iio: ep93xx: Prepare clock before using it

Use clk_prepare_enable()/clk_disable_unprepare() in preparation for switch
to Common Clock Framework, otherwise the following is visible:

WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:1011 clk_core_enable+0x9c/0xbc
Enabling unprepared ep93xx-adc
CPU: 0 PID: 1 Comm: swapper Not tainted 5.13.0-rc5-... #1
Hardware name: Cirrus Logic EDB9302 Evaluation Board
[<c000d5b0>] (unwind_backtrace) from [<c000c590>] (show_stack+0x10/0x18)
[<c000c590>] (show_stack) from [<c03a5f38>] (dump_stack+0x20/0x2c)
[<c03a5f38>] (dump_stack) from [<c03a2098>] (__warn+0x98/0xc0)
[<c03a2098>] (__warn) from [<c03a2150>] (warn_slowpath_fmt+0x90/0xc0)
[<c03a2150>] (warn_slowpath_fmt) from [<c01d8358>] (clk_core_enable+0x9c/0xbc)
[<c01d8358>] (clk_core_enable) from [<c01d8698>] (clk_core_enable_lock+0x18/0x30)
[<c01d8698>] (clk_core_enable_lock) from [<c0266560>] (ep93xx_adc_probe+0xe4/0x1a0)
[<c0266560>] (ep93xx_adc_probe) from [<c02126e0>] (platform_probe+0x34/0x80)
[<c02126e0>] (platform_probe) from [<c0210bf8>] (really_probe+0xe8/0x394)
[<c0210bf8>] (really_probe) from [<c0211464>] (device_driver_attach+0x5c/0x64)
[<c0211464>] (device_driver_attach) from [<c02114e8>] (__driver_attach+0x7c/0xec)
[<c02114e8>] (__driver_attach) from [<c020f1b4>] (bus_for_each_dev+0x78/0xc4)
[<c020f1b4>] (bus_for_each_dev) from [<c0211570>] (driver_attach+0x18/0x24)
[<c0211570>] (driver_attach) from [<c020fab4>] (bus_add_driver+0x140/0x1cc)
[<c020fab4>] (bus_add_driver) from [<c0211c44>] (driver_register+0x74/0x114)
[<c0211c44>] (driver_register) from [<c02134f8>] (__platform_driver_register+0x18/0x24)
[<c02134f8>] (__platform_driver_register) from [<c0470148>] (ep93xx_adc_driver_init+0x10/0x1c)
[<c0470148>] (ep93xx_adc_driver_init) from [<c045ce88>] (do_one_initcall+0x7c/0x1a4)
[<c045ce88>] (do_one_initcall) from [<c045d184>] (kernel_init_freeable+0x17c/0x1fc)
[<c045d184>] (kernel_init_freeable) from [<c03a64d0>] (kernel_init+0x8/0xf8)
[<c03a64d0>] (kernel_init) from [<c00082d8>] (ret_from_fork+0x14/0x3c)
...
ep93xx-adc ep93xx-adc: Cannot enable clock
ep93xx-adc: probe of ep93xx-adc failed with error -108

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Link: https://lore.kernel.org/r/20210613233041.128961-2-alexander.sverdlin@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/ep93xx_adc.c b/drivers/iio/adc/ep93xx_adc.c
index a10a4e8d94fdda8a5bbe522545ae38d6786b78c1..8edd6407b7c34823568eb3b06a1b7488a054943f 100644 (file)
--- a/drivers/iio/adc/ep93xx_adc.c
+++ b/drivers/iio/adc/ep93xx_adc.c
@@ -205,7 +205,7 @@ static int ep93xx_adc_probe(struct platform_device *pdev)
                 */
        }
 
-       ret = clk_enable(priv->clk);
+       ret = clk_prepare_enable(priv->clk);
        if (ret) {
                dev_err(&pdev->dev, "Cannot enable clock\n");
                return ret;
@@ -213,7 +213,7 @@ static int ep93xx_adc_probe(struct platform_device *pdev)
 
        ret = iio_device_register(iiodev);
        if (ret)
-               clk_disable(priv->clk);
+               clk_disable_unprepare(priv->clk);
 
        return ret;
 }
@@ -224,7 +224,7 @@ static int ep93xx_adc_remove(struct platform_device *pdev)
        struct ep93xx_adc_priv *priv = iio_priv(iiodev);
 
        iio_device_unregister(iiodev);
-       clk_disable(priv->clk);
+       clk_disable_unprepare(priv->clk);
 
        return 0;
 }