From: Michał Mirosław mirq-linux@rere.qmqm.pl
commit b037d60a3b1d1227609fd858fa34321f41829911 upstream.
Uninterruptible context is not needed in the driver and causes lockdep warning because of mutex taken in of_alias_get_id(). Convert the lock to mutex to avoid the issue.
Cc: stable@vger.kernel.org Fixes: 099343c64e16 ("ARM: at91: atmel-ssc: add device tree support") Signed-off-by: Michał Mirosław mirq-linux@rere.qmqm.pl Link: https://lore.kernel.org/r/50f0d7fa107f318296afb49477c3571e4d6978c5.159299840... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/misc/atmel-ssc.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-)
--- a/drivers/misc/atmel-ssc.c +++ b/drivers/misc/atmel-ssc.c @@ -13,7 +13,7 @@ #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> -#include <linux/spinlock.h> +#include <linux/mutex.h> #include <linux/atmel-ssc.h> #include <linux/slab.h> #include <linux/module.h> @@ -21,7 +21,7 @@ #include <linux/of.h>
/* Serialize access to ssc_list and user count */ -static DEFINE_SPINLOCK(user_lock); +static DEFINE_MUTEX(user_lock); static LIST_HEAD(ssc_list);
struct ssc_device *ssc_request(unsigned int ssc_num) @@ -29,7 +29,7 @@ struct ssc_device *ssc_request(unsigned int ssc_valid = 0; struct ssc_device *ssc;
- spin_lock(&user_lock); + mutex_lock(&user_lock); list_for_each_entry(ssc, &ssc_list, list) { if (ssc->pdev->dev.of_node) { if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc") @@ -44,18 +44,18 @@ struct ssc_device *ssc_request(unsigned }
if (!ssc_valid) { - spin_unlock(&user_lock); + mutex_unlock(&user_lock); pr_err("ssc: ssc%d platform device is missing\n", ssc_num); return ERR_PTR(-ENODEV); }
if (ssc->user) { - spin_unlock(&user_lock); + mutex_unlock(&user_lock); dev_dbg(&ssc->pdev->dev, "module busy\n"); return ERR_PTR(-EBUSY); } ssc->user++; - spin_unlock(&user_lock); + mutex_unlock(&user_lock);
clk_prepare(ssc->clk);
@@ -67,14 +67,14 @@ void ssc_free(struct ssc_device *ssc) { bool disable_clk = true;
- spin_lock(&user_lock); + mutex_lock(&user_lock); if (ssc->user) ssc->user--; else { disable_clk = false; dev_dbg(&ssc->pdev->dev, "device already free\n"); } - spin_unlock(&user_lock); + mutex_unlock(&user_lock);
if (disable_clk) clk_unprepare(ssc->clk); @@ -194,9 +194,9 @@ static int ssc_probe(struct platform_dev return -ENXIO; }
- spin_lock(&user_lock); + mutex_lock(&user_lock); list_add_tail(&ssc->list, &ssc_list); - spin_unlock(&user_lock); + mutex_unlock(&user_lock);
platform_set_drvdata(pdev, ssc);
@@ -210,9 +210,9 @@ static int ssc_remove(struct platform_de { struct ssc_device *ssc = platform_get_drvdata(pdev);
- spin_lock(&user_lock); + mutex_lock(&user_lock); list_del(&ssc->list); - spin_unlock(&user_lock); + mutex_unlock(&user_lock);
return 0; }