;
+               else
+                       return ret;
+       }
+       if (info->clk) {
+               ret = clk_prepare_enable(info->clk);
+               if (ret)
+                       return ret;
 
-       info->clock_speed = clk_get_rate(info->clk) / 1000000;
-       if (info->clock_speed < 10 || info->clock_speed > 48) {
-               ret = -EINVAL;
-               goto clk_disable;
+               info->clock_speed = clk_get_rate(info->clk) / 1000000;
+               if (info->clock_speed < 10 || info->clock_speed > 48) {
+                       ret = -EINVAL;
+                       goto clk_disable;
+               }
        }
 
        ret = ov7670_init_gpio(client, info);