On 06/22/2017 06:46 PM, Patrick Venture wrote:
The reference driver polled but mentioned it was possible to sleep
for a computed period to know when it's ready to read. However, polling
with minimal sleeps is quick and works. This also improves responsiveness
from the driver.
Testing: tested on ast2400 on quanta-q71l
Signed-off-by: Patrick Venture <venture@xxxxxxxxxx>
---
drivers/hwmon/aspeed-pwm-tacho.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
index b2ab5612d8a4..b865541f4858 100644
--- a/drivers/hwmon/aspeed-pwm-tacho.c
+++ b/drivers/hwmon/aspeed-pwm-tacho.c
@@ -163,6 +163,9 @@
#define M_TACH_UNIT 0x00c0
#define INIT_FAN_CTRL 0xFF
+/* How long we sleep while waiting for an RPM result. */
+#define ASPEED_RPM_STATUS_SLEEP 500
+
Please add units (us ? ms ? HZ ? hours ? days ?)
... for an RPM result, in <unit>
Also please reflect the unit in the define, and use a tab before the number.
I don't see patch 1/2. Still coming ? And didn't we already have a v2 ?
struct aspeed_pwm_tacho_data {
struct regmap *regmap;
unsigned long clk_freq;
@@ -508,7 +511,7 @@ static u32 aspeed_get_fan_tach_ch_measure_period(struct aspeed_pwm_tacho_data
static int aspeed_get_fan_tach_ch_rpm(struct aspeed_pwm_tacho_data *priv,
u8 fan_tach_ch)
{
- u32 raw_data, tach_div, clk_source, sec, val;
+ u32 raw_data, tach_div, clk_source, msec, usec, val;
u8 fan_tach_ch_source, type, mode, both;
regmap_write(priv->regmap, ASPEED_PTCR_TRIGGER, 0);
@@ -517,12 +520,16 @@ static int aspeed_get_fan_tach_ch_rpm(struct aspeed_pwm_tacho_data *priv,
fan_tach_ch_source = priv->fan_tach_ch_source[fan_tach_ch];
type = priv->pwm_port_type[fan_tach_ch_source];
- sec = (1000 / aspeed_get_fan_tach_ch_measure_period(priv, type));
- msleep(sec);
+ msec = (1000 / aspeed_get_fan_tach_ch_measure_period(priv, type));
+ usec = msec * 1000;
- regmap_read(priv->regmap, ASPEED_PTCR_RESULT, &val);
- if (!(val & RESULT_STATUS_MASK))
- return -ETIMEDOUT;
+ regmap_read_poll_timeout(
+ priv->regmap,
+ ASPEED_PTCR_RESULT,
+ val,
+ (val & RESULT_STATUS_MASK),
+ ASPEED_RPM_STATUS_SLEEP,
+ usec);
Are you sure you want to ignore the return value ? No more timeout ? Why ?
raw_data = val & RESULT_VALUE_MASK;
tach_div = priv->type_fan_tach_clock_division[type];
--
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