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.grif...@linaro.org>
Signed-off-by: Lee Jones <lee.jo...@linaro.org>
---
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 cecb6d4..64db5a5 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;
--
2.8.3
