[PATCH v3 12/20] pwm: sti: Only request clock rate when you need to
From: Lee Jones <hidden>
Date: 2016-06-08 09:27:26
Also in:
linux-devicetree, linux-pwm, lkml
Subsystem:
pwm subsystem, the rest · Maintainers:
Uwe Kleine-König, Linus Torvalds
In the original code the clock rate was only obtained during initialisation; however, the rate may change between then and its use. This patch ensures the correct rate is acquired just before use. Signed-off-by: Lee Jones <redacted> --- drivers/pwm/pwm-sti.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c
index 5fbee61..c4a34af 100644
--- a/drivers/pwm/pwm-sti.c
+++ b/drivers/pwm/pwm-sti.c@@ -51,7 +51,6 @@ struct sti_pwm_compat_data { struct sti_pwm_chip { struct device *dev; - unsigned long clk_rate; struct clk *pwm_clk; struct regmap *regmap; struct sti_pwm_compat_data *cdata;
@@ -86,13 +85,20 @@ static int sti_pwm_get_prescale(struct sti_pwm_chip *pc, unsigned long period, unsigned int *prescale) { struct sti_pwm_compat_data *cdata = pc->cdata; + unsigned long clk_rate; unsigned long val; unsigned int ps; + clk_rate = clk_get_rate(pc->pwm_clk); + if (!clk_rate) { + dev_err(pc->dev, "failed to get clock rate\n"); + return -EINVAL; + } + /* * prescale = ((period_ns * clk_rate) / (10^9 * (max_pwm_count + 1)) - 1 */ - val = NSEC_PER_SEC / pc->clk_rate; + val = NSEC_PER_SEC / clk_rate; val *= cdata->max_pwm_cnt + 1; if (period % val) {
@@ -353,12 +359,6 @@ static int sti_pwm_probe(struct platform_device *pdev) return PTR_ERR(pc->pwm_clk); } - pc->clk_rate = clk_get_rate(pc->pwm_clk); - if (!pc->clk_rate) { - dev_err(dev, "failed to get clock rate\n"); - return -EINVAL; - } - ret = clk_prepare(pc->pwm_clk); if (ret) { dev_err(dev, "failed to prepare clock\n");
--
2.8.3