From: Lothar Wassmann <LW@xxxxxxxxxxxxxxxxxxx> Change the pwm chip driver registration, so that a chip driver that supports polarity inversion can still be used with DTBs that don't provide the 'PWM_POLARITY' flag. This is done to provide polarity inversion support for the pwm-imx driver without having to modify all existing DTS files. Signed-off-by: Lothar Wassmann <LW@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv@xxxxxxxxxxx> Suggested-by: Thierry Reding <thierry.reding@xxxxxxxxx> --- drivers/pwm/core.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 195373e..aae8db3 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -137,9 +137,14 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) { struct pwm_device *pwm; + /* check, whether the driver supports a third cell for flags */ if (pc->of_pwm_n_cells < 3) return ERR_PTR(-EINVAL); + /* flags in the third cell are optional */ + if (args->args_count < 2) + return ERR_PTR(-EINVAL); + if (args->args[0] >= pc->npwm) return ERR_PTR(-EINVAL); @@ -149,10 +154,12 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) pwm->args.period = args->args[1]; - if (args->args[2] & PWM_POLARITY_INVERTED) - pwm->args.polarity = PWM_POLARITY_INVERSED; - else - pwm->args.polarity = PWM_POLARITY_NORMAL; + if (args->args_count > 2) { + if (args->args[2] & PWM_POLARITY_INVERTED) + pwm_set_polarity(pwm, PWM_POLARITY_INVERSED); + else + pwm_set_polarity(pwm, PWM_POLARITY_NORMAL); + } return pwm; } @@ -163,9 +170,14 @@ of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) { struct pwm_device *pwm; + /* sanity check driver support */ if (pc->of_pwm_n_cells < 2) return ERR_PTR(-EINVAL); + /* all cells are required */ + if (args->args_count != pc->of_pwm_n_cells) + return ERR_PTR(-EINVAL); + if (args->args[0] >= pc->npwm) return ERR_PTR(-EINVAL); @@ -672,13 +684,6 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) goto put; } - if (args.args_count != pc->of_pwm_n_cells) { - pr_debug("%s: wrong #pwm-cells for %s\n", np->full_name, - args.np->full_name); - pwm = ERR_PTR(-EINVAL); - goto put; - } - pwm = pc->of_xlate(pc, &args); if (IS_ERR(pwm)) goto put; -- 2.9.2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html