From 96d16c3088a924a44175d2923cc0eafa0d8bbecc Mon Sep 17 00:00:00 2001 From: Francesco VIRLINZI Date: Mon, 5 Jan 2015 11:04:13 +0100 Subject: [PATCH] pinctrl: st: avoid multiple mutex lock Using the sysfs inteface to inspect the pins configuration the system can walk around a path which acquires the same mutex twice. On STiH407 platform, for example : cat /sys/kernel/debug/pinctrl/920f080.pin-controller-front0/pinconf-pins hangs the kernel and never returns. With this patch the mutex is temporary freed. Signed-off-by: Francesco Virlinzi Signed-off-by: Patrice Chotard Signed-off-by: Linus Walleij --- drivers/pinctrl/pinctrl-st.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c index 7c9d513..87570e6 100644 --- a/drivers/pinctrl/pinctrl-st.c +++ b/drivers/pinctrl/pinctrl-st.c @@ -1012,8 +1012,10 @@ static void st_pinconf_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s, unsigned pin_id) { unsigned long config; - st_pinconf_get(pctldev, pin_id, &config); + mutex_unlock(&pctldev->mutex); + st_pinconf_get(pctldev, pin_id, &config); + mutex_lock(&pctldev->mutex); seq_printf(s, "[OE:%ld,PU:%ld,OD:%ld]\n" "\t\t[retime:%ld,invclk:%ld,clknotdat:%ld," "de:%ld,rt-clk:%ld,rt-delay:%ld]", -- 2.7.4