[PATCH v4 15/17] pwm: sti: It's now valid for number of PWM channels to be zero
From: Lee Jones <hidden>
Date: 2016-08-16 09:36:44
Also in:
linux-devicetree, linux-pwm, lkml
Subsystem:
pwm subsystem, the rest · Maintainers:
Uwe Kleine-König, Linus Torvalds
Setting up the STI PWM IP as capture only, with zero PWM-out devices is a perfectly valued configuration. It is no longer okay to assume that there must be at least 1 PWM-out devices. In this patch we make the default number of PWM-out devices zero and only configure channels explicitly requested. Reported-by: Peter Griffin <peter.griffin@linaro.org> Signed-off-by: Lee Jones <redacted> --- drivers/pwm/pwm-sti.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c
index fcc80eb..a1319c0 100644
--- a/drivers/pwm/pwm-sti.c
+++ b/drivers/pwm/pwm-sti.c@@ -483,6 +483,11 @@ static int sti_pwm_probe_dt(struct sti_pwm_chip *pc) if (!ret) cdata->cpt_num_devs = num_devs; + if (cdata->pwm_num_devs && !cdata->cpt_num_devs) { + dev_err(dev, "No channels configured\n"); + return -EINVAL; + } + reg_fields = cdata->reg_fields; pc->prescale_low = devm_regmap_field_alloc(dev, pc->regmap,
@@ -573,7 +578,7 @@ static int sti_pwm_probe(struct platform_device *pdev) cdata->reg_fields = &sti_pwm_regfields[0]; cdata->max_prescale = 0xff; cdata->max_pwm_cnt = 255; - cdata->pwm_num_devs = 1; + cdata->pwm_num_devs = 0; cdata->cpt_num_devs = 0; pc->cdata = cdata;
@@ -585,6 +590,9 @@ static int sti_pwm_probe(struct platform_device *pdev) if (ret) return ret; + if (!cdata->pwm_num_devs) + goto skip_pwm; + pc->pwm_clk = of_clk_get_by_name(dev->of_node, "pwm"); if (IS_ERR(pc->pwm_clk)) { dev_err(dev, "failed to get PWM clock\n");
@@ -597,6 +605,10 @@ static int sti_pwm_probe(struct platform_device *pdev) return ret; } +skip_pwm: + if (!cdata->cpt_num_devs) + goto skip_cpt; + pc->cpt_clk = of_clk_get_by_name(dev->of_node, "capture"); if (IS_ERR(pc->cpt_clk)) { dev_err(dev, "failed to get PWM capture clock\n");
@@ -609,6 +621,7 @@ static int sti_pwm_probe(struct platform_device *pdev) return ret; } +skip_cpt: pc->chip.dev = dev; pc->chip.ops = &sti_pwm_ops; pc->chip.base = -1;
--
2.9.0