[PATCH 3.10 25/54] iio: lpc32xx_adc: fix warnings caused by enabling unprepared clock

Greg Kroah-Hartman
2016-02-24T04:03:17Z

From: Vladimir Zapolskiy <vz@mleia.com>

commit 01bb70ae0b98d266fa3e860482c7ce22fa482a6e upstream.

If common clock framework is configured, the driver generates a warning,
which is fixed by this change:

root@devkit3250:~# cat /sys/bus/iio/devices/iio\:device0/in_voltage0_raw
------------[ cut here ]------------
WARNING: CPU: 0 PID: 724 at drivers/clk/clk.c:727 clk_core_enable+0x2c/0xa4()
Modules linked in: sc16is7xx snd_soc_uda1380
CPU: 0 PID: 724 Comm: cat Not tainted 4.3.0-rc2+ #198
Hardware name: LPC32XX SoC (Flattened Device Tree)
Backtrace:
[<>] (dump_backtrace) from [<>] (show_stack+0x18/0x1c)
[<>] (show_stack) from [<>] (dump_stack+0x20/0x28)
[<>] (dump_stack) from [<>] (warn_slowpath_common+0x90/0xb8)
[<>] (warn_slowpath_common) from [<>] (warn_slowpath_null+0x24/0x2c)
[<>] (warn_slowpath_null) from [<>] (clk_core_enable+0x2c/0xa4)
[<>] (clk_core_enable) from [<>] (clk_enable+0x24/0x38)
[<>] (clk_enable) from [<>] (lpc32xx_read_raw+0x38/0x80)
[<>] (lpc32xx_read_raw) from [<>] (iio_read_channel_info+0x70/0x94)
[<>] (iio_read_channel_info) from [<>] (dev_attr_show+0x28/0x4c)
[<>] (dev_attr_show) from [<>] (sysfs_kf_seq_show+0x8c/0xf0)
[<>] (sysfs_kf_seq_show) from [<>] (kernfs_seq_show+0x2c/0x30)
[<>] (kernfs_seq_show) from [<>] (seq_read+0x1c8/0x440)
[<>] (seq_read) from [<>] (kernfs_fop_read+0x38/0x170)
[<>] (kernfs_fop_read) from [<>] (do_readv_writev+0x16c/0x238)
[<>] (do_readv_writev) from [<>] (vfs_readv+0x50/0x58)
[<>] (vfs_readv) from [<>] (default_file_splice_read+0x1a4/0x308)
[<>] (default_file_splice_read) from [<>] (do_splice_to+0x78/0x84)
[<>] (do_splice_to) from [<>] (splice_direct_to_actor+0xc8/0x1cc)
[<>] (splice_direct_to_actor) from [<>] (do_splice_direct+0xa0/0xb8)
[<>] (do_splice_direct) from [<>] (do_sendfile+0x1a8/0x30c)
[<>] (do_sendfile) from [<>] (SyS_sendfile64+0x104/0x10c)
[<>] (SyS_sendfile64) from [<>] (ret_fast_syscall+0x0/0x38)

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/staging/iio/adc/lpc32xx_adc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/staging/iio/adc/lpc32xx_adc.c
+++ b/drivers/staging/iio/adc/lpc32xx_adc.c
@@ -76,7 +76,7 @@ static int lpc32xx_read_raw(struct iio_d

if (mask == IIO_CHAN_INFO_RAW) {
mutex_lock(&indio_dev->mlock);
- clk_enable(info->clk);
+ clk_prepare_enable(info->clk);
/* Measurement setup */
__raw_writel(AD_INTERNAL | (chan->address) | AD_REFp | AD_REFm,
LPC32XX_ADC_SELECT(info->adc_base));
@@ -84,7 +84,7 @@ static int lpc32xx_read_raw(struct iio_d
__raw_writel(AD_PDN_CTRL | AD_STROBE,
LPC32XX_ADC_CTRL(info->adc_base));
wait_for_completion(&info->completion); /* set by ISR */
- clk_disable(info->clk);
+ clk_disable_unprepare(info->clk);
*val = info->value;
mutex_unlock(&indio_dev->mlock);