From 394b99f37dd199599e383024dc40aa84eec6de3e Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 17 May 2016 14:27:25 +0200 Subject: [PATCH] UPSTREAM: pwm: Fix pwm_apply_args() call sites pwm_apply_args() is supposed to initialize a PWM device according to the arguments provided by the DT or the PWM lookup, but this function was called inside pwm_device_request(), which in turn was called before the core had a chance to initialize the pwm->args fields. Fix that by calling pwm_apply_args directly in pwm_get() and of_pwm_get() after initializing pwm->args field. This commit also fixes an invalid pointer dereference introduced by commit e39c0df1be5a ("pwm: Introduce the pwm_args concept"). Signed-off-by: Boris Brezillon Fixes: e39c0df1be5a ("pwm: Introduce the pwm_args concept") Signed-off-by: Thierry Reding (cherry picked from commit fbd45a12988e75a48d392feb8b0e5feb5d612513) Change-Id: I9746f4ada57a6cc8155bafe662a63c82338c223a Signed-off-by: David Wu --- drivers/pwm/core.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 8fbd7c5d34b6..7bb31429886e 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -129,13 +129,6 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label) set_bit(PWMF_REQUESTED, &pwm->flags); pwm->label = label; - /* - * FIXME: This should be removed once all PWM users properly make use - * of struct pwm_args to initialize the PWM device. As long as this is - * here, the PWM state and hardware state can get out of sync. - */ - pwm_apply_args(pwm); - return 0; } @@ -630,6 +623,13 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) pwm->label = con_id; + /* + * FIXME: This should be removed once all PWM users properly make use + * of struct pwm_args to initialize the PWM device. As long as this is + * here, the PWM state and hardware state can get out of sync. + */ + pwm_apply_args(pwm); + put: of_node_put(args.np); @@ -757,13 +757,20 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) if (!chip) goto out; - pwm->args.period = chosen->period; - pwm->args.polarity = chosen->polarity; - pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id); if (IS_ERR(pwm)) goto out; + pwm->args.period = chosen->period; + pwm->args.polarity = chosen->polarity; + + /* + * FIXME: This should be removed once all PWM users properly make use + * of struct pwm_args to initialize the PWM device. As long as this is + * here, the PWM state and hardware state can get out of sync. + */ + pwm_apply_args(pwm); + out: mutex_unlock(&pwm_lookup_lock); return pwm; -- 2.34.1