[PATCHv4 04/15] ov7670: get xclk

[Hans Verkuil]

From: Hans Verkuil <hans.verk...@cisco.com>

Get the clock for this sensor.

Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
---
 drivers/media/i2c/ov7670.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
index 50e4466a2b37..912ff09c6100 100644
--- a/drivers/media/i2c/ov7670.c
+++ b/drivers/media/i2c/ov7670.c
@@ -10,6 +10,7 @@
  * This file may be distributed under the terms of the GNU General
  * Public License, version 2.
  */
+#include <linux/clk.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/slab.h>
@@ -227,6 +228,7 @@ struct ov7670_info {
                struct v4l2_ctrl *hue;
        };
        struct ov7670_format_struct *fmt;  /* Current format */
+       struct clk *clk;
        int min_width;                  /* Filter out smaller sizes */
        int min_height;                 /* Filter out smaller sizes */
        int clock_speed;                /* External clock speed (MHz) */
@@ -1587,13 +1589,24 @@ 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 -EPROBE_DEFER;
+       clk_prepare_enable(info->clk);
+
+       info->clock_speed = clk_get_rate(info->clk) / 1000000;
+       if (info->clock_speed < 10 || info->clock_speed > 48) {
+               ret = -EINVAL;
+               goto clk_disable;
+       }
+
        /* Make sure it's an ov7670 */
        ret = ov7670_detect(sd);
        if (ret) {
                v4l_dbg(1, debug, client,
                        "chip found @ 0x%x (%s) is not an ov7670 chip.\n",
                        client->addr << 1, client->adapter->name);
-               return ret;
+               goto clk_disable;
        }
        v4l_info(client, "chip found @ 0x%02x (%s)\n",
                        client->addr << 1, client->adapter->name);
@@ -1656,6 +1669,8 @@ static int ov7670_probe(struct i2c_client *client,
 
 hdl_free:
        v4l2_ctrl_handler_free(&info->hdl);
+clk_disable:
+       clk_disable_unprepare(info->clk);
        return ret;
 }
 
@@ -1667,6 +1682,7 @@ static int ov7670_remove(struct i2c_client *client)
 
        v4l2_device_unregister_subdev(sd);
        v4l2_ctrl_handler_free(&info->hdl);
+       clk_disable_unprepare(info->clk);
        return 0;
 }
 
-- 
2.11.0