From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: From: Sachin Kamat Subject: [PATCH 1/1] pwm: samsung: Fix kernel warning while unexporting a channel Date: Tue, 29 Oct 2013 10:27:43 +0530 Message-Id: <1383022663-22315-1-git-send-email-sachin.kamat@linaro.org> List-ID: To: linux-pwm@vger.kernel.org Cc: linux-samsung-soc@vger.kernel.org, thierry.reding@gmail.com, tomasz.figa@gmail.com, sachin.kamat@linaro.org PWM channel data was set to NULL before freeing it. This caused the following kernel warning while unexporting the channel. Set the channel data to NULL after freeing it. [ 70.495000] WARNING: CPU: 0 PID: 1 at drivers/base/devres.c:805 pwm_put+0x48/0x80() [ 70.505000] Modules linked in: [ 70.505000] CPU: 0 PID: 1 Comm: sh Not tainted 3.12.0-rc6-next-20131024-00012-gd4aec04-dirty #58 [ 70.515000] [] (unwind_backtrace+0x0/0xf4) from [] (show_stack+0x10/0x14) [ 70.525000] [] (show_stack+0x10/0x14) from [] (dump_stack+0x7c/0xb0) [ 70.530000] [] (dump_stack+0x7c/0xb0) from [] (warn_slowpath_common+0x6c/0x88) [ 70.540000] [] (warn_slowpath_common+0x6c/0x88) from [] (warn_slowpath_null+0x1c/0x24) [ 70.550000] [] (warn_slowpath_null+0x1c/0x24) from [] (pwm_put+0x48/0x80) [ 70.560000] [] (pwm_put+0x48/0x80) from [] (pwm_unexport_store+0x94/0xac) [ 70.565000] [] (pwm_unexport_store+0x94/0xac) from [] (sysfs_write_file+0x148/0x1d8) [ 70.575000] [] (sysfs_write_file+0x148/0x1d8) from [] (vfs_write+0xb4/0x1a0) [ 70.585000] [] (vfs_write+0xb4/0x1a0) from [] (SyS_write+0x3c/0x78) [ 70.595000] [] (SyS_write+0x3c/0x78) from [] (ret_fast_syscall+0x0/0x30) Signed-off-by: Sachin Kamat --- drivers/pwm/pwm-samsung.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c index b2c54c8..6d23eb3 100644 --- a/drivers/pwm/pwm-samsung.c +++ b/drivers/pwm/pwm-samsung.c @@ -226,8 +226,8 @@ static int pwm_samsung_request(struct pwm_chip *chip, struct pwm_device *pwm) static void pwm_samsung_free(struct pwm_chip *chip, struct pwm_device *pwm) { - pwm_set_chip_data(pwm, NULL); devm_kfree(chip->dev, pwm_get_chip_data(pwm)); + pwm_set_chip_data(pwm, NULL); } static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm) -- 1.7.9.5